Atlas of Interventional Pain Management [4 ed.] 0323244289, 9780323244282

Table of contents :
Atlas of Interventional Pain Management
Copyright page
Dedication
Preface
Milepost 25
Video Contents
1 Atlanto-occipital Block Technique
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
2 Atlantoaxial Block Technique
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
3 Sphenopalatine Ganglion Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
4 Sphenopalatine Ganglion Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
5 Sphenopalatine Ganglion Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
6 Sphenopalatine Ganglion Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
7 Greater and Lesser Occipital Nerve Block
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
8 Greater and Lesser Occipital Nerve Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
9 Gasserian Ganglion Block
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Side Effects and Complications
10 Gasserian Ganglion Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
11 Gasserian Ganglion Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
12 Trigeminal Nerve Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
13 Selective Maxillary Nerve Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
14 Selective Mandibular Nerve Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
15 Supraorbital Nerve Block
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
16 Supratrochlear Nerve Block
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Side Effects and Complications
17 Infraorbital Nerve Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
18 Infraorbital Nerve Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
19 Mental Nerve Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
20 Mental Nerve Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
21 Inferior Alveolar Nerve Block
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
22 Auriculotemporal Nerve Block
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
23 Greater Auricular Nerve Block
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
24 Glossopharyngeal Nerve Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
25 Glossopharyngeal Nerve Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Side Effects and Complications
26 Glossopharyngeal Nerve Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
27 Vagus Nerve Block
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
28 Spinal Accessory Nerve Block
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
29 Phrenic Nerve Block
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
30 Facial Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
31 Superficial Cervical Plexus Block
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
32 Deep Cervical Plexus Block
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
33 Superior Laryngeal Nerve Block
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
34 Recurrent Laryngeal Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
35 Stellate Ganglion Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
36 Stellate Ganglion Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Side Effects and Complications
37 Stellate Ganglion Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
38 Stellate Ganglion Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
39 Third Occipital Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
40 Third Occipital Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
41 Cervical Facet Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
42 Cervical Facet Neurolysis:
Indications
Clinically Relevant Anatomy
Technique
Posterior Approach
Foraminal Approach
Side Effects and Complications
43 Cervical Facet Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
44 Cervical Epidural Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
45 Cervical Epidural Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
46 Lysis of Cervical Epidural Adhesions:
Abstract
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
47 Cervical Selective Nerve Root Block
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
48 Brachial Plexus Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark and Computed Tomography–Guided Techniques
Landmark Technique
Computed Tomography–Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
49 Brachial Plexus Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
50 Brachial Plexus Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
51 Brachial Plexus Block:
Abstract
Key Words
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
52 Suprascapular Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
53 Radial Nerve Block at the Humerus
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
54 Medial Cutaneous and Intercostobrachial Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Medial Cutaneous Nerve Block
Intercostobrachial Cutaneous Nerve Block
Side Effects and Complications
55 Radial Nerve Block at the Elbow
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
56 Median Nerve Block at the Elbow
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
57 Ulnar Nerve Block at the Elbow
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
58 Radial Nerve Block at the Wrist
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
59 Median Nerve Block at the Wrist
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
60 Ulnar Nerve Block at the Wrist
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
61 Metacarpal and Digital Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Metacarpal Nerve Block
Digital Nerve Block
Ultrasound-Guided Technique
Side Effects and Complications
62 Intravenous Regional Anesthesia
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
63 Thoracic Epidural Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Step 1: Obtain a Paramedian Sagittal Transverse Process Image
Step 2: Obtain a Paramedian Sagittal Articular Process Image
Step 3: Obtain a Paramedian Sagittal Oblique Image
Side Effects and Complications
64 Thoracic Epidural Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Step 1: Obtain a Paramedian Sagittal Transverse Process Image
Step 2: Obtain a Paramedian Sagittal Articular Process Image
Step 3: Obtain a Paramedian Sagittal Oblique Image
Side Effects and Complications
65 Thoracic Epidural Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Side Effects and Complications
66 Thoracic Paravertebral Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
67 Thoracic Facet Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Step 1: Obtain a Paramedian Sagittal Transverse Process Image
Step 2: Obtain a Paramedian Sagittal Articular Process Image
Side Effects and Complications
68 Thoracic Facet Block:
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Side Effects and Complications
69 Thoracic Facet Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Step 1: Obtain a Paramedian Sagittal Transverse Process Image
Step 2: Obtain a Paramedian Sagittal Articular Process Image
Side Effects and Complications
70 Thoracic Sympathetic Ganglion Block
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Side Effects and Complications
71 Intercostal Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Landmark Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
72 Intercostal Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
73 Interpleural Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
74 Interpleural Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
75 Splanchnic Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Side Effects and Complications
76 Splanchnic Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Side Effects and Complications
77 Celiac Plexus Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Side Effects and Complications
78 Celiac Plexus Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Side Effects and Complications
79 Celiac Plexus Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Side Effects and Complications
80 Celiac Plexus Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Side Effects and Complications
81 Celiac Plexus Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark, Fluoroscopically Guided, and Computed Tomography–Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Side Effects and Complications
82 Celiac Plexus Block:
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
83 Celiac Plexus Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark and Computed Tomography–Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
84 Transversus Abdominis Plane Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Two-Pop Technique
Ultrasound-Guided Technique
Side Effects and Complications
85 Anterior Cutaneous Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
86 Ilioinguinal Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
87 Iliohypogastric Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
88 Genitofemoral Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
89 Lumbar Sympathetic Ganglion Block
Indications
Clinically Relevant Anatomy
Technique
Landmark, Fluoroscopically Guided, and Computed Tomography–Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
90 Lumbar Sympathetic Ganglion Block:
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Side Effects and Complications
91 Lumbar Paravertebral Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
92 Lumbar Facet Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Step 1: Obtain a Paramedian Sagittal Transverse Process Image
Step 2: Obtain a Paramedian Sagittal Articular Process Image
Side Effects and Complications
93 Lumbar Facet Block:
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Side Effects and Complications
94 Lumbar Facet Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Ultrasound-Guided Technique
Step 1: Obtain a Paramedian Sagittal Transverse Process Image
Step 2: Obtain a Paramedian Sagittal Articular Process Image
Side Effects and Complications
95 Lumbar Gray Ramus Communicans Block
Indications
Clinically Relevant Anatomy
Technique
Landmark, Fluoroscopically Guided, and Computed Tomography–Guided Techniques
Landmark Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
96 Lumbar Gray Ramus Communicans Block:
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Side Effects and Complications
97 Lumbar Epidural Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Ultrasound-Guided Technique
Step 1: Obtain a Paramedian Sagittal Transverse Process Image
Step 2: Obtain a Paramedian Sagittal Articular Process Image
Step 3: Obtain a Paramedian Sagittal Oblique Image
Side Effects and Complications
98 Lumbar Epidural Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
99 Lumbar Selective Spinal Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Side Effects and Complications
100 Lumbar Subarachnoid Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark and Fluoroscopically Guided Technique
Side Effects and Complications
101 Lumbar Subarachnoid Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Side Effects and Complications
102 Lumbar Subarachnoid Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Step 1: Obtain a Paramedian Sagittal Transverse Process Image
Step 2: Obtain a Paramedian Sagittal Articular Process Image
Step 3: Obtain a Paramedian Sagittal Oblique Image
Side Effects and Complications
103 Lumbar Myelography
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
104 Superior Cluneal Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Side Effects and Complications
105 Caudal Epidural Nerve Block:
Indications
Clinically Relevant Anatomy
Sacrum
Coccyx
Sacral Hiatus
Sacral Canal
Contents of the Sacral Canal
Technique
Landmark Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
chapter.106 Caudal Epidural Nerve Block:
Indications
Clinically Relevant Anatomy
Sacrum
Coccyx
Sacral Hiatus
Sacral Canal
Contents of the Sacral Canal
Technique
Side Effects and Complications
107 Lysis of Epidural Adhesions:
Indications
Clinically Relevant Anatomy
Sacrum
Coccyx
Sacral Hiatus
Sacral Canal
Contents of the Sacral Canal
Technique
Fluoroscopically Guided Technique
Side Effects and Complications
108 Sacral Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
109 Sacroiliac Lateral Branch Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
110 Sacroiliac Lateral Branch Radiofrequency Lesioning
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Side Effects and Complications
111 Hypogastric Plexus Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
112 Hypogastric Plexus Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
113 Hypogastric Plexus Block:
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Side Effects and Complications
114 Hypogastric Plexus Block:
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Side Effects and Complications
115 Ganglion of Walther (Impar) Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Inferior Approach
Lateral Approach
Ultrasound-Guided Technique
Side Effects and Complications
116 Ganglion of Walther (Impar) Block:
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Side Effects and Complications
117 Pudendal Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
118 Pudendal Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
119 Sacroiliac Joint Injection
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
120 Sacroiliac Joint:
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Side Effects and Complications
121 Lumbar Plexus Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Side Effects and Complications
122 Lumbar Plexus Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
123 Lumbar Plexus Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
124 Femoral Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
125 Lateral Femoral Cutaneous Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
126 Obturator Nerve Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
127 Sciatic Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
128 Sciatic Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
129 Sciatic Nerve Block:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Side Effects and Complications
130 Piriformis Block
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Magnetic Resonance Imaging–Guided Technique
Ultrasound-Guided Technique
Side Effects and Complications
131 Sciatic Nerve Block at the Femur:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
132 Tibial Nerve Block at the Knee:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
133 Tibial Nerve Block at the Knee:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
134 Tibial Nerve Block at the Ankle
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
135 Saphenous Nerve Block at the Knee
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
136 Saphenous Nerve Block at the Ankle
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
137 Common Peroneal Nerve Block at the Knee:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
138 Common Peroneal Nerve Block at the Knee:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
139 Deep Peroneal Nerve Block at the Ankle
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
140 Superficial Peroneal Nerve Block at the Ankle
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
141 Sural Nerve Block at the Ankle
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Ultrasound-Guided Technique
Side Effects and Complications
142 Metatarsal and Digital Nerve Block of the Foot
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Metatarsal Nerve Block
Digital Nerve Block
Ultrasound-Guided Technique
Side Effects and Complications
143 Cervical Subarachnoid Neurolytic Block
Indications
Clinically Relevant Anatomy
Technique
Hypobaric Neurolytic Solution Technique
Hyperbaric Neurolytic Solution Technique
Side Effects and Complications
144 Lumbar Subarachnoid Neurolytic Block
Indications
Clinically Relevant Anatomy
Technique
Hypobaric Neurolytic Solution Technique
Hyperbaric Neurolytic Solution Technique
Side Effects and Complications
145 Implantation of Subcutaneously Tunneled One-Piece Epidural Catheters
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Side Effects and Complications
146 Implantation of Subcutaneously Tunneled Two-Piece Epidural Catheters
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Side Effects and Complications
147 Neuradenolysis of the Pituitary:
Indications
Clinically Relevant Anatomy
Technique
Preoperative Preparations
Needle-Through-Needle Technique
Postoperative Care
Side Effects and Complications
148 Cervical Diskography
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Side Effects and Complications
149 Thoracic Diskography
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Side Effects and Complications
150 Lumbar Diskography
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Side Effects and Complications
151 Epiduroscopy
Indications
Clinically Relevant Anatomy
Sacrum
Coccyx
Sacral Hiatus
Sacral Canal
Contents of the Sacral Canal
Technique
Side Effects and Complications
152 Intradiskal Electrothermal Annuloplasty
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Preprocedure Considerations
Patient Preparation and Positioning
Introducer Needle Placement
Catheter Placement
Heating Sequence
Postprocedure Care
Side Effects and Complications
153 Percutaneous Intradiskal Nucleoplasty
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Side Effects and Complications
154 Biacuplasty
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Preprocedure Considerations
Patient Preparation and Positioning
Introducer Needle Placement
Heating Sequence
Postprocedure Care
Side Effects and Complications
155 Percutaneous Diskectomy:
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Side Effects and Complications
156 Percutaneous Diskectomy:
Indications
Clinically Relevant Anatomy
Technique
Computed Tomography–Guided Technique
Side Effects and Complications
157 Percutaneous Laser-Assisted Annuloplasty
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Preprocedure Considerations
Patient Preparation and Positioning
Introducer Needle Placement
Postprocedure Care
Side Effects and Complications
158 Percutaneous Vertebroplasty
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Side Effects and Complications
159 Percutaneous Balloon Kyphoplasty
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Side Effects and Complications
160 Percutaneous Sacroplasty
Indications
Clinically Relevant Anatomy
Technique
Fluoroscopically Guided Technique
Computed Tomography–Guided Technique
Side Effects and Complications
161 Cervical Spinal Cord Stimulation:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Side Effects and Complications
162 Lumbar Spinal Cord Stimulation:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Side Effects and Complications
163 Spinal Cord Stimulation:
Indications
Clinically Relevant Anatomy
Technique
Landmark Technique
Side Effects and Complications
164 Peripheral Nerve Stimulation—Occipital Nerves
Indications
Clinically Relevant Anatomy
Technique
Percutaneous Lead Placement for Trial Stimulation
Side Effects and Complications
165 Implantation of Totally Implantable Reservoirs and Injection Ports
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
166 Implantation of Totally Implantable Infusion Pumps
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications (Fig. 166-13)
167 Percutaneous Posterior Facet Joint Spinal Fusion
Indications
Clinically Relevant Anatomy
Technique
Side Effects and Complications
Index
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
R
S
T
U
V
W

Citation preview

FOURTH EDITION

Atlas of Interventional Pain Management Steven D. Waldman, MD, JD Clinical Professor of Anesthesiology Clinical Professor of Medical Humanities and Bioethics University of Missouri–Kansas City School of Medicine Kansas City, Missouri

1600 John F. Kennedy Blvd. Ste 1800 Philadelphia, PA 19103-2899

ATLAS OF INTERVENTIONAL PAIN MANAGEMENT, ISBN: 978-0-323-24428-2 FOURTH EDITION Copyright © 2015, 2009, 2004, 1998 by Saunders, an imprint of Elsevier Inc. All rights reserved. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangements with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/permissions. This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein).

Notices Knowledge and best practice in this field are constantly changing. As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary. Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein. In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility. With respect to any drug or pharmaceutical products identified, readers are advised to check the most current information provided (i) on procedures featured or (ii) by the manufacturer of each product to be administered, to verify the recommended dose or formula, the method and duration of administration, and contraindications. It is the responsibility of practitioners, relying on their own experience and knowledge of their patients, to make diagnoses, to determine dosages and the best treatment for each individual patient, and to take all appropriate safety precautions. To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors, assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions, or ideas contained in the material herein. International Standard Book Number: 978-0-323-24428-2

Content Strategist: Michael Houston Content Development Specialist: Laura Schmidt Publishing Services Manager: Catherine Jackson Design Direction: Ellen Zanolle

Printed in China Last digit is the print number:

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7

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This book is dedicated to Dr. Steven Barag………. dear friend, mentor, philosopher, clinician, teacher, comedian, and the only guy I know who can wear an ascot and actually pull it off! Steve#2 Fall 2014

PREFACE

Milepost 25 —Mission Drift…..Course Correction……AKA……. Girls You Gotta Know When It’s Time to Turn the Page—

1st Interventional Pain Management Meeting in Nice, France, 1992. Left to right, Steven D. Waldman, MD, Ronald Melzack, PhD, and Alon Winnie, MD.

Since it is often said that pain is as old as man, it would seem that the meeting of a couple of hundred physicians with an interest in using invasive techniques to treat pain is hardly worth mentioning. However, it was at this meeting in Nice, France, organized by Alon Winnie and me, that a new subspecialty of pain medicine was born: interventional pain management. This specialty devoted its efforts to the use of neural blockade, implantable technologies, and neurodestructive procedures to treat pain. This is not to say that before this meeting, physicians were not using invasive techniques to treat pain, but rather that this was the first time many of those physicians got together in an organized fashion and began to define the subspecialty that we now refer to as interventional pain management. As I noted in the Preface to the third edition of Atlas of Interventional Pain Management, I came up with the term interventional pain management as a way to signal to potential attendees that this meeting would be about invasive procedures rather than about pills, hypnosis, biofeedback, and behavioral modalities, all of which were de rigueur at the time. Truth be told, at the meeting some suggested that “invasive pain management” would be a better name for our new subspecialty. Fortunately or not, depending on how you look at it, that name did not stick, so here were are today. To put this ancient history in the proper context, it is useful to look at where the specialty of pain management was back in those dark ages—before the advent of cell phones, personal computers, and Viagra—a time when most of the discussion surrounding pain treatment centered on tricyclic antidepressants, major tranquilizers, anticonvulsants, biofeedback, and behavior modification. Wait, you say! There was no specialty of pain management at that time, at least insofar as organized mainstream medicine was concerned! Twenty-five years ago there iv

were no organized training programs for pain management (with the exception of a few unofficial and uncertified training programs that were run by a rather eccentric group of anesthesiologists including Raj, Racz, Winnie, and myself), let alone any real fellowships. At that time, a very few of us devoted our practices solely to pain management. For most, pain management was a sideline, and for others it was an unwelcome interruption to their day; practitioners would grudgingly do a nerve block or two in the recovery room after spending a day giving anesthesia in the operating room. You might ask, what about the physical medicine and rehabilitation (PM & R) doctors and neurologists? They did not arrive on the pain management scene until much later. The first “official” examinations in pain management were not held until 1993. I remember flying to Chicago along with about 250 other “grandfathered” anesthesiologists to sit for a 3-hour written examination that was made up primarily of questions written by those of us who were taking the examination. It is hard to believe that although we wrote most of our own questions, the pass rate for this examination was only about 80%! Those of us who passed were awarded the dubious distinction of having qualified for a Certificate of Added Qualification in Pain Management by the American Board of Anesthesiology. To be honest, no one was clear on what that really meant or whether it was even worth listing on one’s curriculum vitae. Fast forward to 2015 and you will find that our specialty has come up in the world. Pain Medicine (its name had been changed from Pain Management in 2002) is now recognized by the American Board of Medical Specialties as a specialty worthy of its own full subspecialty board certification, a board certification that can be reached only after completing a 4-year residency in anesthesiology, physical medicine and rehabilitation, neurology, and so forth; completing a 1- to 2-year fellowship in pain medicine; and then passing a rigorous written examination. We have traveled quite a distance in 25 years, but these years have not been without growing pains, some good and some not so good. As the body of knowledge of interventional pain management began to become codified by the publishing of the first books in our specialty, such as Raj’s Practical Management of Pain and my textbooks Interventional Pain Management and the Atlas of Interventional Pain Management Techniques, organized fellowships in pain management began appearing. These training programs grew in both scope and stature; as a result, a critical mass of qualified interventional pain management specialists became available to care for the patient in pain. Interventional pain management procedures became the gold standard for pain treatment. As with most good things, some interventional pain management specialists, myself included, adopted the mantra that if a little was good,

PREFACE

more was better. To borrow a term from Alan Greenspan, there was a “frothy, irrational exuberance” insofar as interventional pain management procedures were concerned. Many interventional pain management specialists bragged that “there was no place in the body that they couldn’t put a needle!” Fortunately, as the specialty evolved, so did its practitioners, and with the help of new professional organizations such as the Society For Pain Practice Management, the American Society of Regional Anesthesia, and later the American Society of Interventional Pain Physicians under the tireless leadership of Lax Manchicanti, interventional pain specialists began to promulgate guidelines for best practices for our specialty and to the benefit of our patients. However, there was trouble in paradise. As the result of a paper based on only 38 patients published by Portenoy and Foley, many interventional pain management specialists (along with the rest of the medical community) were told that opioids—specifically Oxycontin and the like—were the panacea we were all looking for when treating the patient in pain. Interventional pain management specialists were admonished: “How dare you stick a needle in a patient suffering from back pain.” Portenoy and Foley concluded that “opioid maintenance therapy can be a safe, salutary and more humane alternative to the options of surgery or no treatment in those patients with intractable non-malignant pain and no history of drug abuse.” After all, we were told, pain was the fifth vital sign and the medical community was roundly chastised that it was being grossly undertreated. Many in our specialty drank the “opioid for non-malignant pain Kool Aid” and eschewed the time-proven beneficial procedures of interventional pain management, choosing instead to reach for the prescription pad. For a time, a feeling of guilt pervaded our specialty, especially whenever one of us picked up a needle or scalpel, and a Dark Ages of sort descended on interventional pain management. These guilt-ridden dark years dragged on as a relentless campaign gathered momentum, a campaign organized and funded by pharmaceutical companies to promote the use of opioids for chronic nonmalignant pain. Physicians were told that “opioids were a gift from nature,” and the few holdouts who refused to yield to this viewpoint were accused of suffering from opiophobia. Even the State Federation of Medical Boards and the Joint Commission yielded to this stealth program organized and financed by “big pharma” to sell opioids and jumped on the bandwagon. It seems that our specialty was at risk for obsolescence. It was indeed a dark time. To quote Thomas Paine, “A long habit of not thinking a thing wrong gives it a superficial appearance of being right.” Although many knew in their hearts that

v

the use of opioids as a first-line treatment for chronic nonmalignant pain was wrong, few spoke up. This silence on the part of organized medicine, and our specialty in particular, led to a public health disaster that could only be likened to the Black Plague of the Middle Ages, a pandemic that ultimately harmed millions of people! Fortunately, good triumphed over evil. As the deaths and ruined lives resulting from the inappropriate use of opioids mounted, a few voices within our specialty began to speak out against opioids, and once again interventional pain management specialists are putting away their prescription pads and turning to interventional procedures to treat their patients. Helping fuel this renewed enthusiasm for interventional pain management modalities has been the arrival of a totally unrelated development: the use of ultrasound guidance. Just as improvements in needle technology and implantable devices helped fuel the early growth of our specialty, huge improvements in ultrasound technology, both in terms of image resolution and ease of use, have made performing many interventional pain management procedures easier and safer for both the pain management specialist and the patient. Although time and experience will help define exactly where ultrasound fits within the practice of interventional pain management, I believe that most will agree that this imaging modality has been a great asset for our specialty. About this fourth edition of Atlas of Interventional Pain Management, a little information is in order. In its first three editions, the Atlas of Interventional Pain Management has enjoyed enormous success, becoming the largest selling pain management text currently in print. The various editions have been translated into more than 15 languages and have been a mainstay of education for a generation of interventional pain management physicians. My colleagues at Elsevier and I are very proud of these facts and have endeavored to make this fourth edition the best one yet. I have added 18 new chapters and more than 200 new full-color figures, and have greatly expanded information on the use of ultrasound guidance. The addition of over 100 how-to-do-it sections on ultrasound-guided interventional pain management techniques that are richly illustrated with full-color photographs showing transducer placement, patient positioning, and clearly marked ultrasound images should make this fourth edition of Atlas of Interventional Pain Management better than ever. As always, I hope you enjoy reading and using this text as much as I enjoyed writing it! Steven D. Waldman, MD, JD Fall 2014

VIDEO CONTENTS

x

1

Cervical Translaminar Epidural Block

6

Percutaneous Lumbar Diskectomy

2

Cervical Paravertebral Medial Branch Block

7

Radiofrequency Lesioning of the Lumbar Medial Branches

3

Percutaneous Facet Fusion

8

Spinal Cord Stimulation Trial

4

Lumbar Transforaminal Epidural Block

9

Cervical Lysis of Adhesions Racz Procedure

5

Caudal Epidural Block

10

Vertebroplasty

C H A P T E R

1

Atlanto-occipital Block Technique CPT-2015 Code First Joint Second Joint Third and Any Additional Joint Neurolytic First Level (Two Nerves)

64490 64491 64492 64633

Relative Value Units First Joint Second Joint Each Additional Joint Neurolytic First Level (Two Nerves)

12 12 12 30

INDICATIONS Atlanto-occipital block is useful in the diagnosis and treatment of painful conditions involving trauma or inflammation of the atlanto-occipital joint. These problems manifest clinically as neck pain, preauricular pain, and/or suboccipital headache pain and occasionally as suboccipital pain that radiates into the temporomandibular joint region. The patient may note an increase in pain when the joint is placed at extreme ranges of motion and may also experience associated nausea, difficulty concentrating, and sleep disturbance due to an inability to find a comfortable position when supine.

CLINICALLY RELEVANT ANATOMY The atlanto-occipital joint is dissimilar to the functional units of the lower cervical spine. The joint is not a true facet joint because it lacks posterior articulations characteristic of a true zygapophyseal joint. The atlanto-occipital joint allows the head to nod forward and backward with an isolated range of motion of about 35 degrees. This joint is located anterior to the posterolateral columns of the spinal cord. Neither the atlas nor the axis has an

intervertebral foramen to accommodate the first or second cervical nerves. These nerves are primarily sensory and, after leaving the spinal canal, travel through muscle and soft tissue laterally and then superiorly to contribute fibers to the greater and lesser occipital nerves. The atlanto-occipital joint is susceptible to arthritic changes and trauma secondary to acceleration-deceleration injuries. Such damage to the joint results in pain secondary to synovial joint inflammation and adhesions. The atlanto-occipital joint is different from the functional units of the lower cervical spine in that the joint is not a true facet joint because it lacks posterior articulations characteristic of a true zygapophyseal joint. The atlanto-occipital joint is susceptible to arthritic changes and trauma secondary to acceleration-deceleration injuries. Atlanto-occipital block is useful in the diagnosis and treatment of painful conditions involving trauma or inflammation of the atlanto-occipital joint. These problems manifest clinically as neck pain, preauricular pain, and/or suboccipital headache pain and occasionally as suboccipital pain that radiates into the temporomandibular joint region.

TECHNIQUE Fluoroscopically Guided Technique Atlanto-occipital block is usually done under fluoroscopic guidance because of the proximity of the joint to the spinal cord and vertebral artery, although some pain management specialists have gained sufficient familiarity with the procedure to perform it safely without fluoroscopy. The patient is placed in a prone position. Pillows are placed under the chest to allow moderate flexion of the cervical spine without discomfort to the patient. The forehead is allowed to rest on a folded blanket. If fluoroscopy is used, the beam is rotated in a sagittal plane from an anterior to a posterior position, which allows identification and visualization of the foramen 1

1

ATLANTO-OCCIPITAL BLOCK TECHNIQUE

ABSTRACT

KEY WORDS

The atlanto-occipital joint is different from the functional units of the lower cervical spine in that the joint is not a true facet joint because it lacks posterior articulations characteristic of a true zygapophyseal joint. The atlanto-occipital joint is susceptible to arthritic changes and trauma secondary to accelerationdeceleration injuries. Atlanto-occipital block is useful in the diagnosis and treatment of painful conditions involving trauma or inflammation of the atlanto-occipital joint. These problems manifest clinically as neck pain, preauricular pain, and/or suboccipital headache pain and occasionally as suboccipital pain that radiates into the temporomandibular joint region.

atlanto-occipital joint atlanto-occipital nerve block cervical spine headache neck pain

1.e1

osteoarthritis temporomandibular joint ultrasound-guided atlantooccipital nerve block zygapophyseal joint

2

SECTION I

HEAD

Occipital condyle

Foramen magnum

Needle in atlanto-occipital joint

Atlanto-occipital joint 1st cervical nerve

Atlas 2nd cervical nerve Vertebral artery

Axis

Figure 1-1

Spinal dura Anatomy of the atlanto-occipital joint.

magnum. Just lateral to the foramen magnum is the atlanto-occipital joint. A total of 5 mL of contrast medium suitable for intrathecal use is drawn up in a sterile 12-mL syringe. Then 3 mL of preservative-free local anesthetic is drawn up in a separate 5-mL sterile syringe. When the pain being treated is thought to be secondary to an inflammatory process, a total of 40 mg of depot-steroid is added to the local anesthetic with the first block, and 20 mg of depot-steroid is added with subsequent blocks. After preparation of the skin with antiseptic solution, a skin wheal of local anesthetic is raised at the site of needle insertion. An 18-gauge, 1-inch needle is inserted at the site to serve as an introducer. The fluoroscopy beam is aimed directly through the introducer needle, which appears as a small point on the fluoroscopy screen. The introducer needle is then repositioned under fluoroscopic guidance until this small point is visualized over the posterolateral aspect of the atlanto-occipital joint (Figs. 1-1 and 1-2). This lateral placement avoids trauma to the vertebral artery, which lies medial to the joint at this level. A 25-gauge, 31 2-inch styletted spinal needle is then inserted through the 18-gauge introducer. If bony contact is made, the spinal needle is withdrawn and the introducer needle is repositioned over the lateral aspect of the joint. The 25-gauge spinal needle is then readvanced until a pop is felt, indicating placement within the atlantooccipital joint. It is essential then to confirm that the needle is actually in the joint, which is anterior to the posterolateral aspect of the spinal cord (Fig. 1-3). This is accomplished by rotating the C-arm to the horizontal plane and confirming needle placement within the joint. If intra-articular placement cannot be confirmed, the needle should be withdrawn. After confirmation of needle placement within the atlanto-occipital joint, the stylet is removed from the

25-gauge spinal needle, and the hub is observed for blood or cerebrospinal fluid. If neither is present, gentle aspiration of the needle is carried out, and if no blood or cerebrospinal fluid is seen, 1 mL of contrast medium is slowly injected under fluoroscopy. An arthrogram of the normal atlanto-occipital joint reveals a bilateral concavity representing the intact joint capsule. However, if the joint has been traumatized, it is not unusual to see contrast medium flow freely from the torn joint capsule into the cervical epidural space. If the contrast medium is seen to

Figure 1-2

Fluoroscopic view of the needle over the posterolateral aspect of the atlanto-occipital joint.

1

ATLANTO-OCCIPITAL BLOCK TECHNIQUE

3

Mastoid process Foramen magnum Occipital condyle Atlanto-occipital joint Atlas Axis

Figure 1-3

Vertebral artery

Lateral view of the placement of the needle into the atlanto-occipital joint.

Spinal dura

rapidly enter the venous plexus rather than outline the joint, the needle is almost always not within the joint space. If this occurs, the needle should be repositioned into the joint before injection. If the contrast medium remains within the joint or if it outlines the joint and a small amount leaks into the epidural space, 1 to 1.5 mL of the local anesthetic and steroid is slowly injected through the spinal needle.

Ultrasound-Guided Technique The patient is placed in a prone position. Pillows are placed under the chest to allow moderate flexion of the cervical spine without discomfort to the patient. The forehead is allowed to rest on a folded blanket. After preparation of the skin overlying the injection site with antiseptic solution, a high-frequency linear ultrasound transducer is placed slightly off the midline in a transverse position (Fig. 1-4). The vertebral artery is then identified as it passes through the transverse vertebral foramen. Color Doppler imaging may assist in identification (Fig. 1-5). After the artery is identified, it is traced cranially under real-time ultrasound imaging until the artery is seen to turn medially in front of the atlanto-occipital joint (Fig. 1-6). The atlanto-occipital joint is identified, and at a point just lateral to the angle of the turn of the vertebral artery, a 22-gauge, 31 2-inch spinal needle is carefully advanced under real-time ultrasound guidance into the atlanto-occipital joint (Fig. 1-7).

SIDE EFFECTS AND COMPLICATIONS The proximity to the brain stem and spinal cord makes it imperative that this procedure be carried out only by

Figure 1-4

The patient is placed in a prone position with the cervical spine slightly flexed and the forehead placed on a folded towel. A highfrequency linear ultrasound transducer is placed slightly off the midline in a transverse position.

4

SECTION I

HEAD

VERTEBRAL ARTERY

C1 OCCIPUT

C1/OCCIPUT JOINT

Figure 1-5 Color Doppler image of the vertebral artery demonstrating how it turns medially in front of the atlanto-occipital joint.

Atlantooccipital joint Lateral atlantoaxial joint C3 dorsal root ganglion Vertebral artery

Figure 1-6 The vertebral artery passes cranially through the transverse vertebral foramen. It turns medially toward the midline. The atlantooccipital joint lies just in front of the turning vertebral artery.

VA

LATERAL

AO JOINT MEDIAL

Figure 1-7

Ultrasound image demonstrating the relationship of the vertebral artery (VA) to the atlanto-occipital (AO) joint.

1

A

ATLANTO-OCCIPITAL BLOCK TECHNIQUE

5

B

Figure 1-8

A, Sagittal T1-weighted (T1W) magnetic resonance (MR) image of an adult patient with Arnold-Chiari type II deformity. The posterior fossa is small with a widened foramen magnum. There is inferior displacement of the cerebellum and medulla with elongation of the pons and fourth ventricle (black arrow). The brain stem is kinked as it passes over the back of the odontoid. There is an enlarged massa intermedia (solid white arrow) and beaking of the tectum (dashed white arrow). B, Axial T2W MR image showing the small posterior fossa with beaking of the tectum (dashed black arrow). (From Waldman SD, Campbell RSD: Arnold-Chiari malformation type II. In Imaging of Pain. Philadelphia, Saunders, 2011, pp 29-30, Fig 9.1, A and B.)

those well versed in the regional anatomy and experienced in performing interventional pain management techniques. Fluoroscopic guidance is recommended for most practitioners because neural trauma is a possibility even in the most experienced hands. The proximity to the vertebral artery, combined with the vascular nature of

this anatomic region, makes the potential for intravascular injection high. Even small amounts of local anesthetic injected into the vertebral arteries will result in seizures. Given the proximity of the brain and brain stem, ataxia after atlanto-occipital block due to vascular uptake of local anesthetic is not an uncommon occurrence.

Clinical Pearls Atlanto-occipital block is often combined with atlantoaxial block when treating pain in the previously mentioned areas. Although neither joint is a true facet joint in the anatomic sense of the word, the block is analogous to the facet joint block technique used commonly by pain practitioners and may be viewed as such. Many pain management specialists believe that these techniques are currently underused in the treatment of so-called postwhiplash cervicalgia and cervicogenic headaches. These specialists believe that both techniques should be considered when cervical epidural nerve blocks and occipital nerve blocks fail to provide palliation of these headache and neck pain syndromes.

Any patient being considered for atlanto-occipital nerve block should undergo magnetic resonance imaging (MRI) of the head to rule out unsuspected intracranial and brain stem disease (Fig. 1-8). Furthermore, MRI of the cervical spine should be considered to rule out congenital abnormalities such as Arnold-Chiari malformations or posterior fossa tumors that may be the hidden cause of the patient’s headache symptoms. It should be noted that in some patients, the course of the vertebral artery covers the entire atlanto-occipital joint, which makes needle placement impossible. In such patients, a trial of occipital nerve stimulation may be a reasonable consideration.

C H A P T E R

2

Atlantoaxial Block Technique increase in pain when the joint is placed at extreme ranges of motion and may also experience associated nausea, difficulty concentrating, and sleep disturbance due to an inability to find a comfortable position when supine.

CPT-2015 Code First Joint Second Joint Third and Additional Joints Neurolytic First Level (Two Nerves)

64490 64491 64492 64633

CLINICALLY RELEVANT ANATOMY

Relative Value Units First Joint Second Joint Each Additional Joint Neurolytic First Level (Two Nerves)

12 12 12 30

INDICATIONS Atlantoaxial block is useful in the diagnosis and treatment of painful conditions involving trauma or inflammation of the atlantoaxial joint. These problems may manifest clinically as neck pain or suboccipital headache pain and occasionally as suboccipital pain that radiates into the temporomandibular joint region and is worsened with rotation of the joint. The patient may note an

The atlantoaxial joint is dissimilar to the functional units of the lower cervical spine. The joint is not a true facet joint because it lacks posterior articulations characteristic of a true zygapophyseal joint. Furthermore, there is no true disk or intervertebral foramen between atlas and axis. The atlantoaxial joint allows the greatest degree of motion of all the joints of the neck: it not only allows the head to flex and extend about 10 degrees but also allows more than 60 degrees of rotation in the horizontal plane. The integrity and stability of the atlantoaxial joint are almost entirely ligamentous in nature. Even minor injury of the ligaments due to trauma can result in joint dysfunction and pain. Severe disruption of the ligaments has the same effect as a fracture of the odontoid process and can result in paralysis and death. This joint is located lateral to the posterolateral columns of the spinal cord (Fig. 2-1). Neither the atlas nor the axis

Occipital condyle

Foramen magnum

Atlas 1st cervical nerve

Vertebral artery

2nd cervical nerve

Atlantoaxial joint

Axis

Figure 2-1 6

Spinal dura

Anatomy of the atlantoaxial joint.

2

ATLANTOAXIAL BLOCK TECHNIQUE

ABSTRACT

KEY WORDS

The atlantoaxial joint is different from the functional units of the lower cervical spine in that the joint is not a true facet joint because it lacks posterior articulations characteristic of a true zygapophyseal joint. The atlantoaxial joint is susceptible to arthritic changes and trauma secondary to accelerationdeceleration injuries. Atlantoaxial block is useful in the diagnosis and treatment of painful conditions involving trauma or inflammation of the atlantoaxial joint. Furthermore, there is no true disk or intervertebral foramen between atlas and axis. The atlantoaxial joint allows the greatest degree of motion of all the joints of the neck: it not only allows the head to flex and extend about 10 degrees but also allows more than 60 degrees of rotation in the horizontal plane. The integrity and stability of the atlantoaxial joint are almost entirely ligamentous in nature.

atlantoaxial joint atlantoaxial nerve block cervical spine headache neck pain osteoarthritis

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rheumatoid arthritis temporomandibular joint ultrasound-guided atlantoaxial nerve block zygapophyseal joint

2

has an intervertebral foramen to accommodate the first or second cervical nerves. These nerves are primarily sensory, and after leaving the spinal canal, they travel through muscle and soft tissue laterally and then superiorly to contribute fibers to the greater and lesser occipital nerves. The vertebral artery is lateral to the joint compared with the medial position of the artery relative to the atlanto-occipital joint. The atlantoaxial joint is susceptible to arthritic changes and trauma secondary to acceleration-deceleration injuries. Such damage to the joint results in pain secondary to synovial joint inflammation and adhesions. Rheumatoid arthritis may result in gradual erosion of the odontoid process that may present initially as occipital headaches. This erosion leads to instability of the atlantoaxial joint and ultimately may result in increased susceptibility to dislocation, paralysis, and death following seemingly minor trauma. In addition to rheumatoid arthritis, there are a number of other diseases associated with instability of the atlantoaxial joint, including Down’s syndrome, osteogenesis imperfecta, von Recklinghausen’s disease, congenital scoliosis, Larsen’s syndrome, Morquio’s syndrome, Kniest’s dysplasia, congenital spondyloepiphyseal dysplasia, and metatropic dysplasia.

TECHNIQUE Fluoroscopically Guided Technique Atlantoaxial block is usually done under fluoroscopic guidance because of the proximity to the spinal cord and vertebral artery, although some pain management specialists have gained sufficient familiarity with the procedure to perform it safely without fluoroscopy. The patient is placed in a prone position. Pillows are placed under the chest to allow the cervical spine to be moderately flexed without discomfort to the patient. The forehead is allowed to rest on a folded blanket. If fluoroscopy is used, the beam is rotated in a sagittal plane from an anterior to a posterior position, which allows identification and visualization of the foramen magnum and atlas. Just lateral and inferior to the atlas and to the foramen magnum is the atlantoaxial joint (see Fig. 2-1). A total of 5 mL of contrast medium suitable for intrathecal use is drawn up in a sterile 12-mL syringe. Then 3 mL of preservative-free local anesthetic is drawn up in a separate 5-mL sterile syringe. When the pain being treated is thought to be secondary to an inflammatory process, a total of 40 mg of depot-steroid is added to the local anesthetic with the first block, and 20 mg of depotsteroid is added with subsequent blocks. After preparation of the skin with antiseptic solution, a skin wheal of local anesthetic is raised at the site of needle insertion. An 18-gauge, 1-inch needle is placed at the insertion site to serve as an introducer. The fluoroscopy beam is aimed directly through the introducer needle, which appears as a small point on the fluoroscopy screen. The introducer needle is then repositioned under fluoroscopic guidance until this small point is visualized over the posterolateral aspect of the atlantoaxial joint (see Fig. 2-1). This lateral placement avoids trauma to the spinal cord, which lies medial to the joint

ATLANTOAXIAL BLOCK TECHNIQUE

7

at this level. It should be remembered that the vertebral artery is lateral to the atlantoaxial joint, and care must be taken to avoid arterial trauma or inadvertent intraarterial injection. A 25-gauge, 31 2-inch styletted spinal needle is then inserted through the 18-gauge introducer. If bony contact is made, the spinal needle is withdrawn, and the introducer needle is repositioned over the lateral aspect of the joint. The 25-gauge spinal needle is then readvanced until a pop is felt, indicating placement within the atlantoaxial joint (Fig. 2-2). It is essential then to confirm that the needle is actually in the joint, which is anterior to the posterolateral aspect of the spinal cord. This is accomplished by rotating the C-arm to the horizontal plane and confirming needle placement within the joint (Figs. 2-3 and 2-4). If intra-articular placement cannot be confirmed, the needle should be withdrawn. After confirmation of needle placement within the atlantoaxial joint, the stylet is removed from the 25gauge spinal needle, and the hub is observed for blood or cerebrospinal fluid. If neither is present, gentle aspiration of the needle is carried out, and if no blood or cerebrospinal fluid is seen, 1 mL of contrast medium is slowly injected under fluoroscopy. An arthrogram of the normal atlantoaxial joint reveals a bilateral concavity representing the intact joint capsule (Figs. 2-5 and 2-6). However, if the joint has been traumatized, it is not unusual to see contrast medium flow freely from the torn joint capsule into the cervical epidural space. If the contrast medium is seen to rapidly enter the venous plexus rather than outline the joint, the needle is almost always not within

Figure 2-2

Anteroposterior fluoroscopic view of the right lateral atlantoaxial joint with the needle tip on bone at the initial target point for an intra-articular block. (From King W, Borowczyk JM: Zygapophysial joint pain: procedures for diagnosis and treatment. In Lennard TA, Walkowski SA, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011, p 378, Fig 36-35.)

8

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HEAD

Mastoid process Foramen magnum Occipital condyle Atlas Atlantoaxial joint Axis Vertebral artery Spinal dura

Figure 2-3 Lateral view of the clinically relevant anatomy and proper needle placement for atlantoaxial block.

the joint space. If this occurs, the needle should be repositioned into the joint before injection. If the contrast medium remains within the joint or if it outlines the joint and a small amount leaks into the epidural space, 1 to 1.5 mL of the local anesthetic and steroid is slowly injected through the spinal needle.

Ultrasound-Guided Technique

Figure 2-4 Lateral fluoroscopic view of the right lateral atlantoaxial joint with the needle tip on bone at the initial target point for an intra-articular block. (From King W, Borowczyk JM: Zygapophysial joint pain: procedures for diagnosis and treatment. In Lennard TA, Walkowski SA, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011, p 378, Fig 36-36.)

Figure 2-5 Anteroposterior fluoroscopic view of a right lateral atlantoaxial arthrogram recorded to confirm correct placement of the needle tip for an intra-articular block. (From King W, Borowczyk JM: Zygapophysial joint pain: procedures for diagnosis and treatment. In Lennard TA, Walkowski SA, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011, p 379, Fig 36-38.)

The patient is placed in a prone position. Pillows are placed under the chest to allow moderate flexion of the cervical spine without discomfort to the patient. The forehead is allowed to rest on a folded blanket. After preparation of the skin overlying the injection site with antiseptic

2

ATLANTOAXIAL BLOCK TECHNIQUE

9

Figure 2-6

Lateral fluoroscopic view of a right lateral atlantoaxial arthrogram recorded to confirm correct placement of the needle tip for an intra-articular block. (From King W, Borowczyk JM: Zygapophysial joint pain: procedures for diagnosis and treatment. In Lennard TA, Walkowski SA, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011, p 379, Fig 36-37.)

solution, a high-frequency linear ultrasound transducer is placed in the transverse orientation at the level of the occiput (Fig. 2-7). The ultrasound transducer is then slowly moved in a caudad direction to identify the C1 and C2 vertebral bodies. The C2 vertebral body has a clearly visible bifid spinous process, whereas the spinous process on the C1 vertebral body is poorly seen because it is a vestigial structure (Fig. 2-8). After the C2 vertebra has been properly identified, the ultrasound transducer is slowly moved laterally until the vertebral artery is seen. Color Doppler may aid in the identification of the vertebral artery (Fig. 2-9). Lying between the exiting C2 nerve root and the vertebral artery is the atlantoaxial joint (Fig. 2-10). After the relative positions of the vertebral artery laterally, the C2 nerve root medially, and the atlantoaxial joint are identified, a 22-gauge, 31 2-inch styletted spinal needle is then advanced into the atlantoaxial joint using an out-of-plane approach under real-time ultrasonography.

Figure 2-7 Proper transverse placement of the high-frequency linear ultrasound transducer at the level of the occiput.

*

*

SIDE EFFECTS AND COMPLICATIONS The proximity to the brain stem and spinal cord makes it imperative that this procedure be carried out only by those well versed in the regional anatomy and experienced in performing interventional pain management techniques. Fluoroscopic guidance is recommended for most practitioners because neural trauma is a possibility even in the most experienced hands. The proximity to the vertebral artery, combined with the vascular nature of this anatomic region, makes the potential for intravascular injection high. Even small amounts of local anesthetic

C2

Figure 2-8 Transverse ultrasound image demonstrating the bifid nature of the C2 spinous process.

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VA

C2

Figure 2-9

Color Doppler image of the vertebral artery (VA).

injected into the vertebral arteries will result in seizures. Given the proximity of the brain and brain stem, ataxia after atlantoaxial block due to vascular uptake of local anesthetic is not an uncommon occurrence. Many patients also complain of a transient increase in headache and cervicalgia after injection of the joint.

Figure 2-11 Abnormalities of the cervical spine: odontoid process erosions. Lateral conventional tomogram reveals severe destruction of the odontoid process (arrows), which has been reduced to an irregular, pointed protuberance. (From Resnick D, Kransdorf MJ: Bone and Joint Imaging, 3rd ed. Philadelphia, Saunders, 2004, p 244.)

Clinical Pearls

Atlantooccipital joint Lateral atlantoaxial joint C3 dorsal root ganglion Vertebral artery

Figure 2-10

Lying between the exiting C2 nerve root and the vertebral artery is the atlantoaxial joint.

Atlantoaxial block is often combined with atlanto-occipital block when treating pain in the previously mentioned areas. Although neither joint is a true facet joint in the anatomic sense of the word, the block is analogous to the facet joint block technique used commonly by pain practitioners and may be viewed as such. Many pain management specialists believe that these techniques are currently underused in the treatment of so-called postwhiplash cervicalgia and cervicogenic headaches. These specialists believe that both techniques should be considered when cervical epidural nerve blocks and occipital nerve blocks fail to provide palliation of these headache and neck pain syndromes. Any patient being considered for atlantoaxial nerve block should undergo magnetic resonance imaging (MRI) of the head to rule out unsuspected intracranial and brain stem disease (Fig. E2-1). Furthermore, cervical spine radiography and computerized tomography of the cervical spine should be considered to rule out congenital abnormalities such as Arnold-Chiari malformations that may be the hidden cause of the patient’s headache symptoms as well as to identify erosion of the odontoid process in patients with rheumatoid arthritis (see Figs. E2-1 and 2-11).

2

ATLANTOAXIAL BLOCK TECHNIQUE

10.e1

A

Chamberlain’s line

B

C

Figure E2-1 Position of the dens in a normal patient (A), in a rheumatoid patient (B), and in a nonrheumatoid patient with basilar invagination and platybasia (C). A, Postmyelography computed tomogram with sagittal reformation demonstrates normal relationship of the dens with respect to the foramen magnum, brain stem, and anterior arch of C1. A normal atlantoaxial distance (AADI) is seen (arrow). B, T1-weighted sagittal magnetic resonance (MR) study of the cervical spine in a rheumatoid patient reveals erosion and pannus formation at the atlantoaxial joint resulting in increased AADI (arrow), posterior subluxation of the dens, and brain stem compression. C, Sagittal MR study of the brain in a nonrheumatoid patient shows normal AADI, but basilar invagination and platybasia have resulted in vertical subluxation of the dens and brain stem compression. The line drawn from the hard palate to the posterior lip of the foramen magnum is Chamberlain’s line (dotted line); basilar invagination is defined as extension of the odontoid tip 5 mm or more above this line. Also notice the fusion of the C2 and C3 vertebrae. The small, linear, dark line at the mid-C2 level is the subdental synchondrosis (arrow). (From Chi TL, Mirsky DM, Bello JA, et al: Airway imaging: principles and practical guide. In Habberg C, editor: Benumof and Hagberg’s Airway Management, 3rd ed. Philadelphia, Saunders, 2013, p 32, Fig 2-12.)

C H A P T E R

3

Sphenopalatine Ganglion Block: Transnasal Approach TECHNIQUE

CPT-2015 Code Local Anesthetic Neurolytic

64999 64999

Relative Value Units Local Anesthetic Neurolytic

8 20

INDICATIONS Sphenopalatine ganglion block may be used in the treatment of acute migraine headache, acute cluster headache, and a variety of facial neuralgias including Sluder’s, Vail’s, and Gardner’s syndromes. This technique is also useful in the treatment of status migrainosus and chronic cluster headache. There is anecdotal evidence that sphenopalatine ganglion block may also be useful in the palliation of pain secondary to acute herpes zoster of the trigeminal nerve. Neurodestructive procedures of the sphenopalatine ganglion using neurolytic agents, radiofrequency lesioning, or freezing may be indicated for the palliation of cancer pain and rarely for headache and facial pain syndromes that fail to respond to conservative management. Recent experience with electrical stimulation of the sphenopalatine ganglion has shown promising early results.

CLINICALLY RELEVANT ANATOMY The sphenopalatine ganglion (pterygopalatine, nasal, or Meckel’s ganglion) is located in the pterygopalatine fossa, posterior to the middle nasal turbinate (Figs. 3-1, 3-2, and 3-3). It is covered by a 1- to 1.5-mm layer of connective tissue and mucous membrane. This 5-mm triangular structure sends major branches to the gasserian ganglion, trigeminal nerves, carotid plexus, facial nerve, and superior cervical ganglion (see Fig. 3-2, Fig. 3-4). The sphenopalatine ganglion can be blocked by topical application of local anesthetic or by injection.

Sphenopalatine ganglion block through the transnasal approach is accomplished by the application of suitable local anesthetic to the mucous membrane overlying the ganglion. The patient is placed in the supine position, and the anterior nares are inspected for polyps, tumors, and foreign bodies. Three milliliters of either 2% viscous lidocaine or 10% cocaine is drawn up in a 5-mL sterile syringe. The tip of the patient’s nose is then drawn upward as if to place a nasogastric tube, and 0.5 mL of local anesthetic is injected into each nostril. The patient is asked to sniff vigorously to draw the local anesthetic posteriorly, which serves the double function of lubricating the nasal mucosa and providing topical anesthesia. Two 31 2-inch cotton-tipped applicators are soaked in the local anesthetic chosen, and one applicator is advanced along the superior border of the middle turbinate of each nostril until the tip comes into contact with the mucosa overlying the sphenopalatine ganglion (Fig. 3-5). Then 1 mL of local anesthetic is instilled over each cottontipped applicator. The applicator acts as a tampon that allows the local anesthetic to remain in contact with the mucosa overlying the ganglion. The applicators are removed after 20 minutes. If anatomic considerations such as the presence of polyps preclude the use of cotton-tipped applicators, transnasal endoscopically guided insertion of a 22-gauge, 31 2-inch needle may be considered (Fig. 3-6). The patient’s blood pressure, pulse, and respirations are monitored for untoward side effects.

SIDE EFFECTS AND COMPLICATIONS Because of the highly vascular nature of the nasal mucosa, epistaxis is the major complication of this technique. This vascularity can lead to significant systemic absorption of local anesthetic with resultant local anesthetic toxicity, especially when cocaine is used. Patients occasionally may experience significant orthostatic hypotension after sphenopalatine ganglion block. This can be a problem because postblock monitoring may be lax due to the benign-appearing nature of the technique. For this reason, patients who undergo sphenopalatine ganglion block should be monitored closely for orthostatic hypotension and initially allowed to ambulate only with assistance.

11

3

SPHENOPALATINE GANGLION BLOCK: TRANSNASAL APPROACH

ABSTRACT

KEY WORDS

The sphenopalatine ganglion (pterygopalatine, nasal, or Meckel’s ganglion) is located in the pterygopalatine fossa, posterior to the middle nasal turbinate. Sphenopalatine ganglion block may be used in the treatment of acute migraine headache, acute cluster headache, and a variety of facial neuralgias including Sluder’s, Vail’s, and Gardner’s syndromes. This technique is also useful in the treatment of status migrainosus and chronic cluster headache. The sphenopalatine ganglion can be blocked by topical application of local anesthetic or by injection.

cluster headache Gardner’s syndrome Meckel’s ganglion migraine headache pterygopalatine ganglion

11.e1

sphenopalatine ganglion sphenopalatine ganglion nerve block Vail’s syndrome

Right orbit

Infraorbital “bouquet” Anterior dental nerve Middle dental nerve Lacrimal gland Temporozygomatic nerve

Vomer Nasopalatine nerve

Anastomosis with the lacrimal nerve External sphenopalatine nerve

Orbital floor Infraorbital nerve

Anterior palatine nerve

Orbital branch Maxillary sinus Posterior alveolar (dental) nerve

Middle palatine nerve Posterior palatine nerve

Internal maxillary artery Inferior nasal nerve Orbital branch

Right nasal fossa

Maxillary nerve

Sphenopalatine nerve

Pterygoid process

Sphenopalatine ganglion Vidian nerve

Figure 3-1

The sphenopalatine ganglion (pterygopalatine, nasal, or Meckel’s ganglion) is located in the pterygopalatine fossa, posterior to the middle nasal turbinate. (From Barral JP, Croibier A: Maxillary nerve. In Manual Therapy for the Cranial Nerves. Edinburgh, Churchill Livingstone, 2009, pp 129-138.) Maxillary nerve Posterior dental nerve Oculomotor nerve Carotid plexus

Anterior alveolar nerve

Facial nerve

Middle alveolar nerve

Glossopharyngeal nerve Alveolar plexus Deep petrosal nerve

Internal jugular vein Inferior ganglion (X)

Sphenopalatine ganglion

Figure 3-2

Anatomy of the sphenopalatine (pterygopalatine) ganglion. Note that the sphenopalatine structure sends major branches to the gasserian ganglion, trigeminal nerves, carotid plexus, facial nerve, and superior cervical ganglion. (From Barral JP, Croibier A: Maxillary nerve. In Manual Therapy for the Cranial Nerves. Edinburgh, Churchill Livingstone, 2009, pp 129-138.)

3

Right

SPHENOPALATINE GANGLION BLOCK: TRANSNASAL APPROACH

13

Left

Figure 3-3 Axial computed tomographic cuts through the region of the sphenopalatine ganglion. The right side of each image was not dissected. The left side of each image was dissected and a radiopaque marker placed in the pterygopalatine fossa to indicate the position of the sphenopalatine ganglion (arrows). (From De Salles AAF, Gorgulho A, Golish SR, et al: Technical and anatomical aspects of novalis stereotactic radiosurgery sphenopalatine ganglionectomy. Int J Radiat Oncol Biol Phys 66[4 suppl]:S53-S57, 2006.)

Figure 3-4

View of the pterygopalatine fossa through Meckel’s cave. Notice the upper retraction instrument lifting the second division of the trigeminal nerve to expose the sphenopalatine ganglion (tip of lower instrument). (From De Salles AAF, Gorgulho A, Golish SR, et al: Technical and anatomical aspects of novalis stereotactic radiosurgery sphenopalatine ganglionectomy. Int J Radiat Oncol Biol Phys 66[4 suppl]:S53-S57, 2006.)

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Cotton-tipped applicator

Middle nasal turbinate

Sphenopalatine ganglion

Figure 3-5

Two 3 1 2-inch cotton-tipped applicators are soaked in the local anesthetic chosen, and one applicator is advanced along the superior border of the middle turbinate of each nostril until the tip comes into contact with the mucosa overlying the sphenopalatine ganglion.

Clinical Pearls

MT

Septum

N.Ph

IT

Figure 3-6

Under control of an endoscope (4 mm, 0 degrees), a long 20-gauge needle is passed between the middle turbinate (MT) and inferior turbinate (IT) and inserted into the mucosa just behind and over the middle turbinate tail, seeking the sphenopalatine foramen. N.Ph, Nasopharynx. (From Ali AR, Sakr SA, Rahman ASMA: Bilateral sphenopalatine ganglion block as adjuvant to general anaesthesia during endoscopic trans-nasal resection of pituitary adenoma. Egypt J Anaesth 26[4]:273-280, 2010.)

Clinical experience has shown that sphenopalatine ganglion block with local anesthetic is useful in aborting the acute attack of migraine or cluster headache. The simplicity of the transnasal approach lends itself to use at the bedside, in the emergency room, or in the pain clinic. Although cocaine is probably a superior topical anesthetic for use with this technique, the various political issues surrounding the use of controlled substances make another local anesthetic such as viscous lidocaine a more logical choice. For the acute headache sufferer, this technique can be combined with the inhalation of 100% oxygen via mask through the mouth while the cotton-tipped applicators are in place. Experience has shown that this technique aborts about 80% of cluster headaches. Sphenopalatine ganglion block should be carried out on a daily basis with the endpoint of complete pain relief. This usually occurs within five block procedures.

4

C H A P T E R

Sphenopalatine Ganglion Block: Greater Palatine Foramen Approach IF

CPT-2015 Code Local Anesthetic Neurolytic

64999 64999

MSS

Relative Value Units Local Anesthetic Neurolytic

M1 8 20

INDICATIONS Sphenopalatine ganglion block may be used in the treatment of acute migraine headache, acute cluster headache, and a variety of facial neuralgias including Sluder’s, Vail’s, and Gardner’s syndromes. This technique is also useful in the treatment of status migrainosus and chronic cluster headache. There is anecdotal evidence that sphenopalatine ganglion block may also be useful in the palliation of pain secondary to acute herpes zoster of the trigeminal nerve. The greater palatine foramen approach to sphenopalatine ganglion block is useful in patients who have an alteration of the nasal anatomy secondary to trauma or malignancy that would preclude use of the transnasal approach. Neurodestructive procedures of the sphenopalatine ganglion using neurolytic agents, radiofrequency lesioning, or freezing may be indicated for the palliation of cancer pain and rarely for headache and facial pain syndromes that fail to respond to conservative management. Recent experience with electrical stimulation of the sphenopalatine ganglion has shown promising early results.

M2 GPF

MSL

LPF

PNS

Figure 4-1 Ventral view of the hard palate. GPF, Greater palatine foramen; IF, incisive foramen; LPF, lesser palatine foramina; M1, M2, first and second molars; MSL, middle sagittal line; MSS, middle sagittal suture; PNS, posterior nasal spine. (From Piagkou M, Xanthos T, Anagnostopoulou S, et al: Anatomical variation and morphology in the position of the palatine foramina in adult human skulls from Greece. J Craniomaxillofac Surg 40[7]:e206-e210, 2012.)

GPF

CLINICALLY RELEVANT ANATOMY The sphenopalatine ganglion (pterygopalatine, nasal, or Meckel’s ganglion) is located in the pterygopalatine fossa, posterior to the middle nasal turbinate. It is covered by a 1- to 1.5-mm layer of connective tissue and mucous membrane. This 5-mm triangular structure sends major branches to the gasserian ganglion, trigeminal nerves, carotid plexus, facial nerve, and superior cervical ganglion. The sphenopalatine ganglion can be blocked by topical application of local anesthetic via the transnasal approach or by injection via the lateral approach or injection through the greater palatine foramen. The greater palatine foramen is crescent shaped and allows for passage of the greater palatine nerve and the descending palatine vessels (Figs. 4-1 and 4-2).

M1

Greater palatine artery and nerve M2

M3

Figure 4-2 Greater palatine foramen (GPF) and its content (greater palatine artery, vein, and nerve). M1, M2, M3, first, second, and third molars. (From Piagkou M, Xanthos T, Anagnostopoulou S, et al: Anatomical variation and morphology in the position of the palatine foramina in adult human skulls from Greece. J Craniomaxillofac Surg 40[7]:e206-e210, 2012.) 15

4

SPHENOPALATINE GANGLION BLOCK: GREATER PALATINE FORAMEN APPROACH

ABSTRACT

KEY WORDS

The sphenopalatine ganglion (pterygopalatine, nasal, or Meckel’s ganglion) is located in the pterygopalatine fossa, posterior to the middle nasal turbinate. Sphenopalatine ganglion block may be used in the treatment of acute migraine headache, acute cluster headache, and a variety of facial neuralgias including Sluder’s, Vail’s, and Gardner’s syndromes. This technique is also useful in the treatment of status migrainosus and chronic cluster headache. The sphenopalatine ganglion can be blocked by topical application of local anesthetic or by injection. The greater palatine foramen approach to sphenopalatine ganglion block is useful in patients who have an alteration of the nasal anatomy secondary to trauma or malignancy that would preclude use of the transnasal approach.

cluster headache Gardner’s syndrome greater palatine foramen Meckel’s ganglion migraine headache neurolytic sphenopalatine ganglion block

15.e1

pterygopalatine ganglion sphenopalatine ganglion sphenopalatine ganglion nerve block Vail’s syndrome

16

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TECHNIQUE Sphenopalatine ganglion block via the greater palatine foramen approach is accomplished by the injection of local anesthetic onto the ganglion. The patient is placed in the supine position with the cervical spine extended over a foam wedge. The greater palatine foramen is identified just medial to the gum line of the third molar on the posterior portion of the hard palate. A 25-gauge, 2-inch needle is advanced about 2.5 cm through the foramen in a superior and slightly posterior trajectory (Fig. 4-3). Use of an angled dental needle may facilitate needle placement into the greater palatine foramen, especially in patients who are unable to fully open their mouths (Figs. 4-4 and 4-5). The maxillary nerve is just superior to the ganglion, and if the needle is advanced too deep, a paresthesia may be elicited. After careful, gentle aspiration, 2 mL of local anesthetic is slowly injected.

SIDE EFFECTS AND COMPLICATIONS Because of the highly vascular nature of this anatomic region, significant systemic absorption of local anesthetic with resultant local anesthetic toxicity is a distinct possibility. This approach to sphenopalatine ganglion block should be avoided in patients who have intraoral infections, including herpes zoster (Fig. 4-6). Patients occasionally may experience significant orthostatic hypotension after sphenopalatine ganglion block. Therefore, patients who undergo sphenopalatine ganglion block should be monitored closely for orthostatic hypotension and initially allowed to ambulate only with assistance.

Figure 4-3

Placement of a needle into the greater palatine foramen. (From McDonald RE, Avery DR, Dean JA, et al: Local anesthesia and pain control for the child and adolescent. In Dean JA, Avery DR, McDonald RE, editors: McDonald and Avery’s Dentistry for the Child and Adolescent, 9th ed. St Louis, Mosby, 2011, pp 241-252.)

3rd molar

Maxillary nerve

Greater palatine foramen Sphenopalatine ganglion Needle 3rd molar Greater palatine foramen Palatine nerves Sphenopalatine ganglion

Figure 4-4 Proper needle placement for sphenopalatine ganglion block using the greater palatine foramen approach.

4

SPHENOPALATINE GANGLION BLOCK: GREATER PALATINE FORAMEN APPROACH

17

Figure 4-6

Recurrent intraoral herpes lesions are a contraindication to sphenopalatine ganglion block via the greater palatine foramen. (From Scully C: Herpesvirus infections. In Oral and Maxillofacial Medicine, 3rd ed. New York, Churchill Livingstone, 2013, pp 277-285.)

Figure 4-5 Lateral fluoroscopic view of the tip of an angled dental needle placed through the greater palatine foramen. Clinical Pearls Clinical experience has shown that sphenopalatine ganglion block with local anesthetic is useful in aborting the acute attack of migraine or cluster headache. The simplicity of the transnasal approach lends itself to use at the bedside, in the emergency room, or in the pain clinic. Although cocaine is probably a superior topical anesthetic for use with this technique, the various political issues surrounding the use of controlled substances make another local anesthetic such as viscous lidocaine a more logical choice. If previous trauma or tumor precludes the use of the transnasal approach to sphenopalatine ganglion block, injection via the greater palatine foramen represents a good alternative. Because of the proximity of the sphenopalatine ganglion to the maxillary nerve, care must be taken to avoid inadvertent

neurolysis of the maxillary nerve when performing neurodestructive procedures on the sphenopalatine ganglion. Because the sphenopalatine ganglion can be localized more accurately by stimulation, radiofrequency lesioning via the lateral approach probably represents the safest option if destruction of the sphenopalatine ganglion is desired. For the acute headache sufferer, this technique can be combined with the inhalation of 100% oxygen via mask after the injection of local anesthetic. Experience has shown that this technique aborts about 80% of cluster headaches. Sphenopalatine ganglion block should be carried out on a daily basis with the endpoint of complete pain relief. This usually occurs within five block procedures.

18

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HEAD

C H A P T E R

5

Sphenopalatine Ganglion Block: Lateral Approach TECHNIQUE

CPT-2015 Code Local Anesthetic Neurolytic

64999 64999

Relative Value Units Local Anesthetic Neurolytic

8 20

INDICATIONS Sphenopalatine ganglion block may be used in the treatment of acute migraine headache, acute cluster headache, and a variety of facial neuralgias including Sluder’s, Vail’s, and Gardner’s syndromes. The technique is also useful in the treatment of status migrainosus and chronic cluster headache. There is anecdotal evidence that sphenopalatine ganglion block may also be useful in the palliation of pain secondary to acute herpes zoster of the trigeminal nerve. The lateral approach to sphenopalatine ganglion block is useful in patients who have an alteration of the nasal anatomy secondary to trauma or malignancy that would preclude use of the transnasal approach. It is also the preferred route for neurodestructive procedures of the sphenopalatine ganglion. Neurodestruction of the sphenopalatine ganglion may be performed with neurolytic agents, radiofrequency lesioning, or freezing and is indicated for the palliation of cancer pain and rarely for headache and facial pain syndromes that fail to respond to conservative management. Recent experience with electrical stimulation of the sphenopalatine ganglion has shown promising early results.

CLINICALLY RELEVANT ANATOMY The sphenopalatine ganglion (pterygopalatine, nasal, or Meckel’s ganglion) is located in the pterygopalatine fossa, posterior to the middle nasal turbinate. It is covered by a 1- to 1.5-mm layer of connective tissue and mucous membrane. This 5-mm triangular structure sends major branches to the gasserian ganglion, trigeminal nerves, carotid plexus, facial nerve, and superior cervical ganglion (Fig. 5-1). The sphenopalatine ganglion can be blocked by topical application of local anesthetic via the transnasal approach, by injection via the pterygopalatine fossa or through the greater palatine foramen, or by lateral placement of a needle via the coronoid notch. 18

Landmark and Fluoroscopically Guided Technique Sphenopalatine ganglion block via the lateral approach is accomplished by the injection of local anesthetic onto the ganglion via a needle placed through the coronoid notch. The patient is placed in the supine position with the cervical spine in the neutral position. The coronoid notch is identified by asking the patient to open and close the mouth several times and palpating the area just anterior and slightly inferior to the acoustic auditory meatus (Fig. 5-2). After the notch is identified, the patient is asked to hold the mouth open in the neutral position. A total of 2 mL of local anesthetic is drawn up in a 3-mL sterile syringe. Some pain management specialists empirically add a small amount of depot-steroid preparation to the local anesthetic. After the skin overlying the coronoid notch is prepared with antiseptic solution, a 22-gauge, 31 2-inch styletted needle is inserted just below the zygomatic arch directly in the middle of the coronoid notch. The needle is advanced about 1.5 to 2 inches in a plane perpendicular to the skull until the lateral pterygoid plate is encountered. At this point, the needle is withdrawn slightly and redirected slightly superior and anterior, with the goal of placing the needle just above the lower aspect of the lateral pterygoid plate so that it can enter the pterygopalatine fossa below the maxillary nerve and in close proximity to the sphenopalatine ganglion (Fig. 5-3). If this procedure is performed under fluoroscopy, the needle tip is visualized just under the lateral nasal mucosa, and its position can be confirmed by injecting 0.5 mL of contrast medium (Fig. 5-4). Additional confirmation of needle position can be obtained by needle stimulation at 50 Hz. If the needle is in the correct position, the patient experiences a buzzing sensation just behind the nose with no stimulation into the distribution of other areas innervated by the maxillary nerve. After correct needle placement is confirmed, careful aspiration is carried out, and 2 mL of solution is injected in incremental doses. During the injection procedure, the patient must be observed carefully for signs of local anesthetic toxicity. Because of the proximity of the maxillary nerve, the patient also may experience partial blockade of the maxillary nerve.

Ultrasound-Guided Technique The coronoid notch is identified as described in the previous section (see Fig. 5-2) and the skin overlying the notch is then prepared with antiseptic solution. A linear

5

SPHENOPALATINE GANGLION BLOCK: LATERAL APPROACH

ABSTRACT

KEY WORDS

The sphenopalatine ganglion (pterygopalatine, nasal, or Meckel’s ganglion) is located in the pterygopalatine fossa, posterior to the middle nasal turbinate. Sphenopalatine ganglion block may be used in the treatment of acute migraine headache, acute cluster headache, and a variety of facial neuralgias including Sluder’s, Vail’s, and Gardner’s syndromes. This technique is also useful in the treatment of status migrainosus and chronic cluster headache. The sphenopalatine ganglion can be blocked by topical application of local anesthetic or by injection. The greater palatine foramen approach to sphenopalatine ganglion block is useful in patients who have an alteration of the nasal anatomy secondary to trauma or malignancy that would preclude use of the transnasal approach.

cluster headache coronoid notch Gardner’s syndrome maxillary nerve Meckel’s ganglion migraine headache neurolytic sphenopalatine ganglion block

18.e1

pterygopalatine fossa pterygopalatine ganglion sphenopalatine ganglion sphenopalatine ganglion nerve block Vail’s syndrome

5

SPHENOPALATINE GANGLION BLOCK: LATERAL APPROACH

19

Maxillary nerve Posterior dental nerve Oculomotor nerve Carotid plexus

Anterior alveolar nerve

Facial nerve

Middle alveolar nerve

Glossopharyngeal nerve Alveolar plexus Deep petrosal nerve

Internal jugular vein Inferior ganglion (X)

Sphenopalatine ganglion

Figure 5-1

Anatomy of the sphenopalatine (pterygopalatine) ganglion. Note that the sphenopalatine (pterygopalatine) structure sends major branches to the gasserian ganglion, trigeminal nerves, carotid plexus, facial nerve, and superior cervical ganglion. (From Barral JP, Croibier A: Maxillary nerve. In Manual Therapy for the Cranial Nerves, Edinburgh, Churchill Livingstone, 2009, pp 129-138.)

transducer is then placed in the transverse plane directly over the mandibular notch. The masseter muscle is easily identified by following its origin on the zygomatic arch (Fig. 5-5). Just below and deep to the masseter muscle is the pterygopalatine fossa. The ultrasound transducer is moved slightly craniad and caudad until the maxillary nerve is clearly identified within the pterygopalatine fossa. After the maxillary nerve is identified, a 22-gauge, 10-cm straight styletted radiofrequency needle with a 2-mm active tip is inserted at a point just below the zygomatic arch in the middle of the coronoid notch using an out-of-plane approach. The needle is advanced under real-time ultrasound guidance until the tip rests just below the previously identified maxillary nerve. If a

paresthesia in the distribution of the maxillary nerve is elicited, the needle should be withdrawn and redirected in a slightly superior and anterior trajectory allowing the needle tip to pass just above the inferior aspect of the lateral pterygoid plate to permit entry into the pterygopalatine fossa just below the maxillary nerve and in proximity to the sphenopalatine ganglion (Fig. 5-6). When the operator is satisfied with the position of the needle tip, stimulation of the needle at 50 Hz should be carried out. If the patient experiences a stimulation pattern involving the gingiva, incisors, canine, and premolar teeth on the ipsilateral side, then the needle tip is too close to the maxillary nerve and must be repositioned caudally and medially. If the patient reports a buzzing sensation within his or her nose, without any stimulation of the ipsilateral gingiva and/or teeth, the needle tip is in satisfactory position and, after careful aspiration, the solution may be carefully injected.

SIDE EFFECTS AND COMPLICATIONS

Figure 5-2 The coronoid notch is identified by asking the patient to open and close the mouth several times and palpating the area just anterior and slightly inferior to the acoustic auditory meatus.

Because of the highly vascular nature of the pterygopalatine fossa, significant facial hematoma may occur after sphenopalatine ganglion block via the lateral approach. This vascularity means that the pain management specialist should use small, incremental doses of local anesthetic to avoid local anesthetic toxicity. Patients occasionally may experience significant orthostatic hypotension after sphenopalatine ganglion block. Therefore, patients who undergo sphenopalatine ganglion block should be monitored closely for orthostatic hypotension and initially allowed to ambulate only with assistance.

20

SECTION I

HEAD

Sphenopalatine fossa

V1

V2 V3 Lateral pterygoid plate

Sphenopalatine ganglion

Figure 5-3 Proper needle placement for sphenopalatine ganglion block using the lateral approach.

Coronoid notch

Figure 5-4

Anteroposterior fluoroscopic image showing the tip of the needle with spread of the contrast agent along the lateral wall of the nasal cavity in proximity to the sphenopalatine ganglion. (From Narouze S: Complications of head and neck procedures. Tech Reg Anesth Pain Manag 11[3]:171-177, 2007.)

Figure 5-5

Proper transducer position for sphenopalatine ganglion block via the lateral pterygoid approach.

Clinical Pearls

Zygomatic arch

MASSETER

Temporalis

Maxillary N

Anterior

Figure 5-6

Sphenopalatine ganglion

Transverse ultrasound image of the sphenopalatine ganglion. N, Nerve.

Clinical experience has shown that sphenopalatine ganglion block with local anesthetic is useful in aborting the acute attack of migraine or cluster headache. The simplicity of the transnasal approach lends itself to use at the bedside, in the emergency room, or in the pain clinic. Although cocaine is probably a superior topical anesthetic for use with this technique, the various political issues surrounding the use of controlled substances make another local anesthetic such as viscous lidocaine a more logical choice. If previous trauma or tumor precludes the use of the transnasal approach to sphenopalatine ganglion block, injection of local anesthetic via the greater palatine foramen or the lateral approach represents a good alternative. Because of the proximity of the sphenopalatine ganglion to the maxillary nerve, care must be taken to avoid inadvertent neurolysis of the maxillary nerve when performing neurodestructive procedures on the sphenopalatine ganglion. Because of the ability to more accurately localize the sphenopalatine ganglion by stimulation, radiofrequency lesioning via the lateral approach represents probably the safest option if destruction of the sphenopalatine ganglion is desired. For the acute headache sufferer, this technique can be combined with the inhalation of 100% oxygen via mask after the injection of local anesthetic. Experience has shown that this technique aborts about 80% of cluster headaches. Sphenopalatine ganglion block should be carried out on a daily basis with the endpoint of complete pain relief. This usually occurs within five to eight block procedures.

6

SPHENOPALATINE GANGLION BLOCK: RADIOFREQUENCY LESIONING

C H A P T E R

21

6

Sphenopalatine Ganglion Block: Radiofrequency Lesioning CPT-2015 Code Neurolytic

64640

Relative Value Unit Neurolytic

20

INDICATIONS Radiofrequency lesioning of the sphenopalatine ganglion block may be used in the treatment of chronic cluster headache, cancer pain, and a variety of facial neuralgias

including Sluder’s, Vail’s, and Gardner’s syndromes that have failed to respond to more conservative treatments. The lateral approach to sphenopalatine ganglion block is used to place the radiofrequency needle, although the transnasal and greater palatine foramen approach can be used in patients who have an alteration of the nasal anatomy secondary to trauma or malignancy that would preclude use of the lateral approach. Neurodestructive procedures of the sphenopalatine ganglion using the lateral approach may be performed with neurolytic agents, freezing, or radiofrequency lesioning. Radiofrequency lesioning has the added advantage of allowing the use of a stimulating needle, which facilitates correct needle placement.

6

SPHENOPALATINE GANGLION BLOCK: RADIOFREQUENCY LESIONING

ABSTRACT

KEY WORDS

The sphenopalatine ganglion (pterygopalatine, nasal, or Meckel’s ganglion) is located in the pterygopalatine fossa, posterior to the middle nasal turbinate. Sphenopalatine ganglion block may be used in the treatment of acute migraine headache, acute cluster headache, and a variety of facial neuralgias including Sluder’s, Vail’s, and Gardner’s syndromes. This technique is also useful in the treatment of status migrainosus and chronic cluster headache. The sphenopalatine ganglion can be blocked by topical application of local anesthetic or by injection. The greater palatine foramen approach to sphenopalatine ganglion block is useful in patients who have an alteration of the nasal anatomy secondary to trauma or malignancy that would preclude use of the transnasal approach.

cluster headache coronoid notch Gardner’s syndrome maxillary nerve Meckel’s ganglion migraine headache neurolytic sphenopalatine ganglion block

21.e1

pterygopalatine fossa pterygopalatine ganglion radiofrequency destruction of the sphenopalatine ganglion sphenopalatine ganglion sphenopalatine ganglion nerve block Vail’s syndrome

22

SECTION I

HEAD

Olfactory nerve

Maxillary nerve (V2)

Vidian nerve in pterygoid canal Internal carotid artery and carotid plexus

External nasal nerve (V1) Internal lateral branch, anterior ethmoidal nerve Posterior nasal branches

Spenopalatine ganglion Nasopalatine nerve

Posterior palatine nerve

Anterior palatine nerve

Middle palatine nerve

Figure 6-1

Anatomy of the sphenopalatine ganglion within the pterygopalatine fossa. (From Narouze S: Complications of head and neck procedures. Tech Reg Anesth Pain Manag 11[3]:171-177, 2007.)

CLINICALLY RELEVANT ANATOMY The sphenopalatine ganglion (pterygopalatine, nasal, or Meckel’s ganglion) is located in the pterygopalatine fossa, posterior to the middle nasal turbinate (Fig. 6-1). It is covered by a 1- to 1.5-mm layer of connective tissue and mucous membrane. This 5-mm triangular structure sends major branches to the gasserian ganglion, trigeminal nerves, carotid plexus, facial nerve, and superior cervical ganglion. The sphenopalatine ganglion can be blocked by topical application of local anesthetic via the transnasal approach, by injection via the pterygopalatine fossa or through the greater palatine foramen, or by lateral placement of a needle via the coronoid notch.

Cotton-tipped applicator

TECHNIQUE Radiofrequency lesioning of the sphenopalatine ganglion block is accomplished by placing a radiofrequency needle in proximity to the sphenopalatine ganglion using the lateral approach via an introducer needle. The patient is placed in the supine position with the cervical spine in the neutral position. A 31 2-inch cotton-tipped applicator is soaked in contrast medium and placed between the middle and inferior turbinates to serve as a radiopaque marker (Figs. 6-2 and 6-3). A total of 2 mL of local anesthetic is drawn up in a 3-mL sterile syringe. After the skin lateral to the angle of the

Figure 6-2

Anteroposterior fluoroscopic image demonstrating the placement of a 3 1 2-inch cotton-tipped applicator that has been soaked in contrast medium and placed between the middle and inferior turbinates to serve as a radiopaque marker.

6

SPHENOPALATINE GANGLION BLOCK: RADIOFREQUENCY LESIONING

23

Pterygopalatine fossa Posterior clinoid Cotton-tipped applicator

Figure 6-3 Lateral fluoroscopic image demonstrating the placement of a 3 1 2-inch cotton-tipped applicator that has been soaked in contrast medium and placed between the middle and inferior turbinates to serve as a radiopaque marker.

Figure 6-4

Lateral fluoroscopic image demonstrating placement of the stimulating needle in the pterygopalatine fossa in proximity to the sphenopalatine ganglion.

SIDE EFFECTS AND COMPLICATIONS

mouth is prepared with antiseptic solution, a 22-gauge, 10-cm insulated blunt curved needle with a 5- to 10-mm active tip is inserted through an introducer needle placed through the previously anesthetized area. The needle is advanced toward the tip of the cotton-tipped applicator, which rests on the mucosa just over the sphenopalatine ganglion at the level of the middle turbinate. The trajectory of the needle should be toward the posterior clinoid. The needle is slowly advanced under fluoroscopic guidance into the pterygopalatine fossa below the maxillary nerve and in close proximity to the sphenopalatine ganglion (Fig. 6-4). The needle tip ultimately is visualized just under the lateral nasal mucosa, and its position can be confirmed by injecting 0.5 mL of contrast medium. Sensory stimulation is then applied to the needle at 0.5 V at a frequency of 50 Hz. If the needle is in the correct position, the patient experiences a buzzing sensation just behind the nose with no stimulation into the distribution of other areas innervated by the maxillary nerve, which is often perceived by the patient as a buzzing sensation in the upper teeth (see “Side Effects and Complications” for pitfalls in needle placement). After correct needle placement is confirmed, pulsed radiofrequency lesioning is performed for 90 seconds at 44°C. Often a second lesion and sometimes a third lesion is necessary to provide long-lasting relief. TABLE 6-1

Because of the highly vascular nature of the pterygopalatine fossa, significant facial hematoma may occur after radiofrequency lesioning of the sphenopalatine ganglion. Owing to the proximity of other nerves, misplacement of the radiofrequency needle can result in damage to the affected nerve with permanent neurologic deficit. Stimulation before lesioning can help detect needle misplacement by identification of specific stimulation patterns (Table 6-1). The stimulation associated with proper placement of the needle is felt at the root of the nose. If the needle is malpositioned in proximity to the maxillary division of the nerve, the stimulation is experienced in the upper teeth. Should this occur, the needle should be positioned more caudad. If the needle is malpositioned near the greater and lesser palatine nerves, the stimulation is experienced in the hard palate. Should this occur, the needle should be redirected more medially and posteriorly. Patients occasionally may experience significant orthostatic hypotension or bradycardia during stimulation of the sphenopalatine ganglion. This phenomenon is thought to be analogous to the oculocardiac reflex and can be prevented with atropine. Patients who undergo stimulation of the sphenopalatine ganglion should be monitored closely for orthostatic hypotension and bradycardia and initially allowed to ambulate only with assistance.

Identification of Specific Stimulation Patterns

Needle Position

Stimulation Pattern

Corrective Maneuver

Needle in proper position

Stimulation at base of nose

None

Needle in proximity to maxillary nerve

Stimulation in upper teeth

Redirect needle more caudad

Needle in proximity to greater and lesser palatine nerves

Stimulation in hard palate

Redirect needle more posteriorly

Clinical Pearls Clinical experience has shown that sphenopalatine ganglion block with local anesthetic is useful in aborting the acute attack of migraine or cluster headache. The simplicity of the transnasal approach lends itself to use at the bedside, in the emergency room, or in the pain clinic. Although cocaine is probably a superior topical anesthetic for use with this technique, the various political issues surrounding the use of controlled substances make another local anesthetic such as viscous lidocaine a more logical choice. If previous trauma or tumor precludes the use of the transnasal approach to sphenopalatine ganglion block, injection of

local anesthetic via the greater palatine foramen or the lateral approach represents a good alternative. Because of the proximity of the sphenopalatine ganglion to the maxillary nerve, care must be taken to avoid inadvertent neurolysis of the maxillary nerve when performing neurodestructive procedures on the sphenopalatine ganglion. Because of the ability to more accurately localize the sphenopalatine ganglion by stimulation, radiofrequency lesioning via the lateral approach represents probably the safest option if destruction of the sphenopalatine ganglion is desired.

24

SECTION I

HEAD

C H A P T E R

7

Greater and Lesser Occipital Nerve Block CPT-2015 Code Unilateral Bilateral Neurolytic

64405 64405-50 64640

Relative Value Units Unilateral Bilateral Neurolytic

8 12 20

nuchal ridge along with the occipital artery. It supplies the medial portion of the posterior scalp as far anterior as the vertex (Fig. 7-1). The lesser occipital nerve arises from the ventral primary rami of the second and third cervical nerves. The lesser occipital nerve passes superiorly along the posterior border of the sternocleidomastoid muscle, dividing into cutaneous branches that innervate the lateral portion of the posterior scalp and the cranial surface of the pinna of the ear (see Fig. 7-1).

TECHNIQUE INDICATIONS Occipital nerve block is useful in the diagnosis and treatment of occipital neuralgia. This technique is also useful in providing surgical anesthesia in the distribution of the greater and lesser occipital nerves for lesion removal and laceration repair. This simple technique may also be used to supplement general anesthesia for neurosurgical procedures involving the occipital region.

CLINICALLY RELEVANT ANATOMY The greater occipital nerve arises from fibers of the dorsal primary ramus of the second cervical nerve and to a lesser extent from fibers of the third cervical nerve. The greater occipital nerve pierces the fascia just below the superior

Landmark and Fluoroscopically Guided Technique The patient is placed in a sitting position with the cervical spine flexed and the forehead on a padded bedside table (Fig. 7-2). A total of 8 mL of local anesthetic is drawn up in a 12-mL sterile syringe. When occipital neuralgia or other painful conditions involving the greater and lesser occipital nerves are being treated, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The occipital artery is then palpated at the level of the superior nuchal ridge. After preparation of the skin with antiseptic solution, a 22-gauge, 11 2-inch needle is inserted just medial to the artery and is advanced perpendicularly until the needle approaches the periosteum of the underlying occipital bone (Fig. 7-3). A paresthesia may be

7

GREATER AND LESSER OCCIPITAL NERVE BLOCK

ABSTRACT

KEY WORDS

The greater occipital nerve arises from fibers of the dorsal primary ramus of the second cervical nerve and to a lesser extent from fibers of the third cervical nerve. It supplies the medial portion of the posterior scalp as far anterior as the vertex. The lesser occipital nerve arises from the ventral primary rami of the second and third cervical nerves. The lesser occipital nerve passes superiorly along the posterior border of the sternocleidomastoid muscle, dividing into cutaneous branches that innervate the lateral portion of the posterior scalp and the cranial surface of the pinna of the ear. Occipital nerve block is useful in the diagnosis and treatment of occipital neuralgia. This technique is also useful in providing surgical anesthesia in the distribution of the greater and lesser occipital nerves for lesion removal and laceration repair.

greater occipital nerve headache lesser occipital nerve occipital nerve block

24.e1

occipital neuralgia ultrasound-guided occipital nerve block

7

GREATER AND LESSER OCCIPITAL NERVE BLOCK

25

Greater occipital n. Sup. nuchal ridge Occipital a. Occipital a.

C1

Tendinous arch Mastoid process

Lesser occipital n. 2nd cervical n.

C2

Lesser occipital n.

Vertebral a. 3rd cervical n.

C3

Sternocleidomastoid m.

Trapezius m. Greater occipital n.

Figure 7-1

Anatomy of the occipital nerve. a., Artery; n., nerve.

Sensory distribution of greater occipital n. Sensory distribution of lesser occipital n.

Figure 7-2 For the greater and lesser occipital nerve block procedure, the patient is placed in a sitting position with the cervical spine flexed and the forehead on a padded bedside table. n., Nerve.

Splenius capitis m.

Figure 7-3

Needle position and trajectory for greater and lesser occipital nerve block. a., Artery; m., muscle n., nerve; Sup., superior.

elicited, and the patient should be warned of such. The needle is then redirected superiorly, and after gentle aspiration, 5 mL of solution is injected in a fanlike distribution, with care taken to avoid the foramen magnum, which is located medially (Fig. 7-4; see also Fig. 7-3). The lesser occipital nerve and a number of superficial branches of the greater occipital nerve are then blocked by directing the needle laterally and slightly inferiorly. After gentle aspiration, an additional 3 to 4 mL of solution is injected (Fig. 7-5; see also Fig. 7-3).

Figure 7-4

Needle tip in proximity to the greater occipital nerve.

26

SECTION I

HEAD

Occipital nerve Occipital artery

Nuchal line

Figure 7-7 Transverse ultrasound scan demonstrating the ovoid greater occipital nerve and the occipital artery.

Figure 7-5

Needle tip in proximity to the lesser occipital nerve.

Ultrasound-Guided Technique For ultrasound-guided blockade of the greater and lesser occipital nerves, the patient is placed in a sitting position with the cervical spine flexed and the forehead on a padded bedside table. A total of 8 mL of local anesthetic is drawn up in a 12-mL sterile syringe. When occipital neuralgia or other painful conditions involving the greater and lesser occipital nerves are being treated, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The nuchal ridge is identified by palpation and then the occipital artery is located by palpation. A high-frequency linear ultrasound transducer is then placed in the transverse position at the nuchal ridge at the point at which the pulsation of the occipital artery was identified (Fig. 7-6). Color Doppler imaging may be used if there is difficulty in locating the occipital artery (Fig. 7-7). The occipital nerve will be in close proximity

Figure 7-6 Proper transverse position of the high-frequency linear ultrasound transducer over the point of palpation of the occipital artery.

to the artery and will appear on the sonogram as a hypoechoic ovoid structure that does not compress when pressure is applied with the overlying ultrasound transducer (see Fig. 7-7). After the nerve is clearly identified, a 31 2-inch spinal needle is inserted at the medial border of the ultrasound transducer using an in-plane approach and is advanced toward the occipital nerve until the needle tip impinges on the periosteum of the occipital bone. The patient may experience a paresthesia in the distribution of the greater occipital nerve and should be warned of such before the needle is advanced. When the needle tip is in proximity to the greater occipital nerve, after careful aspiration, 4 mL of the solution is injected in a fanlike manner. The needle is removed and pressure is placed on the injection site to avoid hematoma formation. The greater occipital nerve can also be blocked at the point where it passes between the obliquus capitis inferior and semispinalis capitis muscles. The lesser occipital nerve and a number of superficial branches of the greater occipital nerve are then blocked by directing the needle laterally and slightly inferiorly. After gentle aspiration, an additional 3 to 4 mL of solution is injected (see Figs. 7-3 and 7-5)

SIDE EFFECTS AND COMPLICATIONS The scalp is highly vascular, and this, coupled with the fact that both nerves are in close proximity to arteries, means that the pain specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely, especially if bilateral nerve blocks are being performed. This vascularity and the proximity to the arterial supply give rise to an increased incidence of postblock ecchymosis and hematoma formation. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulants by using a 25- or 27-gauge needle, albeit with increased risk of hematoma, if the clinical situation indicates a favorable risk-to-benefit ratio. Application of cold packs for 20-minute periods after the block also decreases the amount of postprocedure pain and bleeding the patient may experience. As mentioned earlier, care must be taken to avoid inadvertent needle placement into the foramen magnum because the subarachnoid administration of local anesthetic in this region results in an immediate total spinal anesthesia.

A

B

Figure 7-8

Positron emission tomography/magnetic resonance images of an occipital tumor in a patient with occipital headaches. (From Kops ER, Herzog H: Errors in MR-based attenuation correction for brain imaging with PET/MR scanners. Nucl Instrum Methods Phys Res A 702:104107, 2013.)

Clinical Pearls The most common reason that greater and lesser occipital nerve block fails to relieve headache pain is that the headache syndrome being treated has been misdiagnosed as occipital neuralgia. In the author’s experience, occipital neuralgia is an infrequent cause of headaches and rarely occurs in the absence of trauma to the greater and lesser occipital nerves. More often, the patient with headaches involving the occipital region is, in fact, suffering from tension-type headaches. Tension-type headaches do not respond to occipital nerve blocks but are amenable to treatment with antidepressant compounds such as amitriptyline in conjunction with cervical steroid epidural nerve blocks. Therefore, the pain management specialist should

reconsider the diagnosis of occipital neuralgia in patients whose symptoms are consistent with occipital neuralgia but who fail to show a response to greater and lesser occipital nerve blocks. Any patient with headaches severe enough to require neural blockade as part of the treatment plan should undergo magnetic resonance imaging of the head to rule out unsuspected intracranial disease, which may mimic the clinical symptoms of occipital neuralgia (Fig. 7-8). Furthermore, cervical spine radiography should be considered to rule out congenital abnormalities such as Arnold-Chiari malformations that may be the hidden cause of the patient’s occipital headaches.

8

GREATER AND LESSER OCCIPITAL NERVE BLOCK: RADIOFREQUENCY LESIONING

C H A P T E R

27

8

Greater and Lesser Occipital Nerve Block: Radiofrequency Lesioning INDICATIONS

CPT-2015 Code Neurolytic Neurolytic-Bilateral

64640 64640-50

CLINICALLY RELEVANT ANATOMY

Relative Value Units Neurolytic

Radiofrequency lesioning of the occipital nerve block is useful in select patients who have experienced short-term relief with occipital nerve blocks performed using local anesthetic or steroid and have failed to respond to other conservative therapies.

20

The greater occipital nerve arises from fibers of the dorsal primary ramus of the second cervical nerve and to a lesser

8

GREATER AND LESSER OCCIPITAL NERVE BLOCK: RADIOFREQUENCY LESIONING

ABSTRACT

KEY WORDS

The greater occipital nerve arises from fibers of the dorsal primary ramus of the second cervical nerve and to a lesser extent from fibers of the third cervical nerve. It supplies the medial portion of the posterior scalp as far anterior as the vertex. The lesser occipital nerve arises from the ventral primary rami of the second and third cervical nerves. The lesser occipital nerve passes superiorly along the posterior border of the sternocleidomastoid muscle, dividing into cutaneous branches that innervate the lateral portion of the posterior scalp and the cranial surface of the pinna of the ear. Radiofrequency lesioning of the occipital nerve block is useful in select patients who have experienced short-term relief with occipital nerve blocks performed using local anesthetic or steroid and have failed to respond to other conservative therapies.

greater occipital nerve headache lesser occipital nerve occipital nerve block occipital neuralgia

27.e1

radiofrequency-destruction occipital nerve block radiofrequency lesioning of the occipital nerves

28

SECTION I

HEAD

Occipital a.

C1

Lesser occipital n. 2nd cervical n.

C2 C3

Vertebral a. 3rd cervical n.

Figure 8-2 Greater occipital n.

Figure 8-1

Anatomy of the greater and lesser occipital nerves. a., Artery; n., nerve.

extent from fibers of the third cervical nerve. The greater occipital nerve pierces the fascia just below the superior nuchal ridge along with the occipital artery. It supplies the medial portion of the posterior scalp as far anterior as the vertex (Fig. 8-1). The lesser occipital nerve arises from the ventral primary rami of the second and third cervical nerves. The lesser occipital nerve passes superiorly along the posterior border of the sternocleidomastoid muscle, dividing into cutaneous branches that innervate the lateral portion of the posterior scalp and the cranial surface of the pinna of the ear (see Fig. 8-1).

Needle tip in proximity to the greater occipital nerve.

nerve. Then 2 mL of 1% lidocaine is injected to provide analgesia. After adequate analgesia has been obtained, lesioning is performed using two to three 120-second cycles of pulsed radiofrequency waves at 42°C. The lesser occipital nerve and a number of superficial branches of the greater occipital nerve are then lesioned by redirecting the needle laterally and slightly inferiorly (Fig. 8-3). Sensory stimulation to confirm correct needle position is again carried out with a frequency of 50 Hz. An amplitude of no more than 0.5 V should be required. The patient should experience stimulation in the distribution of the lesser occipital nerve. Then 2 mL of 1%

TECHNIQUE The patient is placed in a sitting position with the cervical spine flexed and the forehead on a padded bedside table. A total of 4 mL of local anesthetic is drawn up in a 12-mL sterile syringe. The occipital artery is then palpated at the level of the superior nuchal ridge. After preparation of the skin with antiseptic solution, a 22-gauge, 10-cm insulated blunt curved needle with a 5- to 10-mm active tip is inserted through an introducer needle just medial to the artery and is advanced perpendicularly until the needle approaches the periosteum of the underlying occipital bone (Fig. 8-2). A paresthesia may be elicited, and the patient should be warned of such. After the needle is in satisfactory position, sensory stimulation to confirm correct needle position is carried out at a frequency of 50 Hz. An amplitude of no more than 0.5 V should be required. The patient should experience stimulation in the distribution of the greater occipital

Figure 8-3

Needle tip in proximity to the lesser occipital nerve.

lidocaine is injected to provide analgesia. After adequate analgesia has been obtained, lesioning is performed using two to three 120-second cycles of pulsed radiofrequency waves at 42°C.

SIDE EFFECTS AND COMPLICATIONS The vascularity and the proximity to the arterial supply in this region give rise to an increased incidence of postblock ecchymosis and hematoma formation. These

complications can be decreased if manual pressure is applied to the area of the block immediately after the procedure. Application of cold packs for 20-minute periods after the block also decreases the amount of postprocedure pain and bleeding the patient may experience. As mentioned earlier, care must be taken to avoid inadvertent needle placement into the foramen magnum because the subarachnoid administration of local anesthetic in this region results in an immediate total spinal anesthesia.

Clinical Pearls The most common reason that greater and lesser occipital nerve block fails to relieve headache pain is that the headache syndrome being treated has been misdiagnosed as occipital neuralgia. In my experience, occipital neuralgia is an infrequent cause of headaches and rarely occurs in the absence of trauma to the greater and lesser occipital nerves. More often, the patient with headaches involving the occipital region is in fact suffering from tension-type headaches. Tension-type headaches do not respond to occipital nerve blocks but are amenable to treatment with antidepressant compounds such as amitriptyline in conjunction with cervical steroid epidural nerve blocks. Therefore, the pain management specialist should

reconsider the diagnosis of occipital neuralgia in patients whose symptoms are consistent with occipital neuralgia but who fail to respond to greater and lesser occipital nerve blocks. As with all neurodestructive procedures, the pain management specialist should be sure that the patient fully understands that the numbness experienced after the block may be permanent and that there is no guarantee that the procedure will relieve the patient’s pain. Any patient with headaches severe enough to require neural blockade as part of the treatment plan should undergo magnetic resonance imaging of the head to rule out unsuspected intracranial disease, which may mimic the clinical symptoms of occipital neuralgia.

9

GASSERIAN GANGLION BLOCK

C H A P T E R

29

9

Gasserian Ganglion Block CPT-2015 Code Unilateral Neurolytic

64400 64605 61790 (with radiographic guidance)

Relative Value Units Unilateral Neurolytic

15 30

INDICATIONS Gasserian ganglion block may be used as a part of the diagnostic evaluation of facial pain when the pain management specialist is trying to determine whether a patient’s pain is somatic or sympathetic in origin. In addition

to being used in anatomic differential neural blockade, gasserian ganglion block may be used in a prognostic manner before neurodestruction of the gasserian ganglion. Gasserian ganglion block also may be used in the acute setting to provide palliation in acute pain emergencies, including trigeminal neuralgia and cancer pain, during the wait for pharmacologic and antiblastic agents to become effective. Neurodestructive procedures of the gasserian ganglion using neurolytic agents, radiofrequency lesioning, balloon compression, or freezing may be indicated for palliation of cancer pain, including pain associated with invasive tumors of the orbit, maxillary sinus, and mandible. Destructive techniques also may be useful in the management of trigeminal neuralgia in patients for whom pharmacologic treatment, as well as nerve blocks with local anesthetic and steroid, has been ineffective and who are not considered candidates for more definitive neurosurgical procedures,

9

GASSERIAN GANGLION BLOCK

ABSTRACT

KEY WORDS

The gasserian ganglion is canoe shaped, with the three sensory divisions—the ophthalmic (V1), the maxillary (V2), and the mandibular (V3)—exiting the anterior convex aspect of the ganglion. A small motor root joins the mandibular division as it exits the cranial cavity through the foramen ovale. Gasserian ganglion block may be used as a part of the diagnostic evaluation of facial pain when the pain management specialist is trying to determine whether a patient’s pain is somatic or sympathetic in origin. In addition to being used in anatomic differential neural blockade, gasserian ganglion block may be used in a prognostic manner before neurodestruction of the gasserian ganglion. Gasserian ganglion block also may be used in the acute setting to provide palliation in acute pain emergencies, including trigeminal neuralgia and cancer pain, during the wait for pharmacologic and antiblastic agents to become effective. Neurodestructive procedures of the gasserian ganglion using neurolytic agents, radiofrequency lesioning, balloon compression, or freezing may be indicated for palliation of cancer pain, including pain associated with invasive tumors of the orbit, maxillary sinus, and mandible.

balloon compression gasserian ganglion gasserian ganglion block mandibular nerve maxillary nerve

29.e1

ophthalmic division retrogasserian glycerol trigeminal nerve trigeminal neuralgia

30

SECTION I

HEAD

including microvascular decompression (Jannetta’s procedure). Destruction of the gasserian ganglion has also been used in the management of intractable cluster headache and ocular pain secondary to persistent glaucoma.

II SC-CA PCA Tentorial edge

CLINICALLY RELEVANT ANATOMY

DR PR III V1

The gasserian ganglion is formed from two roots that exit the ventral surface of the brain stem at the midpontine level. These roots pass in a forward and lateral direction in the posterior cranial fossa across the border of the petrous bone. They then enter a recess called Meckel’s cave, which is formed by an invagination of the surrounding dura mater into the middle cranial fossa (Fig. 9-1). The dural pouch that lies just behind the ganglion is called the trigeminal cistern and contains cerebrospinal fluid (CSF). The gasserian ganglion is canoe shaped, with the three sensory divisions—the ophthalmic (V1), the maxillary (V2), and the mandibular (V3)—exiting the anterior convex aspect of the ganglion (Fig. 9-2). A small motor root joins the mandibular division as it exits the cranial cavity through the foramen ovale.

TECHNIQUE Landmark Technique The patient is placed in the supine position with the cervical spine extended over a rolled towel. About 2.5 cm lateral to the corner of the mouth, the skin is prepared with antiseptic solution, and sterile drapes are placed (Fig. 9-3). The skin and subcutaneous tissues are then anesthetized with 1% lidocaine with epinephrine.

V2 V3 MMA

Figure 9-1 Dissection demonstrating the anatomy about Meckel’s cave. The gasserian ganglion is well defined with the three major sensory branches clearly dissected. Cranial nerves II, III, IV, V1, V2, and V3 are marked. DR, Dural ring; MMA, middle meningeal artery; PCA, posterior cerebral artery; PR, proximal ring; SC-CA, supraclinoid carotid artery. (From Post KD, Meyer SA: Other schwannomas of cranial nerves. In Kaye AH, Laws ER Jr, editors: Brain Tumors, 3rd ed. Edinburgh, Saunders, 2012, pp 570-587.)

A 20-gauge, 13-cm styletted needle is advanced through the anesthetized area, traveling perpendicular to the pupil of the eye (when the eye is looking straight ahead). The trajectory of the needle is cephalad toward the acoustic auditory meatus. The needle is advanced until contact is made with the base of the skull (Fig. 9-4). The needle is withdrawn slightly and is “walked” posteriorly into the foramen ovale (Fig. 9-5). Paresthesia of the mandibular

V2, Maxillary division V1, Ophthalmic division

Frontal n.

Gasserian ganglion

Supratrochlear n. Supraorbital n.

Infraorbital n.

Mental n. V3, Mandibular division

Lingual n. Inf. alveolar n.

Figure 9-2

Anatomy of the gasserian ganglion and the divisions of the trigeminal nerve. Inf., Inferior; n., nerve.

9

GASSERIAN GANGLION BLOCK

31

nerve will probably be elicited as the needle enters the foramen ovale, and the patient should be warned of such.

Fluoroscopically Guided Technique

2.5 cm

Figure 9-3

For gasserian ganglion block, the needle is inserted 2.5 cm lateral to the corner of the mouth.

When gasserian ganglion block is performed under fluoroscopic guidance, the foramen ovale is identified on submental and oblique views (Fig. 9-6). The needle is then advanced under fluoroscopic guidance as described previously toward the foramen ovale. If the base of the skull is encountered, the needle is redirected into the foramen ovale (Figs. 9-7 and 9-8). After the needle enters the foramen ovale, the needle stylet is removed. A free flow of CSF is usually observed. If no CSF is observed, the needle tip is probably anterior to the trigeminal cistern but still may be within Meckel’s cave. Needle position can be confirmed by injecting 0.1-mL increments of preservative-free 1% lidocaine and observing the clinical response. Alternatively, 0.1 to 0.4 mL of contrast medium suitable for central nervous system use may be administered under fluoroscopic guidance before injection of the neurolytic substance (Fig. 9-9). Sterile glycerol, 6.5% phenol in glycerin, and absolute alcohol all have been successfully used for neurolysis of the gasserian ganglion. The neurolytic agent should be administered in 0.1-mL increments, with time allotted between additional increments to allow for observation of the clinical response. If hyperbaric neurolytic solutions such as glycerol or phenol in glycerin are used, the patient should be moved to the sitting position with the chin on the chest before injection (Fig. 9-10). This ensures that

Needle entry point

Foramen ovale V1

V2

Infratemporal surface Coronoid notch V3

Figure 9-4

A 20-gauge, 13-cm styletted needle is advanced through the anesthetized area, traveling perpendicular to the pupil of the eye (when the eye is looking straight ahead). The trajectory of the needle is cephalad toward the acoustic auditory meatus. The needle is advanced until contact is made with the base of the skull.

32

SECTION I

HEAD Needle entry point

Foramen ovale V1

V2

Coronoid notch Gasserian ganglion

V3

Figure 9-5

After the needle makes contact with the base of the skull, the needle is withdrawn slightly and is “walked” posteriorly into the foramen ovale. Paresthesia of the mandibular nerve will probably be elicited as the needle enters the foramen ovale, and the patient should be warned of such.

Foramen ovale

Angle of mandible

Figure 9-6

Foramen ovale.

Figure 9-7

Anteroposterior view of needle through the foramen ovale.

9

Figure 9-8

GASSERIAN GANGLION BLOCK

33

Lateral view of needle through the foramen ovale.

Figure 9-9 Contrast medium outlining Meckel’s cave. (From Waldman SD: Interventional Pain Management, 2nd ed. Philadelphia, Saunders, 2001, p 320.)

Pooling of hyperbaric neurolytic solution Foramen ovale

V1

V3

Figure 9-10

V2

If hyperbaric neurolytic solutions such as glycerol or phenol in glycerin are used when performing gasserian ganglion block, the patient should be moved to the sitting position with the chin on the chest before injection. This ensures that the solution is placed primarily around the maxillary and mandibular divisions and avoids the ophthalmic division.

34

SECTION I

HEAD

SIDE EFFECTS AND COMPLICATIONS

Figure 9-11

Patient with severe neuropathic pain in the territory of the inferior alveolar nerve (trigeminal V3) after dental surgery. First, a high cervical lead (Medtronic Resume) was applied for stimulation of the trigeminal spinal nucleus and tract at the C1-C2 level, and in addition, a deep brain stimulation (DBS) lead (Medtronic model 3389) shown here was used as a trial electrode for the retrogasserian rootlet. (From Van Buyten JP, Linderoth B: Invasive neurostimulation in facial pain and headache syndromes. Eur J Pain Suppl 5[2]:409-421, 2011.)

the solution is placed primarily around the maxillary and mandibular divisions and avoids the ophthalmic division. The patient should be left in the supine position if absolute alcohol is used. This same approach to the gasserian ganglion may be used to place radiofrequency needles, cryoprobes, compression balloons, and stimulating electrodes (Fig. 9-11).

A Figure 9-12

Because of the highly vascular nature of the pterygopalatine space, as well as its proximity to the middle meningeal artery, significant hematoma of the face and subscleral hematoma of the eye are common sequelae to gasserian ganglion block. The ganglion lies within the central nervous system, and small amounts of local anesthetic injected into the CSF may lead to total spinal anesthesia. For this reason, it is imperative that small, incremental doses of local anesthetic be injected, with time allowed after each dose to observe the effect of prior doses. Because of the potential for anesthesia of the ophthalmic division with its attendant corneal anesthesia, corneal sensation should be tested with a cotton wisp after gasserian ganglion block with either local anesthetic or neurolytic solution. If corneal anesthesia is present, sterile ophthalmic ointment should be used and the affected eye patched to avoid damage to the anesthetic cornea. This precaution must be continued for the duration of corneal anesthesia. Ophthalmologic consultation is advisable should persistent corneal anesthesia occur. Postprocedure dysesthesia, including anesthesia dolorosa, occurs in about 6% of patients who undergo neurodestructive procedures of the gasserian ganglion. These dysesthesias can range from mild pulling or burning sensations to severe postprocedure pain called anesthesia dolorosa. These postprocedure symptoms are thought to be due to incomplete destruction of the ganglion. Sloughing of skin in the area of anesthesia also may occur. In addition to disturbances of sensation, blockade or destruction of the gasserian ganglion may result in abnormal motor function, including weakness of the muscles of mastication and facial asymmetry. Horner’s syndrome also may occur as a result of block of the parasympathetic trigeminal fibers. The patient should be warned that all these complications may occur.

B

Herpes labialis can occur following gasserian ganglion block. (From Sapp JP, Eversole LR, Wysocki GP: Oral infections. In Contemporary Oral and Maxillofacial Pathology, 2nd ed. St Louis, Mosby, 2004, pp 207-251.)

9

A

Figure 9-13 A, Gadoliniumenhanced sagittal magnetic resonance image (MRI) of a dumbbellshaped tumor showing areas of decreased attenuation representing either necrosis or cystic degeneration. B, Gadolinium-enhanced axial MRI of a dumbbell-shaped tumor with extension through Meckel’s cave and some erosion of the posterior clinoid. C, Gadoliniumenhanced coronal MRI of the relatively homogenously enhancing mass with cystic components. D, Intraoperative photograph demonstrating a right trigeminal schwannoma in the middle cranial fossa. E, Intraoperative photograph demonstrating a preserved mandibular division of the trigeminal nerve after resection of the schwannoma seen in D. (From Post KD, Meyer SA: Other schwannomas of cranial nerves. In Kaye AH, Laws ER Jr, editors: Brain Tumors, 3rd ed. Edinburgh, Saunders, 2012, pp 570-587.)

GASSERIAN GANGLION BLOCK

35

B

D

C

E

Clinical Pearls Gasserian ganglion block with local anesthetic represents an excellent stopgap measure for patients suffering the uncontrolled pain of trigeminal neuralgia and cancer pain while waiting for pharmacologic and antiblastic treatments to take effect. This block has more side effects and complications than the usual nerve block modalities used by the pain management specialist and thus should be reserved for those special situations in which the pain is truly out of control. An interesting side effect of gasserian ganglion block is the activation of herpes labialis and, occasionally, of herpes zoster after the procedure (Fig. 9-12). This occurs in about 10% of patients who undergo procedures on the gasserian ganglion, and patients should be forewarned of this possibility. As mentioned previously, bleeding complications are not uncommon, and given the dramatic and highly visible nature of a facial and subscleral hematoma, all patients undergoing

gasserian ganglion block should be warned to expect this side effect to prevent undue anxiety should bleeding complications occur. Infection, although rare, remains an ever-present possibility, especially in the immunocompromised patient. Early detection of infection is crucial to avoid potentially lifethreatening sequelae. The pain management specialist should be particularly careful to identify and treat postprocedure corneal anesthesia. Failure to do so can often result in loss of vision. If persistent corneal anesthesia occurs, immediate ophthalmologic consultation should be obtained to manage any eye-related problems. As with all patients suffering from pain subserved by the trigeminal nerve and its branches, the clinician must be careful to identify the cause of the pain to avoid clinical disasters (Fig. 9-13).

C H A P T E R

10

Gasserian Ganglion Block: Radiofrequency Lesioning TECHNIQUE

CPT-2015 Code Neurolytic

64610 (with radiographic guidance)

Relative Value Units Neurolytic

30

INDICATIONS Neurodestructive procedures of the gasserian ganglion using neurolytic agents, radiofrequency lesioning, balloon compression, or freezing may be indicated for palliation of cancer pain, including pain associated with invasive tumors of the orbit, maxillary sinus, and mandible (Fig. 10-1). Destructive techniques also may be useful in the management of trigeminal neuralgia in patients for whom pharmacologic treatment, as well as nerve blocks with local anesthetic and steroid, has been ineffective and who are not considered candidates for more definitive neurosurgical procedures, including microvascular decompression (Jannetta’s procedure). Destruction of the gasserian ganglion has also been used in the management of intractable cluster headache and ocular pain secondary to persistent glaucoma. In recent years, radiofrequency lesioning has supplanted the use of neurolytic agents as the preferred method of destruction of the gasserian ganglion if the patient is not a suitable candidate for more definitive neurosurgical treatment.

The patient is placed in the supine position with the cervical spine extended over a rolled towel. About 2.5 cm lateral to the corner of the mouth, the skin is prepared with antiseptic solution and sterile drapes are placed. The skin and subcutaneous tissues are then anesthetized with 1% lidocaine with epinephrine. A 22-gauge, 15-cm insulated blunt curved needle with a 5- to 10-mm active tip is inserted through an introducer needle placed through the previously anesthetized area traveling perpendicular to the pupil of the eye (when the eye is looking straight ahead). The trajectory of the needle is cephalad toward the acoustic auditory meatus. The foramen ovale is identified on submental and oblique

A

CLINICALLY RELEVANT ANATOMY The gasserian ganglion is formed from two roots that exit the ventral surface of the brain stem at the midpontine level. These roots pass in a forward and lateral direction in the posterior cranial fossa across the border of the petrous bone. They then enter a recess called Meckel’s cave, which is formed by an invagination of the surrounding dura mater into the middle cranial fossa. The dural pouch that lies just behind the ganglion is called the trigeminal cistern and contains cerebrospinal fluid (CSF). The gasserian ganglion is canoe shaped, with the three sensory divisions—the ophthalmic (V1), the maxillary (V2), and the mandibular (V3)—exiting the anterior convex aspect of the ganglion (Fig. 10-2). A small motor root joins the mandibular division as it exits the cranial cavity via the foramen ovale. 36

B Figure 10-1

Osteosarcoma originating from the lateral orbital wall (greater wing of the sphenoid) and temporal bone with extension into the temporal fossa in a 12-year-old girl with bilateral retinoblastoma in typical locations. (From Rodjan F, de Graaf P, Brisse HJ, et al: Second cranio-facial malignancies in hereditary retinoblastoma survivors previously treated with radiation therapy: clinic and radiologic characteristics and survival outcomes. Eur J Cancer 49[8]:1939-1947, 2013.)

10

GASSERIAN GANGLION BLOCK: RADIOFREQUENCY LESIONING

ABSTRACT

KEY WORDS

The gasserian ganglion is canoe shaped, with the three sensory divisions—the ophthalmic (V1), the maxillary (V2), and the mandibular (V3)—exiting the anterior convex aspect of the ganglion. A small motor root joins the mandibular division as it exits the cranial cavity through the foramen ovale. Gasserian ganglion block may be used as a part of the diagnostic evaluation of facial pain when the pain management specialist is trying to determine whether a patient’s pain is somatic or sympathetic in origin. In addition to being used in anatomic differential neural blockade, gasserian ganglion block may be used in a prognostic manner before neurodestruction of the gasserian ganglion. Gasserian ganglion block also may be used in the acute setting to provide palliation in acute pain emergencies, including trigeminal neuralgia and cancer pain, during the wait for pharmacologic and antiblastic agents to become effective. Neurodestructive procedures of the gasserian ganglion using neurolytic agents, radiofrequency lesioning, balloon compression, or freezing may be indicated for palliation of cancer pain, including pain associated with invasive tumors of the orbit, maxillary sinus, and mandible.

balloon compression gasserian ganglion gasserian ganglion block mandibular nerve maxillary nerve ophthalmic division

36.e1

radiofrequency destruction of the gasserian ganglion radiofrequency lesioning of the gasserian ganglion retrogasserian glycerol trigeminal nerve trigeminal neuralgia

10

GASSERIAN GANGLION BLOCK: RADIOFREQUENCY LESIONING

37

V2, Maxillary division V1, Ophthalmic division

Frontal n.

Gasserian ganglion

Supratrochlear n. Supraorbital n.

Infraorbital n.

Mental n. V3, Mandibular division

Lingual n.

Figure 10-2

Inf. alveolar n.

Anatomy of the gasserian ganglion and trigeminal nerves. Inf., Inferior; n., nerve.

views (Fig. 10-3). The needle is then advanced under fluoroscopic guidance as described previously toward the foramen ovale (Figs. 10-4 and 10-5). If the base of the skull is encountered, the needle is redirected into the foramen ovale (Figs. 10-6 and 10-7). If difficulty is encountered in placing the needle through the foramen ovale into Meckel’s cave, submental and oblique views may be beneficial (Figs. 10-8 and 10-9). Paresthesia of

the mandibular nerve probably will be elicited as the needle enters the foramen ovale, and the patient should be warned of such. Confirmation that the needle is properly placed can be obtained by needle stimulation at 2 Hz with 0.5 to 1.5 V, which should produce motor stimulation of the ipsilateral muscles of the lower mandible. If no motor

Foramen ovale

Angle of mandible

Figure 10-3

Foramen ovale.

Figure 10-4

foramen ovale.

Anteroposterior view of needle tip approaching the

38

SECTION I

Figure 10-5

HEAD

Lateral view of needle approaching the foramen ovale.

response is observed, the needle should be repositioned more medially. If the needle is in proximity to the first or second divisions of the gasserian ganglion, no motor response should be observed. A mild paresthesia in the division that is to be lesioned should then be elicited by stimulating at 50 to 100 Hz with 0.1 to 0.5 V. If higher voltages are required to stimulate a paresthesia, the needle should be repositioned. Careful aspiration for blood and CSF should then be carried out and the needle repositioned until blood is not present. If no CSF or blood

Figure 10-6

ovale.

Anteroposterior view of needle through the foramen

Figure 10-7

Lateral view of needle through the foramen ovale.

is present, 0.25 to 0.5 mL of 0.2% ropivacaine is then injected, and the patient is monitored closely for inadvertent intravascular or subarachnoid injection. After 60 seconds, radiofrequency lesioning is carried out at 60°C for 90 seconds. Care should be taken to verify that the lesion has not produced corneal anesthesia.

SIDE EFFECTS AND COMPLICATIONS Because of the highly vascular nature of the pterygopalatine space as well as its proximity to the middle meningeal

Figure 10-8

Submental view of needle through the foramen ovale.

10

GASSERIAN GANGLION BLOCK: RADIOFREQUENCY LESIONING

39

Postprocedure dysesthesia, including anesthesia dolorosa, occurs in about 6% of patients who undergo neurodestructive procedures of the gasserian ganglion. These dysesthesias can range from mild pulling or burning sensations to severe postprocedure pain called anesthesia dolorosa. These postprocedure symptoms are thought to be due to incomplete destruction of the ganglion. Sloughing of skin in the area of anesthesia also may occur. In addition to disturbances of sensation, blockade or destruction of the gasserian ganglion may result in abnormal motor function, including weakness of the muscles of mastication and facial asymmetry. Horner’s syndrome also may occur as a result of block of the parasympathetic trigeminal fibers. The patient should be warned that all these complications may occur. Clinical Pearls

Figure 10-9

Needle properly placed in the foramen ovale.

artery, significant hematoma of the face and subscleral hematoma of the eye are common sequelae to gasserian ganglion block. The ganglion lies within the central nervous system, and small amounts of local anesthetic injected into the CSF may lead to total spinal anesthesia. For this reason, it is imperative that small doses of local anesthetic be injected, with time allowed after each dose to observe the effect of prior doses. Because of the potential for anesthesia of the ophthalmic division with its attendant corneal anesthesia, corneal sensation should be tested with a cotton wisp after lesioning of the gasserian ganglion. If corneal anesthesia is present, sterile ophthalmic ointment should be used and the affected eye patched to avoid damage to the cornea. This precaution must be continued for the duration of corneal anesthesia. Ophthalmologic consultation is advisable should persistent corneal anesthesia occur.

Gasserian ganglion block with local anesthetic represents an excellent stopgap measure for patients suffering the uncontrolled pain of trigeminal neuralgia and cancer pain while waiting for pharmacologic and antiblastic treatments to take effect. This block has more side effects and complications than the usual nerve block modalities used by the pain management specialist and thus should be reserved for those special situations in which the pain is truly out of control. An interesting side effect of gasserian ganglion block is the activation of herpes labialis and, occasionally, of herpes zoster after the procedure. This occurs in about 10% of patients who undergo procedures on the gasserian ganglion, and patients should be forewarned of this possibility. As mentioned previously, bleeding complications are not uncommon, and given the dramatic and highly visible nature of a facial and subscleral hematoma, all patients undergoing gasserian ganglion block should be warned to expect this side effect to prevent undue anxiety should bleeding complications occur. Infection, although rare, remains an ever-present possibility, especially in the immunocompromised patient. Early detection of infection is crucial to avoid potentially lifethreatening sequelae. The pain management specialist should be particularly careful to identify and treat postprocedure corneal anesthesia. Failure to do so can often result in loss of vision. If persistent corneal anesthesia occurs, immediate ophthalmologic consultation should be obtained to manage any eyerelated problems.

C H A P T E R

11

Gasserian Ganglion Block: Balloon Compression Technique CPT-2015 Code Neurolytic

64610 (with radiographic guidance)

TECHNIQUE

Relative Value Units Neurolytic

35

INDICATIONS Neurodestructive procedures of the gasserian ganglion using neurolytic agents, radiofrequency lesioning, balloon compression, or freezing may be indicated for palliation of cancer pain, including pain associated with invasive tumors of the orbit, maxillary sinus, and mandible. Destructive techniques also may be useful in the management of trigeminal neuralgia in patients for whom pharmacologic treatment, as well as nerve blocks with local anesthetic and steroid, has been ineffective and who are not considered candidates for more definitive neurosurgical procedures, including microvascular decompression (Jannetta’s procedure). Destruction of the gasserian ganglion has also been used in the management of intractable cluster headache and ocular pain secondary to persistent glaucoma. Balloon compression of the gasserian ganglion is a reasonable choice if the patient is not a suitable candidate for more definitive neurosurgical treatment. This technique has the added advantage of being performed completely under general anesthesia, which makes it ideal for the patient who is unwilling or unable to cooperate with the other percutaneous neurodestructive procedures on the gasserian ganglion, which require patient participation.

CLINICALLY RELEVANT ANATOMY The gasserian ganglion is formed from two roots that exit the ventral surface of the brain stem at the midpontine level. These roots pass in a forward and lateral direction in the posterior cranial fossa across the border of the petrous bone. They then enter a recess called Meckel’s cave, which is formed by an invagination of the surrounding dura mater into the middle cranial fossa. The dural pouch that lies just behind the ganglion is called the trigeminal cistern and contains cerebrospinal fluid (CSF). The gasserian ganglion is canoe shaped, with the three sensory divisions—the ophthalmic (V1), the maxillary (V2), and the mandibular (V3)—exiting the anterior 40

convex aspect of the ganglion (Fig. 11-1). A small motor root joins the mandibular division as it exits the cranial cavity through the foramen ovale.

The patient is placed in the supine position with the cervical spine extended over a rolled towel. About 2.5 cm lateral to the corner of the mouth, the skin is prepared with antiseptic solution, and sterile drapes are placed. The skin and subcutaneous tissues are then anesthetized with 1% lidocaine with epinephrine. An 18-gauge styletted spinal needle is used as an introducer needle and is placed through the previously anesthetized area traveling perpendicular to the pupil of the eye (when the eye is looking straight ahead). The trajectory of the needle is cephalad toward the acoustic auditory meatus. The foramen ovale is then identified on submental and oblique views (Fig. 11-2). A 22-gauge sterile K-wire is then placed through the spinal needle and advanced carefully to the foramen ovale. Proper placement of the K-wire just inside the foramen ovale is confirmed with fluoroscopy. An outer cannula is then passed over the K-wire into Meckel’s cave. After satisfactory placement of the outer cannula is confirmed with fluoroscopy, a 4-mm Fogarty catheter is placed through the cannula carefully into Meckel’s cave. After satisfactory placement of the Fogarty catheter is confirmed with fluoroscopy, the balloon is inflated with 0.7 mL of contrast medium for a period of 2 minutes. A pear-shaped image should be observed conforming to the internal bony constraints of Meckel’s cave. A failure to observe this pear shape means that the patient has a capacious Meckel’s cave and a larger Fogarty catheter will be required (Figs. 11-3, 11-4, and 11-5). If the gasserian ganglion is not completely compressed because the Fogarty catheter is of inadequate size, then little or no pain relief will result. Occasionally, two balloons are required to completely fill Meckel’s cave and fully compress the gasserian ganglion. After a 2-minute compression period, the Fogarty balloon catheter is deflated and, along with the introducer cannula, is removed. The patient is then observed for postoperative bleeding.

SIDE EFFECTS AND COMPLICATIONS Because of the highly vascular nature of the pterygopalatine space, as well as its proximity to the middle meningeal artery, significant hematoma of the face and subscleral

11 GASSERIAN GANGLION BLOCK: BALLOON COMPRESSION TECHNIQUE

ABSTRACT

KEY WORDS

The gasserian ganglion is canoe shaped, with the three sensory divisions—the ophthalmic (V1), the maxillary (V2), and the mandibular (V3)—exiting the anterior convex aspect of the ganglion. A small motor root joins the mandibular division as it exits the cranial cavity through the foramen ovale. Gasserian ganglion block may be used as a part of the diagnostic evaluation of facial pain when the pain management specialist is trying to determine whether a patient’s pain is somatic or sympathetic in origin. In addition to being used in anatomic differential neural blockade, gasserian ganglion block may be used in a prognostic manner before neurodestruction of the gasserian ganglion. Gasserian ganglion block also may be used in the acute setting to provide palliation in acute pain emergencies, including trigeminal neuralgia and cancer pain, during the wait for pharmacologic and antiblastic agents to take effect. Neurodestructive procedures of the gasserian ganglion using neurolytic agents, radiofrequency lesions, balloon compression, or freezing may be indicated for palliation of cancer pain, including pain associated with invasive tumors of the orbit, maxillary sinus, and mandible.

balloon compression gasserian ganglion gasserian ganglion block mandibular nerve maxillary nerve ophthalmic division

40.e1

radiofrequency destruction of the gasserian ganglion radiofrequency lesioning of the gasserian ganglion retrogasserian glycerol trigeminal nerve trigeminal neuralgia

11 GASSERIAN GANGLION BLOCK: BALLOON COMPRESSION TECHNIQUE

41

V2, Maxillary division V1, Ophthalmic division

Frontal n.

Gasserian ganglion

Supratrochlear n. Supraorbital n.

Infraorbital n.

Mental n. V3, Mandibular division

Lingual n.

Figure 11-1

Inf. alveolar n.

Anatomy of the gasserian ganglion and trigeminal nerves. Inf., Inferior; n., nerve.

hematoma of the eye are common sequelae to gasserian ganglion block. The ganglion lies within the central nervous system, and small amounts of local anesthetic injected into the CSF may lead to total spinal anesthesia. For this reason, it is imperative that small doses of local anesthetic be injected, with time allowed after each dose to observe the effect of prior doses. Because of the potential for anesthesia of the ophthalmic division with its attendant corneal anesthesia,

corneal sensation should be tested with a cotton wisp after lesioning of the gasserian ganglion. If corneal anesthesia is present, sterile ophthalmic ointment should be used and the affected eye patched to avoid damage to the cornea. This precaution must be continued for the duration of corneal anesthesia. Ophthalmologic consultation is advisable should persistent corneal anesthesia occur. Postprocedure dysesthesia, including anesthesia dolorosa, occurs in about 6% of patients who undergo neurodestructive procedures of the gasserian ganglion. These dysesthesias can range from mild pulling or burning sensations to severe postprocedure pain called anesthesia

Foramen ovale

Angle of mandible

Figure 11-2

Foramen ovale.

Figure 11-3

Left to right: Different-sized outer cannulas with Nos. 3, 4, 5, and 6 inflated Fogarty balloons. (From Goerss SJ, Atkinson JLD, Kallmes DF: Variable size percutaneous balloon compression of the gasserian ganglion for trigeminal neuralgia. Surg Neurol 71[3]: 388-390, 2009.)

42

A

SECTION I

HEAD

B

Figure 11-4 A, A No. 4 Fogarty balloon maximally inflated for 2 minutes failed to produce any facial hypesthesia in this patient, with early recurrence of pain 9 months later. B, Repeat balloon compression using a No. 5 Fogarty balloon for 1 minute resulted in perioral hypesthesia and no pain recurrence in 5 years. (From Goerss SJ, Atkinson JLD, Kallmes DF: Variable size percutaneous balloon compression of the gasserian ganglion for trigeminal neuralgia. Surg Neurol 71[3]:388-390, 2009.)

A

B

Figure 11-5 A and B, Balloon compression in a patient with multiple sclerosis for whom previous radiofrequency and glycerol tests had failed (note tantalum powder behind balloon) and for whom all balloon compression procedures over a few months also had failed. A, The balloon depicted is a No. 6 Fogarty balloon that was held in place for 4 minutes. Note the lack of a pear-shaped configuration owing primarily to the large dimensions of Meckel’s cave. There was no facial hypesthesia, and the patient’s pain continued unabated. B, Two No. 4 Fogarty balloons were passed through separate cannulas. Both were inflated and held in place for 2 minutes, which resulted in perioral hypesthesia and excellent pain relief without medications. (From Goerss SJ, Atkinson JLD, Kallmes DF: Variable size percutaneous balloon compression of the gasserian ganglion for trigeminal neuralgia. Surg Neurol 71[3]:388-390, 2009.)

dolorosa. These postprocedure symptoms are thought to be due to incomplete destruction of the ganglion. Sloughing of skin in the area of anesthesia also may occur. In addition to disturbances of sensation, blockade or destruction of the gasserian ganglion may result in abnormal motor function, including weakness of the muscles

of mastication and facial asymmetry. Horner’s syndrome also may occur as a result of block of the parasympathetic trigeminal fibers. If the balloon is inadvertently placed too high and medial to Meckel’s cave, abducens palsy may result. The patient should be warned that all of these complications may occur.

Clinical Pearls Gasserian ganglion block with local anesthetic represents an excellent stopgap measure for patients suffering the uncontrolled pain of trigeminal neuralgia and cancer pain while waiting for pharmacologic and antiblastic treatments to take effect. This block has more side effects and complications than the usual nerve block modalities used by the pain management specialist and thus should be reserved for those special situations in which the pain is truly out of control. An interesting side effect of gasserian ganglion block is the activation of herpes labialis and, occasionally, of herpes zoster after the procedure. This occurs in about 10% of patients who undergo procedures on the gasserian ganglion, and patients should be forewarned of this possibility. As mentioned previously, bleeding complications are not uncommon, and given the dramatic and highly visible nature

of a facial and subscleral hematoma, all patients undergoing gasserian ganglion block should be warned to expect this side effect to prevent undue anxiety should bleeding complications occur. Infection, although rare, remains an ever-present possibility, especially in the immunocompromised patient. Early detection of infection is crucial to avoid potentially lifethreatening sequelae. The pain management specialist should be particularly careful to identify and treat postprocedure corneal anesthesia. Failure to do so can often result in loss of vision. If persistent corneal anesthesia occurs, immediate ophthalmologic consultation should be obtained to manage any eye-related problems.

12

TRIGEMINAL NERVE BLOCK: CORONOID APPROACH

C H A P T E R

43

12

Trigeminal Nerve Block: Coronoid Approach CPT-2015 Code Unilateral Neurolytic

64400 64605 64610 (with radiographic guidance)

Relative Value Units Unilateral Neurolytic

10 20

INDICATIONS Trigeminal nerve block through the coronoid approach is a simple and safe way to block the maxillary and mandibular divisions of the trigeminal nerve. This technique may be used as a part of the diagnostic evaluation of

facial pain when the pain management specialist is trying to determine whether a patient’s pain is somatic or sympathetic in origin. In addition to permitting anatomic differential neural blockade, trigeminal nerve block via the coronoid approach allows selective blockade of the maxillary and mandibular divisions, so the technique can also be used in a prognostic manner before neurodestruction of these nerves. Trigeminal nerve block through the coronoid approach also may be used in the acute setting to provide palliation in acute pain emergencies, including trigeminal neuralgia, facial trauma, and cancer pain, during the wait for pharmacologic and antiblastic agents to take effect. Trigeminal nerve block with local anesthetic may be used as a treatment for trismus and as an aid to awake intubation. Trigeminal nerve block with local anesthetic and steroid through the coronoid approach is also useful as a firstline treatment for the breakthrough pain of trigeminal

12

TRIGEMINAL NERVE BLOCK: CORONOID APPROACH

ABSTRACT

KEY WORDS

Trigeminal nerve block through the coronoid approach is used to block the maxillary and mandibular divisions of the trigeminal nerve. The maxillary division (V2) of the trigeminal nerve is a pure sensory nerve (Fig. 12-1). It exits the middle cranial fossa via the foramen rotundum and crosses the pterygopalatine fossa where it is amenable to blockade by trigeminal nerve block via the coronoid approach. The mandibular division (V3) is composed of a large sensory root and a smaller motor root. Both leave the middle cranial fossa together via the foramen ovale and join to form the mandibular nerve. The smaller motor branch provides innervation to the masseter, external pterygoid, and temporalis muscles. The technique of trigeminal nerve block via the coronoid approach can be used to perform diagnostic, prognostic, and therapeutic neural blockade of the maxillary and mandibular divisions of the trigeminal nerve.

cancer pain mandibular nerve maxillary nerve pterygopalatine fossa

trigeminal nerve trigeminal nerve block trigeminal neuralgia

43.e1

44

SECTION I

HEAD

neuralgia that has previously been controlled with medications. This technique can be used in the treatment of pain associated with acute herpes zoster and postherpetic neuralgia in the distribution of the trigeminal nerve. Atypical facial pain syndromes, including temporomandibular joint dysfunction, also may be amenable to treatment using this technique. Neurodestructive procedures of the maxillary and mandibular nerves using neurolytic agents, radiofrequency lesioning, or freezing may be carried out via the coronoid approach to the trigeminal nerve. These neurodestructive techniques are useful in the palliation of cancer pain, including pain secondary to invasive tumors of the maxillary sinus and mandible.

CLINICALLY RELEVANT ANATOMY The maxillary division (V2) of the trigeminal nerve is a pure sensory nerve (see Fig. 12-1). It exits the middle cranial fossa via the foramen rotundum and crosses the pterygopalatine fossa (Fig. 12-2). Passing through the inferior orbital fissure, it enters the orbit, emerging on the face via the infraorbital foramen. The maxillary nerve can be selectively blocked by placing a needle just above the anterior margin of the lateral pterygoid plate. The maxillary nerve provides sensory innervation for the dura of the middle cranial fossa, the temporal and lateral zygomatic region, and the mucosa of the maxillary sinus. The nerve also provides sensory innervation for the upper molars, premolars, incisors, canines, and associated oral gingiva as well as the mucous membranes of the cheek. The nasal cavity, lower eyelid, skin of the side of

V1

M L 1

2 G

Figure 12-2 T1-weighted image through the left face medial to the mandible, demonstrating the maxillary sinus (M), orbital surface of the maxilla (open white arrow), medial aspect of the pterygopalatine fossa (white arrowhead), retroantral fat pad (solid white arrow), lateral pterygoid muscle fibers coursing to the proximal mandible (L), marrow in the maxilla (solid white arrow 1) and mandible (solid white arrow 2), sublingual space (top black arrow), geniohyoid muscle (G), and hyoid bone (bottom black arrow). (From Stark DD, Bradley WG: Magnetic Resonance Imaging, 3rd ed. St Louis, Mosby, 1999, p 1747.) the nose, and upper lip are also subserved by the maxillary nerve. The mandibular division (V3) is composed of a large sensory root and a smaller motor root. Both leave the middle cranial fossa together via the foramen ovale and join to form the mandibular nerve. Branches of the mandibular nerve provide sensory innervation to portions of the dura mater and the mucosal lining of the mastoid sinus. Sensory innervation to the skin overlying the muscles of mastication, the tragus and helix of the ear, the posterior temporomandibular joint, the chin, and the dorsal aspect of the anterior two thirds of the tongue and associated mucosa of the oral cavity is also provided by the mandibular nerve (see Fig. 12-1). The smaller motor branch provides innervation to the masseter, external pterygoid, and temporalis muscles.

TECHNIQUE Landmark and Fluoroscopically Guided Technique V2

V3

V1, Ophthalmic nerve V2, Maxillary nerve V3, Mandibular nerve

Figure 12-1

The divisions of the trigeminal nerve.

The patient is placed in the supine position with the cervical spine in the neutral position. The coronoid notch is identified by asking the patient to open and close the mouth several times and palpating the area just anterior and slightly inferior to the acoustic auditory meatus. After the notch is identified, the patient is asked to hold his or her mouth in neutral position. A total of 7 mL of local anesthetic is drawn up in a 12-mL sterile syringe. When the treatment is for trigeminal neuralgia, atypical facial pain, or other painful conditions involving the maxillary and mandibular nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. After the skin overlying the coronoid notch is prepared with antiseptic solution, a 22-gauge, 31 2-inch styletted needle is inserted just below the zygomatic arch directly

12

TRIGEMINAL NERVE BLOCK: CORONOID APPROACH

45

Lateral pterygoid plate

Coronoid notch Mandible

Figure 12-3

Relationship of the coronoid notch and the lateral pterygoid plate (star).

in the middle of the coronoid notch (Fig. 12-3). The needle is advanced about 11 2 to 2 inches in a plane perpendicular to the skull until the lateral pterygoid plate is encountered (Fig. 12-4). At this point, if blockade of both the maxillary and mandibular nerves is desired, the needle is withdrawn slightly. After careful aspiration, 7 to 8 mL of solution is injected in incremental doses. The needle is removed and pressure is placed on the injection site to avoid ecchymosis. Fluoroscopic guidance may be used if the clinician has difficulty in identifying the coronoid notch (Fig. 12-5).

Figure 12-5 Fluoroscopic image demonstrating proper needle placement for trigeminal nerve block using the coronoid approach. During the injection procedure, the patient must be observed carefully for signs of local anesthetic toxicity. The coronoid approach to blockade of the trigeminal nerve may be used to place radiofrequency needles, cryoprobes, and stimulating electrodes.

Ultrasound-Guided Technique The coronoid notch is identified as described in the previous section. After the coronoid notch is identified, a

Lateral pterygoid plate

V2

Figure 12-4

For trigeminal nerve block using the coronoid approach, the needle is advanced through the coronoid notch into the pterygopalatine fossa.

Needle entry point

V3

Coronoid notch

46

SECTION I

HEAD

Superior Zygomatic arch

Masseter muscle Temporalis muscle Maxillary nerve

Posterior Mandible

Figure 12-7 Figure 12-6 Proper placement of a high-frequency liner ultrasound electrode over the coronoid notch. high-frequency linear ultrasound transducer is placed in a transverse position over the coronoid notch and a sonogram is taken (Fig. 12-6). The coronoid notch provides an acoustic window into the pterygopalatine fossa and allows easy identification of the maxillary nerve (Fig. 12-7). The temporomandibular joint should be identified in the posterior aspect of the sonogram by locating the ball-shaped mandibular condyle and the mandibular neck. Under realtime ultrasound guidance, a 22-gauge, 31 2-inch needle is inserted just below the zygomatic arch directly in the middle of the coronoid notch using an out-of-plane approach. The needle is advanced until it impinges on the lateral pterygoid plate. The tip of the needle is then withdrawn slightly out of the periosteum of the lateral pterygoid plate. After careful aspiration, 7 to 8 mL of local anesthetic and 40 to 80 mg of depot-steroid are injected in incremental doses. The needle is removed and pressure is placed on the injection sight to avoid ecchymosis.

SIDE EFFECTS AND COMPLICATIONS Because of the highly vascular nature of the pterygopalatine fossa, significant facial hematoma may occur after trigeminal nerve block via the coronoid approach. This vascularity means that the pain specialist should use small, incremental doses of local anesthetic to avoid local anesthetic toxicity. Postprocedure dysesthesia, including anesthesia dolorosa, may occur in a small number of patients who undergo neurodestructive procedures of the branches of the trigeminal nerve. These dysesthesias can range from mild

Transverse ultrasound image demonstrating the maxillary nerve and surrounding structures seen via the acoustic window provided by the coronoid notch.

pulling or burning sensations to severe postprocedure pain called anesthesia dolorosa. These postprocedure symptoms are thought to be due to incomplete destruction of the neural structures. Sloughing of skin in the area of anesthesia also may occur. In addition to disturbances of sensation, blockade or destruction of the branches of the trigeminal nerve may result in abnormal motor function, including weakness of the muscles of mastication and secondary facial asymmetry due to muscle weakness or loss of proprioception. The patient should be warned that all of these complications may occur. Clinical Pearls Trigeminal nerve block via the coronoid approach with local anesthetic and steroid represents an excellent stopgap measure for patients suffering from the uncontrolled pain of trigeminal neuralgia and cancer pain while waiting for pharmacologic treatments to take effect. The major side effects of this block are related to the vascular nature of the pterygopalatine fossa, and care must be taken to avoid local anesthetic toxicity. Despite this vascularity, this technique can be performed safely in patients receiving anticoagulatants by using a 25- or 27-gauge needle, albeit with increased risk of facial hematoma, if the clinical situation indicates a favorable risk-to-benefit ratio. Because repeated needle punctures with daily or everyother-day blocks may result in small punctate facial scars, patients should be warned of this possibility. Infection, although rare, remains an ever-present possibility, especially in the immunocompromised patient. Early detection of infection is crucial to avoid potentially life-threatening sequelae.

C H A P T E R

13

Selective Maxillary Nerve Block: Coronoid Approach CPT-2015 Code Unilateral Neurolytic

64400 64605 64610 (with radiographic guidance)

Relative Value Units Unilateral Neurolytic

10 20

INDICATIONS Trigeminal nerve block via the coronoid approach is a simple and safe way to block the maxillary and mandibular divisions of the trigeminal nerve. This technique may be used as a part of the diagnostic evaluation of facial pain when the pain management specialist is trying to determine whether a patient’s pain is somatic or sympathetic in origin. In addition to permitting anatomic

differential neural blockade, trigeminal nerve block via the coronoid approach allows selective blockade of the maxillary and mandibular divisions, so the technique can also be used in a prognostic manner before neurodestruction of these nerves. Procedures for neurodestruction of the maxillary and mandibular nerves by neurolytic agents, radiofrequency lesioning, or freezing may be carried out using selective maxillary and mandibular nerve block techniques. These neurodestructive techniques are useful in the palliation of cancer pain, including pain secondary to invasive tumors of the maxillary sinus and mandible.

CLINICALLY RELEVANT ANATOMY The maxillary division (V2) of the trigeminal nerve is a pure sensory nerve. It exits the middle cranial fossa via the foramen rotundum and crosses the pterygopalatine fossa (Fig. 13-1). Passing through the inferior orbital fissure, it enters the orbit, emerging on the face via the infraorbital foramen. The maxillary nerve can be selectively blocked V2, Maxillary division

V1, Ophthalmic division

Frontal n.

Gasserian ganglion

Supratrochlear n. Supraorbital n.

Infraorbital n.

Mental n. V3, Mandibular division

Figure 13-1

Anatomy of the gasserian ganglion and the trigeminal nerve. Inf., Inferior; n., nerve.

Lingual n. Inf. alveolar n.

47

13

SELECTIVE MAXILLARY NERVE BLOCK: CORONOID APPROACH

ABSTRACT

KEY WORDS

Trigeminal nerve block through the coronoid approach is used to block the maxillary and mandibular divisions of the trigeminal nerve. The maxillary division (V2) of the trigeminal nerve is a pure sensory nerve (see Fig. 13-2). It exits the middle cranial fossa via the foramen rotundum and crosses the pterygopalatine fossa where it is amenable to blockade via trigeminal nerve block via the coronoid approach. The mandibular division (V3) is composed of a large sensory root and smaller motor root. Both leave the middle cranial fossa together via the foramen ovale and join to form the mandibular nerve. The smaller motor branch provides innervation to the masseter, external pterygoid, and temporalis muscles. The technique of trigeminal nerve block via the coronoid approach can be used to perform diagnostic, prognostic, and therapeutic neural blockade of the maxillary and mandibular divisions of the trigeminal nerve. This approach allows selective blockade of the maxillary and mandibular divisions, so the technique can also be applied in a prognostic manner before neurodestruction of these nerves. Procedures for neurodestruction of the maxillary and mandibular nerves by neurolytic agents, radiofrequency lesions, or freezing may be carried out using selective maxillary and mandibular nerve block techniques.

cancer pain mandibular nerve mandibular nerve block maxillary nerve maxillary nerve block

pterygopalatine fossa trigeminal nerve trigeminal nerve block trigeminal neuralgia

47.e1

48

SECTION I

HEAD

V1

V2

V3

V1, Ophthalmic nerve V2, Maxillary nerve V3, Mandibular nerve

Figure 13-2

Divisions of the trigeminal nerve.

by placing a needle just above the anterior margin of the lateral pterygoid plate. The maxillary nerve provides sensory innervation for the dura of the middle cranial fossa, the temporal and lateral zygomatic region, and the mucosa of the maxillary sinus. The nerve also provides sensory innervation for the upper molars, premolars, incisors, canines, and associated oral gingiva as well as the mucous membranes of the cheek (Fig. 13-2). The nasal cavity, lower eyelid, skin of the side of the nose, and upper lip are also subserved by the maxillary nerve. The mandibular division (V3) is composed of a large sensory root and a smaller motor root. Both leave the middle cranial fossa together via the foramen ovale and join to form the mandibular nerve. Branches of the mandibular nerve provide sensory innervation to portions of the dura mater and the mucosal lining of the mastoid sinus. Sensory innervation to the skin overlying the muscles of mastication, the tragus and helix of the ear, the posterior temporomandibular joint, the chin, and the dorsal aspect of the anterior two thirds of the tongue and associated mucosa of the oral cavity is also provided by the mandibular nerve (see Fig. 13-2). The smaller motor branch provides innervation to the masseter, external pterygoid, and temporalis muscles.

identified by asking the patient to open and close the mouth several times and palpating the area just anterior and slightly inferior to the acoustic auditory meatus. After the notch is identified, the patient is asked to hold his or her mouth in neutral position. A total of 7 mL of local anesthetic is drawn up in a 12-mL sterile syringe. When the treatment is for trigeminal neuralgia, atypical facial pain, or other painful conditions involving the maxillary and mandibular nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. After the skin overlying the coronoid notch is prepared with antiseptic solution, a 22-gauge, 31 2-inch styletted needle is inserted just below the zygomatic arch directly in the middle of the coronoid notch. The needle is advanced about 11 2 to 2 inches in a plane perpendicular to the skull until the lateral pterygoid plate is encountered (Fig. 13-3). For selective blockade of the maxillary nerve, the styletted needle is withdrawn after it comes in contact with the lateral pterygoid plate and is redirected anteriorly and slightly superiorly so that it will slip past the anterior margin of the lateral pterygoid plate (Figs. 13-4 and 13-5). A paresthesia in the distribution of the maxillary nerve is usually elicited about 1 cm deeper than the point at which the lateral pterygoid plate was encountered, and the patient should be warned of such. After careful aspiration, 3 to 5 mL of solution is injected in incremental doses. During the injection procedure, the patient must be observed carefully for signs of local anesthetic toxicity. The technique for selective maxillary nerve block via the coronoid approach may be used to place

TECHNIQUE Landmark and Fluoroscopically Guided Technique The patient is placed in the supine position with the cervical spine in the neutral position. The coronoid notch is

Figure 13-3

Needle placed through the coronoid notch with tip resting against the lateral pterygoid plate.

13

SELECTIVE MAXILLARY NERVE BLOCK: CORONOID APPROACH

49

Maxillary nerve

Lateral pterygoid plate

Needle entry point

Coronoid notch

Figure 13-4

For selective blockade of the maxillary nerve, the styletted needle is withdrawn after it comes in contact with the lateral pterygoid plate and is redirected anteriorly and slightly superiorly so that it will slip past the anterior margin of the lateral pterygoid plate.

radiofrequency needles, cryoprobes, or stimulating electrodes (Fig. 13-6).

Ultrasound-Guided Technique The coronoid notch is identified as described in the previous section. After the coronoid notch is identified, a high-frequency linear ultrasound transducer is placed in

a transverse position over the coronoid notch and a sonogram is taken (Fig. 13-7). The coronoid notch provides an acoustic window into the pterygopalatine fossa and allows easy identification of the maxillary nerve (Fig. 13-8). The temporomandibular joint should be identified in the posterior aspect of the sonogram by locating the ball-shaped mandibular condyle and the mandibular neck. Under real-time ultrasound guidance, a 22-gauge, 31 2-inch needle is inserted just below the zygomatic arch directly in the middle of the coronoid notch using an out-of-plane approach. The needle is advanced until it impinges on the lateral pterygoid plate. The tip of the needle is then withdrawn slightly out of the periosteum of the lateral pterygoid plate and redirected toward the pupil of the eye until it slips past the anterosuperior margin of the lateral pterygoid plate into the pterygopalatine fissure and in proximity to the maxillary nerve. A paresthesia may be elicited, and the patient should be warned of such. After careful aspiration, 4 to 5 mL of local anesthetic and 40 to 80 mg of depot-steroid are injected in incremental doses. During the injection procedure, the patient must be observed carefully for signs of local anesthetic toxicity. Because of the proximity of the sphenopalatine ganglion, the patient may also experience partial blockade of this structure. The needle is removed and pressure is placed on the injection site to avoid ecchymosis.

SIDE EFFECTS AND COMPLICATIONS Figure 13-5

Needle in position in front of the anterior margin of the lateral pterygoid plate.

Because of the highly vascular nature of the pterygopalatine fossa, significant facial hematoma may occur after trigeminal nerve block via the coronoid approach. This vascularity means that the pain specialist should use

50

SECTION I

HEAD

Figure 13-6

Anteroposterior and lateral radiographs demonstrating neurostimulation of peripheral branches of the maxillary division of the trigeminal nerve to treat post-traumatic maxillary neuralgia. (From Van Buyten JP, Linderoth B: Invasive neurostimulation in facial pain and headache syndromes. Eur J Pain Suppl 5[2]:409421, 2011.)

Figure 13-7

Proper transverse location of the high-frequency linear ultrasound transducer for needle placement via the coronoid notch to block the maxillary nerve.

small, incremental doses of local anesthetic to avoid local anesthetic toxicity. Postprocedure dysesthesia, including anesthesia dolorosa, may occur in a small number of patients who undergo neurodestructive procedures of the branches of the trigeminal nerve. These dysesthesias can range from mild pulling or burning sensations to severe postprocedure pain called anesthesia dolorosa. These postprocedure symptoms are thought to be due to incomplete destruction of the neural structures. Sloughing of skin in the area of anesthesia also may occur. In addition to disturbances of sensation, blockade or destruction of the branches of the trigeminal nerve may result in abnormal motor function, including weakness of the muscles of mastication and secondary facial asymmetry due to muscle weakness or loss of proprioception. The patient should be warned that all of these complications may occur.

Masseter Zygomatic arch Temporalis Mandibular neck

Maxillary n

Sphenopalatine ganglion

Figure 13-8 Ultrasound image through the acoustic window provided by the coronoid notch demonstrating the maxillary nerve. Note the proximity of the sphenopalatine ganglion. n, Nerve.

Clinical Pearls Trigeminal nerve block via the coronoid approach with local anesthetic and steroid represents an excellent stopgap measure for patients suffering from the uncontrolled pain of trigeminal neuralgia, acute herpes zoster, and cancer pain while waiting for pharmacologic treatments to take effect. The major side effects of this block are related to the vascular nature of the pterygopalatine fossa, and care must be taken to avoid local anesthetic toxicity. Despite this vascularity, this technique can be performed safely in patients receiving anticoagulant therapy

by using a 25- or 27-gauge needle, albeit at increased risk of facial hematoma, should the clinical situation indicate a favorable risk-to-benefit ratio. Because repeated needle punctures with daily or everyother-day blocks may result in small punctate facial scars, patients should be warned of this possibility. Infection, although rare, remains an ever-present possibility, especially in the immunocompromised patient. Early detection of infection is crucial to avoid potentially life-threatening sequelae.

14

SELECTIVE MANDIBULAR NERVE BLOCK: CORONOID APPROACH

C H A P T E R

51

14

Selective Mandibular Nerve Block: Coronoid Approach CPT-2015 Code Unilateral Neurolytic

64400 64605 64610 (with radiographic guidance)

Relative Value Units Unilateral Neurolytic

10 20

INDICATIONS Trigeminal nerve block via the coronoid approach is a simple and safe way to block the maxillary and mandibular divisions of the trigeminal nerve. This technique may be used as a part of the diagnostic evaluation of facial pain when the pain management specialist is trying to determine whether a patient’s pain is somatic or sympathetic in origin. In addition to permitting anatomic differential neural blockade, trigeminal nerve block via the coronoid approach allows selective blockade of the maxillary and mandibular divisions, so the technique can also be used in a prognostic manner before neurodestruction of these nerves. Procedures for neurodestruction of the maxillary and mandibular nerves by neurolytic agents, radiofrequency lesioning, or freezing may be carried out using selective maxillary and mandibular nerve block techniques. These

neurodestructive techniques are useful in the palliation of cancer pain, including pain secondary to invasive tumors of the maxillary sinus and mandible.

CLINICALLY RELEVANT ANATOMY The maxillary division (V2) of the trigeminal nerve is a pure sensory nerve. It exits the middle cranial fossa via the foramen rotundum and crosses the pterygopalatine fossa (Fig. 14-1). Passing through the inferior orbital fissure, it enters the orbit, emerging on the face via the infraorbital foramen. The maxillary nerve can be selectively blocked by placing a needle just above the anterior margin of the lateral pterygoid plate. The maxillary nerve provides sensory innervation for the dura of the middle cranial fossa, the temporal and lateral zygomatic region, and the mucosa of the maxillary sinus. The nerve also provides sensory innervation for the upper molars, premolars, incisors, canines, and associated oral gingiva as well as the mucous membranes of the cheek (Fig. 14-2). The nasal cavity, lower eyelid, skin of the side of the nose, and upper lip are also subserved by the maxillary nerve. The mandibular division (V3) is composed of a large sensory root and a smaller motor root. Both leave the middle cranial fossa together via the foramen ovale and join to form the mandibular nerve. Branches of the mandibular nerve provide sensory innervation to portions of the dura mater and the mucosal lining of the mastoid sinus. Sensory innervation to the skin overlying the muscles of mastication, the tragus and helix of the ear,

14

SELECTIVE MANDIBULAR NERVE BLOCK: CORONOID APPROACH

ABSTRACT

KEY WORDS

Trigeminal nerve block through the coronoid approach is used to block the maxillary and mandibular divisions of the trigeminal nerve. The maxillary division (V2) of the trigeminal nerve is a pure sensory nerve (see Fig. 14-2). It exits the middle cranial fossa via the foramen rotundum and crosses the pterygopalatine fossa where it is amenable to blockade via trigeminal nerve block via the coronoid approach. The mandibular division (V3) is composed of a large sensory root and smaller motor root. Both leave the middle cranial fossa together via the foramen ovale and join to form the mandibular nerve. The smaller motor branch provides innervation to the masseter, external pterygoid, and temporalis muscles. The technique of trigeminal nerve block via the coronoid approach can be used to perform diagnostic, prognostic, and therapeutic neural blockade of the maxillary and mandibular divisions of the trigeminal nerve. This approach allows selective blockade of the maxillary and mandibular divisions, so the technique can also be used in a prognostic manner before neurodestruction of these nerves. Procedures for neurodestruction of the maxillary and mandibular nerves by neurolytic agents, radiofrequency lesioning, or freezing may be carried out using selective maxillary and mandibular nerve block techniques.

cancer pain mandibular nerve mandibular nerve block maxillary nerve maxillary nerve block

pterygopalatine fossa trigeminal nerve trigeminal nerve block trigeminal neuralgia

51.e1

52

SECTION I

HEAD V2, Maxillary division Frontal n.

V1, Ophthalmic division Gasserian ganglion

Supratrochlear n. Supraorbital n.

Infraorbital n.

Mental n. V3, Mandibular division

Lingual n.

Figure 14-1 Anatomy of the gasserian ganglion and trigeminal nerve. Inf., Inferior; n., nerve.

Inf. alveolar n.

the posterior temporomandibular joint, the chin, and the dorsal aspect of the anterior two thirds of the tongue and associated mucosa of the oral cavity is also provided by the mandibular nerve (see Fig. 14-2). The smaller motor branch provides innervation to the masseter, external pterygoid, and temporalis muscles.

V1

V2

V3

V1, Ophthalmic nerve V2, Maxillary nerve V3, Mandibular nerve

Figure 14-2

Divisions of the trigeminal nerve.

TECHNIQUE Landmark and Fluoroscopically Guided Technique The patient is placed in the supine position with the cervical spine in the neutral position. The coronoid notch is identified by asking the patient to open and close the mouth several times and palpating the area just anterior and slightly inferior to the acoustic auditory meatus. After the notch is identified, the patient is asked to hold his or her mouth in neutral position. After the skin overlying the coronoid notch is prepared with antiseptic solution, a 22-gauge, 31 2-inch styletted needle is inserted just below the zygomatic arch directly in the middle of the coronoid notch. The needle is advanced about 11 2 to 2 inches in a plane perpendicular to the skull until the lateral pterygoid plate is encountered (Fig. 14-3). For selective blockade of the mandibular nerve, the styletted needle is withdrawn after it comes in contact with the lateral pterygoid plate and is redirected posteriorly and slightly inferiorly so that it will slip past the inferior margin of the lateral pterygoid plate (Figs. 14-4 and 14-5). A paresthesia in the distribution of the mandibular nerve is usually elicited about 1 cm deeper than the point at which the lateral pterygoid plate was encountered, and the patient should be warned of such. After careful aspiration, 3 to 5 mL of solution is injected in incremental doses. During the injection procedure, the patient must be observed carefully for signs of local anesthetic toxicity. The technique for selective mandibular nerve block via the coronoid approach may be used to place radiofrequency needles, cryoprobes, and stimulating electrodes.

14

SELECTIVE MANDIBULAR NERVE BLOCK: CORONOID APPROACH

53

Figure 14-3

Figure 14-5

Ultrasound-Guided Technique

ball-shaped mandibular condyle and the mandibular neck. Under real-time ultrasound guidance, a 22-gauge, 31 2-inch needle is inserted just below the zygomatic arch directly in the middle of the coronoid notch using an out-of-plane approach. The needle is advanced until it impinges on the lateral pterygoid plate. The tip of the needle is then withdrawn slightly out of the periosteum of the lateral pterygoid plate and redirected toward the pupil of the eye until it slips past the anterosuperior margin of the lateral pterygoid plate into the

Needle placed through the coronoid notch with tip resting against the lateral pterygoid plate.

The coronoid notch is identified as described in the previous section. After the coronoid notch is identified, a high-frequency linear ultrasound transducer is placed in a transverse position over the coronoid notch and a sonogram is taken (Fig. 14-6). The coronoid notch provides an acoustic window into the pterygopalatine fossa and allows easy identification of the maxillary nerve (Fig. 14-7). The temporomandibular joint should be identified in the posterior aspect of the sonogram by locating the

Needle tip placed beyond the inferior margin of the lateral pterygoid plate.

Lateral pterygoid plate

Maxillary nerve Auditory meatus

Mandibular nerve

Figure 14-4

For selective blockade of the mandibular nerve, the styletted needle is withdrawn after it comes in contact with the lateral pterygoid plate and is redirected posteriorly and slightly inferiorly so that it will slip past the inferior margin of the lateral pterygoid plate.

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Figure 14-6

Proper transverse location of the high-frequency linear ultrasound transducer for needle placement via the coronoid notch to block the mandibular nerve.

pterygopalatine fissure and in proximity to the maxillary nerve. A paresthesia may be elicited, and the patient should be warned of such. After careful aspiration, 4 to 5 mL of local anesthetic and 40 to 80 mg of depot-steroid are injected in incremental doses. During the injection procedure, the patient must be observed carefully for signs of local anesthetic toxicity. Because of the proximity of the sphenopalatine ganglion, the patient may also experience partial blockade of this structure. The needle is removed and pressure is placed on the injection site to avoid ecchymosis.

SIDE EFFECTS AND COMPLICATIONS Because of the highly vascular nature of the pterygopalatine fossa, significant facial hematoma may occur after trigeminal nerve block via the coronoid approach. This vascularity means that the pain specialist should use

Figure 14-8

Acute herpes zoster (shingles) involving the mandibular branch of the trigeminal nerve. (From Sapp JP, Eversole LR, Wysocki GP: Oral infections. In Contemporary Oral and Maxillofacial Pathology, 2nd ed. St Louis, Mosby, 2004, pp 207-251.)

small, incremental doses of local anesthetic to avoid local anesthetic toxicity. Postprocedure dysesthesia, including anesthesia dolorosa, may occur in a small number of patients who undergo neurodestructive procedures of the branches of the trigeminal nerve. These dysesthesias can range from mild pulling or burning sensations to severe postprocedure pain called anesthesia dolorosa. These postprocedure symptoms are thought to be due to incomplete destruction of the neural structures. Sloughing of skin in the area of anesthesia also may occur. In addition to disturbances of sensation, blockade or destruction of the branches of the trigeminal nerve may result in abnormal motor function, including weakness of the muscles of mastication and secondary facial asymmetry due to muscle weakness or loss of proprioception. The patient should be warned that all of these complications may occur.

Clinical Pearls Zygomatic arch

Masseter

Temporalis Mandibular arch Sphenopalatine ganglion

Figure 14-7 Ultrasound image through the acoustic window provided by the coronoid notch demonstrating the mandibular nerve. Note the proximity of the sphenopalatine ganglion.

Trigeminal nerve block via the coronoid approach with local anesthetic and steroid represents an excellent stopgap measure for patients suffering from the uncontrolled pain of trigeminal neuralgia, acute herpes zoster, and cancer pain while waiting for pharmacologic treatments to take effect (Fig. 14-8). The major side effects of this block are related to the vascular nature of the pterygopalatine fossa, and care must be taken to avoid local anesthetic toxicity. Despite this vascularity, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of facial hematoma, should the clinical situation indicate a favorable risk-to-benefit ratio. Because repeated needle punctures with daily or everyother-day blocks may result in small punctate facial scars, patients should be warned of this possibility. Infection, although rare, remains an ever-present possibility, especially in the immunocompromised patient. Early detection of infection is crucial to avoid potentially life-threatening sequelae.

C H A P T E R

15

Supraorbital Nerve Block CPT-2015 Code Unilateral Bilateral Neurolytic

64400 64400-50 64600

CLINICALLY RELEVANT ANATOMY

Relative Value Units Unilateral Bilateral Neurolytic

technique is also useful in providing surgical anesthesia in the distribution of the supraorbital nerve for lesion removal and laceration repair.

5 10 20

INDICATIONS Supraorbital nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the supraorbital nerve, including supraorbital neuralgia and pain secondary to acute herpes zoster (Fig. 15-1). This

The supraorbital nerve arises from fibers of the frontal nerve, which is the largest branch of the ophthalmic nerve. The frontal nerve enters the orbit via the superior orbital fissure and passes anteriorly beneath the periosteum of the roof of the orbit (Fig. 15-2). The frontal nerve gives off a larger lateral branch, the supraorbital nerve, and a smaller medial branch, the supratrochlear nerve. Both exit the orbit anteriorly. The supraorbital nerve sends fibers all the way to the vertex of the scalp and provides sensory innervation to the forehead, upper eyelid, and anterior scalp (Fig. 15-3).

V1 Supratrochlear Infratrochlear Supraorbital External nasal Lacrimal

V1

V2 Zygomaticotemporal Zygomaticofacial Infraorbital V2 V3 Auriculotemporal Buccal Mental V3

V1, Ophthalmic nerve

Figure 15-1

Ophthalmic herpes zoster vesicles and crusting of the top and side of the nose in herpes zoster (positive Hutchinson’s sign) implies involvement of the nasociliary branch of the trigeminal nerve and eye involvement. (From Buttaravoli P: Herpes zoster [shingles]. In Minor Emergencies, 2nd ed. Philadelphia, Mosby, 2007, pp 709-714.)

V2, Maxillary nerve V3, Mandibular nerve

Figure 15-2

Peripheral branches of the trigeminal nerve.

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SUPRAORBITAL NERVE BLOCK

ABSTRACT

KEY WORDS

The supraorbital nerve arises from fibers of the frontal nerve, which is the largest branch of the ophthalmic nerve. The frontal nerve enters the orbit via the superior orbital fissure and passes anteriorly beneath the periosteum of the roof of the orbit. The frontal nerve gives off a larger lateral branch, the supraorbital nerve, and a smaller medial branch, the supratrochlear nerve. Both exit the orbit anteriorly. The supraorbital nerve sends fibers all the way to the vertex of the scalp and provides sensory innervation to the forehead, upper eyelid, and anterior scalp. Supraorbital nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the supraorbital nerve, including supraorbital neuralgia and pain secondary to acute herpes zoster. Supraorbital nerve block can be used in a diagnostic, prognostic, and therapeutic manner.

acute herpes zoster supraorbital nerve supraorbital nerve block supratrochlear nerve

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Figure 15-5 Technique of supraorbital nerve block. (From Massry GG: Ptosis repair for the cosmetic surgeon. Facial Plast Surg Clin North Am 13[4]:533-539, 2005.)

Sensory distribution of supraorbital nerve

Figure 15-3

Sensory division of the supraorbital nerve.

TECHNIQUE Landmark and Fluoroscopically Guided Technique The patient is placed in the supine position. A total of 3 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for supraorbital neuralgia, acute herpes zoster, postherpetic neuralgia, or other painful conditions involving the supraorbital nerve, a

total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The supraorbital foramen on the affected side is then identified by palpation. The skin overlying the foramen is prepared with antiseptic solution, with care being taken to avoid spillage into the eye. A 25-gauge, 1 1 2-inch needle is inserted at the level of the supraorbital foramen and is advanced medially about 15 degrees off the perpendicular to avoid entering the foramen. The needle is advanced until it approaches the periosteum of the underlying bone (Figs. 15-4 and 15-5). A paresthesia may be elicited, and the patient should be warned of such. The needle should not enter the supraorbital foramen, and should this occur,

Supraorbital n.

Supraorbital notch

Figure 15-4 For supraorbital nerve block, a 25-gauge, 1 1 2-inch needle is inserted at the level of the supraorbital foramen and is advanced medially about 15 degrees off the perpendicular to avoid entering the foramen. n., Nerve.

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Supraorbital foramen Supraorbital foramen

Supraorbital artery

Supraorbital nerve

Supraorbital ridge

Figure 15-8 Color Doppler imaging may also be used to identify the supraorbital artery, which exits the supraorbital foramen along with the supraorbital nerve.

Ultrasound-Guided Technique Figure 15-6 Fluoroscopic image demonstrating the needle tip in proximity to the supraorbital nerve.

the needle should be withdrawn and redirected slightly more medially. Fluoroscopy may be used if there is difficulty identifying the supraorbital foramen (Fig. 15-6). Because of the loose alveolar tissue of the eyelid, a gauze sponge should be used to apply gentle pressure on the upper eyelid and supraorbital tissues before injection of solution to prevent the injectate from dissecting inferiorly into these tissues. This pressure should be maintained after the procedure to avoid periorbital hematoma and ecchymosis. After gentle aspiration, 3 mL of solution is injected in a fanlike distribution. If blockade of the supratrochlear nerve is also desired, the needle is then redirected medially, and after careful aspiration, an additional 3 mL of solution is injected in a fanlike manner.

The patient is placed in the supine position. A total of 3 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for supraorbital neuralgia, acute herpes zoster, postherpetic neuralgia, or other painful conditions involving the supraorbital nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The supraorbital foramen on the affected side is then identified by palpation. The skin overlying the foramen is prepared with antiseptic solution, with care being taken to avoid spillage into the eye. A high-frequency linear ultrasound transducer is placed in the transverse position over the previously identified foramen and a sonogram is taken. The supraorbital foramen will be easily identified as a discontinuity of the hyperechoic supraorbital ridge (Fig. 15-7). Color Doppler imaging may also be used to identify the supraorbital artery, which exits the supraorbital foramen along with the supraorbital nerve (Fig. 15-8).

Supraorbital foramen

Figure 15-7

On an ultrasound image, the supraorbital foramen is easily identified as a discontinuity of the hyperechoic supraorbital ridge.

Supraorbital ridge

Once the supraorbital foramen containing the supraorbital nerve and artery has been identified, a 25-gauge, 1 1 2-inch needle is inserted at the inferior margin of the ultrasound transducer and advanced medially about 15 degrees off the perpendicular toward the supraorbital foramen using an out-of-plane approach. The needle is advanced under continuous ultrasound guidance until it is in proximity to the supraorbital nerve as it exits the supraorbital foramen. A paresthesia may be elicited, and the patient should be warned of such. The needle should not enter the supraorbital foramen, and should this occur, the needle should be withdrawn and redirected slightly more medially. Because of the loose alveolar tissue of the eyelid, a gauze sponge should be used to apply gentle pressure on the upper eyelid and supraorbital tissues before injection of solution to prevent the injectate from dissecting inferiorly into these tissues (Fig. 15-9). This pressure should

be maintained after the procedure to avoid periorbital hematoma and ecchymosis. After gentle aspiration, 3 mL of solution is injected in a fanlike distribution. If blockade of the supratrochlear nerve is also desired, the needle is then redirected medially, and after careful aspiration, an additional 3 mL of solution is injected in a fanlike manner.

SIDE EFFECTS AND COMPLICATIONS The forehead and scalp are highly vascular, and the pain specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely, especially if bilateral nerve blocks are being performed. This vascularity gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable risk-to-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20-minute periods after the block also decreases the amount of postprocedure pain and bleeding the patient may experience.

Clinical Pearls

Figure 15-9

Proper position of the ultrasound transducer for supraorbital nerve block. Because of the loose alveolar tissue of the eyelid, a gauze sponge should be used to apply gentle pressure on the upper eyelid and supraorbital tissues before injection of solution to prevent the injectate from dissecting inferiorly into these tissues.

Supraorbital nerve block is especially useful in the palliation of pain secondary to acute herpes zoster involving the ophthalmic division and its branches. In this setting, the pain management specialist also has to block the supratrochlear nerve. The addition of tepid aluminum acetate soaks helps dry weeping lesions and makes the patient more comfortable. Care should be taken to avoid spillage of the aluminum acetate solution into the eye.

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C H A P T E R

16

Supratrochlear Nerve Block CPT-2015 Code Unilateral Bilateral Neurolytic

Relative Value Units 64400 64400-50 64600

Unilateral Bilateral Neurolytic

5 10 20

16

SUPRATROCHLEAR NERVE BLOCK

ABSTRACT

KEY WORDS

The supratrochlear nerve arises from fibers of the frontal nerve, which is the largest branch of the ophthalmic nerve. The frontal nerve enters the orbit via the superior orbital fissure and passes anteriorly beneath the periosteum of the roof of the orbit. The frontal nerve gives off a larger lateral branch, the supraorbital nerve, and a smaller medial branch, the supratrochlear nerve. Both exit the orbit anteriorly. The supraorbital nerve sends fibers all the way to the vertex of the scalp and provides sensory innervation to the forehead, upper eyelid, and anterior scalp. Supraorbital nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the supraorbital nerve, including supraorbital neuralgia and pain secondary to acute herpes zoster. Supraorbital nerve block can be used in a diagnostic, prognostic, and therapeutic manner.

acute herpes zoster supraorbital nerve supraorbital nerve block supratrochlear nerve

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16

SUPRATROCHLEAR NERVE BLOCK

59

INDICATIONS Supratrochlear nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the supratrochlear nerve, including supratrochlear neuralgia and pain secondary to herpes zoster. This technique is also useful in providing surgical anesthesia in the distribution of the supratrochlear nerve for lesion removal and laceration repair.

CLINICALLY RELEVANT ANATOMY The supratrochlear nerve arises from fibers of the frontal nerve, which is the largest branch of the ophthalmic nerve. The frontal nerve enters the orbit via the superior orbital fissure and passes anteriorly beneath the periosteum of the roof of the orbit. The frontal nerve gives off a larger lateral branch, the supraorbital nerve, and a smaller medial branch, the supratrochlear nerve (Fig. 16-1). Both exit the orbit anteriorly. The supratrochlear nerve sends fibers to provide sensory innervation to the inferomedial section of the forehead, the bridge of the nose, and the medial portion of the upper eyelid (Fig. 16-2).

TECHNIQUE

Sensory distribution of supratrochlear nerve

Landmark and Fluoroscopically Guided Technique The patient is placed in the supine position. A total of 3 mL of local anesthetic is drawn up in a 10-mL sterile V1 Supratrochlear Infratrochlear Supraorbital External nasal Lacrimal

V1

V2 Zygomaticotemporal Zygomaticofacial Infraorbital V2 V3 Auriculotemporal Buccal Mental V3

V1, Ophthalmic nerve V2, Maxillary nerve V3, Mandibular nerve

Figure 16-1

Peripheral branches of the trigeminal nerve.

Figure 16-2

Sensory distribution of the supratrochlear nerve.

syringe. When the treatment is for supratrochlear neuralgia, acute herpes zoster, postherpetic neuralgia, or other painful conditions involving the supratrochlear nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The supraorbital ridge on the affected side is then identified by palpation. The skin at the point where the bridge of the nose abuts the supraorbital ridge is prepared with antiseptic solution, with care being taken to avoid spillage into the eye. The patient’s head should be stabilized to avoid inadvertent trauma to the eye. A 25-gauge, 1 1 2-inch needle is inserted just lateral to the junction of the bridge of the nose and the supraorbital ridge and is advanced medially into the subcutaneous tissue (Figs. 16-3 and 16-4). A paresthesia may be elicited, and the patient should be warned of such. Because of the loose alveolar tissue of the eyelid, a gauze sponge should be used to apply gentle pressure on the upper eyelid and supratrochlear tissues before injection of solution to prevent the injectate from dissecting inferiorly into these tissues. This pressure should be maintained after the procedure to avoid periorbital hematoma and ecchymosis. After gentle aspiration, 3 mL of solution is injected in a fanlike distribution.

SIDE EFFECTS AND COMPLICATIONS The forehead and scalp are highly vascular, and the pain specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely, especially if bilateral nerve blocks are being performed. This vascularity gives rise to an increased incidence of postblock

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Supratrochlear n.

Figure 16-3 Technique for supratrochlear nerve block. n., Nerve.

Figure 16-4 The patient’s head should be stabilized to avoid inadvertent trauma to the eye. ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable risk-to-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20-minute periods after the block also decreases the amount of postprocedure pain and bleeding the patient may experience.

Figure 16-5 Subcutaneous lead placement for supratrochlear and supraorbital nerve stimulation in a patient with post–eye enucleation pain syndrome. (From de Leon-Casasola OA: Spinal cord and peripheral nerve stimulation techniques for neuropathic pain. J Pain Symptom Manage 38[2 suppl]:S28-S38, 2009.)

Clinical Pearls Supratrochlear nerve block is especially useful in the palliation of pain secondary to acute herpes zoster involving the ophthalmic division and its branches. In this setting, the pain management specialist also has to block the supraorbital nerve. The addition of tepid aluminum acetate soaks helps dry weeping lesions and makes the patient more comfortable. Care

should be taken to avoid spillage of the aluminum acetate solution into the eye. Recent clinical experience suggests that stimulation of the supratrochlear nerve may be useful in the treatment of intractable pain syndromes subserved by the supratrochlear nerve (Fig. 16-5).

C H A P T E R

17

Infraorbital Nerve Block: Extraoral Approach CPT-2015 Code Unilateral Bilateral Neurolytic

64400 64400-50 64600

Relative Value Units Unilateral Bilateral Neurolytic

5 10 20

INDICATIONS Infraorbital nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the infraorbital nerve, including infraorbital neuralgia and pain secondary to herpes zoster. This technique is also useful in providing surgical anesthesia in the distribution of the infraorbital nerve for lesion removal and laceration repair (Fig. E17-1).

inserted at the level of the infraorbital notch and is advanced medially about 15 degrees off the perpendicular to avoid entering the foramen. The needle is advanced until it approaches the periosteum of the underlying bone (Figs. 17-3 and 17-4). A paresthesia may be elicited, and the patient should be warned of such. The needle should not enter the infraorbital foramen, and should this occur, the needle should be withdrawn and redirected slightly more medially. Because of the loose alveolar tissue of the eyelid, a gauze sponge should be used to apply gentle pressure on the lower eyelid and infraorbital tissues before injection of solution to prevent the injectate from dissecting upward into these tissues. This pressure should be maintained after the procedure to avoid periorbital hematoma and ecchymosis. After gentle aspiration, 3 mL of solution is injected in a fanlike distribution.

V1 Supratrochlear Infratrochlear Supraorbital External nasal Lacrimal

CLINICALLY RELEVANT ANATOMY The infraorbital nerve arises from fibers of the maxillary nerve. The infraorbital nerve enters the orbit via the inferior orbital fissure and passes along the floor of the orbit in the infraorbital groove (Fig. 17-1). The nerve exits the orbit via the infraorbital foramen and provides cutaneous branches that innervate the lower eyelid, lateral naris, and upper lip (Fig. 17-2). The superior alveolar branch of the infraorbital nerves provides sensory innervation to the upper incisor, canine, and associated gingiva.

V1

V2 Zygomaticotemporal Zygomaticofacial Infraorbital V2 V3 Auriculotemporal Buccal Mental

TECHNIQUE Landmark and Fluoroscopically Guided Technique The patient is placed in the supine position. A total of 3 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for infraorbital neuralgia, facial trauma, or other painful conditions involving the infraorbital nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The infraorbital notch on the affected side is then identified by palpation. The skin overlying the notch is prepared with antiseptic solution, with care taken to avoid spillage into the eye. A 25-gauge, 11 2-inch needle is

V3

V1, Ophthalmic nerve V2, Maxillary nerve V3, Mandibular nerve

Figure 17-1

Peripheral branches of the trigeminal nerve.

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INFRAORBITAL NERVE BLOCK: EXTRAORAL APPROACH

ABSTRACT

KEY WORDS

The infraorbital nerve arises from fibers of the maxillary nerve. The infraorbital nerve enters the orbit via the inferior orbital fissure and passes along the floor of the orbit in the infraorbital groove. The nerve exits the orbit via the infraorbital foramen and provides cutaneous branches that innervate the lower eyelid, lateral naris, and upper lip. The superior alveolar branch of the infraorbital nerves provides sensory innervation to the upper incisor, canine, and associated gingiva. Infraorbital nerve block can be used in a diagnostic, prognostic, and therapeutic manner.

acute herpes zoster infraorbital nerve infraorbital nerve block superior alveolar nerve

Figure E17-1

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trigeminal nerve trigeminal nerve maxillary division

Basal cell carcinoma involving the nares. (From Crawford KM, Kobayashi T: Nevoid basal cell carcinoma syndrome or multiple hereditary infundibulocystic basal cell carcinoma syndrome? J Am Acad Dermatol 51[6]:989-995, 2004.)

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Figure 17-4 Fluoroscopic image demonstrating the needle tip in proximity to the infraorbital nerve. Sensory distribution of infraorbital nerve

Figure 17-2

Sensory distribution of the infraorbital nerve.

Ultrasound-Guided Technique The patient is placed in the supine position. A total of 3 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for infraorbital neuralgia, acute herpes zoster, postherpetic neuralgia, or other painful conditions involving the infraorbital nerve, a

total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The infraorbital foramen on the affected side is then identified by palpation. The skin overlying the foramen is prepared with antiseptic solution, with care being taken to avoid spillage into the eye. A high-frequency linear ultrasound transducer is placed in the transverse position

Infraorbital n. Infraorbital foramen

Figure 17-3

Technique of infraorbital nerve block using the extraoral approach. n., Nerve.

17

INFRAORBITAL NERVE BLOCK: EXTRAORAL APPROACH

63

not enter the infraorbital foramen, and should this occur, the needle should be withdrawn and redirected slightly more medially. Because of the loose alveolar tissue of the eyelid, a gauze sponge should be used to apply gentle pressure on the upper eyelid and infraorbital tissues before injection of solution to prevent the injectate from dissecting inferiorly into these tissues. This pressure should be maintained after the procedure to avoid periorbital hematoma and ecchymosis. After gentle aspiration, 3 mL of solution is injected in a fanlike distribution.

SIDE EFFECTS AND COMPLICATIONS Figure 17-5

Proper transverse placement of the high-frequency linear ultrasound transducer over the infraorbital ridge.

over the previously identified notch and a sonogram is taken (Fig. 17-5). The infraorbital foramen will be easily identified as a discontinuity of the hyperechoic infraorbital ridge. Color Doppler imaging may also be used to identify the infraorbital artery, which exits the infraorbital foramen along with the infraorbital nerve (Fig. 17-6). Once the infraorbital foramen containing the infraorbital nerve and artery have been identified, a 25-gauge, 11 2-inch needle is inserted at the inferior margin of the ultrasound transducer and advanced medially about 15 degrees off the perpendicular toward the infraorbital foramen using an out-of-plane approach. The needle is advanced under continuous ultrasound guidance until it is in proximity to the infraorbital nerve as it exits the infraorbital foramen. A paresthesia may be elicited, and the patient should be warned of such. The needle should

The face is highly vascular, and the pain specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely, especially if bilateral nerve blocks are being performed. This vascularity gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can safely be performed in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable risk-to-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20-minute periods after the block also decreases the amount of postprocedure pain and bleeding the patient may experience. The pain management specialist should avoid inserting the needle directly into the infraorbital foramen because the nerve may be damaged as solution is injected into the bony canal, which results in a compression neuropathy.

Infraorbital nerve

Infraorbital foramen

Figure 17-6

Infraorbital artery

Ultrasound image demonstrating the infraorbital foramen, nerve, and artery.

Clinical Pearls Infraorbital nerve block is useful in the palliation of pain secondary to facial trauma and neuropathic pain involving the infraorbital nerve. In the pediatric population and in patients requiring repair of facial lacerations, the intraoral approach to blockade of the infraorbital nerve should be considered. Because repeated needle punctures with daily or every-other-day blocks may result in small punctate facial scars, patients should be warned of this possibility. Infection, although rare, remains an ever-present possibility, especially in the immunocompromised patient. Early detection of infection is crucial to avoid potentially life-threatening sequelae. Recent clinical experience suggests that stimulation of the supratrochlear nerve may be useful in the treatment of intractable pain syndromes in areas subserved by the supratrochlear nerve (Fig. 17-7).

Figure 17-7 Subcutaneous lead placement for infraorbital nerve stimulation in a patient with pain after excision of a basal cell carcinoma of the face. (From de Leon-Casasola OA: Spinal cord and peripheral nerve stimulation techniques for neuropathic pain. J Pain Symptom Manage 38[2 suppl]:S28-S38, 2009.)

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18

Infraorbital Nerve Block: Intraoral Approach INDICATIONS

CPT-2015 Code Unilateral Bilateral Neurolytic

64400 64400-5 64600

Relative Value Units Unilateral Bilateral Neurolytic

5 10 20

Infraorbital nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the infraorbital nerve, including infraorbital neuralgia and pain secondary to herpes zoster. The intraoral approach to infraorbital nerve block is especially useful in providing surgical anesthesia in the distribution of the infraorbital nerve for lesion removal and laceration repair when a cosmetic result is desired, because this approach avoids distortion of the facial anatomy from local anesthetic infiltration at the surgical site. This approach also provides an alternative needle path in patients in whom cutaneous

18

INFRAORBITAL NERVE BLOCK: INTRAORAL APPROACH

ABSTRACT

KEY WORDS

The infraorbital nerve arises from fibers of the maxillary nerve. The infraorbital nerve enters the orbit via the inferior orbital fissure and passes along the floor of the orbit in the infraorbital groove. The nerve exits the orbit via the infraorbital foramen and provides cutaneous branches that innervate the lower eyelid, lateral naris, and upper lip. The superior alveolar branch of the infraorbital nerves provides sensory innervation to the upper incisor, canine, and associated gingiva. Infraorbital nerve block can be used in a diagnostic, prognostic, and therapeutic manner.

acute herpes zoster infraorbital nerve infraorbital nerve block superior alveolar nerve

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INFRAORBITAL NERVE BLOCK: INTRAORAL APPROACH

65

V1 Supratrochlear Infratrochlear Supraorbital External nasal Lacrimal

V1

V2 Zygomaticotemporal Zygomaticofacial Infraorbital V2 V3 Auriculotemporal Buccal Mental V3

Figure 18-1 The intraoral approach to infraorbital nerve block provides an alternative needle path in patients in whom cutaneous lesions preclude the use of the extraoral approach to infraorbital nerve block. (From Pelissier P, Bodin F, Kadoch V, et al: Six cas de carcinomes annexiels de la face avec reconstruction. Ann Chir Plast Esthet 58[2]: 103-108, 2013.)

V1, Ophthalmic nerve V2, Maxillary nerve V3, Mandibular nerve

Figure 18-2

Peripheral branches of the trigeminal nerve.

lesions preclude the use of the extraoral approach to infraorbital nerve block (Fig. 18-1). The intraoral approach is also useful in the pediatric population.

CLINICALLY RELEVANT ANATOMY The infraorbital nerve arises from fibers of the maxillary nerve. The infraorbital nerve enters the orbit via the inferior orbital fissure and passes along the floor of the orbit in the infraorbital groove (Fig. 18-2). The nerve exits the orbit via the infraorbital foramen and provides cutaneous branches that innervate the lower eyelid, lateral naris, and upper lip (Fig. 18-3). The superior alveolar branch of the infraorbital nerve provides sensory innervation to the upper incisor, canine, and associated gingiva.

TECHNIQUE Landmark and Fluoroscopically Guided Technique The patient is placed in the supine position. A total of 3 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for infraorbital neuralgia, facial trauma, or other painful conditions involving the infraorbital nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The infraorbital foramen on the affected side is then identified by palpation. The upper lip is pulled backward, and a cotton ball soaked in 10% cocaine solution or 2% viscous lidocaine is placed in the alveolar sulcus, just

Sensory distribution of infraorbital nerve

Figure 18-3

Sensory distribution of the infraorbital nerve.

66

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Ultrasound-Guided Technique

Figure 18-4

To provide topical anesthesia of the mucosa overlying the superior alveolar sulcus, the upper lip is pulled backward, and a cotton ball soaked in 10% cocaine solution or 2% viscous lidocaine is placed in the superior alveolar sulcus, just inferior to the infraorbital foramen.

inferior to the infraorbital foramen (Fig. 18-4). After adequate topical anesthesia of the mucosa is obtained, a 25-gauge, 11 2-inch needle is advanced through the anesthetized mucosa toward the infraorbital foramen (Fig. 18-5). A paresthesia may be elicited, and the patient should be warned of such. Because of the loose alveolar tissue of the eyelid, a gauze sponge should be used to apply gentle pressure on the lower eyelid and infraorbital tissues before injection of solution to prevent the injectate from dissecting upward into these tissues. This pressure should be maintained after the procedure to avoid periorbital hematoma and ecchymosis. After gentle aspiration, 3 mL of solution is injected in a fanlike distribution.

The patient is placed in the supine position. A total of 3 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for infraorbital neuralgia, facial trauma, or other painful conditions involving the infraorbital nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The infraorbital foramen on the affected side is then identified by palpation. The upper lip is pulled backward, and a cotton ball soaked in 10% cocaine solution or 2% viscous lidocaine is placed in the alveolar sulcus, just inferior to the infraorbital foramen (see Fig. 18-4). A high-frequency linear ultrasound transducer is placed in the transverse position over the previously identified notch and a sonogram is taken (Fig. 18-6). The infraorbital foramen will be easily identified as a discontinuity of the hyperechoic infraorbital ridge. Color Doppler imaging may also be used to identify the infraorbital artery, which exits the infraorbital foramen along with the infraorbital nerve (Fig. 18-7). After adequate topical anesthesia of the mucosa is obtained, a 25-gauge, 11 2-inch needle is advanced through the anesthetized mucosa toward the infraorbital foramen (see Fig. 18-5). A paresthesia may be elicited, and the patient should be warned of such. Because of the loose alveolar tissue of the eyelid, a gauze sponge should be used to apply gentle pressure on the lower eyelid and infraorbital tissues before injection of solution to prevent the injectate from dissecting upward into these tissues. This pressure should be maintained after the procedure to avoid periorbital hematoma and ecchymosis. After gentle aspiration, 3 mL of solution is injected in a fanlike distribution.

Infraorbital n.

Infraorbital foramen

Alveolar sulcus

Figure 18-5

Proper needle trajectory through the previously anesthetized mucosa to perform infraorbital nerve block via the intraoral approach. n., Nerve.

18

INFRAORBITAL NERVE BLOCK: INTRAORAL APPROACH

67

SIDE EFFECTS AND COMPLICATIONS

Figure 18-6 Proper transverse placement of the high-frequency linear ultrasound transducer for the intraoral approach to infraorbital nerve block.

The face is highly vascular, and the pain specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely, especially if bilateral nerve blocks are being performed. This vascularity gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable risk-to-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20-minute periods after the block also decreases the amount of postprocedure pain and bleeding the patient may experience.

Infraorbital nerve

Infraorbital foramen

Infraorbital artery

Figure 18-7

Ultrasound image demonstrating the infraorbital foramen, nerve, and artery.

Clinical Pearls Infraorbital nerve block is useful in the palliation of pain secondary to facial trauma and neuropathic pain involving the infraorbital nerve. In the pediatric population and in patients requiring repair of facial lacerations, the intraoral approach to blockade of the infraorbital nerve should be considered.

When the intraoral approach is used with children, the child’s mother or father can actually place the anesthetic-soaked cotton ball in the alveolar sulcus under the pain management specialist’s direction.

C H A P T E R

19

Mental Nerve Block: Extraoral Approach CPT-2015 Code Unilateral Bilateral Neurolytic

64400 64400-50 64600

Relative Value Units Unilateral Bilateral Neurolytic

5 10 20

INDICATIONS Mental nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the mental nerve, including mental neuralgia, facial trauma, and pain secondary to herpes zoster. This technique is also useful in providing surgical anesthesia in the distribution of the mental nerve for lesion removal and laceration repair.

CLINICALLY RELEVANT ANATOMY The mental nerve arises from fibers of the mandibular nerve. The mental nerve exits the mandible via the mental foramen at the level of the second premolar, where it makes a sharp turn superiorly (Fig. 19-1). The nerve provides cutaneous branches that innervate the lower lip, chin, and corresponding oral mucosa (Fig. 19-2).

(Fig. 19-3). A paresthesia may be elicited, and the patient should be warned of such. The needle should not enter the mental foramen, and should this occur, the needle should be withdrawn and redirected slightly more medially. After gentle aspiration, 3 mL of solution is injected in a fanlike distribution. Fluoroscopy can be used to aid in needle placement in patients in whom the anatomic landmarks are difficult to identify (Fig. 19-4). The face is highly vascular, and the pain specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely, especially if bilateral nerve blocks are being performed. This vascularity gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if V1 Supratrochlear Infratrochlear Supraorbital External nasal Lacrimal

V1

V2 Zygomaticotemporal Zygomaticofacial Infraorbital V2 V3

TECHNIQUE

Auriculotemporal Buccal Mental

Landmark and Fluoroscopically Guided Technique The patient is placed in the supine position. A total of 3 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for mental neuralgia, facial trauma, or other painful conditions involving the mental nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The mental foramen on the affected side is then identified by palpation. The skin overlying the foramen is prepared with antiseptic solution. A 25-gauge, 11 2 -inch needle is inserted at the level of the mental foramen and is advanced medially about 15 degrees off the perpendicular to avoid entering the foramen. The needle is advanced until it approaches the periosteum of the underlying bone 68

V3

V1, Ophthalmic nerve V2, Maxillary nerve V3, Mandibular nerve

Figure 19-1

Peripheral branches of the trigeminal nerve.

19

MENTAL NERVE BLOCK: EXTRAORAL APPROACH

ABSTRACT

KEY WORDS

The mental nerve arises from fibers of the mandibular nerve. The mental nerve exits the mandible via the mental foramen at the level of the second premolar, where it makes a sharp turn superiorly. The nerve provides cutaneous branches that innervate the lower lip, chin, and corresponding oral mucosa. Mental nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the mental nerve, including mental neuralgia, facial trauma, and pain secondary to herpes zoster. This technique is also useful in providing surgical anesthesia in the distribution of the mental nerve for lesion removal and laceration repair. Mental nerve block can be used in a diagnostic, prognostic, and therapeutic manner.

acute herpes zoster mental nerve mental neuralgia mental nerve block

68.e1

trigeminal nerve trigeminal nerve mandibular division

19

MENTAL NERVE BLOCK: EXTRAORAL APPROACH

69

Figure 19-4 Fluoroscopic image demonstrating the needle tip in proximity to the mental nerve. Sensory distribution of mental nerve

Figure 19-2

Sensory distribution of the mental nerve.

the clinical situation indicates a favorable risk-to-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20-minute periods after the block also decreases the amount of postprocedure pain and bleeding the patient may experience.

Mental foramen

Figure 19-3

The pain management specialist should avoid inserting the needle directly into the mental foramen because the nerve may be damaged as solution is injected into the bony canal, which results in a compression neuropathy.

Ultrasound-Guided Technique The patient is placed in the supine position. A total of 3 mL of local anesthetic is drawn up in a 10-mL sterile

Mental nerve

Proper needle trajectory for mental nerve block via the extraoral approach.

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Mental foramen

Mandible

Mental nerve

Figure 19-5

Transverse ultrasound image demonstrating the mental foramen, which appears as a discontinuity of the mandible.

syringe. When the treatment is for mental neuralgia, facial trauma, or other painful conditions involving the mental nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The mental foramen on the affected side is then identified by palpation. The skin overlying the foramen is prepared with antiseptic solution. A high-frequency linear ultrasound transducer is placed in the transverse position over the previously identified foramen and a sonogram is taken (Fig. 19-5). The ultrasound transducer is moved from a caudad to cephalad trajectory until the mental foramen is identified as a discontinuity of the mandible. Color Doppler imaging may also be used to identify the mental artery, which exits the mental foramen along with the mental nerve (Fig. 19-6).

Once the mental foramen containing the mental nerve and artery have been identified, a 25-gauge, 11 2-inch needle is inserted at the inferior margin of the ultrasound transducer and advanced medially about 15 degrees off the perpendicular toward the mental foramen using an out-ofplane approach. The needle is advanced under continuous ultrasound guidance until it is in proximity to the mental nerve as it exits the mental foramen. A paresthesia may be elicited, and the patient should be warned of such. The needle should not enter the mental foramen, and should this occur, the needle should be withdrawn and redirected slightly more medially. After gentle aspiration, 3 mL of solution is injected in a fanlike distribution. The pain management specialist should avoid inserting the needle directly into the mental foramen because the nerve may be damaged as solution is injected into the bony canal, which results in a compression neuropathy.

Mental artery

Figure 19-6

Color Doppler may aid in identification of the mental artery as it exits the mental foramen.

Clinical Pearls

Figure 19-7

The mental nerve is especially susceptible to trauma due to the acute angle at which it exits the mental foramen. This threedimensional computerized tomographic image shows a mandibular fracture involving the mental foramen. (From Benech A, Nicolotti M, Brucoli M, et al: Intraoral extra-mucosal fixation of fractures in the atrophic edentulous mandible. Int J Oral Maxillofac Surg 42[4]:460463, 2013.)

Mental nerve block is useful in the palliation of pain secondary to facial trauma and neuropathic pain involving the mental nerve. In the pediatric population and in patients requiring repair of facial lacerations, the intraoral approach to blockade of the mental nerve should be considered. Because repeated needle punctures with daily or everyother-day blocks may result in small punctate facial scars, patients should be warned of this possibility. Infection, although rare, remains an ever-present possibility, especially in the immunocompromised patient. Early detection of infection is crucial to avoid potentially life-threatening sequelae. The pain specialist should carefully examine the patient before performing mental nerve block to identify preexisting neural compromise because the mental nerve is especially vulnerable to blunt trauma and mandibular fractures owing to the acute angle at which it exits the mental foramen (Fig. 19-7). This preblock assessment helps identify subtle neurologic changes that might subsequently be erroneously attributed to the block.

20

MENTAL NERVE BLOCK: INTRAORAL APPROACH

C H A P T E R

71

20

Mental Nerve Block: Intraoral Approach Cpt-2015 Code Unilateral Bilateral Neurolytic

64400 64400-50 64600

CLINICALLY RELEVANT ANATOMY

Relative Value Units Unilateral Bilateral Neurolytic

distribution of the mental nerve for lesion removal and laceration repair when a cosmetic result is desired, because this approach avoids distortion of the facial anatomy from local anesthetic infiltration at the surgical site (Fig. 20-1).

5 10 20

INDICATIONS Mental nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the mental nerve, including mental neuralgia, facial trauma, and pain secondary to herpes zoster. The intraoral approach to mental nerve block is especially useful in providing surgical anesthesia in the

The mental nerve arises from fibers of the mandibular nerve. The mental nerve exits the mandible via the mental foramen at the level of the second premolar, where it makes a sharp turn superiorly (Fig. 20-2). The nerve provides cutaneous branches that innervate the lower lip, chin, and corresponding oral mucosa (Fig. 20-3).

TECHNIQUE Landmark and Fluoroscopically Guided Technique The patient is placed in the supine position. A total of 3 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for mental neuralgia,

20

MENTAL NERVE BLOCK: INTRAORAL APPROACH

ABSTRACT

KEY WORDS

The mental nerve arises from fibers of the mandibular nerve. The mental nerve exits the mandible via the mental foramen at the level of the second premolar, where it makes a sharp turn superiorly. The nerve provides cutaneous branches that innervate the lower lip, chin, and corresponding oral mucosa. Mental nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the mental nerve, including mental neuralgia, facial trauma, and pain secondary to herpes zoster. This technique is also useful in providing surgical anesthesia in the distribution of the mental nerve for lesion removal and laceration repair. Mental nerve block can be used in a diagnostic, prognostic, and therapeutic manner.

acute herpes zoster mental nerve mental neuralgia mental nerve block

71.e1

trigeminal nerve trigeminal nerve mandibular division

A

B

C

D

Figure 20-1 The intraoral approach to mental nerve block is especially useful in providing surgical anesthesia in the distribution of the mental nerve for lesion removal and laceration repair when a cosmetic result is desired, because this approach avoids distortion of the facial anatomy from local anesthetic infiltration at the surgical site and the need to place the needle through a lesion, such as the advanced basal cell carcinoma shown here. (From Bhatnagar A: Nonmelanoma skin cancer treated with electronic brachytherapy: results at 1 year. Brachytherapy 12[2]:134-140, 2013.) V1 Supratrochlear Infratrochlear Supraorbital External nasal Lacrimal

V1

V2 Zygomaticotemporal Zygomaticofacial Infraorbital V2 V3 Auriculotemporal Buccal Mental V3

Sensory distribution of mental nerve V1, Ophthalmic nerve V2, Maxillary nerve V3, Mandibular nerve

Figure 20-2 The mental nerve exits the mandible via the mental foramen at the level of the second premolar, where it makes a sharp turn superiorly.

Figure 20-3

Sensory distribution of the mental nerve.

20

MENTAL NERVE BLOCK: INTRAORAL APPROACH

73

facial trauma, or other painful conditions involving the mental nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The mental notch on the affected side is then identified by palpation. The lower lip is pulled downward, and a cotton ball soaked in 10% cocaine solution or 2% viscous lidocaine is placed in the alveolar sulcus, just above the mental foramen (Fig. 20-4). After adequate topical anesthesia of the mucosa is obtained, a 25-gauge, 11 2-inch needle is advanced through the anesthetized mucosa toward the mental foramen (Fig. 20-5). A paresthesia may be elicited, and the patient should be warned of such. After gentle aspiration, 3 mL of solution is injected in a fanlike distribution.

Ultrasound-Guided Technique

Figure 20-4 To anesthetize the mucosa overlying the inferior alveolar sulcus, the lower lip is pulled downward, and a cotton ball soaked in 10% cocaine solution or 2% viscous lidocaine is placed into the alveolar sulcus, just above the mental foramen.

The patient is placed in the supine position. A total of 3 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for mental neuralgia, facial trauma, or other painful conditions involving the mental nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The mental foramen on the affected side is then identified by palpation. The lower lip is retracted and a cotton ball soaked in 10% cocaine solution or 2% viscous lidocaine is placed in the alveolar sulcus, just above the mental foramen (see Fig. 20-4). A highfrequency linear ultrasound transducer is placed in the

Mental nerve

Mental foramen

Figure 20-5

Proper needle trajectory for mental nerve block via the intraoral approach.

74

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nerve. After adequate topical anesthesia of the mucosa is obtained, a 25-gauge, 11 2-inch needle is advanced through the anesthetized mucosa toward the mental foramen (see Fig. 20-5). A paresthesia may be elicited, and the patient should be warned of such. After gentle aspiration, 3 mL of solution is injected in a fanlike distribution.

SIDE EFFECTS AND COMPLICATIONS

Figure 20-6 A high-frequency linear ultrasound transducer is placed in the transverse position over the previously identified mental foramen and a 25-gauge, 1 1 2-inch needle is advanced through the anesthetized mucosa toward the mental foramen. transverse position over the previously identified mental foramen and a sonogram is taken (Figs. 20-6 and 20-7). The mental foramen will be easily identified as a discontinuity of the hyperechoic mandible. Color Doppler imaging may also be used to identify the mental artery, which exits the mental foramen along with the mental

The face is highly vascular, and the pain specialist should carefully calculate the total milligram dosage of local anesthetic that may be given safely, especially if bilateral nerve blocks are being performed. This vascularity gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable riskto-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20-minute periods after the block also decreases the amount of postprocedure pain and bleeding the patient may experience.

Mental nerve

Figure 20-7

Transverse ultrasound image demonstrating the mental foramen, which appears as a discontinuity of mandible.

Clinical Pearls Mental nerve block is useful in the palliation of pain secondary to facial trauma and neuropathic pain involving the mental nerve. In the pediatric population and in patients requiring repair of facial lacerations, the intraoral approach to blockade of the mental nerve should be considered. When the intraoral approach is used in children, the child’s mother or father can actually place the anesthetic-soaked cotton ball in the alveolar sulcus under the pain management specialist’s direction.

The pain management specialist should carefully examine the patient before performing mental nerve block to identify preexisting neural compromise because the mental nerve is especially vulnerable to blunt trauma owing to the acute angle at which it exits the mental foramen. This preblock assessment helps identify subtle neurologic changes that might subsequently be erroneously attributed to the block.

C H A P T E R

21

Inferior Alveolar Nerve Block

CPT-2015 Code Unilateral Bilateral Neurolytic

64400 64400-50 64600

Relative Value Units Unilateral Bilateral Neurolytic

5 10 20

INDICATIONS Inferior alveolar nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the inferior alveolar nerve, including post-traumatic neuralgias and pain secondary to intraoral malignancies. Inferior alveolar nerve block is especially useful in providing surgical anesthesia in the distribution of the inferior alveolar nerve for lesion removal, dental surgery, and laceration repair.

affecting the inferior alveolar nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. Neurolytic blocks using small amounts of 6.5% aqueous phenol can be performed for intractable pain secondary to malignancy. The anterior margin of the mandible just above the last molar on the affected side is identified by palpation (Fig. 21-3). Topical anesthesia of the gingiva overlying this area is then obtained with either 10% cocaine solution or 2% viscous lidocaine applied with a 31 2 -inch cottontipped applicator. The patient is then asked to slightly close his or her mouth to relax the pterygoid muscles. After adequate topical anesthesia of the mucosa is obtained, a 25-gauge, 2-inch needle is advanced submucosally through the anesthetized area along the inner

CLINICALLY RELEVANT ANATOMY The inferior alveolar nerve arises from fibers of the mandibular nerve. The inferior alveolar nerve passes inferiorly to enter the mandibular canal (Fig. 21-1). The nerve travels forward through the body of the mandible, providing sensory innervation to the molars and premolars as well as their associated gingiva. As the inferior alveolar nerve approaches the mental foramen, it divides into two branches. The incisor branch provides sensory innervation to the canines and incisors. The mental branch passes through the mental foramen to provide sensory innervation to the lower lip and corresponding gingival surface. The lingual and buccal nerves lie just medial to the inferior alveolar nerve and are subject to trauma during inferior alveolar nerve block (Fig. 21-2).

Mandibular nerve Mandibular foramen

Mandibular canal

TECHNIQUE Landmark and Fluoroscopically Guided Technique The patient is placed in a supine position with the mouth wide open. A total of 5 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for neuralgias involving the inferior alveolar nerve, facial trauma, or other painful or inflammatory conditions

Figure 21-1 Anatomy of the inferior alveolar branch of the mandibular nerve. (From Waldman SD: Atlas of Pain Management Injection Techniques, 3rd ed. Philadelphia, Saunders, 2013.) 75

21

INFERIOR ALVEOLAR NERVE BLOCK

ABSTRACT

KEY WORDS

The inferior alveolar nerve arises from fibers of the mandibular nerve. The inferior alveolar nerve passes inferiorly to enter the mandibular canal (Fig. 21-1). The nerve travels forward through the body of the mandible, providing sensory innervation to the molars and premolars as well as their associated gingiva. As the inferior alveolar nerve approaches the mental foramen, it divides into two branches. The incisor branch provides sensory innervation to the canines and incisors. The mental branch passes through the mental foramen to provide sensory innervation to the lower lip and corresponding gingival surface.

acute herpes zoster inferior alveolar nerve inferior alveolar nerve block mandibular division of the trigeminal nerve

75.e1

mandibular nerve post-traumatic neuralgia trigeminal nerve

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Buccal nerve Mandibular nerve Lingual nerve

Inf. alveolar n.

Mandibular foramen

Figure 21-4 Proper needle trajectory for inferior alveolar nerve block. Inf., Inferior; n., nerve. Figure 21-2

Anatomy of the mandibular nerve and its relationship to the lingual and buccal nerves. (From Waldman SD: Atlas of Pain Management Injection Techniques, 3rd ed. Philadelphia, Saunders, 2013.)

surface of the mandible (Figs. 21-4 and 21-5). A paresthesia may be elicited, and the patient should be warned of such. Three to 5 mL of solution is injected as the needle is slowly advanced. Fluoroscopy can be used in patients in whom identification of anatomic landmarks is difficult (Fig. 21-6).

Ultrasound-Guided Technique The patient is placed in a supine position with the mouth wide open. A total of 5 mL of local anesthetic is drawn

Figure 21-3

The anterior margin of the mandible just above the last molar on the affected side is identified by palpation. (From Waldman SD: Atlas of Pain Management Injection Techniques, 3rd ed. Philadelphia, Saunders, 2013.)

Figure 21-5

Advancement of the needle for mandibular nerve block.

21

INFERIOR ALVEOLAR NERVE BLOCK

77

Figure 21-7

For ultrasound-guided inferior alveolar nerve block, a small hockey stick ultrasound transducer is placed axially against the pterygomandibular raphe at the level of the occlusal surface of the mandible. (From Chanpong B, Tang R, Sawka A, et al: Real-time ultrasonographic visualization for guided inferior alveolar nerve injection. Oral Surg Oral Med Oral Pathol Oral Radiol 115[2]:272-276, 2013.)

Figure 21-6

Needle tip in proximity to the inferior alveolar nerve.

up in a 10-mL sterile syringe. When the treatment is for neuralgias involving the inferior alveolar nerve, facial trauma, or other painful or inflammatory conditions affecting the inferior alveolar nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. Neurolytic blocks using small amounts of 6.5% aqueous phenol can be performed for intractable pain secondary to malignancy. The anterior margin of the mandible just above the last molar on the affected side is identified by palpation (see Fig. 21-3). Topical anesthesia of the gingiva overlying this area is then obtained with either 10% cocaine solution or 2% viscous lidocaine applied using a 31 2 -inch cottontipped applicator. A small hockey stick ultrasound transducer is placed axially against the pterygomandibular raphe at the level of the occlusal surface of the mandible (Fig. 21-7). The ultrasound transducer is then rotated until the mandibular ramus is identified (Fig. 21-8). The ultrasound transducer is then moved in a caudad direction until the inferior alveolar nerve is identified (Fig. 21-9). The nerve has a triangular fascicular appearance. The patient is then asked to slightly close his or her mouth to relax the pterygoid muscles. A 25-gauge, 2-inch needle is advanced submucosally through the anesthetized area along the inner surface of the mandible under real-time ultrasound guidance. A paresthesia may be elicited, and the patient should be warned of such. Three to 5 mL of solution is injected as the needle is slowly advanced.

SIDE EFFECTS AND COMPLICATIONS The face is highly vascular, and the pain management specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely, especially

if bilateral nerve blocks are being performed. This vascularity gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable risk-to-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. The proximity of the lingual and buccal nerves to the path of the needle during a standard landmark-based inferior alveolar block injection and the large degree of anatomic variability in nerve position makes lingual and buccal nerve injury a distinct possibility (Fig. 21-10).

A

Figure 21-8 Ultrasound image demonstrating the mandibular ramus (A) and inferior alveolar nerve (arrow). (From Chanpong B, Tang R, Sawka A, et al: Real-time ultrasonographic visualization for guided inferior alveolar nerve injection. Oral Surg Oral Med Oral Pathol Oral Radiol 115[2]:272-276, 2013.)

Injectate

Inferior alveolar nerve

A

Inferior alveolar nerve

B

Figure 21-9 Ultrasound image demonstrating the (A) inferior alveolar nerve (arrow). B, Injectate surrounding nerve. (From Chanpong B, Tang R, Sawka A, et al: Real-time ultrasonographic visualization for guided inferior alveolar nerve injection. Oral Surg Oral Med Oral Pathol Oral Radiol 115[2]:272-276, 2013.) Clinical Pearls

Lingual nerve Inferior alveolar nerve Lingula Nerve to mylohyoid

Figure 21-10

The proximity of the lingual and buccal nerves to the path of the needle during a standard landmark-based inferior alveolar block injection and the large degree of anatomic variability in nerve position makes lingual and buccal nerve injury a distinct possibility. (From Morris CD, Rasmussen J, Throckmorton GS, et al: The anatomic basis of lingual nerve trauma associated with inferior alveolar block injections. J Oral Maxillofac Surg 68[11]:2833-2836, 2010.)

Inferior alveolar nerve block is useful in the palliation of pain secondary to facial trauma and neuropathic pain involving the inferior alveolar nerve. In the pediatric population and in patients requiring repair of intraoral lacerations, topical anesthesia of the mucosa should be considered before the local anesthetic is injected. When the technique is used in children, the child’s mother or father can hold the anestheticsoaked cotton-tipped applicator in place under the pain management specialist’s direction before injection of solution. Care should be taken to have the patient gently close his or her mouth before injection to avoid trauma to the pterygoid muscles, which can lead to significant postblock pain (Fig. E21-1).

21

Figure E21-1

INFERIOR ALVEOLAR NERVE BLOCK

78.e1

T2-weighted magnetic resonance image showing edema around the medial pterygoid muscle on the left (arrow). (From Smyth J, Marley J: An unusual delayed complication of inferior alveolar nerve block. Br J Oral Maxillofac Surg 48[1]:51-52, 2010.)

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C H A P T E R

22

Auriculotemporal Nerve Block CPT-2015 Code Unilateral Bilateral Neurolytic

Relative Value Units 64450 64450-50 64640

Unilateral Bilateral Neurolytic

10 20 20

78.e2

SECTION I

HEAD

ABSTRACT

KEY WORDS

Auriculotemporal nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the auriculotemporal nerve, including post-traumatic neuralgia, atypical facial pain, acute herpes zoster of the external auditory meatus, and pain secondary to malignancy. Auriculotemporal nerve block is also used to treat Frey’s syndrome. In addition, auriculotemporal nerve block is useful in providing surgical anesthesia for lesion removal and laceration repair in areas subserved by the auriculotemporal nerve.

auriculotemporal nerve auriculotemporal nerve block complications of parotid surgery

Frey’s syndrome gustatory sweating parotid gland parotid surgery

22

AURICULOTEMPORAL NERVE BLOCK

79

INDICATIONS Auriculotemporal nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the auriculotemporal nerve, including post-traumatic neuralgia, atypical facial pain involving the temporomandibular joint, acute herpes zoster involving the external auditory meatus, and pain secondary to malignancy. Auriculotemporal nerve block is also used to treat Frey’s syndrome (Fig. 22-1). In addition, this technique is useful in providing surgical anesthesia in the distribution of the auriculotemporal nerve for lesion removal and laceration repair.

CLINICALLY RELEVANT ANATOMY The auriculotemporal nerve arises from fibers of the mandibular nerve. The auriculotemporal nerve courses upward through the parotid gland, passing between the temporomandibular joint and the external auditory meatus, where it gives off branches that provide sensory innervation to the temporomandibular joint and portions of the pinna of the ear and the external auditory meatus (Fig. 22-2). Ascending over the origin of the zygomatic arch, the auriculotemporal nerve continues upward along with the temporal artery, providing sensory innervation to the temporal region and lateral scalp.

Figure 22-1 Patients with Frey’s syndrome experience postgustatory unilateral hyperhidrosis and flushing of the malar region. (From Waldman SD: Atlas of Pain Management Injection Techniques, 3rd ed. Philadelphia, Saunders, 2013.)

TECHNIQUE Landmark and Fluoroscopically Guided Technique The patient is placed in the supine position with the head turned away from the side to be blocked. A total of 5 mL

Posterior temporal nerve

Infraorbital nerve

Auriculotemporal nerve

Buccal branch of the temporal nerve

Facial nerve

Buccinator nerve

Inferior alveolar (dental) nerve

Figure 22-2 Anatomy of the auriculotemporal nerve. (From Barral JP, Croibier A: Mandibular nerve. In Manual Therapy for the Cranial Nerves. Edinburgh, Churchill Livingstone, 2009, pp 139-146.)

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V3

Figure 22-4 Proper transverse position of the high-frequency linear ultrasound transducer over the temporal artery for ultrasound-guided auriculotemporal nerve block. Sup. temporal artery Auriculotemporal nerve

Figure 22-3 Proper needle trajectory for auriculotemporal nerve block. Sup., Superficial.

of local anesthetic is drawn up in a 12-mL sterile syringe. When the treatment is for painful conditions involving the auriculotemporal nerve that may have an inflammatory component, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The temporal artery is identified at a point just above the origin of the zygoma on the affected side. After preparation of the skin with antiseptic solution, a 25-gauge, 1 1 2-inch needle is inserted at this point and is advanced perpendicularly until the needle approaches the periosteum of the underlying bone (Fig. 22-3). A paresthesia may be elicited, and the patient should be warned of such. After gentle aspiration, 3 mL of solution is injected. The needle is then redirected in a cephalad trajectory, and after careful aspiration, the remaining 2 mL of solution is injected in a fanlike manner.

Ultrasound-Guided Technique The patient is placed in a supine position with the head turned away from the side to be blocked. A total of 5 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for neuralgias involving the auriculotemporal nerve, facial trauma, or other painful or inflammatory conditions affecting the auriculotemporal nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. Neurolytic blocks using small amounts of 6.5% aqueous phenol can be performed for intractable pain secondary to malignancy.

The temporomandibular joint and the origin of the zygoma are identified by palpation. The temporomandibular joint is identified by having the patient open and close the mouth. The pulse of the temporal artery should be easily palpated just above this area. The skin overlying the pulsation of the temporomandibular joint is prepared with antiseptic solution, with care being taken to avoid spillage into the eye and acoustic auditory meatus. A high-frequency linear ultrasound transducer is placed in the transverse position over the previously identified pulsation of the temporal artery and a sonogram is taken (Fig. 22-4). Color Doppler imaging may also be used to identify the temporal artery if palpation of the pulsations is difficult (Fig. 22-5). The auriculotemporal nerve lies adjacent to the temporal artery and is then identified (see Fig. 22-5). The course of the nerve can also be delineated by rotating the ultrasound transducer from the transverse to the longitudinal position. Once the auriculotemporal nerve is identified, a 22-gauge, 1 1 2-inch needle is inserted approximately 1 cm below the inferior border of the ultrasound transducer and the needle is advanced perpendicularly to the transducer using an out-of-plane approach until the needle is in proximity to the nerve. A paresthesia may be elicited, and the patient should be warned of such. After gentle aspiration, 3 mL of solution is slowly injected. The needle is then redirected in a cephalad trajectory, and after careful aspiration, the remaining 2 mL of solution is injected in a fanlike manner around the auriculotemporal nerve as it continues its ascent. The needle is removed and pressure is placed on the injection site to avoid bleeding complications.

SIDE EFFECTS AND COMPLICATIONS The scalp is highly vascular, and the auriculotemporal nerve is in close proximity to the temporal artery at the point at which the nerve is blocked. Therefore, the pain management specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely, especially if bilateral nerve blocks are being

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Auriculotemporal nerve S. temporal a.

Figure 22-5 Transverse ultrasound image with color Doppler demonstrating the superficial temporal artery and the auriculotemporal nerve. a., Artery; S., superficial. performed. This vascularity gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical

situation indicates a favorable risk-to-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20-minute periods after the block also decreases the amount of postprocedure pain and bleeding the patient may experience.

Figure 22-6

Figure 22-7

Minor’s starch-iodine test for Frey’s syndrome. Discoloration occurs in the affected area after gustatory stimulation. (From Gillespie MB, Eisele DW: Complications of surgery of the salivary glands. In Eisele DW, Smith RV, editors: Complications in Head and Neck Surgery, 2nd ed. Philadelphia, Mosby, 2009, pp 221-239.)

Simple assessment for Frey’s syndrome using facial tissue. The affected area is demarcated by the wet portion of the tissue. (From Gillespie MB, Eisele DW: Complications of surgery of the salivary glands. In Eisele DW, Smith RV, editors: Complications in Head and Neck Surgery, 2nd ed. Philadelphia, Mosby, 2009, pp 221-239.)

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Figure 22-8 Ultrasound-guided botulinum toxin injection for postparotidectomy salivary fistula and associated hyperhidrosis. (From Gillespie MB, Eisele DW: Complications of surgery of the salivary glands. In Eisele DW, Smith RV, editors: Complications in Head and Neck Surgery, 2nd ed. Philadelphia, Mosby, 2009, pp 221-239.) Clinical Pearls Auriculotemporal nerve block is especially useful in the palliation of pain secondary to acute herpes zoster involving the geniculate ganglion, such as Ramsay Hunt syndrome, when combined with facial nerve block. The use of tepid aluminum acetate soaks helps dry weeping lesions of the external auditory meatus and makes the patient more comfortable. Frey’s syndrome is a constellation of symptoms including unilateral hyperhidrosis and flushing of the malar region and pinna of the ear that occurs when the patient eats or drinks anything that stimulates the parotid gland to produce saliva (see Fig. 22-1). Also known as auriculotemporal syndrome, Baillarger’s syndrome, Dupuy’s syndrome, salivosudoriparous syndrome, and gustatory sweating syndrome, this disorder usually occurs 2 to 13 months after surgery, open trauma, or infection of the parotid gland. It is thought to be due to improper regeneration of the sympathetic and parasympathetic nerves subserving the parotid gland and affected anatomic areas. Frey’s syndrome can be diagnosed using Minor’s starch-iodine test, which is performed by applying a solution consisting of 3 g of iodine, 20 g of castor oil, and 200 mL of absolute alcohol to the affected area and then letting the solution dry. The affected area is then dusted with starch powder and the patient is given a strong sialogogue such as a dill pickle to induce postgustatory sweating. In the areas of hyperhidrosis, the starch and iodine bind in a Lugol reaction, with the areas of hyperhidrosis turning a dark purplish blue color (Fig. 22-6). If the reagents for Minor’s starch-iodine test are not readily available, the skin overlying the area of hyperhidrosis is covered with a single ply of a two-ply facial tissue and a strong sialogogue is given (Fig. 22-7).

The severity of symptoms associated with Frey’s syndrome can range from mild to debilitating. Although the incidence of Frey’s syndrome after parotid surgery can be decreased by careful attention to surgical technique, including careful identification and preservation of the auriculotemporal nerve and creation of a thick skin flap when parotidectomy is performed, approximately 5% of patients undergoing parotid surgery will experience some degree of symptoms. For patients with mild symptoms, reassurance and the use of topical antiperspirants such as 20% aluminum chloride in alcohol or topical scopolamine cream may be all that is required. For more severe symptoms, blockade of the auriculotemporal nerve may provide significant relief. Auriculotemporal nerve block may also be combined with intradermal injection of botulinum toxin A in the areas of hyperhidrosis. Ultrasound-guided injections of botulinum toxin into residual parotid tissue still innervated by the auriculotemporal nerve can also be considered in patients with Frey’s syndrome (Fig. 22-8). Auriculotemporal nerve block is also useful in the management of atypical facial pain syndromes involving the temporomandibular joint. Blockade of the auriculotemporal nerve allows the physical therapist to more aggressively treat temporomandibular joint dysfunction. It should be remembered that in the absence of a clear cause of the patient’s pain, careful evaluation, including careful history taking and physical examination as well as appropriate medical imaging, is mandatory to avoid medical disasters due to failure to recognize the correct diagnosis (Fig. E22-1).

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B

Figure E22-1 Auriculotemporal nerve involvement. Axial postcontrast fat-saturated T1-weighted images for a patient with a poorly defined carcinoma. Note abnormal enhancement in the region of the right auriculotemporal nerve (long solid arrow). Perineural tumor extension has occurred along the nerve to V2 and V3 segments of the right trigeminal nerve, with tumor in the right foramen rotundum (short solid arrow) and cavernous sinus, and tumor extension along the facial nerve (dashed arrow). (From Friedman ER, Saindane AM: Pitfalls in the staging of cancer of the major salivary gland neoplasms. Neuroimaging Clin N Am 23[1]:107-122, 2013.)

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Greater Auricular Nerve Block CLINICALLY RELEVANT ANATOMY

CPT-2015 Code Unilateral Bilateral Neurolytic

64450 64450-50 64640

Relative Value Units Unilateral Bilateral Neurolytic

8 12 20

The greater auricular nerve arises from fibers of the primary ventral ramus of the second and third cervical nerves. The greater auricular nerve pierces the fascia inferior and lateral to the lesser occipital nerve (Fig. 23-1). It passes superiorly and forward and then curves around the sternocleidomastoid muscle, moving more superficially to provide cutaneous sensory innervation to the ear, external auditory canal, angle of the jaw, and skin overlying a portion of the parotid gland (Fig. E23-1).

TECHNIQUE

INDICATIONS

Landmark and Fluoroscopically Guided Technique

Greater auricular nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the greater auricular nerve, including greater auricular neuralgia and pain secondary to herpes zoster. This technique is also useful in providing surgical anesthesia in the distribution of the greater auricular nerve for lesion removal and laceration repair.

The patient is placed in a sitting position with the cervical spine flexed and the forehead on a padded bedside table. A total of 5 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for greater auricular neuralgia or other painful conditions involving the greater auricular nerve, a total of 80 mg of depotsteroid is added to the local anesthetic with the first

Ext. auditory br. of greater auricular n.

Mastoid process

Parotid gland Sternocleidomastoid m.

Post. br. of greater auricular n. Ant. br. of greater auricular n. Ventral rami of 2nd cervical n. Ventral rami of 3rd cervical n.

Figure 23-1

Anatomy of the greater auricular nerve. Ant., Anterior; br., branch; Ext., external; m., muscle; n., nerve; Post., posterior.

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ABSTRACT

KEY WORDS

The greater auricular nerve arises from fibers of the primary ventral ramus of the second and third cervical nerves. Greater auricular nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved by the greater auricular nerve, including greater auricular neuralgia and pain secondary to herpes zoster. This technique is also useful in providing surgical anesthesia in the distribution of the greater auricular nerve for lesion removal and laceration repair. Because leprosy often affects the greater auricular nerve, the clinician should have a high index of suspicion for the diagnosis of leprosy in any patient with a thickened and tender greater auricular nerve.

acute herpes zoster greater auricular nerve greater auricular nerve block Hansen’s disease

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leprosy Ramsay Hunt syndrome neuralgia ultrasound-guided greater auricular nerve block

A

Trapezius

SCM

B

Figure E23-1 The greater auricular nerve passes superiorly and forward and then curves around the sternocleidomastoid muscle (SCM), where it is amenable to neural blockade. A, Identification of the greater auricular nerve on the superficial border of the SCM exposed after elevation of the subplatysmal flap. B, The spinal accessory nerve exiting the SCM being traced to the trapezius through the fascia. (From Klein JD, Myers J, Kupferman ME: Posterolateral neck dissection: preoperative considerations and intraoperative technique, Oper Tech Otolaryngol Head Neck Surg 24[1]:24-29, 2013.)

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block, and 40 mg of depot-steroid is added with subsequent blocks. The mastoid process on the affected side is then identified by palpation. After preparation of the skin with antiseptic solution, a 22-gauge, 1 1 2-inch needle is inserted at the level of the mastoid process and is advanced perpendicularly until the needle approaches the periosteum of the underlying bone (Fig. 23-2). A paresthesia may be elicited, and the patient should be warned of such. The needle is then redirected toward the lobe of the ear. After gentle aspiration, 3 mL of solution is injected in a fanlike distribution. The needle is then redirected medially, and after careful aspiration, the remaining 2 mL of solution is injected in a fanlike manner (Fig. 23-3). Fluoroscopy can be used to aid in needle placement in patients in whom the landmarks are difficult to identify (Fig. 23-4). Mastoid process Sternocleidomastoid m.

Post. br. of greater auricular n. Ant. br. of greater auricular n.

Figure 23-2 Proper needle trajectory for greater auricular nerve block. Ant., Anterior; br., branch; m., muscle; n., nerve; Post., posterior.

Ultrasound-Guided Technique The patient is placed in a supine position with the head turned away from the side to be blocked. A total of 3 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for inflammatory conditions involving the greater auricular nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. Neurolytic blocks using small amounts of 6.5% aqueous phenol can be performed for intractable pain secondary to malignancy. The posterior border of the sternocleidomastoid muscle at the level of the cricoid notch is then identified by palpation. The skin is prepared with antiseptic solution and a high-frequency linear ultrasound transducer is placed in

Ext. auditory br. of greater auricular n.

Mastoid process

Post. br. of greater auricular n.

Figure 23-3

Ant. br. of greater auricular n.

Proper needle placement for greater auricular nerve block. Ant., Anterior; br., branch; Ext., external; n., nerve; Post., posterior.

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85

Superficial greater auricular nerve Sternocleidomastoid muscle

Deep greater auricular nerve

Carotid artery

Jugular vein

Figure 23-6 Ultrasound image demonstrating both the superficial and deep portions of the greater auricular nerve and the adjacent carotid artery and jugular vein. Figure 23-4

Needle tip in proximity to the auriculotemporal nerve.

a transverse oblique plane at a right angle to the previously identified posterior border of the sternocleidomastoid muscle (Fig. 23-5). A sonogram is taken, which will demonstrate the greater auricular nerve at two points along its path: (1) deep to the sternocleidomastoid muscle, and (2) in its superficial position as it loops around the superficial margin of the sternocleidomastoid muscle (Fig. 23-6). It is at the point at which the nerve loops around the superficial margin of the sternocleidomastoid muscle that the greater auricular nerve is easily blocked using ultrasound guidance. Before needle placement, the clinician should note the relative positions of the carotid

artery and adjacent jugular vein to avoid inadvertent intravascular injection (see Fig. 23-6). Color Doppler imaging can aid in identification of these vascular structures. After identification of the superficial portion of the greater auricular nerve, a 22-gauge, 1 1 2-inch needle is advanced under real-time ultrasound guidance using an in-plane approach from the lateral border of the ultrasound transducer. A paresthesia may be elicited, and the patient should be warned of such. After the needle tip is in proximity to the superficial portion of the greater auricular nerve, gentle aspiration is carried out and 3 mL of solution is slowly injected. The needle is then removed and pressure is placed on the injection site.

SIDE EFFECTS AND COMPLICATIONS

Figure 23-5

Proper placement of the high-frequency linear ultrasound transducer for ultrasound-guided block of the greater auricular nerve.

The scalp is highly vascular, and the pain management specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely, especially if bilateral nerve blocks are being performed. This vascularity gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable risk-to-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20-minute periods after the block also decreases the amount of postprocedure pain and bleeding the patient may experience.

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Clinical Pearls Greater auricular nerve block is especially useful in the palliation of pain secondary to acute herpes zoster involving the geniculate ganglion, such as Ramsay Hunt syndrome, when combined with facial nerve block. Use of tepid aluminum acetate soaks helps dry weeping lesions in the external auditory meatus and makes the patient more comfortable. Since leprosy often affects the greater auricular nerve, the clinician should have a high index of suspicion for the diagnosis of leprosy in any patient with a thickened and tender greater auricular nerve (Fig. 23-7).

Figure 23-7 Thickening of the greater auricular nerve caused by tuberculoid leprosy (Hansen’s disease) in a young Congolese boy. (From Walsh DS, Meyers WM: Leprosy. In Guerrant R, Walker D, Weller P, editors: Tropical Infectious Diseases: Principles, Pathogens and Practice, 3rd ed. Edinburgh, Saunders, 2011, pp 253-260.)

C H A P T E R

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Glossopharyngeal Nerve Block: Extraoral Approach CPT-2015 Code Unilateral Neurolytic

64999 64640

Relative Value Units Unilateral Neurolytic

12 20

INDICATIONS Glossopharyngeal nerve block with local anesthetic not only can provide surgical anesthesia but also can be used as a diagnostic tool when differential neural blockade is performed on an anatomic basis in the evaluation of head and facial pain. If destruction of the glossopharyngeal

nerve is being considered, this technique can be used in a prognostic manner to indicate the degree of motor and sensory impairment that the patient may experience. Glossopharyngeal nerve block with local anesthetic may be used for palliation in acute pain emergencies, including glossopharyngeal neuralgia and cancer pain, during the wait for pharmacologic, surgical, and antiblastic methods to take effect. Glossopharyngeal nerve block is also useful as an adjunct in awake endotracheal intubation. Destruction of the glossopharyngeal nerve is indicated for the palliation of cancer pain, including pain secondary to invasive tumors of the posterior tongue, hypopharynx, and tonsils. This technique is especially useful in management of the pain of glossopharyngeal neuralgia in those patients for whom medical therapies have not been effective and in patients who are not candidates for surgical microvascular decompression of the glossopharyngeal nerve (Fig. 24-1).

Figure 24-1

Illustrative clinical case. Oblique transverse three-dimensional magnetic resonance image for a 60-year-old man with right-sided neurovascular compression. The image shows that the glossopharyngeal nerve (thin white arrow) is pushed with heavy distortion by the vertebral artery (thin black arrow). White arrowheads indicate the jugular foramen and swallow-tailed arrow indicates the internal carotid artery. (From Liang C, Du Y, Xu J, et al: MR imaging of the cisternal segment of the posterior group of cranial nerves: neurovascular relationships and abnormal changes. Eur J Radiol 75[1]:57-63, 2010.)

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ABSTRACT

KEY WORDS

The glossopharyngeal nerve exits from the jugular foramen in proximity to the vagus and accessory nerves and the internal jugular vein. The glossopharyngeal nerve contains both motor and sensory fibers. The motor fibers innervate the stylopharyngeus muscle. The sensory portion of the nerve innervates the posterior third of the tongue, palatine tonsil, and mucous membranes of the mouth and pharynx. Special visceral afferent sensory fibers transmit information from the taste buds of the posterior third of the tongue. Information from the carotid sinus and body that helps control blood pressure, pulse, and respiration is carried via the carotid sinus nerve, which is a branch of the glossopharyngeal nerve. Parasympathetic fibers pass via the glossopharyngeal nerve to the otic ganglion. Postganglionic fibers from the ganglion carry secretory information to the parotid gland. Glossopharyngeal nerve block can be used for prognosis and diagnosis as well as for treatment of acute pain emergencies such as glossopharyngeal neuralgia. This technique is also useful in the palliation of cancer pain.

cancer pain glossopharyngeal nerve glossopharyngeal nerve block

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glossopharyngeal neuralgia microvascular decompression

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CLINICALLY RELEVANT ANATOMY

Figure 24-2 Metastatic small cell carcinoma of the right palatine tonsil. (From Hisa Y, Yasuda N, Murakami M: Small cell carcinoma of the lung metastatic to the palatine tonsil. Otolaryngol Head Neck Surg 116[4]:563-564, 1997.) Because of the desperate condition of many patients who have aggressively invasive head and face malignancies, blockade of the glossopharyngeal nerve using a 25-gauge needle may be carried out in the presence of coagulopathy or anticoagulant therapy, albeit with an increased risk of ecchymosis and hematoma formation (Fig. 24-2).

The glossopharyngeal nerve contains both motor and sensory fibers. The motor fibers innervate the stylopharyngeus muscle. The sensory portion of the nerve innervates the posterior third of the tongue, palatine tonsil, and mucous membranes of the mouth and pharynx. Special visceral afferent sensory fibers transmit information from the taste buds of the posterior third of the tongue. Information from the carotid sinus and body that helps control blood pressure, pulse, and respiration is carried via the carotid sinus nerve, which is a branch of the glossopharyngeal nerve. Parasympathetic fibers pass via the glossopharyngeal nerve to the otic ganglion. Postganglionic fibers from the ganglion carry secretory information to the parotid gland. The glossopharyngeal nerve exits from the jugular foramen in proximity to the vagus and accessory nerves and the internal jugular vein (Fig. 24-3). All three nerves lie in the groove between the internal jugular vein and internal carotid artery (Fig. 24-4). The key landmark for extraoral glossopharyngeal nerve block is the styloid process of the temporal bone. This osseous process represents the calcification of the cephalad end of the stylohyoid ligament. Although usually easy to identify, the styloid process may be difficult to locate with the exploring needle if ossification is limited.

Trigeminal ganglion

External acoustic meatus Hypoglossal nerve

Lingual nerve

Glossopharyngeal nerve

Stylohyoid muscle Infrahyoid muscles

Figure 24-3

Anatomy of the glossopharyngeal nerve. (From Barral JP, Croibier A: Glossopharyngeal nerve. In Manual Therapy for the Cranial Nerves. Edinburgh, Churchill Livingstone, 2009, pp 181-189.)

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GLOSSOPHARYNGEAL NERVE BLOCK: EXTRAORAL APPROACH

Styloid process

89

Mastoid Styloid process Mandibular angle

Glossopharyngeal nerve Figure 24-4 The glossopharyngeal nerve exits from the jugular foramen in proximity to the vagus and accessory nerves and the internal jugular vein. All three nerves lie in the groove between the internal jugular vein and internal carotid artery.

Figure 24-5 An imaginary line is visualized running from the mastoid process to the angle of the mandible.

TECHNIQUE Landmark and Fluoroscopically Guided Technique The patient is placed in the supine position. An imaginary line is visualized running from the mastoid process to the angle of the mandible (Fig. 24-5). The styloid process should lie just below the midpoint of this line. The skin is prepared with antiseptic solution. Fluoroscopy may assist the clinician in identifying the styloid process (Fig. 24-6). A 22-gauge, 11 2 -inch needle attached to a 10-mL syringe is advanced at this midpoint location in a plane perpendicular to the skin. The styloid process should be encountered within 3 cm. After contact is made, the needle is withdrawn and walked off the styloid process posteriorly (Figs. 24-6, 24-7, and 24-8). As soon as bony contact is lost and careful aspiration reveals no blood or cerebrospinal fluid, 7 mL of 0.5% preservative-free lidocaine combined with 80 mg of methylprednisolone is injected in incremental doses. Subsequent daily nerve blocks are carried out in a similar manner, with 40 mg of methylprednisolone substituted for the initial 80-mg dose. This approach also may be used to treat breakthrough pain in patients who previously experienced adequate pain control with oral medications.

Styloid process

Glossopharyngeal nerve

Ultrasound-Guided Technique The patient is placed in the supine position with the head turned away from the side to be blocked. An imaginary line is visualized running from the mastoid process to the angle of the mandible (see Fig. 24-5). The styloid process should lie just below the midpoint of this line. The skin

Figure 24-6

A 22-gauge, 1 1 2-inch needle attached to a 10-mL syringe is advanced at a location midpoint between the mastoid process and the angle of the mandible in a plane perpendicular to the skin. The styloid process should be encountered within 3 cm. After contact is made, the needle is withdrawn and walked off the styloid process posteriorly.

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Figure 24-9

Proper transducer placement for ultrasound-guided glossopharyngeal nerve block via the extraoral approach.

Figure 24-7 Anteroposterior view of the needle tip just behind the posterior aspect of the styloid process. is prepped with antiseptic solution. A total of 5 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for pain subserved by the glossopharyngeal nerve that is thought to have an inflammatory basis, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depotsteroid is added with subsequent blocks. Neurolytic blocks using small amounts of 6.5% aqueous phenol can be performed for intractable pain secondary to malignancy. A high-frequency linear ultrasound transducer is

then placed over the previously identified location of the styloid process and a sonogram is taken (Fig. 24-9). The styloid process, glossopharyngeal nerve, and adjacent carotid artery and jugular vein are identified (Fig. 24-10). A 22-gauge, 31 2-inch styletted spinal needle is then advanced under real-time ultrasound guidance toward the styloid process using an out-of-plane approach. The styloid process should be encountered within approximately 3 cm. After contact with the styloid process is made, the needle is withdrawn slightly out of the periosteum or substance of the calcified ligament and under real-time ultrasound guidance is walked off the posterior aspect of the styloid process/ligament and advanced slightly so the needle tip rests in proximity to the glossopharyngeal nerve. The glossopharyngeal nerve should be identifiable adjacent to the carotid artery (see Fig. 24-10). After careful aspiration reveals no blood or cerebrospinal fluid, 3 mL of solution is injected. The needle is removed and pressure is placed on the injection site to

Glossopharyngeal nerve

Jugular vein

Carotid a.

Mastoid process Styloid process

Figure 24-8

Lateral view of the needle tip just behind the posterior aspect of the styloid process.

Figure 24-10 Ultrasound image demonstrating the relationship of the glossopharyngeal nerve to the styloid process, carotid artery, and jugular vein. a., Artery.

avoid bleeding complications. Subsequent daily nerve blocks are carried out in a similar manner.

SIDE EFFECTS AND COMPLICATIONS The major complications associated with glossopharyngeal nerve block are related to trauma to the internal jugular vein and carotid artery. Hematoma formation and intravascular injection of local anesthetic with subsequent toxicity are not uncommon complications of glossopharyngeal nerve block. Blockade of the motor portion of the glossopharyngeal nerve can result in dysphagia secondary to weakness of the stylopharyngeus muscle. If the vagus nerve is inadvertently blocked, as is often the case during glossopharyngeal nerve block, dysphonia secondary to paralysis of the ipsilateral vocal cord may occur. A reflex tachycardia secondary to vagal nerve

block is also observed in some patients. Inadvertent block of the hypoglossal and spinal accessory nerves during glossopharyngeal nerve block results in weakness of the tongue and trapezius muscle. A small percentage of patients who undergo chemical neurolysis or neurodestructive procedures of the glossopharyngeal nerve experience postprocedure dysesthesias in the area of anesthesia. These symptoms range from a mildly uncomfortable burning or pulling sensation to severe pain. When this severe postprocedure pain occurs, it is called anesthesia dolorosa. Anesthesia dolorosa can be worse than the patient’s original pain complaint and is often harder to treat. Although uncommon, infection remains an ever-present possibility, especially in the immunocompromised cancer patient. Early detection of infection is crucial to avoid potentially life-threatening sequelae.

Clinical Pearls Glossopharyngeal nerve block is a simple technique that can produce dramatic relief for patients suffering from the previously mentioned pain complaints. Neurolytic block with small quantities of alcohol, phenol, and glycerol has been shown to provide long-term relief for patients with glossopharyngeal neuralgia and cancer-related pain who have shown no response to more conservative treatments. Destruction of the glossopharyngeal nerve can also be carried out by creating a radiofrequency lesion under biplanar fluoroscopic guidance. As mentioned earlier, the proximity of the glossopharyngeal nerve to major vasculature makes postblock hematoma and ecchymosis a distinct possibility. Although these complications

are usually transitory, their dramatic appearance can be quite upsetting to the patient, and therefore the patient should be warned of this possibility before the procedure. The vascularity of this region also increases the incidence of inadvertent intravascular injection. Even small amounts of local anesthetic injected into the carotid artery at this level will result in local anesthetic toxicity and seizures. Incremental dosing while the patient is carefully monitored for signs of local anesthetic toxicity helps avoid this complication. It is important to remember that the clinician must diligently seek out the cause of any pain in areas subserved by the glossopharyngeal nerve to avoid clinical disaster (Fig E24-1).

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Figure E24-1 Axial T2-weighted magnetic resonance image showing a jugular fossa schwannoma in a 32-year-old woman. The sharply defined tumor centered in the right jugular foramen is well seen. The tumor is a benign schwannoma with smooth expansion of the skull base but no involvement of the right internal auditory canal. (From Stark DD, Bradley WG: Magnetic Resonance Imaging, 3rd ed. St Louis, Mosby, 1999, p 1217.)

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GLOSSOPHARYNGEAL NERVE BLOCK: INTRAORAL APPROACH

C H A P T E R

91

25

Glossopharyngeal Nerve Block: Intraoral Approach INDICATIONS

CPT-2015 Code Unilateral Neurolytic

64999 64640

Relative Value Units Unilateral Neurolytic

12 20

Glossopharyngeal nerve block via the intraoral approach is used when anatomic distortion secondary to tumor or prior surgery precludes the use of the extraoral approach. The indications are the same as for glossopharyngeal nerve block via the extraoral approach. The technique is used for surgical anesthesia and as a diagnostic tool when differential neural blockade is performed on an anatomic basis in the evaluation of head and facial pain.

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ABSTRACT

KEY WORDS

The glossopharyngeal nerve exits from the jugular foramen in proximity to the vagus and accessory nerves and the internal jugular vein. The glossopharyngeal nerve contains both motor and sensory fibers. The motor fibers innervate the stylopharyngeus muscle. The sensory portion of the nerve innervates the posterior third of the tongue, palatine tonsil, and mucous membranes of the mouth and pharynx. Special visceral afferent sensory fibers transmit information from the taste buds of the posterior third of the tongue. Information from the carotid sinus and body that helps control blood pressure, pulse, and respiration is carried via the carotid sinus nerve, which is a branch of the glossopharyngeal nerve. Parasympathetic fibers pass via the glossopharyngeal nerve to the otic ganglion. Postganglionic fibers from the ganglion carry secretory information to the parotid gland. Glossopharyngeal nerve block via the intraoral approach is used when anatomic distortion secondary to tumor or prior surgery precludes the use of the extraoral approach. Glossopharyngeal nerve block can be used for prognosis and diagnosis as well as for treatment of acute pain emergencies such as glossopharyngeal neuralgia. This technique is also useful in the palliation of cancer pain.

cancer pain glossopharyngeal nerve glossopharyngeal nerve block

glossopharyngeal neuralgia microvascular decompression

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If destruction of the glossopharyngeal nerve is being considered, this technique can be used in a prognostic manner to indicate the degree of motor and sensory impairment that the patient may experience. Glossopharyngeal nerve block with local anesthetic may be used for palliation in acute pain emergencies, including glossopharyngeal neuralgia and cancer pain, during the wait for pharmacologic, surgical, and antiblastic methods to take effect. Glossopharyngeal nerve block is also useful as an adjunct in awake endotracheal intubation. Destruction of the glossopharyngeal nerve is indicated for the palliation of cancer pain, including pain secondary to invasive tumors of the posterior tongue, hypopharynx, and tonsils (Fig. 25-1). In this setting, the intraoral approach may be preferred to avoid injection through tumor mass or distorted anatomy. This technique is especially useful in management of the pain of glossopharyngeal neuralgia in those patients for whom medical therapies have not been effective and in patients who are not candidates for surgical microvascular decompression of the glossopharyngeal nerve. Because of the desperate condition of many patients who have aggressively invasive head and face malignancies, blockade of the glossopharyngeal nerve using a 25-gauge needle may be carried out in the presence of coagulopathy or anticoagulant therapy, albeit with an increased risk of ecchymosis and hematoma formation.

CLINICALLY RELEVANT ANATOMY The key landmark for intraoral glossopharyngeal nerve block is the palatine tonsil. The glossopharyngeal nerve

Figure 25-1 Ulcerated exophytic mass on the posterior lateral border of the tongue. (From Orbak R, Bayraktar C, Kavrut F, et al: Poor oral hygiene and dental trauma as the precipitating factors of squamous cell carcinoma. Oral Oncol Extra 41[6]:109-113, 2005.) lies submucosally just medial to the palatine tonsil (Fig. 25-2). The internal carotid artery lies just posterior and lateral to the nerve, which makes inadvertent intraarterial needle placement a distinct possibility. The glossopharyngeal nerve contains both motor and sensory fibers. The motor fibers innervate the stylopharyngeus muscle. The sensory portion of the nerve innervates the posterior third of the tongue, palatine tonsil, and mucous membranes of the mouth and pharynx. Special visceral afferent sensory fibers transmit information from the taste buds of the posterior third of the tongue. Information from the carotid sinus and body that

Glossopharyngeal nerve

Palatine tonsil

Figure 25-2

The glossopharyngeal nerve lies submucosally just medial to the palatine tonsil.

25

GLOSSOPHARYNGEAL NERVE BLOCK: INTRAORAL APPROACH

93

Trigeminal ganglion

External acoustic meatus Hypoglossal nerve

Lingual nerve

Glossopharyngeal nerve

Stylohyoid muscle Infrahyoid muscles

Figure 25-3

Anatomy of the glossopharyngeal nerve. (From Barral JP, Croibier A: Glossopharyngeal nerve. In Manual Therapy for the Cranial Nerves. Edinburgh, Churchill Livingstone, 2009, pp 181-189.)

helps control blood pressure, pulse, and respiration is carried via the carotid sinus nerve, which is a branch of the glossopharyngeal nerve. Parasympathetic fibers pass via the glossopharyngeal nerve to the otic ganglion. Postganglionic fibers from the ganglion carry secretory information to the parotid gland. The glossopharyngeal nerve exits from the jugular foramen in proximity to the vagus and accessory nerves and the internal jugular vein (Fig. 25-3). All three nerves lie in the groove between the internal jugular vein and internal carotid artery. The nerve proceeds inferiorly and courses medially, where it lies submucosally behind the palatine tonsil, which allows easy access via the intraoral approach.

TECHNIQUE Landmark Technique The patient is placed in the supine position. The tongue is anesthetized with 2% viscous lidocaine. The patient opens the mouth wide, and the tongue is then retracted inferiorly with a tongue depressor or laryngoscope blade. A 22-gauge, 31 2-inch spinal needle that has been bent about 25 degrees is inserted through the mucosa at the lower lateral portion of the posterior tonsillar pillar (see Fig. 25-2). The needle is advanced approximately 0.5 cm. After careful aspiration for blood and cerebrospinal fluid, 7 mL of 0.5% preservative-free lidocaine combined with

80 mg of methylprednisolone is injected in incremental doses. Subsequent daily nerve blocks are carried out in a similar manner, with 40 mg of methylprednisolone substituted for the initial 80-mg dose.

SIDE EFFECTS AND COMPLICATIONS The major complications associated with glossopharyngeal nerve block are related to trauma to the internal jugular vein and carotid artery. Hematoma formation and intravascular injection of local anesthetic with subsequent toxicity are not uncommon after glossopharyngeal nerve block. Blockade of the motor portion of the glossopharyngeal nerve can result in dysphagia secondary to weakness of the stylopharyngeus muscle. A small percentage of patients who undergo chemical neurolysis or neurodestructive procedures of the glossopharyngeal nerve experience postprocedure dysesthesias in the area of anesthesia. These symptoms range from a mildly uncomfortable burning or pulling sensation to severe pain. When this severe postprocedure pain occurs, it is called anesthesia dolorosa. Anesthesia dolorosa can be worse than the patient’s original pain complaint and is often harder to treat. Although uncommon, infection remains an everpresent possibility, especially in the immunocompromised cancer patient. Early detection of infection is crucial to avoid potentially life-threatening sequelae.

Clinical Pearls The intraoral approach to glossopharyngeal nerve block is used when anatomic distortion secondary to tumor or prior surgery precludes the use of the extraoral approach. Glossopharyngeal nerve block is a simple technique that can produce dramatic relief for patients suffering from the previously mentioned pain complaints. Neurolytic block with small quantities of alcohol, phenol, and glycerol has been shown to provide long-term relief for patients with glossopharyngeal neuralgia and cancer-related pain who have not shown a response to more conservative treatments. Destruction of the glossopharyngeal nerve can also be carried out by creating a radiofrequency lesion under biplanar fluoroscopic guidance. As mentioned earlier, the proximity of the glossopharyngeal nerve to major vasculature makes postblock hematoma and ecchymosis a distinct possibility. Although these complications

are usually transitory, their dramatic appearance can be quite upsetting to the patient, and therefore the patient should be warned of this possibility before the procedure. The vascularity of this region also increases the incidence of inadvertent intravascular injection. Even small amounts of local anesthetic injected into the carotid artery at this level will result in local anesthetic toxicity and seizures. Incremental dosing while the patient is carefully monitored for signs of local anesthetic toxicity helps avoid this complication. It is important to remember that the clinician must diligently seek out the cause of any pain in areas subserved by the glossopharyngeal nerve to avoid clinical disaster. On physical examination, patients with compromise of the glossopharyngeal nerve may exhibit weakness of the soft palate and deviation of the uvula to the affected side (Fig. E25-1).

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Figure E25-1 Photograph showing lower cranial nerve palsy on the right side. (From Singh I, Singla S, Kumar G, et al: Isolated glossopharyngeal and vagus nerve palsy due to fracture involving the jugular foramen—report of three cases. Indian J Neurotrauma 9[2]:140-142, 2012.)

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26

Glossopharyngeal Nerve Block: Radiofrequency Lesioning CLINICALLY RELEVANT ANATOMY

CPT-2015 Code Unilateral Neurolytic

64999 64640

Relative Value Units Unilateral Neurolytic

12 20

INDICATIONS Destruction of the glossopharyngeal nerve is indicated for the palliation of cancer pain, including pain secondary to invasive tumors of the posterior tongue, hypopharynx, and tonsils. This technique is especially useful in management of the pain of glossopharyngeal neuralgia in those patients for whom medical therapies have not been effective and in patients who are not candidates for surgical microvascular decompression of the glossopharyngeal nerve. In recent years, radiofrequency lesioning has gained in popularity as the technique of choice when destruction of the glossopharyngeal nerve is indicated (Fig. 26-1).

The glossopharyngeal nerve contains both motor and sensory fibers. The motor fibers innervate the stylopharyngeus muscle. The sensory portion of the nerve innervates the posterior third of the tongue, palatine tonsil, and mucous membranes of the mouth and pharynx. Special visceral afferent sensory fibers transmit information from the taste buds of the posterior third of the tongue. Information from the carotid sinus and body that helps control blood pressure, pulse, and respiration is carried via the carotid sinus nerve, which is a branch of the glossopharyngeal nerve. Parasympathetic fibers pass via the glossopharyngeal nerve to the otic ganglion. Postganglionic fibers from the ganglion carry secretory information to the parotid gland. The glossopharyngeal nerve exits from the jugular foramen in proximity to the vagus and accessory nerves and the internal jugular vein (Fig. 26-2). All three nerves lie in the groove between the internal jugular vein and internal carotid artery. The key landmark for extraoral glossopharyngeal nerve block is the styloid process of the temporal bone. This osseous process represents the calcification of the cephalad end of the stylohyoid ligament. Although usually easy to identify, the styloid process may be difficult to locate with the exploring needle if ossification is limited.

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ABSTRACT

KEY WORDS

The glossopharyngeal nerve exits from the jugular foramen in proximity to the vagus and accessory nerves and the internal jugular vein. The glossopharyngeal nerve contains both motor and sensory fibers. The motor fibers innervate the stylopharyngeus muscle. The sensory portion of the nerve innervates the posterior third of the tongue, palatine tonsil, and mucous membranes of the mouth and pharynx. Special visceral afferent sensory fibers transmit information from the taste buds of the posterior third of the tongue. Information from the carotid sinus and body that helps control blood pressure, pulse, and respiration is carried via the carotid sinus nerve, which is a branch of the glossopharyngeal nerve. Parasympathetic fibers pass via the glossopharyngeal nerve to the otic ganglion. Postganglionic fibers from the ganglion carry secretory information to the parotid gland. Destruction of the glossopharyngeal nerve is indicated for the palliation of cancer pain, including pain secondary to invasive tumors of the posterior tongue, hypopharynx, and tonsils.

cancer pain glossopharyngeal nerve glossopharyngeal nerve block glossopharyngeal neuralgia

microvascular decompression radiofrequency destruction radiofrequency lesioning

A

B

C

D

E

F

G

H

I

J

K

Figure 26-1 A, T1 hypopharynx cancer arising from the lateral wall of the pyriform sinus on the right, which is exophytic, small volume, and has normal vocal cord mobility. B, Pretreatment computed tomographic (CT) image of the pyriform sinus cancer in A. C, Pretreatment positron emission tomography–CT image of the pyriform sinus cancer in A. D, Exophytic T2 hypopharynx cancer arising from the pyriform sinus and involving the arytenoid and aryepiglottic fold on the left with normal vocal cord mobility. E, F, and G, Pretreatment CT images of the T2 hypopharynx cancer shown in D. H, Exophytic T2 hypopharynx cancer arising from the pyriform sinus and involving the arytenoid and aryepiglottic fold on the left with normal vocal cord mobility. I and J, Pretreatment CT images of the T2 hypopharynx cancer shown in H. K, Location of hypopharynx cancer in H with no evidence of disease 5 years after radiotherapy. (From Foote RL: Radiotherapy alone for early-stage squamous cell carcinoma of the larynx and hypopharynx. Int J Radiat Oncol Biol Phys 69[2 suppl]:S31-S36, 2007.)

Styloid process Mastoid Glossopharyngeal nerve Internal jugular vein

Figure 26-2 The glossopharyngeal nerve exits from the jugular foramen in proximity to the vagus and accessory nerves and the internal jugular vein. All three nerves lie in the groove between the internal jugular vein and internal carotid artery.

Accessory nerve Hypoglossal n. Vagus nerve

Internal carotid artery

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Styloid process

Mastoid Styloid process Mandibular angle

Figure 26-3 An imaginary line is visualized running from the mastoid process to the angle of the mandible The styloid process should lie just below the midpoint of this line.

TECHNIQUE Landmark and Fluoroscopically Guided Technique The patient is placed in the supine position. An imaginary line is visualized running from the mastoid process to the angle of the mandible (Fig. 26-3). The styloid process should lie just below the midpoint of this line. The skin

Figure 26-5 process.

Radiofrequency needle tip resting against the styloid

is prepared with antiseptic solution, and local anesthetic is injected into the skin and subcutaneous tissues at the intended site of needle entry. A 20-gauge, 10-cm blunt curved radiofrequency needle with a 10-mm active tip is placed via a 16-gauge introducer needle through the previously anesthetized area until the tip rests against the styloid process (Figs. 26-4 and 26-5). The styloid process should be encountered within 3 cm. After contact is

Styloid process

Glossopharyngeal nerve

Figure 26-4 A 20-gauge, 10-cm blunt curved radiofrequency needle with a 10-mm active tip is placed via a 16-gauge introducer needle through the previously anesthetized area until the tip rests against the styloid process. After contact is made, the needle is withdrawn and walked off the styloid process posteriorly.

26 GLOSSOPHARYNGEAL NERVE BLOCK: RADIOFREQUENCY LESIONING

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Styloid process

Figure 26-7

Proper transducer placement for ultrasound-guided glossopharyngeal nerve block via the extraoral approach.

Figure 26-6 Needle tip just behind the posterior aspect of the styloid process in proximity to the glossopharyngeal nerve. made, the needle is withdrawn and walked off the styloid process posteriorly (Fig. 26-6). As soon as bony contact is lost and careful aspiration reveals no blood or cerebrospinal fluid, a small amount of nonionic contrast medium can be injected to demonstrate proper needle position and confirm the absence of vascular runoff. Sensory stimulation of up to 1 V at 50 Hz should produce stimulation at the base of the tongue, pharynx, and ipsilateral tonsillar fossa. The patient should be carefully observed for stimulation-induced bradycardia or hypotension. Motor stimulation at 2 to 2.5 V at 2 Hz is then carried out to demonstrate the lack of stimulation of the muscles innervated by the phrenic and spinal accessory nerves. Then 2 mL of 1% lidocaine is injected, and after time is allowed for the drug to produce anesthesia, pulsed radiofrequency lesioning is carried out at a rate of 2 Hz with a pulse width of 20 milliseconds at a temperature of 42°C for a duration of 120 seconds. This sequence is repeated two or three times.

to malignancy. A high-frequency linear ultrasound transducer is then placed over the previously identified location of the styloid process and a sonogram is taken (Fig. 26-7). The styloid process, glossopharyngeal nerve, and adjacent carotid artery and jugular vein are identified (Fig. 26-8). A 20-gauge, 10-cm blunt curved radiofrequency needle with a 10-mm active tip is placed via a 16-gauge introducer needle through the previously anesthetized area and advanced under real-time ultrasound guidance toward the styloid process using an out-of-plane approach. The styloid process should be encountered within approximately 3 cm. After contact with the styloid process is made, the needle is withdrawn slightly out of the periosteum or substance of the calcified ligament and under real-time ultrasound guidance is walked off the posterior aspect of the styloid process/ligament and advanced slightly so the needle tip rests in proximity to the glossopharyngeal nerve. The glossopharyngeal nerve should be identifiable adjacent to the carotid artery (see

Glossopharyngeal nerve

Ultrasound-Guided Technique The patient is placed in the supine position with the head turned away from the side to be blocked. An imaginary line is visualized running from the mastoid process to the angle of the mandible (see Fig. 26-3). The styloid process should lie just below the midpoint of this line. The skin is prepared with antiseptic solution. A total of 5 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for pain in areas subserved by the glossopharyngeal nerve that is thought to have an inflammatory basis, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. Neurolytic blocks using small amounts of 6.5% aqueous phenol can be performed for intractable pain secondary

Jugular vein

Carotid a.

Mastoid process

Styloid process

Figure 26-8

Ultrasound image demonstrating the relationship of the glossopharyngeal nerve to the styloid process, carotid artery, and jugular vein. a., Artery.

Fig. 26-8). After careful aspiration reveals no blood or cerebrospinal fluid, 3 mL of solution is slowly injected. The needle is removed and pressure is placed on the injection site to avoid bleeding complications. Subsequent daily nerve blocks are carried out in a similar manner.

SIDE EFFECTS AND COMPLICATIONS The major complications associated with radiofrequency lesioning of the glossopharyngeal nerve are related to trauma to the internal jugular vein and carotid artery. Hematoma formation and intravascular injection of local anesthetic with subsequent toxicity are not uncommon complications of glossopharyngeal nerve block. The patient should be informed that blockade of the motor portion of the glossopharyngeal nerve can result in dysphagia secondary to weakness of the stylopharyngeus muscle. If the vagus nerve is inadvertently blocked, as is often the case during glossopharyngeal nerve block,

dysphonia secondary to paralysis of the ipsilateral vocal cord may occur. A reflex tachycardia secondary to vagal nerve block also is observed in some patients. Inadvertent block of the hypoglossal and spinal accessory nerves during glossopharyngeal nerve block results in weakness of the tongue and trapezius muscle. A small percentage of patients who undergo chemical neurolysis or neurodestructive procedures of the glossopharyngeal nerve experience postprocedure dysesthesias in the area of anesthesia. These symptoms range from a mildly uncomfortable burning or pulling sensation to severe pain. When this severe postprocedure pain occurs, it is called anesthesia dolorosa. Anesthesia dolorosa can be worse than the patient’s original pain complaint and is often harder to treat. Although uncommon, infection remains an ever-present possibility, especially in the immunocompromised cancer patient. Early detection of infection is crucial to avoid potentially life-threatening sequelae.

Clinical Pearls Glossopharyngeal nerve block is a simple technique that can produce dramatic relief for patients suffering from the previously mentioned pain complaints. Neurolytic block with small quantities of alcohol, phenol, and glycerol has been shown to provide long-term relief for patients with glossopharyngeal neuralgia and cancer-related pain who have shown no response to more conservative treatments. Destruction of the glossopharyngeal nerve can also be carried out by creating a radiofrequency lesion under biplanar fluoroscopic guidance. Stimulation during radiofrequency lesioning of the glossopharyngeal nerve can induce bradycardia and hypotension in some patients.

As mentioned earlier, the proximity of the glossopharyngeal nerve to major vasculature makes postblock hematoma and ecchymosis a distinct possibility. Although these complications are usually transitory, their dramatic appearance can be quite upsetting to the patient, and therefore the patient should be warned of this possibility before the procedure. The vascularity of this region also increases the incidence of inadvertent intravascular injection. Even small amounts of local anesthetic injected into the carotid artery at this level will result in local anesthetic toxicity and seizures. Incremental dosing while the patient is carefully monitored for signs of local anesthetic toxicity helps avoid this complication.

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Vagus Nerve Block INDICATIONS

CPT-2015 Code Unilateral Neurolytic

64408 64640

Relative Value Units Unilateral Neurolytic

12 20

Vagus nerve block with local anesthetic can be used as a diagnostic tool when performing differential neural blockade on an anatomic basis in the evaluation of head and facial pain. If destruction of the vagus nerve is being considered, this technique can be used in a prognostic manner to indicate the degree of motor and sensory impairment that the patient may experience. Vagus nerve block with local anesthetic may be used for palliation in acute pain

27

ABSTRACT

KEY WORDS

The vagus nerve exits from the jugular foramen in close proximity to the spinal accessory nerve. The vagus nerve lies just caudad to the glossopharyngeal nerve and is superficial to the internal jugular vein. The vagus nerve courses downward from the jugular foramen within the carotid sheath along with the internal jugular vein and internal carotid artery. The vagus nerve contains both motor and sensory fibers. The motor fibers innervate the pharyngeal muscle and provide fibers for the superior and recurrent laryngeal nerves. The sensory portion of the nerve innervates the dura mater of the posterior fossa, the posterior aspect of the external auditory meatus, the inferior aspect of the tympanic membrane, and the mucosa of the larynx below the vocal cords. The vagus nerve also provides fibers to the intrathoracic contents, including the heart, lungs, and major vasculature. Vagus nerve block can be used as a diagnostic, prognostic, or therapeutic maneuver. Vagus nerve stimulation has shown promise in the treatment of intractable seizures.

intractable seizures jugular foramen seizures spinal accessory nerve

VAGUS NERVE BLOCK

98.e1

vagus nerve vagus nerve block vagus nerve stimulation

27

VAGUS NERVE BLOCK

99

emergencies, including vagal neuralgia and cancer pain, during the wait for pharmacologic, surgical, and antiblastic methods to take effect. Vagus nerve block is used as a diagnostic and therapeutic maneuver in those patients suspected of having vagal neuralgia. Destruction of the vagus nerve is indicated for the palliation of cancer pain, including pain secondary to invasive tumors of the larynx, hypopharynx, and pyriform sinus and occasionally intrathoracic malignancies (Fig. 27-1). Because of the desperate condition of many patients who have aggressively invasive head and neck malignancies, blockade of the vagus nerve using a 25-gauge needle may be carried out in the presence of coagulopathy or anticoagulation, albeit with an increased risk of ecchymosis and hematoma formation.

The vagus nerve exits from the jugular foramen in close proximity to the spinal accessory nerve (Fig. 27-2). The vagus nerve lies just caudad to the glossopharyngeal nerve and is superficial to the internal jugular vein. The vagus nerve courses downward from the jugular foramen within the carotid sheath along with the internal jugular vein and internal carotid artery. Blockade of the vagus nerve is carried out in a manner analogous to glossopharyngeal nerve block. The key landmark for vagus nerve block is the styloid process of the temporal bone. This osseous process represents the calcification of the cephalad end of the stylohyoid ligament. Although usually easy to identify, the styloid process may be difficult to locate with the exploring needle if ossification is limited.

CLINICALLY RELEVANT ANATOMY

TECHNIQUE

The vagus nerve contains both motor and sensory fibers. The motor fibers innervate the pharyngeal muscle and provide fibers for the superior and recurrent laryngeal nerves. The sensory portion of the nerve innervates the dura mater of the posterior fossa, the posterior aspect of the external auditory meatus, the inferior aspect of the tympanic membrane, and the mucosa of the larynx below the vocal cords. The vagus nerve also provides fibers to the intrathoracic contents, including the heart, lungs, and major vasculature.

Landmark and Fluoroscopically Guided Technique The patient is placed in the supine position. An imaginary line is visualized running from the mastoid process to the angle of the mandible (Fig. 27-3). The styloid process should lie just below the midpoint of this line. The skin is prepared with antiseptic solution. A 22-gauge, 1 1 2-inch needle attached to a 10-mL syringe is advanced at this midpoint location in a plane perpendicular to the skin. The styloid process should be encountered within 3 cm (Fig. 27-4). After contact is made, the needle is withdrawn

A

B Figure 27-1

A, Exophytic tumor originating from the pyriform sinus was observed in the preoperative endoscopy. The pyriform sinus was obliterated. B, Protruding tumor was observed in the posterior pharyngeal wall. Repeat endoscopy 6 months later. (From Park YM, Kim WS, De Virgilio A, et al: Transoral robotic surgery for hypopharyngeal squamous cell carcinoma: 3-year oncologic and functional analysis. Oral Oncol 48[6]:560566, 2012.)

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Styloid process Mastoid

Glossopharyngeal nerve Accessory nerve Internal jugular vein

Hypoglossal n. Vagus nerve

Internal carotid artery

and walked off the styloid process posteriorly and in a slightly inferior trajectory. The needle is advanced about 0.5 cm past the depth at which the styloid process was identified. If careful aspiration reveals no blood or cerebrospinal fluid, 5 mL of 0.5% preservative-free lidocaine combined with 80 mg of methylprednisolone is injected in incremental doses. Subsequent daily nerve blocks are

Mastoid Styloid process Mandibular angle

Figure 27-3 An imaginary line is visualized running from the mastoid process to the angle of the mandible. The styloid process should lie just below the midpoint of this line.

Figure 27-2

nerve.

Anatomy of the vagus

carried out in a similar manner, with 40 mg of methylprednisolone substituted for the initial 80-mg dose. This approach also may be used to treat breakthrough pain in patients who previously experienced adequate pain control with oral medications.

Ultrasound-Guided Technique The patient is placed in the supine position with the head turned away from the side to be blocked. An imaginary line is visualized running from the mastoid process to the angle of the mandible. The styloid process should lie just below the midpoint of this line (Fig. 27-5). The skin is prepared with antiseptic solution. A total of 5 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for pain in areas subserved by the glossopharyngeal nerve that is thought to have an inflammatory basis, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depotsteroid is added with subsequent blocks. Neurolytic blocks using small amounts of 6.5% aqueous phenol can be performed for intractable pain secondary to malignancy. A high-frequency linear ultrasound transducer is then placed over the previously identified location of the styloid process and a sonogram is taken (Fig. 27-6). The styloid process, vagus nerve, and adjacent carotid artery and jugular vein are identified (Fig. 27-7). Color Doppler imaging can be used to help identify the carotid artery and jugular vein (Fig. 27-8). A 22-gauge, 3 1 2-inch styletted spinal needle is then advanced under real-time ultrasound guidance toward the styloid process using an out-of-plane approach. The styloid process should be encountered within approximately 3 cm. After contact with the styloid process is made, the needle is withdrawn slightly out of the periosteum or substance of the calcified ligament and

27

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101

Styloid process Mastoid Glossopharyngeal nerve

Accessory nerve Hypoglossal n. Internal jugular vein

Vagus nerve

Internal carotid artery

Figure 27-4

After contact with the styloid process is made, the needle is withdrawn and walked off the styloid process posteriorly and in a slightly inferior trajectory.

Figure 27-6 Proper transducer placement and needle trajectory for ultrasound-guided vagus nerve block.

Figure 27-5 Needle tip just behind the posterior aspect of the styloid process in proximity to the vagus nerve.

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Vagus nerve Styloid process

Jugular vein

Carotid artery

Figure 27-7

Ultrasound image demonstrating the vagus nerve and adjacent jugular vein and carotid artery.

The needle is removed and pressure is placed on the injection site to avoid bleeding complications. Subsequent daily nerve blocks are carried out in a similar manner.

SIDE EFFECTS AND COMPLICATIONS

under real-time ultrasound guidance is walked off the posterior aspect of the styloid process/ligament in a posterior and slightly inferior trajectory and advanced slightly so the needle tip rests in proximity to the vagus nerve (see Fig. 27-4). After careful aspiration reveals no blood or cerebrospinal fluid, 3 mL of solution is slowly injected.

The major complications associated with vagus nerve block are related to trauma to the internal jugular vein and carotid artery. Hematoma formation and intravascular injection of local anesthetic with subsequent toxicity are not uncommon after vagus nerve block. Blockade of the motor portion of the vagus nerve can result in dysphonia and difficulty coughing due to blockade of the superior and recurrent laryngeal nerves. A reflex tachycardia secondary to vagal nerve block is also observed in some patients. Inadvertent block of the glossopharyngeal, hypoglossal, and spinal accessory nerves during vagus nerve block will result in weakness of the tongue and trapezius muscle and numbness in the distribution of the glossopharyngeal nerve. Although uncommon, infection remains an everpresent possibility, especially in the immunocompromised cancer patient. Early detection of infection is crucial to avoid potentially life-threatening sequelae.

Figure 27-9

Figure 27-10

Carotid artery

Jugular vein

Figure 27-8

Color Doppler imaging can be used to help identify the carotid artery and jugular vein.

Exposure of the vagus nerve (white arrow) between the internal jugular vein laterally (blue arrow) and the common carotid artery medially (red arrow). (From Roux FX, Turak B, Landré E: Stimulation chronique du nerf vague dans le traitement del’épilepsie pharmacorésistante. Neurochirurgie 54[3]:332-339, 2008.)

Two electrodes and a stabilizing coil wrapped around the vagus nerve. The lead forms a strain-relief loop held in place by two white silicone tie-downs sutured to the sides. (From Roux FX, Turak B, Landré E: Stimulation chronique du nerf vague dans le traitement del’épilepsie pharmacorésistante. Neurochirurgie 54[3]:332-339, 2008.)

Clinical Pearls Vagus nerve block should be considered in two clinical situations: (1) in patients with vagal neuralgia, and (2) in patients with cancer in the previously mentioned areas who experience persistent ill-defined pain that fails to respond to conservative measures. Vagal neuralgia is clinically analogous to trigeminal and glossopharyngeal neuralgia. It is characterized by paroxysms of shocklike pain into the thyroid and laryngeal areas. Pain may occasionally radiate into the jaw and upper thoracic region. Attacks of vagal neuralgia may be precipitated by coughing, yawning, and swallowing. Excessive salivation also may be present. This is a rare pain syndrome and should be considered a diagnosis of exclusion. Neurolytic block with small quantities of alcohol, phenol, and glycerol has been shown to provide long-term relief for patients with vagus neuralgia and cancer-related pain who have shown no response to more conservative treatments. Destruction of the vagus nerve can be also carried out by creating a radiofrequency lesion under biplanar fluoroscopic guidance.

As mentioned earlier, the proximity of the vagus nerve to major vasculature makes postblock hematoma and ecchymosis a distinct possibility. Although these complications are usually transitory, their dramatic appearance can be quite upsetting to the patient, and therefore the patient should be warned of this possibility before the procedure. The vascularity of this region also increases the incidence of inadvertent intravascular injection. Even small amounts of local anesthetic injected into the carotid artery at this level will result in local anesthetic toxicity and seizures. Incremental dosing while the patient is carefully monitored for signs of local anesthetic toxicity helps avoid this complication. The use of vagal nerve stimulation to treat intractable epileptic seizures has gained increasing acceptance as the technology has improved. To perform vagus nerve stimulation, the vagus nerve is identified and stimulation leads are placed around the nerve and attached to a implantable pulse generator (Figs. 27-9 and 27-10). Cardiac arrhythmias are a not uncommon side effect of this promising new treatment modality (Fig. E27-1).

27

VAGUS NERVE BLOCK

103.e1

Figure E27-1 Asystole during vagal nerve stimulation. (From Shankar R, Olotu VO, Cole N, et al: Case report: vagal nerve stimulation and late onset asystole. Seizure 22[4]:312-314, 2013.)

28

SPINAL ACCESSORY NERVE BLOCK

C H A P T E R

103

28

Spinal Accessory Nerve Block CPT-2015 Code Unilateral Neurolytic

64412 64640

may be carried out by chemoneurolysis, cryoneurolysis, radiofrequency lesioning, surgical crushing, or resection of the nerve.

CLINICALLY RELEVANT ANATOMY Relative Value Units Unilateral Neurolytic

12 20

INDICATIONS Spinal accessory nerve block is useful in the diagnosis and treatment of spasm of the sternocleidomastoid or trapezius muscle. It is also occasionally useful as a diagnostic maneuver to determine whether spasm of these muscles is being mediated by the spinal accessory nerve. Spinal accessory nerve block with local anesthetic is also used in a prognostic manner before destruction of the spinal accessory nerve for the palliation of spastic conditions of the sternocleidomastoid or trapezius muscle including spasmodic torticollis and the cervical dystonias (Fig. 28-1). Neurodestruction of the spinal accessory nerve

The spinal accessory nerve arises from the nucleus ambiguus. The nerve has two roots, which leave the cranium together, along with the vagus nerve, via the jugular foramen (Fig. 28-2). The fibers of the spinal root pass inferiorly and posteriorly to provide motor innervation to the superior portion of the sternocleidomastoid muscle. The spinal accessory nerve exits the posterior border of the sternocleidomastoid muscle in the upper third of the muscle (Figs. 28-3 and E28-1). The nerve, in combination with the cervical plexus, provides innervation to the trapezius muscle.

TECHNIQUE Landmark Technique The patient is placed in a supine position with the head turned away from the side to be blocked. A total of 10 mL of local anesthetic is drawn up in a 20-mL sterile

103.e2

SECTION II

NECK

ABSTRACT

KEY WORDS

The spinal accessory nerve (cranial nerve XI) is also known as the accessory nerve. It has two roots, which leave the cranium together, along with the vagus nerve, via the jugular foramen. The fibers of the spinal root pass inferiorly and posteriorly to provide motor innervation to the superior portion of the sternocleidomastoid muscle. The spinal accessory nerve exits the posterior border of the sternocleidomastoid muscle in the upper third of the muscle. The nerve, in combination with the cervical plexus, provides innervation to the trapezius muscle. Spinal accessory nerve block is useful in the diagnosis and treatment of spasm of the sternocleidomastoid or trapezius muscle.

cervical dystonias spasmodic torticollis spinal accessory nerve spinal accessory nerve block

sternocleidomastoid muscle trapezius muscle ultrasound-guided spinal accessory nerve block

TM

LSM

A

LSM

B Figure E28-1

LSM

C

Axial ultrasound slice of the right spinal accessory nerve (white arrow) in a volunteer (A) and comparative gross anatomic (B) and histologic (C) slices in a cadaver in the posterior triangle of the neck superficial to the levator scapulae muscle (LSM). TM, Trapezius muscle. (From Canella C, Demondion X, Abreu E, et al: Anatomical study of spinal accessory nerve using ultrasonography. Eur J Radiol 82[1]:56-61, 2013.)

104

SECTION II

NECK

A

B

Figure 28-1 Patient affected by cervical dystonia (rotational type). Note the hypertrophy of the sternocleidomastoid muscle contralateral to the head rotation (A) and a typical sensory trick (B). (From Colosimo C, Berardelli A: Clinical phenomenology of dystonia. Int Rev Neurobiol 98:509524, 2011.)

syringe. When the treatment is for conditions mediated by the spinal accessory nerve that are thought to have an inflammatory component, a total of 80 mg of depotsteroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The patient is asked to raise his or her head against the resistance of the pain management specialist’s hand to aid in identification of the posterior border of the sternocleidomastoid muscle. The posterior border of the upper third of the muscle is then identified. At a point

just behind the posterior border of the upper third of the sternocleidomastoid muscle, after preparation of the skin with antiseptic solution, a 1 1 2-inch needle is inserted with a slightly anterior trajectory (Fig. 28-4). After the needle is inserted to a depth of about 3 4 inch, gentle aspiration is carried out to identify blood or cerebrospinal fluid. If the aspiration results are negative and no paresthesia into the brachial plexus is elicited, 10 mL of solution is slowly injected in a fanlike manner, with close monitoring of the patient for signs of local anesthetic toxicity or inadvertent subarachnoid injection.

Sternocleidomastoid

Spinal accessory nerve Levator scapulae muscle

Trapezius

Figure 28-2 Anatomy of the spinal accessory nerve. (From Long TR, Wass CT, Burkle CM: Perioperative interscalene blockade: an overview of its history and current clinical use. J Clin Anesth 14[7]:546-556, 2002.)

28 POSTERIOR

SPINAL ACCESSORY NERVE BLOCK

105

ANTERIOR

SCM

Figure 28-5 TM

The posterior border of the sternocleidomastoid muscle is identified by having the patient raise his or her head against the resistance of the clinician’s hand.

Ultrasound-Guided Technique

Figure 28-3

Right dissected specimen shows the spinal accessory nerve (white arrow) lying on the fat tissue that covers the levator scapulae muscle on the cervical posterior triangle (dotted white line). The spinal accessory nerve is observed between the sternocleidomastoid muscle (SCM) and the trapezius muscle (TM). (From Canella C, Demondion X, Abreu E, et al: Anatomical study of spinal accessory nerve using ultrasonography. Eur J Radiol 82[1]:56-61, 2013.)

The patient is placed in the supine position with the head turned away from the side to be blocked. The posterior border of the sternocleidomastoid muscle is identified by having the patient raise his or her head against the resistance of the clinician’s hand (Fig. 28-5). The junction of the upper and middle third of the posterior margin of the muscle is identified, which is the approximate point at which the spinal accessory nerve emerges from behind the sternocleidomastoid muscle and is most easily identified on ultrasound imaging. After preliminary identification

Sternocleidomastoid m.

Spinal accessory nerve Trapezius m.

Figure 28-4 Proper needle trajectory for spinal accessory nerve block. m., Muscle.

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complications. Subsequent daily nerve blocks are carried out in a similar manner.

SIDE EFFECTS AND COMPLICATIONS

Figure 28-6

Proper placement of the high-frequency linear ultrasound transducer and proper needle trajectory for ultrasound-guided spinal accessory nerve block.

of the approximate location of the nerve is made using surface landmarks, the skin is prepared with antiseptic solution and 2 mL of local anesthetic is drawn up in a 10-mL sterile syringe, with 40 to 80 mg of depot-steroid added if the condition being treated is thought to have an inflammatory component. A linear ultrasound transducer is then placed over the approximate location of the nerve as identified previously, in the transverse plane (Fig. 28-6). The spinal accessory nerve should appear as a 2- to 3-mm hypoechoic oval structure with a hyperechoic perineurium lying on top of the levator scapulae muscle as it exits beneath the posterior margin of the sternocleidomastoid muscle (Fig. 28-7). Its course can be traced in a posterior and caudad direction toward the anterior margin of the trapezius muscle. When the nerve is identified, a 22-gauge, 2-inch stimulating needle is advanced under real-time ultrasound guidance using an in-plane approach (see Fig. 28-6). When the needle tip is in proximity to the nerve, stimulation is carried out, with isolated contraction of the trapezius muscle indicating satisfactory needle placement. After careful aspiration reveals no blood or cerebrospinal fluid, 2 mL of solution is slowly injected. The needle is removed and pressure is placed on the injection site to avoid bleeding

The proximity to the external jugular vein and other large vessels suggests the potential for inadvertent intravascular injection or local anesthetic toxicity from intravascular absorption. The pain management specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely. This vascularity also gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can safely be performed in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable riskto-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20 minutes on, 20 minutes off, after the block also decreases the amount of postprocedure pain and bleeding the patient may experience. Not only is there the potential for complications involving the vasculature, but the proximity of the spinal accessory nerve to the central neuraxial structures and the phrenic nerve also can result in side effects and complications. If the needle is placed too deep, inadvertent epidural, subdural, or subarachnoid injection is a possibility. If the volume of local anesthetic used for the block is accidentally placed in any of these spaces, significant motor and sensory block will result. Unrecognized, these complications could be fatal. Blockade of the phrenic nerve may occur during blockade of the spinal accessory nerve. In the absence of significant pulmonary disease, unilateral phrenic nerve block should rarely create respiratory embarrassment. However, blockade of the recurrent laryngeal nerve with its attendant vocal cord paralysis, combined with paralysis of the diaphragm, may make the clearing of pulmonary and upper airway secretions difficult. Additionally, blockade of the vagus and glossopharyngeal nerves also may occur when spinal accessory nerve block is performed.

Spinal accessory nerve

Levator scapulae muscle

Figure 28-7

Ultrasound image of the spinal accessory nerve. Note the relationship to the levator scapulae muscle.

Clinical Pearls A clear diagnosis of the cause of spastic conditions of the cervical musculature should be ascertained before spinal accessory nerve block. Demyelinating disease, the cervical dystonias (including spasmodic torticollis), and posterior fossa and brain stem tumors must be ruled out. The workup should include magnetic resonance imaging of the head, with special attention to the posterior fossa and brain stem, as well as electromyography and, if indicated, measurement of trimodal

evoked potentials. Laboratory testing for the inflammatory myopathies and the collagen vascular diseases should be considered as the clinical situation dictates. For treatment of spasticity of the cervical musculature, botulinum toxin administered under electromyographic guidance may allow better control of the amount of muscle weakness produced than do neurodestructive procedures of the spinal accessory nerve.

29

PHRENIC NERVE BLOCK

C H A P T E R

107

29

Phrenic Nerve Block CPT-2015 Code Unilateral Neurolytic

64410 64640

Relative Value Units Unilateral Neurolytic

12 20

the anterior scalene muscle (Figs. 29-2 and 29-3). The phrenic nerve passes inferiorly between the omohyoid and sternocleidomastoid muscles and exits the root of the neck between the subclavian artery and vein to enter the mediastinum. The right phrenic nerve follows the course of the vena cava to provide motor innervation to the right hemidiaphragm. The left phrenic nerve descends to provide motor innervation to the left hemidiaphragm in a course parallel to that of the vagus nerve.

INDICATIONS Phrenic nerve block is useful in the diagnosis and treatment of intractable hiccups. It is also occasionally useful as both a diagnostic and therapeutic maneuver to determine whether pain from subdiaphragmatic processes, including abscess and malignancy, is being mediated via the phrenic nerve (Fig. 29-1). Phrenic nerve block with local anesthetic is also used in a prognostic manner before destruction of the phrenic nerve for palliation of intractable hiccups. Neurodestruction of the phrenic nerve may be carried out by chemoneurolysis, cryoneurolysis, radiofrequency lesioning, surgical crushing, or resection of the nerve.

CLINICALLY RELEVANT ANATOMY The phrenic nerve arises from fibers of the primary ventral ramus of the fourth cervical nerve, with contributions from the third and fifth cervical nerves. The phrenic nerve descends in proximity to the internal jugular vein across

Figure 29-1

Schwannoma of the phrenic nerve. Yellow to brown cut surface with area of calcification in the middle and an attached piece of phrenic nerve at the periphery. (From Gilani SM, Danforth RD: Intractable hiccups: a rare presentation of phrenic nerve schwannoma. Eur Ann Otorhinolaryngol Head Neck Dis 129[6]:331-333, 2012.)

29

ABSTRACT

KEY WORDS

The phrenic nerve arises from fibers of the primary ventral ramus of the fourth cervical nerve, with contributions from the third and fifth cervical nerves. The phrenic nerve passes inferiorly between the omohyoid and sternocleidomastoid muscles and exits the root of the neck between the subclavian artery and vein to enter the mediastinum. The right phrenic nerve follows the course of the vena cava to provide motor innervation to the right hemidiaphragm. The left phrenic nerve descends to provide motor innervation to the left hemidiaphragm in a course parallel to that of the vagus nerve. Phrenic nerve block is useful in the diagnosis and treatment of intractable hiccups. It is also occasionally useful as both a diagnostic and therapeutic maneuver to determine whether pain from subdiaphragmatic processes, including abscess and malignancy, is being mediated via the phrenic nerve. Phrenic nerve block with local anesthetic is also used in a prognostic manner before destruction of the phrenic nerve for palliation of intractable hiccups.

hiccups intractable hiccups phrenic nerve phrenic nerve block

PHRENIC NERVE BLOCK

107.e1

radiofrequency lesioning singultus subdiaphragmatic abscess

108

SECTION II

NECK

The Scalene Triangle

Middle scalene m.

Anterior scalene m.

Phrenic n. Subclavian artery Long thoracic n.

Subclavian vein

First rib

Figure 29-2 Anatomy of the phrenic nerve. Note the relationship of the phrenic nerve to the anterior scalene muscle. m., Muscle; n., nerve. (From Thompson RW, Driskill M: Neurovascular problems in the athlete’s shoulder. Clin Sports Med 27[4]:789-802, 2008.)

TECHNIQUE Landmark Technique The patient is placed in a supine position with the head turned away from the side to be blocked. A total of 10 mL of local anesthetic is drawn up in a 20-mL sterile syringe. When the treatment is for painful conditions involving the phrenic nerve that are associated with inflammation, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks.

Figure 29-4 To aid in identification of the posterior border of the sternocleidomastoid muscle, the patient is asked to raise his or her head against the resistance of the pain management specialist’s hand. The patient is then asked to raise his or her head against the resistance of the pain management specialist’s hand to aid in identification of the posterior border of the sternocleidomastoid muscle (Fig. 29-4). In most patients, a groove between the posterior border of the sternocleidomastoid muscle and the anterior scalene muscle can be palpated. At a point 1 inch above the clavicle, at this groove or just slightly behind the posterior border of the sternocleidomastoid muscle, and after preparation of the skin with antiseptic solution, a 11 2-inch needle is inserted with a slightly anterior trajectory (Fig. 29-5). After the needle is inserted to a depth of about 1 inch, gentle aspiration is carried out to identify blood or cerebrospinal fluid. If the aspiration results are negative and no paresthesia into the brachial plexus is elicited, 10 mL of solution is slowly injected in a fanlike manner, with close monitoring of the patient for signs of local anesthetic toxicity or inadvertent subarachnoid injection.

Ultrasound-Guided Technique

Phrenic nerve Anterior scalene muscle

Brachial plexus

Figure 29-3

Middle scalene muscle

The phrenic nerve is seen over the anterior scalene muscle adjacent to the brachial plexus. Methylene blue dye surrounds the nerve. (From Kessler J, Schafhalter-Zoppoth I, Gray AT: An ultrasound study of the phrenic nerve in the posterior cervical triangle: implications for the interscalene brachial plexus block. Reg Anesth Pain Med 33[6]:545-550, 2008.)

The patient is placed in a supine position with the head turned away from the side to be blocked. A total of 10 mL of local anesthetic is drawn up in a 20-mL sterile syringe. When the treatment is for painful conditions involving the phrenic nerve that are associated with inflammation, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The patient is then asked to raise his or her head against the resistance of the pain management specialist’s hand to aid in identification of the posterior border of the sternocleidomastoid muscle (see Fig. 29-4). In most patients, a groove between the posterior border of the sternocleidomastoid muscle and the anterior scalene muscle can be palpated. The junction of the middle and lower middle third of the posterior margin of the muscle is identified, which is the approximate point at which the phrenic nerve emerges from beneath the sternocleidomastoid muscle, lying on top of the anterior scalene muscle where it is easily identified on ultrasound imaging. The skin is prepared with antiseptic solution, and a

29

PHRENIC NERVE BLOCK

109

Sternocleidomastoid m.

Ant. scalene m. Phrenic nerve

Clavicle

Omohyoid m.

Figure 29-5

Proper needle trajectory for the landmark approach to phrenic nerve block. Ant., Anterior; m., muscle.

high-frequency linear ultrasound transducer is then placed over the previously identified location of the nerve in the transverse plane (Fig. 29-6). The phrenic nerve should appear as a 2- to 3-mm hypoechoic oval monofascicular structure with a hyperechoic perineurium lying on top of the anterior scalene muscle as it exits beneath the posterior margin of the sternocleidomastoid muscle (Fig. 29-7). When the phrenic nerve is identified, a 22-gauge, 31 2-inch styletted needle is advanced under real-time ultrasound guidance using an in-plane approach

Figure 29-6 Proper transducer placement and needle trajectory for ultrasound-guided phrenic nerve block.

until the needle tip is in proximity to the nerve (see Fig. 29-6). After careful aspiration for blood or cerebrospinal fluid, 3 mL of solution is slowly injected. The needle is removed and pressure is placed on the injection site to avoid bleeding complications. Subsequent daily nerve blocks are carried out in a similar manner.

SIDE EFFECTS AND COMPLICATIONS The proximity to the external jugular vein and other large vessels suggests the potential for inadvertent intravascular injection or local anesthetic toxicity from intravascular absorption. The pain management specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely. This vascularity also gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can safely be performed in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable risk-to-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20 minutes on, 20 minutes off, after the block also decreases the amount of postprocedure pain and bleeding the patient may experience. Not only is there the potential for complications involving the vasculature, but the proximity of the phrenic nerve to the central neuraxial structures and the spinal accessory nerve also can result in side effects and complications. If

110

SECTION II

NECK

PN

Sternocleidomastoid muscle

C5 C6 Middle scalene muscle

Anterior scalene muscle C7

SCM ASM

A

B

Lateral

Figure 29-7 A, Sonogram of the interscalene groove in the neck obtained 1 cm caudal to the cricoid cartilage. B, Corresponding labeled image. The phrenic nerve (PN) is identified medial to the brachial plexus and superficial to the anterior scalene muscle (ASM), shown with approximate probe location in the inset. Large tick marks are spaced 10 mm apart. The borders of the sternocleidomastoid (SCM), anterior scalene, and middle scalene muscles are shown in red. (From Kessler J, Schafhalter-Zoppoth I, Gray AT: An ultrasound study of the phrenic nerve in the posterior cervical triangle: implications for the interscalene brachial plexus block. Reg Anesth Pain Med 33[6]:545-550, 2008.)

the needle is placed too deep, inadvertent epidural, subdural, or subarachnoid injection is a possibility. If the volume of local anesthetic used for this block is accidentally placed in any of these spaces, significant motor and sensory block will result. Unrecognized, these complications could be fatal. In the absence of significant

pulmonary disease, unilateral phrenic nerve block should rarely create respiratory embarrassment. However, blockade of the recurrent laryngeal nerve with its attendant vocal cord paralysis, combined with paralysis of the diaphragm, may make the clearing of pulmonary and upper airway secretions difficult.

C5 R1

C5

C6

ASM

R1

SA

A Figure 29-8

SA

B

SA

C

Inoperable superior sulcus tumor. A and B, Sagittal T1-weighted magnetic resonance images without (A) and with (B) intravenous gadolinium show the extension of the non–small cell lung tumor into the interscalene triangle. With intravenous gadolinium the nonenhancing nerve roots can be discerned from the enhancing tumor, and there is tumor up to the C5 nerve root. The subclavian artery (SA) is encased, and the tumor surrounds the anterior scalene muscle (ASM) and compresses the phrenic nerve. C, Note the relationship of the subclavian artery to C5. R1, First rib. (From van Es HW, Bollen TL, van Heesewijk HPM: MRI of the brachial plexus: a pictorial review. Eur J Radiol 74[2]:391-402, 2010.)

29

A

B

C

D

PHRENIC NERVE BLOCK

111

Figure 29-9

Classic skin signs of Waldenström’s macroglobulinemia. (From del Olmo A, España MA, Idoate C, et al: Macroglobulinemia de Waldenström asociada a lesiones cutáneas y crioglobulinemia tipo I. Actas Dermosifiliogr 99[2]:138-144, 2008.)

Box 29-1 Causes of Intractable Hiccups

Clinical Pearls

CENTRAL NERVOUS SYSTEM DISORDERS

Phrenic nerve block is useful in both the diagnosis and palliation of pain secondary to malignancies of the subdiaphragmatic region that produce ill-defined referred pain in the supraclavicular region. This referred pain is known as Kerr’s sign and generally does not respond to treatments focused on the primary subdiaphragmatic tumor. The use of phrenic nerve block for intractable hiccups can be of great value to patients with this distressing problem for whom pharmacologic management has failed. A cause should be determined for the intractable hiccups before destruction of the phrenic nerve (Box 29-1). The workup should include magnetic resonance imaging of the head, with special attention to the posterior fossa and brain stem, as well as a careful evaluation of the thoracic cavity and subdiaphragmatic region (Fig. 29-8). Additionally, the pain management specialist should be aware that there is a high incidence of intractable hiccups associated with the macroglobulinemias, and such a possibility should be considered, especially if the classic skin abnormalities associated with Waldenström’s macroglobulinemia are present (Fig. 29-9).

• Tumors, especially those involving the area of the tractus solitarius • Stroke • Meningitis • Encephalitis • Demyelinating disease • Traumatic brain injury DISORDERS OF THE PHRENIC AND VAGUS NERVES • • • • • • • • • •

Compression of the nerve by tumor Compression of the nerve by an aberrant blood vessel Compression of the nerve by an osteophyte Inflammation of the nerve Mediastinal tumors Abdominal tumors Hepatomegaly Ascites Gastroesophageal reflux Subdiaphragmatic abscess

SYSTEMIC DISEASES • • • • •

Waldenström’s macroglobulinemia Alcoholism Diabetes Electrolyte abnormalities Renal failure

DRUG EXPOSURE • • • •

Benzodiazepines Barbiturates Steroids Methyldopa

C H A P T E R

30

Facial Nerve Block CPT-2015 Code Unilateral Neurolytic

64402 64612

Relative Value Units Unilateral Neurolytic

12 20

INDICATIONS Facial nerve block is useful in the diagnosis and treatment of painful conditions and facial spasms in areas subserved by the facial nerve, including geniculate neuralgia, atypical facial neuralgias, the pain associated with Bell’s palsy, herpes zoster involving the geniculate ganglion (Ramsay Hunt syndrome), and spastic conditions such as hemifacial spasm (Figs. 30-1 and 30-2).

CLINICALLY RELEVANT ANATOMY The facial nerve provides both motor and sensory fibers to the head. The facial nerve arises from the brain stem at the inferior margin of the pons. The sensory portion of the facial nerve is called the nervus intermedius. As it leaves the pons, the nervus intermedius is susceptible to compression, producing a “trigeminal neuralgia–like” syndrome called geniculate neuralgia (Fig. 30-3). After leaving the pons, the fibers of the facial nerve travel across the subarachnoid space and enter the internal auditory meatus to pass through the petrous temporal

A

B

Figure 30-1

Classic Ramsay Hunt syndrome involving the patient’s left ear. (From Angles EM, Nelson SW, Higgins GL III: A woman with facial weakness: a classic case of Ramsay Hunt syndrome. J Emerg Med 44[1]:e137-e138, 2013.)

bone. The nerve then exits the base of the skull via the stylomastoid foramen. It passes downward and then turns forward to pass through the parotid gland, where it divides into fibers that provide innervation to the muscles of facial expression (Fig. 30-4).

TECHNIQUE Landmark and Fluoroscopically Guided Technique The patient is placed in a supine position with the head turned away from the side to be blocked to allow easy access to the mastoid process on the affected side. A total of 3 mL of local anesthetic is drawn up in a 12-mL sterile

C

D

Figure 30-2 Signs of hemifacial Bell’s palsy. A, Incomplete smile. B, Inability to close the right eye. C, Right eyebrow movement compromised. D, Incomplete right labial movement. (From Acyclovir for Bell’s palsy. Dent Abstr 54[3]:138-140, 2009.) 112

30

FACIAL NERVE BLOCK

113

Petrous bone

BA

L-VA XI-X-IX

VIII

R-VA

VII

Figure 30-5 Figure 30-3

Operative photo showing both vertebral arteries deviated to the left and the right vertebral artery (R-VA) compressing the facial nerve (VII). BA, Basilar artery; IX-X-XI, caudal cranial nerves; L-VA, left vertebral artery; VIII, vestibulocochlear nerve. (From Guan HX, Zhu J, Zhong J: Correlation between idiopathic hemifacial spasm and the MRI characteristics of the vertebral artery. J Clin Neurosci 18[4]: 528-530, 2011.)

syringe. When the treatment is for geniculate neuralgia, herpes zoster, or other painful conditions involving the facial nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The mastoid process on the affected side is then identified by palpation (Fig. 30-5). After preparation of the skin Temporal branches

Palpation of the mastoid process.

with antiseptic solution, a 22-gauge, 11 2-inch needle is inserted at the anterior border of the mastoid process immediately below the external auditory meatus and at the level of the middle of the ramus of the mandible. The needle is advanced perpendicularly until the needle approaches the periosteum of the underlying mastoid bone (Figs. 30-6 and 30-7). The needle is then redirected slightly more anteriorly until it slides past the anterior border of the mastoid. The needle is slowly advanced about 1 2 inch beyond the edge of the mastoid (Fig. 30-8). This places the needle in proximity to the point at which the facial nerve exits the stylomastoid foramen. After gentle aspiration for blood and cerebrospinal fluid, 3 to 4 mL of solution is injected in incremental doses.

Zygomatic branches

External acoustic meatus

Stylomastoid foramen Mastoid process

Facial nerve Styloid process Buccal branches

Cervical branch Marginal mandibular branch

Figure 30-4

Anatomy of the facial nerve.

114

SECTION II

NECK External acoustic meatus

Ramus of mandible

Stylomastoid foramen

Mastoid process

Styloid process Facial nerve

Figure 30-6

For facial nerve block, a 22-gauge, 1 1 2-inch needle is inserted at the anterior border of the mastoid process immediately below the external auditory meatus and at the level of the middle of the ramus of the mandible. The needle is then advanced perpendicularly until the needle approaches the periosteum of the underlying mastoid bone.

Ultrasound-Guided Technique The patient is placed in a supine position with the head turned away from the side to be blocked to allow easy access to the mastoid process on the affected side. A total of 3 mL of local anesthetic is drawn up in a 12-mL sterile syringe. When the treatment is for geniculate neuralgia, herpes zoster, or other painful conditions involving the

Figure 30-7

Needle tip resting against the mastoid process.

facial nerve, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The mastoid process on the affected side is then identified by palpation (see Fig. 30-5). After preparation of the skin with antiseptic solution, a high-frequency linear ultrasound transducer is placed in the transverse plane

Figure 30-8

Needle tip advanced just beyond the posterior aspect of the mastoid process.

30

FACIAL NERVE BLOCK

115

Mastoid process

Facial n. Stylomastoid foramen

Figure 30-9 Proper placement of the ultrasound transducer to perform ultrasound-guided facial nerve block. over the approximate location of the mastoid process as previously identified and a sonogram is taken (Fig. 30-9). The anteroinferior border of the mastoid bone is identified at a point just below the external auditory meatus (Fig. 30-10). The hyperechoic margin of the bone and its acoustic shadow should be easily identifiable. The facial nerve can then be identified as it exits the stylohyoid foramen (Fig. 30-11). Color Doppler imaging can be used to identify major blood vessels in proximity to the facial nerve (Fig. 30-12). A 22-gauge, 31 2-inch styletted spinal needle is then advanced under real-time ultrasound guidance to a point just in front of the anteroinferior border of the mastoid bone and advanced approximately 1 2 inch beyond the edge of the mastoid bone using an out-of-plane approach. After careful aspiration reveals no blood or cerebrospinal fluid, 3 mL of solution is slowly injected. The needle is removed and pressure is placed on the injection site to avoid bleeding complications. Subsequent daily nerve blocks are carried out in a similar manner.

Anterior

Posterior

Figurer 30-11

Transverse ultrasound image demonstrating the relationship of the facial nerve to the stylomastoid foramen and mastoid process. n., Nerve.

specialist should carefully observe the patient for signs of local anesthetic toxicity during injection. This vascularity and proximity to major blood vessels also give rise to an increased incidence of postblock ecchymosis and hematoma formation, and the patient should be warned of such. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation

SIDE EFFECTS AND COMPLICATIONS This anatomic region is highly vascular, and because of the proximity to major vessels, the pain management Jugular vein

Styloid shadow Carotid artery Mastoid process

Figure 30-10

Transverse ultrasound image of the mastoid process.

Figure 30-12 Color Doppler image demonstrating the relationship of the carotid artery and jugular vein to the styloid process.

116

SECTION II

NECK

indicates a favorable risk-to-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20 minutes on, 20 minutes off, after the block also decreases the amount of postprocedure pain and bleeding the patient may experience.

Because of the proximity to the spinal column, it is also possible to inadvertently inject the local anesthetic into the epidural, subdural, or subarachnoid space. At this level, even small amounts of local anesthetic placed into the subarachnoid space may result in total spinal anesthesia.

Clinical Pearls Facial nerve block is especially useful in the palliation of pain secondary to acute herpes zoster involving the geniculate ganglion (Ramsay Hunt syndrome). The addition of tepid aluminum acetate soaks helps dry weeping lesions and makes the patient more comfortable. Facial nerve block can provide palliation of the symptoms of hemifacial spasm. Facial nerve block is also useful in the management of geniculate neuralgia that has failed to respond to pharmacologic treatment. Geniculate neuralgia is a rare unilateral facial pain syndrome analogous

to trigeminal and glossopharyngeal neuralgia and is caused by compression of the facial nerve by aberrant arteries or tumors (see Fig. 30-3). It is characterized by paroxysms of shocklike pain deep in the ear that are triggered by talking and swallowing. Brain stem tumors involving the facial nerve may mimic this syndrome, and magnetic resonance imaging, with special attention to the posterior fossa and brain stem, and brain stem evoked response testing are indicated when the diagnosis of geniculate neuralgia is suspected.

116

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C H A P T E R

31

Superficial Cervical Plexus Block plexus may be indicated for pain of malignant origin that fails to respond to conservative measures.

CPT-2015 Code Unilateral Neurolytic

64413 64613

Relative Value Units Unilateral Neurolytic

10 20

INDICATIONS Superficial cervical plexus block is useful in the diagnosis and treatment of painful conditions in areas subserved by the nerves of the superficial cervical plexus, including post-trauma pain and pain of malignant origin. This technique also is used to provide surgical anesthesia in the distribution of the superficial cervical plexus for lesion removal, laceration repair, and carotid endarterectomy. Neurodestructive procedures of the superficial cervical

CLINICALLY RELEVANT ANATOMY The superficial cervical plexus arises from fibers of the primary ventral rami of the first, second, third, and fourth cervical nerves. Each nerve divides into an ascending and a descending branch providing fibers to the nerves above and below, respectively. This collection of nerve branches makes up the cervical plexus, which provides both sensory and motor innervation. The most important motor branch is the phrenic nerve, with the plexus also providing motor fibers to the spinal accessory nerve and to the paravertebral and deep muscles of the neck. Each nerve, with the exception of the first cervical nerve, provides significant cutaneous sensory innervation. These nerves converge at the midpoint of the sternocleidomastoid muscle at its posterior margin to provide sensory innervation to the skin of the lower mandible, neck, and supraclavicular fossa (Fig. 31-1). Terminal sensory fibers of the superficial cervical plexus contribute to nerves including the greater auricular and lesser occipital nerves (Fig. 31-2).

31

KEY WORDS cervical nerves deep cervical plexus greater auricular nerve superficial cervical plexus

superficial cervical plexus block ultrasound-guided cervical plexus block

SUPERFICIAL CERVICAL PLEXUS BLOCK

116.e1

31

SUPERFICIAL CERVICAL PLEXUS BLOCK

117

Sternocleidomastoid Lesser occipital nerve Greater auricular nerve Midpoint, the posterior border of the sternocleidomastoid and the site of skin infiltration Transverse cervical nerve Supraclavicular nerve Trapezius Clavicle

Figure 31-1

Anatomical scheme of the superficial cervical plexus emerging behind the posterior aspect of the sternocleidomastoid muscle. (From Shteif M, Lesmes D, Hartman G, et al: The use of the superficial cervical plexus block in the drainage of submandibular and submental abscesses— an alternative for general anesthesia. J Oral Maxillofac Surg 66[12]:2642-2645, 2008.)

TECHNIQUE

the superficial cervical plexus, a total of 80 mg of depotsteroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The midpoint of the posterior border of the sternocleidomastoid muscle is identified by careful palpation. After preparation of the skin with antiseptic solution, a

Landmark Technique The patient is placed in a supine position with the head turned away from the side to be blocked. A total of 15 mL of local anesthetic is drawn up in a 20-mL sterile syringe. When the treatment is for painful conditions involving

V1

V2 Lesser occipital nerve Greater auricular nerve Transverse cervical nerve

V3 C2 C4

Supraclavicular nerve Lateral Intermediate Medial

Figure 31-2

C3

Branches of the superficial cervical plexus.

118

SECTION II

NECK

Sternocleidomastoid m. Transverse cervical n.

Supraclavicular nn.

Gr. auricular n.

Gr. occipital n. Lesser occipital n.

Figure 31-3

The landmark for performing superficial cervical plexus block is the midpoint of the posterior border of the sternocleidomastoid muscle at the level of the cricoid cartilage. Gr., Greater; n./nn., nerve/nerves; m., muscle.

22-gauge, 1 1 2-inch needle is inserted at this point and is advanced just past the sternocleidomastoid muscle (Fig. 31-3). After gentle aspiration, 5 mL of solution is slowly injected. The needle is then redirected in a line that would pass just behind the lobe of the ear. After gentle aspiration, an additional 5 mL of solution is injected in a fanlike distribution. The needle is then redirected inferiorly toward the ipsilateral nipple, and after careful aspiration, the remaining 5 to 6 mL of solution is injected in a fanlike manner.

Ultrasound-Guided Technique The patient is placed in a supine position with the head turned away from the side to be blocked. A total of 15 mL of local anesthetic is drawn up in a 20-mL sterile syringe. When the treatment is for painful conditions involving the superficial cervical plexus, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The midpoint of the posterior border of the sternocleidomastoid muscle is identified by careful palpation. After preparation of the skin with antiseptic solution, a high-frequency linear ultrasound transducer is placed over this point in a transverse oblique position at essentially a right angle to the posterior border of the sternocleidomastoid muscle (Fig. 31-4). At this point the greater auricular nerve, which is one of the terminal branches of the superficial cervical plexus, will be visible twice in the same image: once in its position deep to the sternocleidomastoid muscle and then again in its superficial position as it curves back around the more superficial

surface of the muscle (Fig. 31-5). It is at this point that the superficial cervical plexus is blocked using an in-plane approach by placing a 22-gauge, 2-inch needle at the posterior border of the sternocleidomastoid muscle and advancing it under the tapered belly of the muscle toward the carotid artery, with the needle tip kept above the deeper fascia of the levator scapulae muscle (Fig. 31-6). A paresthesia may be elicited, and the patient should be warned of such. When the needle is in proximity to the greater auricular nerve, the stylet is removed and after gentle aspiration, 9 mL of solution is injected in incremental doses under real-time ultrasound imaging. The needle is removed and pressure is placed on the injection site to avoid hematoma or ecchymosis.

SIDE EFFECTS AND COMPLICATIONS The proximity to the external jugular vein and other large vessels suggests the potential for inadvertent intravascular injection or local anesthetic toxicity from intravascular absorption. The pain management specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely, especially if bilateral nerve blocks are being performed. This vascularity also gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable riskto-benefit ratio. These complications can be decreased if

31

1

SUPERFICIAL CERVICAL PLEXUS BLOCK

119

2

3

* A

B

SCM

LSM

CA

C Figure 31-4 Ultrasound-guided block of the superficial cervical plexus. A, The distribution of the cutaneous innervation of the superficial cervical plexus is outlined in white. Key surface landmarks include the sternal notch (1), the superior pole of the thyroid cartilage (2), the mastoid process (3), and the posterolateral border of the sternocleidomastoid muscle (SCM) (dashed line). The injection site is marked with an asterisk. B, Probe positioning for the in-plane approach in the lateral decubitus position. C, Survey ultrasound scan showing the tapering posterolateral border of the SCM, the carotid artery (CA), and the levator scapulae muscle (LSM). The greater auricular nerve can be identified as a hypoechoic structure above the SCM muscle (arrow) and the cervical plexus just deep to the muscle (arrowheads). (From Herring AA, Stone MB, Frenkel O, et al: The ultrasound-guided superficial cervical plexus block for anesthesia and analgesia in emergency care settings. Am J Emerg Med 30[7]:1263-1267, 2012.)

Superficial greater auricular nerve Sternocleidomastoid muscle

Deep greater auricular nerve

Carotid artery

Jugular vein

Figure 31-5 Ultrasound image demonstrating both the superficial and deep portions of the greater auricular nerve and the adjacent carotid artery and jugular vein.

manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20 minutes on, 20 minutes off, after the block also decreases the amount of postprocedure pain and bleeding the patient may experience. Not only is there the potential for complications involving the vasculature, but the proximity of the superficial cervical plexus to the central neuraxial structures and the phrenic nerve also can result in side effects and complications. If the needle is placed too deep, inadvertent epidural, subdural, or subarachnoid injection is a possibility. If the volume of local anesthetic used for this block is accidentally placed in any of these spaces, significant motor and sensory block will result. Unrecognized, these complications could be fatal. Additionally, blockade of the phrenic nerve occurs commonly after superficial cervical plexus block. In the absence of significant pulmonary disease, unilateral phrenic nerve block should rarely create respiratory embarrassment. However, if bilateral block is used for surgical indications, respiratory complications can occur.

SCM

LSM CA

A

CA

LSM

B

Figure 31-6 A, Ultrasound-guided injection of local anesthetic begins with insertion of the needle 1 to 3 cm under the tapering posterolateral border of the sternocleidomastoid muscle (SCM) just deep to the muscle belly but superficial to the deep fascia. The needle shaft is marked (arrowheads), with the needle tip beneath the greater auricular nerve (arrow). B, With injection of local anesthetic, the fascial plane should be observed in real time to distend. Generally, 8 to 10 mL is a sufficient volume. The local anesthetic will spread toward the carotid sheath but should remain superficial to the deep fascia if injected in the correct plane. CA, Carotid artery; LSM, levator scapulae muscle. (From Herring AA, Stone MB, Frenkel O, et al: The ultrasound-guided superficial cervical plexus block for anesthesia and analgesia in emergency care settings. Am J Emerg Med 30[7]:1263-1267, 2012.)

Clinical Pearls Superficial cervical plexus block is useful in the palliation of pain secondary to malignancies of the neck, including malignant melanoma, that may result in superficial tissue damage but may not invade the deep structures of the neck (Fig.

E31-1). Careful monitoring of the patient’s respiratory status should be undertaken any time bilateral superficial cervical plexus blocks are performed because the phrenic nerve is often also blocked.

31

SUPERFICIAL CERVICAL PLEXUS BLOCK

120.e1

A

B

C

Figure E31-1 Right lateral neck showing previous split-thickness skin graft. Within this, superiorly there is a well-differentiated squamous cell carcinoma (A) with a lentigo maligna inferior to it (B). A malignant melanoma arises within the lentigo maligna (C). (From Hiscutt EL, Adams JR, Ryan JM, et al: Atypical fibroxanthoma, lentigo maligna melanoma and squamous cell carcinoma arising in the site of a thermal burn treated with skin grafts. Br J Oral Maxillofac Surg 47[2]:157-158, 2009.)

120

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NECK

C H A P T E R

32

Deep Cervical Plexus Block INDICATIONS

CPT-2015 Code Unilateral Neurolytic

64413 64613

Relative Value Units Unilateral Neurolytic

12 20

Deep cervical plexus block is useful in the diagnosis and treatment of painful conditions in areas subserved by the deep cervical plexus, including post-trauma pain and pain of malignant origin. This technique is also used to provide surgical anesthesia in the distribution of the nerves of the deep cervical plexus for lesion removal, laceration repair, carotid endarterectomy, and other surgeries of the neck that require muscle relaxation. Blockade of the plexus

120.e2

SECTION II

NECK

ABSTRACT

KEY WORDS

The deep cervical plexus arises from fibers of the primary ventral rami of the first, second, third, and fourth cervical nerves. Each nerve divides into an ascending and a descending branch providing fibers to the nerves above and below, respectively. This collection of nerve branches makes up the cervical plexus, which provides both sensory and motor innervation. The most important motor branch of the cervical plexus is the phrenic nerve. The plexus also provides motor fibers to the spinal accessory nerve and to the paravertebral and deep muscles of the neck. Each nerve, with the exception of the first cervical nerve, provides significant cutaneous sensory innervation. Deep cervical plexus block is useful in the diagnosis and treatment of painful conditions in areas subserved by the deep cervical plexus, including post-trauma pain and pain of malignant origin. This technique is also used to provide surgical anesthesia in the distribution of the nerves of the deep cervical plexus for lesion removal, laceration repair, carotid endarterectomy, and other surgeries of the neck that require muscle relaxation. Blockade of the plexus with botulinum toxin has been shown to be useful in the palliation of cervical dystonias.

botulinum toxin carotid endarterectomy cervical dystonias deep cervical plexus

deep cervical plexus block phrenic nerve ultrasound-guided cervical plexus block

32

DEEP CERVICAL PLEXUS BLOCK

121

motor branch of the cervical plexus is the phrenic nerve. The plexus also provides motor fibers to the spinal accessory nerve and to the paravertebral and deep muscles of the neck. Each nerve, with the exception of the first cervical nerve, provides significant cutaneous sensory innervation. Terminal sensory fibers of the deep cervical plexus contribute fibers to the greater auricular and lesser occipital nerves.

TECHNIQUE Landmark Technique

A

B Figure 32-1 Patient with focal cervical dystonia (torticollis) before (A) and 3 months after (B) botulinum toxin injections to neck muscles. (From Hu MTM: Other movement disorders. Medicine 36[12]:636639, 2008.)

with botulinum toxin has been shown to be useful in the palliation of cervical dystonias (Fig. 32-1). Neurodestructive procedures of the deep cervical plexus may be indicated for pain of malignant origin that fails to respond to other conservative measures.

CLINICALLY RELEVANT ANATOMY The deep cervical plexus arises from fibers of the primary ventral rami of the first, second, third, and fourth cervical nerves. Each nerve divides into an ascending and a descending branch providing fibers to the nerves above and below, respectively. This collection of nerve branches makes up the cervical plexus, which provides both sensory and motor innervation (Fig. 32-2). The most important

The patient is placed in a supine position with the head turned away from the side to be blocked. A total of 15 mL of local anesthetic is drawn up in a 20-mL sterile syringe. When the treatment is for painful conditions involving the deep cervical plexus, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. A line is drawn between the mastoid process and the posterior aspect of the insertion of the sternocleidomastoid muscle at the clavicle. A point about 2 inches below the mastoid process is then identified (Fig. 32-3). After preparation of the skin with antiseptic solution, a 22gauge, 11 2-inch needle is inserted about 1 2 inch in front of the previously identified point on the line. This places the needle at the C3 or C4 level and allows a single needle to be used to block the deep cervical plexus. The needle is advanced to a depth of about 1 inch in a slightly anterior and caudad direction to avoid entering a neural foramen or slipping between the transverse process and entering the vertebral artery (Figs. 32-4 and 32-5). A paresthesia will usually be elicited, and the patient should be warned of such. If a paresthesia is not elicited, the needle should be withdrawn and redirected in a slightly anterior trajectory. Once a paresthesia is obtained and gentle aspiration reveals no evidence of blood or cerebrospinal fluid, 15 mL of solution is slowly injected in incremental doses, with monitoring of the patient for signs of local anesthetic toxicity or inadvertent subarachnoid injection.

Ultrasound-Guided Technique The patient is placed in a supine position with the head turned away from the side to be blocked. A total of 15 mL of local anesthetic is drawn up in a 20-mL sterile syringe. When the treatment is for painful conditions involving the deep cervical plexus, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. A line is drawn between the mastoid process and the posterior aspect of the insertion of the sternocleidomastoid muscle at the clavicle. The posterior border of the sternocleidomastoid muscle at the level of the superior thyroid cartilage (corresponding to approximately the C4 level) is then identified. After preparation of the skin with antiseptic solution, a high-frequency linear ultrasound transducer is placed over this point in a transverse oblique position at essentially a right angle to the posterior border

122

SECTION II

NECK

1 Hypoglossal n.

1

a.

C1

b. 2

c.

Superior root of ansa cervicalis

2 3 3

d.

4 4

Inferior root of ansa cervicalis f. Ansa cervicalis

5

5

Vertebral body C5

e. 6

Branch to an infrahyoid muscle

j.

6

g. 7

k. q. r.

Musculocutaneous n.

h.

l. n. o.

t.

8 7 i.

p.

Common carotid a.

m.

Axillary n. u.

Vertebral a.

s. Subclavian a.

w. Phrenic n.

v.

Brachiocephalic trunk

Axillary a. Median n. Radial n.

Figure 32-2

z.

y.

x.

Nerves of the cervical region, including the cervical plexus and the brachial plexus. Notice that the anterior primary divisions (ventral rami) exit posterior to the vertebral artery. The anterior primary divisions of C1 through C4 (with a contribution from C5 to the phrenic nerve) form the cervical plexus, and the anterior primary divisions of C5 through T1 form the roots of the brachial plexus. The following structures are identified: a, anterior primary division (ventral ramus) of C1, uniting with the hypoglossal nerve; b, lesser occipital nerve; c, greater auricular nerve (receives contributions from both C2 and C3 ventral rami); d, transverse cervical nerve, also known as the transverse cutaneous nerve of the neck (also receives contributions from both C2 and C3 ventral rami); e, supraclavicular nerve (common trunk of origin for lateral, intermediate, and medial supraclavicular nerves); f, dorsal scapular nerve from C5 ventral ramus would be given off here; g, upper (superior) trunk of the brachial plexus; h, middle trunk; i, lower (inferior) trunk; j, suprascapular nerve; k, anterior division of upper trunk of the brachial plexus; l, anterior division of middle trunk; m, anterior division of lower trunk; n, posterior division of upper trunk of the brachial plexus; o, posterior division of middle trunk; p, posterior division of lower trunk; q, lateral cord of the brachial plexus; r, posterior cord; s, medial cord; t, lateral pectoral nerve; u, contribution of the lateral cord to the median nerve; v, contribution of the medial cord to the median nerve; w, variant additional contribution of medial cord to the median nerve; x, medial brachial cutaneous nerve (medial cutaneous nerve of the arm); y, medial antebrachial cutaneous nerve (medial cutaneous nerve of the forearm); z, ulnar nerve. The medial pectoral nerve is shown arising from the inferior aspect of the medial cord (s). From proximal to distal, the upper subscapular, thoracodorsal, and lower subscapular nerves are shown arising from the posterior cord (r). The long thoracic nerve, which arises from the ventral rami of C5, C6, and C7, is not shown in this illustration. a., Artery; n., nerve. (From Cramer GD: The cervical region. In Cramer GD, Darby SA, editors: Clinical Anatomy of the Spine, Spinal Cord, and ANS, 3rd ed. St Louis, Mosby, 2014, pp 135-209.)

32

Sternocleidomastoid m.

Transverse process C6 (Chassaignac’s tubercle)

Cricoid cartilage

Mastoid

2

DEEP CERVICAL PLEXUS BLOCK

123

1

3 4

C2

C3

C4 C5 C6

C7

Clavicle T1

Figure 32-3

Anatomical landmarks and needle approach to deep cervical plexus blockade. m., Muscle. (From Benington S, Pichel AC: Anaesthesia for carotid endarterectomy. Curr Anaesth Crit Care 19[3]:138-149, 2008.)

Figure 32-5 Deep cervical plexus block. 1, A line is drawn along the sternocleidomastoid muscle. A parallel line is drawn connecting the posterior border of the mastoid process and the C6 lateral process. 2, C2 is usually located approximately 1.5 to 2 cm below the mastoid on this line. 3, C3 is between C2 and C4. 4, C4 can be palpated approximately two thirds of the distance from the mastoid to C6 or found on the intersection of this line and the midthyroid cartridge. The needle is advanced perpendicular to the neck with a 10- to 15-degree posterior tilt. Transverse processes are found on average 1.5 to 2.5 cm under the skin. The needle is withdrawn 2 mm, and 5 to 6 mL of local anesthetic is injected slowly at each level. Aspiration is required at all stages to prevent arteriovenous or dural penetration and inadvertent intravascular or intrathecal local anesthetic injection. (From Yastrebov K: Intraoperative management: carotid endarterectomies. Anesthesiol Clin North Am 22[2]:265-287, 2004.)

Mastoid process

Sternocleidomastoid m.

2nd cervical n.

3rd cervical n.

Clavicle 4th cervical n.

Figure 32-4

Proper needle trajectory for deep cervical plexus block. m., Muscle; n., nerve.

124

SECTION II

NECK

Lateral

Medial

Jugular vein

SCM

Levator scapulae

Carotid artery Target

Figure 32-6

Proper placement of the high-frequency linear ultrasound transducer for ultrasound-guided deep cervical plexus block.

of the sternocleidomastoid muscle (Fig. 32-6). At this point, the ultrasound transducer is slowly moved medially until the carotid artery and internal jugular vein are identified and their positions confirmed with color Doppler imaging (Fig. 32-7). It is at this point that the deep cervical plexus is blocked using an in-plane approach by placing a 22-gauge, 31 2-inch styletted spinal needle at the posterior border of the sternocleidomastoid muscle and advancing it under the tapered belly of the muscle toward the carotid artery, with the needle tip kept above the more lateral internal jugular vein (Fig. 32-8). When the needle tip is in proximity to the lateral border of the carotid artery, the stylet is removed and after gentle aspiration, 9 to 10 mL of solution is injected in incremental doses under real-time ultrasound imaging. The needle is removed and pressure is placed on the injection site to avoid hematoma or ecchymosis.

Sternocleidomastoid muscle

Jugular v.

Levator scapulae

Carotid a. Target

Lateral

Figure 32-7 Deep cervical plexus block is performed by placing the needle under the tapered belly of the sternocleidomastoid muscle toward the carotid artery, with the needle tip kept above the more lateral internal jugular vein. a., Artery; v., vein.

Figure 32-8 Ultrasound image demonstrating the target for needle tip placement when performing deep cervical plexus block. SCM, Sternocleidomastoid muscle.

SIDE EFFECTS AND COMPLICATIONS The proximity to the external jugular vein and other large vessels suggests the potential for inadvertent intravascular injection or local anesthetic toxicity from intravascular absorption. The pain management specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely, especially if bilateral nerve blocks are being performed. This vascularity also gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable riskto-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20 minutes on, 20 minutes off, after the block also decreases the amount of postprocedure pain and bleeding the patient may experience. Not only is there the potential for complications involving the vasculature, but the proximity of the deep cervical plexus to the central neuraxial structures and the phrenic nerve also can result in side effects and complications. If the needle is placed too deep, inadvertent epidural, subdural, or subarachnoid injection is a possibility. If the volume of local anesthetic used for this block is accidentally placed in any of these spaces, significant motor and sensory block will result. Unrecognized, these complications could be fatal. Additionally, blockade of the phrenic nerve occurs commonly after deep cervical plexus block. In the absence of significant pulmonary disease, unilateral phrenic nerve block should rarely create respiratory embarrassment. However, if bilateral block is used for surgical indications, respiratory complications can occur.

Clinical Pearls Deep cervical plexus block is useful in the palliation of pain secondary to malignancies of the neck that have invaded the deep structures of the neck. The use of botulinum toxin to block the deep cervical plexus represents a great advance in the treatment of cervical dystonias, including spasmodic

torticollis, a syndrome that has been notoriously hard to treat (see Fig. 32-1). Careful monitoring of the patient’s respiratory status should be undertaken any time bilateral deep cervical plexus blocks are performed because the phrenic nerve is often blocked.

33

SUPERIOR LARYNGEAL NERVE BLOCK

C H A P T E R

125

33

Superior Laryngeal Nerve Block TECHNIQUE

CPT-2015 Code Unilateral Bilateral Neurolytic

64408 64408-50 64640

Relative Value Units Unilateral Bilateral Neurolytic

10 20 20

Landmark Technique The patient is placed in a supine position with the head turned slightly away from the side to be blocked. A total of 4 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for conditions involving the superior laryngeal nerve that are thought to have an inflammatory component, including pain of malignant origin, a total of 80 mg of depot-steroid is added to the

INDICATIONS Superior laryngeal nerve block is useful in the diagnosis and treatment of painful conditions of the larynx and pharynx above the glottis, including pain of malignant origin (Fig. 33-1). Bilateral superior laryngeal nerve block is also useful as an adjunct to topical anesthesia in the performance of awake intubation, laryngoscopy, bronchoscopy, or transesophageal echocardiography.

CLINICALLY RELEVANT ANATOMY The superior laryngeal nerve arises from the vagus nerve with a small contribution from the superior cervical ganglion (Fig. 33-2). The nerve courses inferiorly and anteriorly behind the carotid arteries to pass the lateral extent of the hyoid bone (Fig. 33-3). The internal branch of this nerve provides sensory innervation to the mucous membranes of the lower portion of the epiglottis inferior to the area just above the vocal cords. An external branch provides innervation to the cricothyroid muscle.

Figure 33-1

Endoscopic appearance of a supraglottic mass. (From Morvan JB, Veyrières JB, Mimouni O, et al: Solitary fibrous tumour of the larynx: a case report. Eur Ann Otorhinolaryngol Head Neck Dis 128[5]:262-265, 2011.)

33

SUPERIOR LARYNGEAL NERVE BLOCK

ABSTRACT

KEY WORDS

The superior laryngeal nerve arises from the vagus nerve with a small contribution from the superior cervical ganglion. The nerve courses inferiorly and anteriorly behind the carotid arteries to pass the lateral extent of the hyoid bone. The internal branch of this nerve provides sensory innervation to the mucous membranes of the lower portion of the epiglottis inferior to the area just above the vocal cords. An external branch provides innervation to the cricothyroid muscle. Superior laryngeal nerve block is useful in the diagnosis and treatment of painful conditions of the larynx and pharynx above the glottis, including pain of malignant origin. Bilateral superior laryngeal nerve block is also useful as an adjunct to topical anesthesia in the performance of awake intubation, laryngoscopy, bronchoscopy, or transesophageal echocardiography.

awake intubation superior cervical ganglion superior laryngeal nerve superior laryngeal nerve block

125.e1

supraglottic transesophageal echocardiography vagus nerve

Superior laryngeal nerve

Right vagus nerve (CN X)

Left vagus nerve (CN X) Trachea

Right recurrent laryngeal nerve

Left recurrent laryngeal nerve

Esophagus

Figure 33-2

Anatomy of the superior laryngeal nerve. CN, Cranial nerve. (From Deslauriers J: Anatomy of the neck and cervicothoracic junction. Thorac Surg Clin 17[4]:529-547, 2007.)

1 cm

Tubercle of the greater horn of the hyoid bone Superior laryngeal nerve

Superior laryngeal artery

Thyrohyoid membrane

Figure 33-3 Anatomy of the superior laryngeal nerve and relationship to the cornua of the hyoid bone. (From Barral JP, Croibier A: Vagus nerve. In Manual Therapy for the Cranial Nerves. Edinburgh, Churchill Livingstone, 2009, pp 191-207.)

33

Figure 33-4

SUPERIOR LARYNGEAL NERVE BLOCK

127

Palpation of the hyoid bone.

local anesthetic with the first block, and 40 mg of depotsteroid is added with subsequent blocks. Neurolytic blocks may be performed using small, incremental doses of 6.5% aqueous phenol or absolute alcohol. The lateral border of the hyoid bone and the upper outer margin of the thyroid cartilage are identified by palpation (Fig. 33-4). At a point between these two, after preparation of the skin with antiseptic solution, a 25-gauge, 1 2-inch needle is inserted perpendicular to the skin (Fig. 33-5). The hyoid bone is manually displaced and stabilized to the side to be blocked (Fig. 33-6). After the needle is inserted to a depth of about 1 2 inch, gentle aspiration is carried out to identify blood or air that would indicate intratracheal placement. If the aspiration results are negative, 2 mL of solution is slowly

Figure 33-6 Superior laryngeal nerve block. The assistant displaces the hyoid cornu toward the side to be blocked while the operator directs the 25-gauge needle at the left hyoid cornu. (From Gil KSL, Diemunsch PA: Fiberoptic and flexible endoscopic-aided techniques. In Hagberg C, editor: Benumof and Hagberg’s Airway Management, 3rd ed. Philadelphia, Saunders, 2013, pp 365-411.e4.)

injected, with close monitoring of the patient for signs of local anesthetic toxicity.

Ultrasound-Guided Technique The patient is placed in a supine position with the head turned slightly away from the side to be blocked. A total

Int. br. of sup. laryngeal n. Hyoid bone Cricothyroid m. Sup. laryngeal n.

1st tracheal ring Cricoid cartilage

Figure 33-5

Proper needle placement for superior laryngeal nerve block. br., Branch; Ext., external; Int., internal; m., muscle; n., nerve; sup., superior.

Thyroid cartilage Ext. br. of sup. laryngeal n.

128

SECTION II

NECK

Approximate location of the superior laryngeal nerve

Superior laryngeal artery

Hyoid bone

Figure 33-7

Proper transverse placement of the high-frequency linear ultrasound transducer and proper needle trajectory for ultrasoundguided superior laryngeal nerve block.

of 4 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for conditions involving the superior laryngeal nerve that are thought to have an inflammatory component, including pain of malignant origin, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. Neurolytic blocks may be performed using small, incremental doses of 6.5% aqueous phenol or absolute alcohol. The lateral border of the hyoid bone and the upper outer margin of the thyroid cartilage are identified by palpation. The hyoid bone is manually displaced and stabilized to the side to be blocked (see Fig. 33-6). A high-frequency linear ultrasound transducer is then placed over the hyoid bone in the transverse position (Fig. 33-7). A sonogram is taken, which will demonstrate the characteristic triangular acoustic shadow of the body of the hyoid bone (Fig. 33-8).

Figure 33-9 Sonogram demonstrating the characteristic triangular shape of the hyoid bone and the relationship of the superior laryngeal artery and nerve to the hyoid bone. Just lateral and cephalad to the cornua of the hyoid bone is the approximate location of the superior laryngeal nerve (Fig. 33-9). It is at this point that the superior laryngeal nerve is blocked using an in-plane approach by placing a 22-gauge, 11 2-inch needle lateral to the hyoid bone and advancing it to a point just caudad to the triangular acoustic shadow of the body of the hyoid bone. If the periosteum of the bone is encountered, the needle is withdrawn and directed in a slightly more caudad direction. In some patients the superior laryngeal artery, which lies just below the superior laryngeal nerve, may be identified by color Doppler imaging as a landmark for ultrasound-guided block of the superior laryngeal nerve (see Fig. 33-9). When the needle is in proximity to the superior laryngeal nerve, after gentle aspiration, 4 mL of solution is injected in incremental doses under real-time ultrasound imaging. The needle is removed and pressure

Hyoid bone Superior laryngeal nerve Internal branch External branch Hyoid bone

A

B

Figure 33-8 A, Regional anatomy of the superior laryngeal nerve. B, Ultrasound image capturing the hyoid bone (arrows), which may also be suitable for guidance of superior laryngeal nerve blockade. (From Green JS, Tsui BCH: Applications of ultrasonography in ENT: airway assessment and nerve blockade. Anesthesiol Clin 28[3]:541-553, 2010.)

is placed on the injection site to avoid hematoma or ecchymosis.

SIDE EFFECTS AND COMPLICATIONS The proximity to the carotid artery, external jugular vein, and other vessels suggests the potential for inadvertent intravascular injection or local anesthetic toxicity from intravascular absorption. The pain management specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely. This vascularity also gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable risk-to-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold

packs for 20 minutes on, 20 minutes off, after the block also decreases the amount of postprocedure pain and bleeding the patient may experience. Not only is there the potential for complications involving the vasculature, but the proximity of the superior laryngeal nerve to the trachea makes intratracheal injection a possibility. Blockade of the superior laryngeal nerve puts the patient at risk of occult aspiration, especially if bilateral block is performed for diagnostic or therapeutic purposes.

Clinical Pearls Superior laryngeal nerve block is a useful technique in the palliation of pain secondary to upper airway malignancies. Although bilateral block is often required, it is recommended that only one side be blocked at a time to minimize untoward effects of the block.

34

RECURRENT LARYNGEAL NERVE BLOCK

C H A P T E R

129

34

Recurrent Laryngeal Nerve Block CPT-2015 Code Unilateral Bilateral Neurolytic

64408 64408-50 64640

Relative Value Units Unilateral Bilateral Neurolytic

10 20 20

INDICATIONS Recurrent laryngeal nerve block is useful in the diagnosis and treatment of painful conditions of the larynx arising below the vocal cords and the tracheal mucosa, including pain of malignant origin (Fig. 34-1).

CLINICALLY RELEVANT ANATOMY The recurrent laryngeal nerves arise from the vagus nerve. The right and left nerves follow different paths to

reach the larynx and trachea. The right recurrent laryngeal nerve loops underneath the innominate artery and then ascends in the lateral groove between the trachea and esophagus to enter the inferior portion of the larynx. The left recurrent laryngeal nerve loops below the arch of the aorta and then ascends in the lateral groove between the trachea and esophagus to enter the inferior portion of the larynx (Figs. 34-2 and 34-3). These nerves provide the innervation to all the intrinsic muscles of the larynx except the cricothyroid muscle and also provide the sensory innervation for the mucosa below the vocal cords (Fig. 34-4, Table 34-1).

TECHNIQUE Landmark Technique The patient is placed in a supine position with the head turned slightly away from the side to be blocked. A total of 4 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for conditions involving the recurrent laryngeal nerve that are thought to have an inflammatory component, including pain of malignant origin, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depotsteroid is added with subsequent blocks. Neurolytic

130

SECTION II

NECK

A

B

Figure 34-1 Detection of recurrent disease on positron emission tomography (PET)/computed tomography (CT) in a 67-year-old woman with T3N0 squamous cell carcinoma with dysphagia 5 months after radical chemoradiotherapy. A, Coronal maximum-intensity projection PET image shows abnormal uptake of 18-fluorodeoxyglucose (FDG) in the mediastinum (thick arrow), with a further hypermetabolic focus in the right side of the neck (thin arrow). B, Coronal fused PET/CT images localize the abnormalities to the upper thoracic esophagus, where there is a 4-cm-long section of moderate FDG uptake with a maximum standard uptake value of 9 (thick arrow), and the right vocal cord (thin arrow). These appearances were felt to be consistent with local recurrence and a left vocal cord palsy resulting from damage to the recurrent laryngeal nerve during therapy. Results of subsequent endoscopic biopsy confirmed local esophageal recurrence. (From Chowdhury FU, Bradley KM, Gleeson FV: The role of 18F-FDG PET/CT in the evaluation of oesophageal carcinoma. Clin Radiol 63[12]:1297-1309, 2008.)

Superior laryngeal nerve

Right vagus nerve (CN X)

Left vagus nerve (CN X) Trachea

Right recurrent laryngeal nerve

Left recurrent laryngeal nerve

Esophagus

Figure 34-2

Path of the recurrent laryngeal nerve. CN, Cranial nerve. (From Deslauriers J: Anatomy of the neck and cervicothoracic junction. Thorac Surg Clin 17[4]:529-547, 2007.)

blocks may be performed using small, incremental doses of 6.5% aqueous phenol or absolute alcohol. The medial border of the sternocleidomastoid muscle is identified at the level of the first tracheal ring (Fig. 34-5). At this point, after preparation of the skin with antiseptic solution, a 25-gauge, 1 2-inch needle is inserted perpendicular to the skin. After the needle is inserted to a depth of about 1 2 inch, gentle aspiration is carried out to identify blood or air that would indicate intratracheal placement. If the aspiration results are negative, 2 mL of solution is slowly injected, with close monitoring of the patient for signs of local anesthetic toxicity.

Ultrasound-Guided Technique The patient is placed in a supine position with the head turned slightly away from the side to be blocked. A total of 4 mL of local anesthetic is drawn up in a 10-mL sterile syringe. When the treatment is for conditions involving the recurrent laryngeal nerve that are thought to have an inflammatory component, including pain of malignant origin, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depotsteroid is added with subsequent blocks. Neurolytic blocks may be performed using small, incremental doses of 6.5% aqueous phenol or absolute alcohol. The medial border of the sternocleidomastoid muscle is identified at the level of the tracheal ring. At this point, after preparation of the skin with antiseptic solution, a high-frequency linear ultrasound transducer is placed over the medial border of the sternocleidomastoid muscle in the transverse position at the level of the first tracheal ring (Fig. 34-6). The trachea and esophagus are then visualized and the relative position of the carotid artery

Superficial layer, deep cervical fascia

Esophagus

Thyroid gland

Recurrent laryngeal nerve

Trachea

Visceral space

Middle layer, deep cervical fascia

Sternocleidomastoid m. Parathyroid gland

Retropharyngeal space

Carotid space

Danger zone

Int. jugular v.

Deep layer, deep cervical fascia

Vagus n. Common carotid a.

Figure 34-3 The right recurrent laryngeal nerve loops underneath the innominate artery and then ascends in the lateral groove between the trachea and esophagus to enter the inferior portion of the larynx. The left recurrent laryngeal nerve loops below the arch of the aorta and then ascends in the lateral groove between the trachea and esophagus to enter the inferior portion of the larynx. a., Artery; Int., internal; m., muscle; v., vein.

Inferior vagal ganglion

Superior thyroid artery Internal laryngeal nerve

Superior laryngeal nerve

Superior laryngeal artery

Vagus nerve (CN X)

External laryngeal nerve Cricothyroid artery Inferior laryngeal artery

Inferior thyroid artery

Recurrent laryngeal nerve

Figure 34-4

Arterial supply and neural innervation to the larynx. Note the path of the recurrent laryngeal nerve. CN, Cranial nerve. (From Thurnher D, Moukarbel RV, Novak CB, et al: The glottis and subglottis: an otolaryngologist’s perspective. Thorac Surg Clin 17[4]:549-560, 2007.)

TABLE 34-1

Intrinsic Muscles of the Larynx

Muscle

Innervation

Main Action

Posterior cricoarytenoid

Recurrent laryngeal nerve

Abducts the vocal cords

Lateral cricoarytenoid

Recurrent laryngeal nerve

Adducts the vocal cords

Thyroarytenoid (TA)

Recurrent laryngeal nerve

Relaxes the vocal cords

Vocalis (medial TA)

Recurrent laryngeal nerve

Tenses the vocal cords

Transverse (inter) and oblique arytenoid

Recurrent laryngeal nerve

Approximates the arytenoids, adducts the vocal cords

Cricothyroid

Superior laryngeal nerve, external branch

Tenses the vocal cords

132

SECTION II

NECK

Thyroid cartilage Cricothyroid m.

Hyoid bone

Cricoid cartilage 1st tracheal ring

Sup. laryngeal n.

Int. br. of sup. laryngeal n. Recurrent laryngeal n.

Ext. br. of sup. laryngeal n. Communicating branch Sternocleidomastoid m.

Ant., post. brs. inf. laryngeal nn.

Figure 34-5

Proper needle trajectory for landmark-based recurrent laryngeal nerve block. Ant., Anterior; br./brs., branch/branches; Ext., external; Inf., inferior; Int., internal; m., muscle; n./nn., nerve/nerves; post., posterior; sup., superior.

is noted (Fig. 34-7). Color Doppler imaging is then used to further delineate the carotid artery as well as to identify any significant vessels, including branches of the thyroid artery, that could be injured during needle placement. The recurrent laryngeal nerve is located in the lateral groove between the trachea and esophagus and may be identified on ultrasound as a monofascicular hypoechoic bundle with a hyperechoic perineurium in some patients (see

Thyroid gland Carotid

Esophagus

Figure 34-7 Figure 34-6

Proper transverse placement of the high-frequency linear ultrasound transducer for ultrasound-guided recurrent laryngeal nerve block.

*

Trachea

Transverse ultrasound image demonstrating the trachea and esophagus. Note the relative position of the carotid artery. The recurrent laryngeal nerve is located in the lateral groove between the trachea and esophagus and may be identified on ultrasound as a monofascicular hypoechoic bundle with a hyperechoic perineurium (asterisk).

34

RECURRENT LARYNGEAL NERVE BLOCK

133

Thyroid gland

Figure 34-8

Longitudinal ultrasound image showing the recurrent laryngeal nerve as it lies in the groove between the trachea and esophagus.

Fig. 34-7). Longitudinal ultrasound views may help confirm the identification of the nerve (Fig. 34-8). The point where the recurrent laryngeal nerve lies in the lateral groove is the target for needle placement. The recurrent laryngeal nerve is blocked using an in-plane approach by placing a 22-gauge, 11 2-inch needle at the medial margin of the transversely oriented ultrasound transducer and advancing it to the point where the recurrent laryngeal nerve lies in the lateral groove between the trachea and esophagus while avoiding the carotid artery and other vessels previously identified by color Doppler imaging. When the needle is in proximity to the recurrent laryngeal nerve, after gentle aspiration, 3 mL of solution is injected in incremental doses under real-time ultrasound imaging. The needle is removed and pressure is placed on the injection site to avoid hematoma or ecchymosis.

SIDE EFFECTS AND COMPLICATIONS The proximity to the carotid artery, external jugular vein, and other vessels suggests the potential for inadvertent intravascular injection or local anesthetic toxicity from intravascular absorption. The pain management specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely. This vascularity also gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable risk-to-benefit ratio. These complications can be

Figure 34-9

Both vocal cords are immobile in the paramedian position with a slightly glottic gap. (From Endo K, Okabe Y, Maruyama Y, et al: Bilateral vocal cord paralysis caused by laryngeal mask airway. Am J Otolaryngol 28:126-129, 2007.)

decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20 minutes on, 20 minutes off, after the block also decreases the amount of postprocedure pain and bleeding the patient may experience. The recurrent laryngeal nerves provide the innervation to all the intrinsic muscles of the larynx except the cricothyroid muscle; therefore, bilateral recurrent laryngeal nerve block is reserved for those patients who have undergone laryngectomy or tracheostomy, because the resulting bilateral vocal cord paralysis could result in airway obstruction (Fig. 34-9).

Clinical Pearls Recurrent laryngeal nerve block is a useful technique in the palliation of pain secondary to upper airway malignancies. Bilateral block should be reserved for those patients who have undergone previous laryngectomy to avoid airway obstruction from bilateral vocal cord paralysis (see Fig. 34-3). For treatment of cancer pain of the larynx and upper trachea, recurrent laryngeal nerve block often has to be combined with superior laryngeal nerve block to obtain adequate pain control.

C H A P T E R

35

Stellate Ganglion Block: Anterior Approach CLINICALLY RELEVANT ANATOMY

CPT-2015 Code Unilateral Neurolytic

64510 64680

Relative Value Units Unilateral Neurolytic

12 20

INDICATIONS Stellate ganglion block is indicated in the treatment of acute herpes zoster in the distribution of the trigeminal nerve and cervical and upper thoracic dermatomes as well as frostbite and acute vascular insufficiency of the face and upper extremities (Fig. 35-1). Stellate ganglion block is also indicated in the treatment of reflex sympathetic dystrophy of the face, neck, upper extremity, and upper thorax; Raynaud’s syndrome of the upper extremities; and sympathetically mediated pain of malignant origin. There are clinical reports to suggest that stellate ganglion blocks also may be useful in the acute palliation of some atypical vascular headaches.

Figure 35-1

External view of nasal frostbite injury before débridement. (From Jabbour N, Heman-Ackah SE, Day AT, et al: Severe nasal frostbite injury from nasal cannula supplemental oxygen malfunction. Am J Otolaryngol 32[4]:349-352, 2011.)

134

The stellate ganglion, which is also known as the inferior cervical ganglion, is located on the anterior surface of the longus colli muscle. This muscle lies just anterior to the transverse processes of the seventh cervical and first thoracic vertebrae. The stellate ganglion is made up of the fused portion of the seventh cervical and first thoracic sympathetic ganglia (Fig. 35-2). The stellate ganglion lies anteromedial to the vertebral artery and is medial to the common carotid artery and jugular vein. The stellate ganglion is lateral to the trachea and esophagus.

TECHNIQUE Landmark and Fluoroscopically Guided Techniques Landmark Technique The patient is placed in the supine position with the cervical spine in neutral position. From 7 to 10 mL of local anesthetic without preservative is drawn into a 12-mL sterile syringe. For treatment of disease processes that have a component of inflammation, such as acute herpes zoster, or disease processes with associated edema, such as reflex sympathetic dystrophy, 80 mg of methylprednisolone is added for the first block, and 40 mg of methylprednisolone is added for subsequent blocks. The medial edge of the sternocleidomastoid muscle is identified at the level of the cricothyroid notch (C6) (Fig. 35-3). The sternocleidomastoid muscle is then displaced laterally with two fingers, and the tissues overlying the transverse process of C6 (Chassaignac’s tubercle) are compressed (Fig. 35-4). The pulsations of the carotid artery are then identified under the palpating fingers (see Fig. 35-4). The skin medial to the carotid pulsation is prepared with antiseptic solution, and a 22-gauge, 11 2inch needle is advanced until contact is made with the transverse process of C6 (Fig. 35-5). If bony contact is not made with needle insertion to a depth of 1 inch, the needle is probably between the transverse processes of C6 and C7. If this occurs, the needle should be withdrawn and reinserted with a more cephalad trajectory. After bony contact is made, the needle is then withdrawn about 2 mm to bring the needle tip out of the body of the longus colli muscle. Careful aspiration is carried out, and 7 to 10 mL of solution is then injected. Fluoroscopically Guided Technique The patient is placed in the supine position with the cervical spine in neutral position. From 7 to 10 mL of local

35

STELLATE GANGLION BLOCK: ANTERIOR APPROACH

ABSTRACT

KEY WORDS

The stellate ganglion, which is also known as the inferior cervical ganglion, is located on the anterior surface of the longus colli muscle. This muscle lies just anterior to the transverse processes of the seventh cervical and first thoracic vertebrae. The stellate ganglion is made up of the fused portion of the seventh cervical and first thoracic sympathetic ganglia. The stellate ganglion lies anteromedial to the vertebral artery and is medial to the common carotid artery and jugular vein. The stellate ganglion is lateral to the trachea and esophagus. Stellate ganglion block is indicated in the treatment of acute herpes zoster in the distribution of the trigeminal nerve and cervical and upper thoracic dermatomes as well as frostbite and acute vascular insufficiency of the face and upper extremities. Stellate ganglion block is also indicated in the treatment of reflex sympathetic dystrophy of the face, neck, upper extremity, and upper thorax; Raynaud’s syndrome of the upper extremities; and sympathetically mediated pain of malignant origin.

acute vascular insufficiency chronic regional pain syndrome frostbite Horner’s syndrome

134.e1

reflex sympathetic dystrophy stellate ganglion stellate ganglion block ultrasound-guided stellate ganglion block

35

STELLATE GANGLION BLOCK: ANTERIOR APPROACH

135

Superior cervical ganglion C1 Vagus nerve (CN X) C2 Sympathetic trunk C3 Vertebral artery C4 C5

Middle cervical ganglion Nonrecurrent laryngeal nerve

C6

Inferior thyroid artery Scalenus anterior muscle Phrenic nerve Common carotid artery

Transverse process of C6 (Chassaignac’s tubercle)

C7

Stellate ganglion (inferior cervical ganglion) Subclavian artery Ansa subclavia

T1

Figure 35-2

Common carotid artery Cupula First rib Subclavian artery

Anatomy of the stellate ganglion. CN, Cranial nerve.

anesthetic without preservative and a small amount of contrast medium suitable for subarachnoid administration is drawn into a 12-mL sterile syringe. For treatment of disease processes that have a component of inflammation, such as acute herpes zoster, or disease processes with associated edema, such as reflex sympathetic dystrophy, 80 mg of methylprednisolone is added for the first block, and 40 mg of methylprednisolone is added for subsequent blocks. An anteroposterior fluoroscopic view of the

cervical spine is obtained. The vertebral bodies are counted and the C6 vertebra is identified. The operator should be careful to look for cervical ribs, which may lead to an erroneous identification of levels (Fig. 35-6). Once the C6 vertebral body is identified, the fluoroscope angle is adjusted to optimize the identification of the C6 transverse process and Chassaignac’s tubercle. As with the landmark technique, the carotid artery is carefully identified by palpation and then retracted laterally out of the needle path. A 25-gauge, 11 2-inch needle is then advanced under fluoroscopic guidance until the needle impinges on Chassaignac’s tubercle. After bony contact is made, the needle is then withdrawn about 2 mm to bring the needle tip out of the body of the longus colli muscle. Careful aspiration is carried out, and 7 to 10 mL of solution is then injected. Contrast medium can be seen to spread both above and below the site of injection (Fig. 35-7). Larger volumes of local anesthetic are to be avoided due to the increased incidence of local anesthetic–related side effects (Fig. 35-8).

Ultrasound-Guided Technique

Figure 35-3

Identification of the cricothyroid notch by palpation.

The patient is placed in the supine position with the head turned slightly away from the side to be blocked. Turning the head has the dual advantages of (1) increasing the distance between the trachea and the carotid artery, and (2) improving the view of the anatomy on ultrasound

136

SECTION II

NECK

Hyoid bone Thyroid cartilage Middle cervical ganglion Cricothyroid notch Trachea Stellate ganglion

Sympathetic trunk Common carotid a. Int. jugular v. Longus colli m.

Chassaignac s tubercle (transverse process C6)

Sternocleidomastoid m.

Figure 35-4

The sternocleidomastoid muscle is displaced laterally with two fingers, and the tissues overlying the transverse process of C6 (Chassaignac’s tubercle) are compressed. The pulsations of the carotid artery are then identified under the palpating fingers. a., Artery; Int., internal; m., muscle; v., vein.

imaging. Seven milliliters of local anesthetic is drawn up in a 10-mL sterile syringe and 40 mg to 80 mg of depotsteroid is added to the local anesthetic if there is thought to be an inflammatory component to the patient’s pain symptoms. The cricothyroid notch is identified by palpation, and the medial border of the sternocleidomastoid muscle

at the level of the cricothyroid notch is identified by palpation (see Fig. 35-3). A high-frequency linear ultrasound transducer is then placed over the medial border of the sternocleidomastoid muscle in the transverse position at the level of the cricoid notch (Fig. 35-9). This locates the transducer at approximately the C6 level. A sonogram is then obtained. The C6 vertebral body is identified by

Thyroid gland Trachea Esophagus

Int. jugular v. Vagus n. Common carotid a. Sternocleidomastoid m.

C6 vertebral body

C6 transverse process

Longus colli m. Stellate ganglion

Vertebral a.

6th cervical n.

Figure 35-5 The skin medial to the carotid pulsation is prepared with antiseptic solution, and a 22-gauge, 1 1 2-inch needle is advanced until contact is made with the transverse process of C6. a., Artery; Int., internal; m., muscle; n., nerve; v., vein.

35

137

STELLATE GANGLION BLOCK: ANTERIOR APPROACH

Anterior tubercle of transverse process (Chassaignac’s tubercle)

C6

Vertebral a.

C7 T1 Trachea

Lung

Stellate ganglion

Figure 35-6 Radiographic appearance of the cervical spine in the anteroposterior view as seen during stellate ganglion block using fluoroscopic guidance. The key anatomic structures are labeled in the inset. a., Artery. (From Janik JE, Hoeft MA, Ajar AH, et al: Variable osteology of the sixth cervical vertebra in relation to stellate ganglion block. Reg Anesth Pain Med 33[2]:102-108, 2008.)

FC

FC

FR IN

Figure 35-7

Contrast medium surrounding the stellate ganglion. (From Sekhadia MP, Nader A, Benzon HT: Peripheral sympathetic blocks. In Benzon HT, Raja SN, Fishman S, et al, editors: Essentials of Pain Medicine, 3rd ed. St Louis, Saunders, 2011, pp 621-628.)

Figure 35-8

Extensive spread of contrast medium after injection for stellate ganglion block demonstrated in a cadaver. Even a small volume of local anesthetic can spread beyond the area of the stellate ganglion. This three-dimensional computerized tomographic image was obtained after a Fogarty catheter was placed at the level of the stellate ganglion and 5 mL of contrast was injected. The Fogarty catheters (FC) remained in the right and left common carotid arteries and the injection needle (IN) is seen on the left side of the cadaver at the level of C6. On the left side, the first rib (FR) is clearly noted. The contrast reaches the second rib on both sides. (From Feigl GC, Rosmarin W, Stelzl A, et al: Comparison of different injectate volumes for stellate ganglion block: an anatomic and radiologic study. Reg Anesth Pain Med 32[3]:203-208, 2007.)

138

SECTION II

NECK

Figure 35-9

Correct transverse placement of the high-frequency ultrasound transducer for ultrasound-guided stellate ganglion block using the anterior approach.

visualizing Chassaignac’s tubercle, the unique-appearing camel-humped anterior eminence (Fig. 35-10). The C6 nerve root, the carotid artery, the longus colli muscle, and the short posterior tubercle are also identified (see Fig. 35-10). If the carotid artery blocks access to the cervical sympathetic chain, the ultrasound transducer can be slowly moved laterally to help delineate a more lateral needle trajectory to avoid the carotid artery (Fig. 35-11). If the clinician desires to inject at the C7 level to place the needle tip in closer proximity to the stellate ganglion, then once the C6 vertebral body with its characteristic camel-humped anterior tubercle is identified, the transducer can be slowly moved caudally and slightly dorsally until the C7 transverse process comes into view. The C7 transverse process can be easily distinguished from the

Figure 35-11 If the carotid artery blocks access to the cervical sympathetic chain, the ultrasound transducer can be slowly moved laterally to help delineate a more lateral needle trajectory to avoid the carotid artery. C6 transverse process by the lack of an anterior tubercle on the C7 transverse process (Fig. 35-12). At the C7 level, the C7 nerve root is located just anterior to the posterior tubercle. Once the desired level of block has been identified and the clinically relevant anatomy including the transverse process, the longus colli muscle, the carotid artery, and the exiting nerve root have been localized, a careful scan at the chosen level using color Doppler imaging is carried out to confirm that major vasculature, including the inferior thyroid artery, is not in proximity to the intended path of the needle (Fig. 35-13). The target for the needle tip is the anterior prefascial surface of the longus colli muscle where the sympathetic nerves and ganglion are

SCM

SCM

Thyroid Thyroid

CA

CA Vertebral artery

Longus colli

Esophagus

Figure 35-10

Longus colli

C6 vertebral body

The C6 vertebral body is identified by visualizing Chassaignac’s tubercle, the unique-appearing camel-humped anterior eminence. CA, Carotid artery; SCM, sternocleidomastoid muscle.

C7 vertebral body

Figure 35-12 The C7 transverse process can be easily distinguished from the C6 transverse process by the lack of an anterior tubercle on the C7 transverse process. CA, Carotid artery; SCM, sternocleidomastoid muscle.

35

STELLATE GANGLION BLOCK: ANTERIOR APPROACH

139

SIDE EFFECTS AND COMPLICATIONS SCM

Jugular vein

CA Thyroid

C7 vertebral body Inferior thyroid artery

Vertebral artery

Figure 35-13 Once the desired level of block has been identified and the clinically relevant anatomy including the transverse process, the longus colli muscle, the carotid artery, and the exiting nerve root are localized, a careful scan at the chosen level using color Doppler imaging is carried out to confirm that major vasculature, including the inferior thyroid artery, is not in proximity to the intended path of the needle. CA, Carotid artery; SCM, sternocleidomastoid muscle.

located. The skin is prepared with antiseptic solution and, using an out-of-plane approach, a 22-gauge, 31 2-inch styletted spinal needle is inserted and advanced under continuous ultrasound guidance toward the anterior prefascial surface of the longus colli muscle, with care taken to avoid the carotid artery and other vessels previously identified by color Doppler imaging. Gentle pressure against the skin with the ultrasound transducer will decrease the distance between the skin and the anterior prefascial space of the longus colli muscle. When the needle is in proximity to the prefascial surface of the longus colli muscle, after gentle aspiration, a small amount of solution is injected under real-time ultrasound imaging to observe the ballooning of the anterior prefascial space of the longus colli muscle. If the solution is seen within the muscle substance or between the muscle and the transverse process, the needle is withdrawn slightly and this maneuver is repeated until satisfactory needle placement is confirmed. Once this is accomplished, 7 mL of solution is injected in incremental doses under realtime ultrasound guidance. The needle is removed and pressure is placed on the injection site to avoid hematoma or ecchymosis.

This anatomic region is highly vascular, and because of the proximity of major vessels, the pain management specialist should carefully observe the patient for signs of local anesthetic toxicity during injection. This vascularity and proximity to major blood vessels also give rise to an increased incidence of postblock ecchymosis and hematoma formation, and the patient should be warned of such. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable risk-to-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. The application of cold packs for 20 minutes on, 20 minutes off, after the block also decreases the amount of postprocedure pain and bleeding the patient may experience. Because of the proximity to the spinal column, it is also possible to inadvertently inject the local anesthetic solution into the epidural, subdural, or subarachnoid space. At this level, even small amounts of local anesthetic placed into the subarachnoid space may result in total spinal anesthesia. If needle placement is too inferior, pneumothorax is possible, because the dome of the lung lies at the level of the C7-T1 interspace. Additional side effects associated with stellate ganglion block include inadvertent block of the recurrent laryngeal nerve with associated hoarseness and dysphagia and the sensation that there is a lump in the throat when swallowing. Horner’s syndrome occurs when the superior cervical sympathetic ganglion is also blocked during stellate ganglion block. The patient should be warned of the possibility of these complications before stellate ganglion block is performed. Clinical Pearls Properly performed stellate ganglion block is a safe and effective technique for treatment of the previously mentioned pain syndromes. Improperly performed, it can be one of the most dangerous regional anesthetic techniques used in pain management. Almost all the complications associated with stellate ganglion block can be avoided if two simple rules are always followed: (1) the C6 level must always be accurately identified and double-checked by identifying the cricothyroid notch; and (2) the needle tip must always make bony contact with the transverse process of C6 before the injection of any drugs. The patient should always be warned of the potential side effects associated with this technique, because these side effects invariably occur.

C H A P T E R

36

Stellate Ganglion Block: Posterior Approach CPT-2015 Code Unilateral Neurolytic

64510 64680

Relative Value Units Unilateral Neurolytic

12 20

INDICATIONS The posterior approach to the stellate ganglion is used in two clinical situations: (1) when infection, trauma, or tumor precludes use of the traditional anterior approach to stellate ganglion block, and (2) when neurolysis of the sympathetic innervation of the upper extremity is desired. The posterior approach to stellate ganglion block is preferred when neurolytic solutions are being used because this approach allows the needle to be placed at the more inferior T1 or T2 level and thus avoids the possibility of superior spread of neurolytic solution with resultant permanent Horner’s syndrome. Neurolysis of the sympathetic chain also can be accomplished via the anterior vertebral approach using radiofrequency lesioning. The anterior approach to stellate ganglion block is preferred in the routine treatment of acute herpes zoster in the distribution of the trigeminal nerve and cervical and upper thoracic dermatomes as well as frostbite and acute vascular insufficiency of the face and upper extremities. The anterior approach to the stellate ganglion is also indicated in the treatment of reflex sympathetic dystrophy of the face, neck, upper extremity, and upper thorax; Raynaud’s syndrome of the upper extremities; and sympathetically mediated pain of malignant origin (Fig. 36-1). There are clinical reports to suggest that stellate ganglion blocks also may be useful in the acute palliation of some atypical vascular headaches.

CLINICALLY RELEVANT ANATOMY The stellate ganglion is located on the anterior surface of the longus colli muscle. This muscle lies just anterior to the transverse processes of the seventh cervical and first thoracic vertebrae. The stellate ganglion is made up of the fused portion of the seventh cervical and first thoracic sympathetic ganglia (Fig. 36-2). The stellate ganglion lies 140

A

B Figure 36-1 A, Onycholysis and digital tuft ulceration characteristic of secondary Raynaud’s phenomenon. B, Critical ischemia with necrotic gangrene. (From Bakst R, Merola JF, Franks AG Jr, et al: Raynaud’s phenomenon: pathogenesis and management. J Am Acad Dermatol 59[4]:633-653, 2008.)

36

STELLATE GANGLION BLOCK: POSTERIOR APPROACH

ABSTRACT

KEY WORDS

The stellate ganglion, which is also known as the inferior cervical ganglion, is located on the anterior surface of the longus colli muscle. This muscle lies just anterior to the transverse processes of the seventh cervical and first thoracic vertebrae. The stellate ganglion is made up of the fused portion of the seventh cervical and first thoracic sympathetic ganglia. The stellate ganglion lies anteromedial to the vertebral artery and is medial to the common carotid artery and jugular vein. The stellate ganglion is lateral to the trachea and esophagus. Stellate ganglion block is indicated in the treatment of acute herpes zoster in the distribution of the trigeminal nerve and cervical and upper thoracic dermatomes as well as frostbite and acute vascular insufficiency of the face and upper extremities. Stellate ganglion block is also indicated in the treatment of reflex sympathetic dystrophy of the face, neck, upper extremity, and upper thorax; Raynaud’s syndrome of the upper extremities; and sympathetically mediated pain of malignant origin. The posterior approach to the stellate ganglion is used in two clinical situations: (1) when infection, trauma, or tumor precludes use of the traditional anterior approach to stellate ganglion block, and (2) when neurolysis of the sympathetic innervation of the upper extremity is desired.

acute vascular insufficiency chronic regional pain syndrome frostbite Horner’s syndrome

140.e1

posterior approach reflex sympathetic dystrophy stellate ganglion stellate ganglion block

36

STELLATE GANGLION BLOCK: POSTERIOR APPROACH

141

Superior cervical ganglion C1 Vagus nerve (CN X) C2 Sympathetic trunk C3 Vertebral artery C4 C5

Middle cervical ganglion Nonrecurrent laryngeal nerve

C6

Inferior thyroid artery Scalenus anterior muscle Phrenic nerve Common carotid artery

Transverse process of C6 (Chassaignac’s tubercle)

C7

Stellate ganglion (inferior cervical ganglion) Subclavian artery Ansa subclavia

T1

Figure 36-2

Common carotid artery Cupula First rib Subclavian artery

Anatomy of the stellate ganglion. CN, Cranial nerve.

anteromedial to the vertebral artery and is medial to the common carotid artery and jugular vein. The stellate ganglion is lateral to the trachea and esophagus. At the T1 and T2 levels, the sympathetic chain lies just anterior to the neck of the rib, lateral to the longus colli muscle (Fig. 36-3). The apex of the lung lies just lateral to the sympathetic chain at this level, which makes pneumothorax a distinct possibility. For this reason, it is recommended that this block be performed under computed tomographic (CT) or fluoroscopic guidance.

TECHNIQUE Landmark Technique The patient is placed in a prone position with the cervical spine in neutral position. From 5 to 7 mL of local anesthetic without preservative is drawn into a 12-mL sterile syringe. For disease processes that have a component of inflammation, such as acute herpes zoster, or disease processes with associated edema, such as reflex sympathetic dystrophy, 80 mg of methylprednisolone is added for the first block, and 40 mg of methylprednisolone is added for subsequent blocks. A point 4 cm lateral to the spinous process of T1-T2 is identified. The skin at this area is then prepared with antiseptic solution, and the skin and subcutaneous tissues are anesthetized with local anesthetic. A 22-gauge, 10-cm

needle is advanced until contact is made with the lamina of the target vertebra (Fig. 36-4). If bony contact is not made with needle insertion to a depth of 11 2 inches, the needle is probably either between the transverse processes of adjacent vertebrae or too lateral. If this occurs, the needle should be withdrawn and reinserted with a more caudad and medial trajectory. After bony contact is made, the needle is then withdrawn and redirected slightly laterally and inferiorly. This allows the needle to slide beneath the transverse process and rib. Ultimately the needle tip should rest just adjacent to the anterolateral border of the vertebral body in a location analogous to the final needle position when lumbar sympathetic block is performed. Careful aspiration is carried out, and 5 to 7 mL of solution is then injected. If neurolytic block is performed, small incremental doses of 6.5% aqueous phenol or absolute alcohol should be injected while the patient’s clinical response is observed.

SIDE EFFECTS AND COMPLICATIONS The main complication of the posterior approach to stellate ganglion block is pneumothorax. The use of CT guidance should help decrease the occurrence of this complication. Proximity to the aorta also represents a potential risk that can be decreased with careful attention to technique and the use of CT guidance.

142

SECTION II

NECK Sympathetic ganglion First rib Second rib Sympathetic chain

Lamina of T1

Fourth rib

1st rib T1 Apex of the lung

Stellate ganglion Sympathetic trunk Esophagus

Longus colli m.

Trachea Figure 36-4 Correct needle trajectory for stellate ganglion block using the posterior approach. m., Muscle.

Figure 36-3

At the T1 and T2 levels, the sympathetic chain lies just anterior to the neck of the rib, lateral to the longus colli muscle.

Because of the proximity to the spinal column, it is also possible to inadvertently inject the local anesthetic solution into the epidural, subdural, or subarachnoid space. At this level, even small amounts of local anesthetic placed into the subarachnoid space may result in total spinal anesthesia. Trauma to exiting spinal roots is

also a distinct possibility, especially if bony contact with the lamina of the target vertebra does not occur and the needle continues to be advanced. Inadvertent block of the recurrent laryngeal nerve with associated hoarseness and dysphagia can occur if the injectate comes in contact with this nerve. Should neurolytic solution be inadvertently injected onto this nerve, these side effects could be permanent, with devastating results for the patient. Likewise, superior spread of neurolytic solution can result in permanent Horner’s syndrome. The patient should be forewarned of the possibility of these complications before neurolytic stellate ganglion block is performed using the posterior approach.

Clinical Pearls The use of CT guidance will dramatically decrease the incidence of complications associated with this technique. Prithvi Raj reported a 4% pneumothorax rate, which suggests that this procedure should be performed only in a setting in which

chest tube placement is practical. Given the morbidity of surgical sympathectomy at this level, this technique still has a favorable risk-to-benefit ratio despite the potential for serious complications.

C H A P T E R

37

Stellate Ganglion Block: Vertebral Body Approach CPT-2015 Code Unilateral Neurolytic

64510 64680

Relative Value Units Unilateral Neurolytic

12 20

INDICATIONS Stellate ganglion block using the vertebral body approach is indicated when neurolysis of the stellate ganglion is being considered. The major advantage of this approach over the traditional anterior approach is that the placement of the needle tip against the junction of the transverse process and vertebral body decreases the possibility of inadvertent lysis of the somatic nerve roots, the phrenic nerve, or the recurrent laryngeal nerve. The disadvantage of this approach compared with the posterior approach to stellate ganglion block is the higher incidence of permanent Horner’s syndrome (Fig. 37-1). Stellate ganglion block is indicated in the treatment of acute herpes zoster in the distribution of the trigeminal nerve and cervical and upper thoracic dermatomes as well as frostbite and acute vascular insufficiency of the face and upper extremities. Stellate ganglion block is also indicated in the treatment of reflex sympathetic

Figure 37-1

Patient with left ptosis and miosis consistent with leftsided Horner’s syndrome. (From Strowd RE, Scott B, Walker FO: Black widow spider envenomation, a rare cause of Horner’s syndrome. Wilderness Environ Med 23[2]:158-160, 2012.)

dystrophy of the face, neck, upper extremity, and upper thorax; Raynaud’s syndrome of the upper extremities; and sympathetically mediated pain of malignant origin. There are clinical reports to suggest that stellate ganglion blocks also may be useful in the acute palliation of some atypical vascular headaches.

CLINICALLY RELEVANT ANATOMY The stellate ganglion is located on the anterior surface of the longus colli muscle. This muscle lies just anterior to the transverse processes of the seventh cervical and first thoracic vertebrae. The stellate ganglion is made up of the fused portion of the seventh cervical and first thoracic sympathetic ganglia (Fig. 37-2). The stellate ganglion lies anteromedial to the vertebral artery and is medial to the common carotid artery and jugular vein. The stellate ganglion is lateral to the trachea and esophagus.

TECHNIQUE Landmark and Fluoroscopically Guided Technique The patient is placed in the supine position with the cervical spine in neutral position. Three to 5 mL of local anesthetic is drawn into a 12-mL sterile syringe. For disease processes that have a component of inflammation, such as acute herpes zoster, or disease processes with associated edema, such as reflex sympathetic dystrophy, 80 mg of methylprednisolone is added for the first block, and 40 mg of methylprednisolone is added for subsequent blocks. For neurolytic blocks, 3 to 5 mL of absolute alcohol or 6.5% aqueous phenol given in incremental doses is used. Neurolytic blocks should be performed under computed tomographic (CT) or fluoroscopic guidance unless the clinical situation dictates that the block be done at the bedside. If fluoroscopic guidance is used, the junction of the C7 transverse process and the vertebral body is identified (Fig. 37-3). If a blind technique is used, the medial edge of the sternocleidomastoid muscle is identified at the level of the inferior margin of the cricoid cartilage, which is at the level of C7. The sternocleidomastoid muscle is then displaced laterally with two fingers, and the tissues overlying the transverse process of C7 are compressed. The pulsations of the carotid artery are then identified under the palpating fingers. The skin medial to the carotid pulsation is prepared with antiseptic solution, and a 22-gauge, 3 1 2-inch spinal needle is advanced with a slightly inferior and medial trajectory until contact is made with the 143

37

STELLATE GANGLION BLOCK: VERTEBRAL BODY APPROACH

ABSTRACT

KEY WORDS

The stellate ganglion, which is also known as the inferior cervical ganglion, is located on the anterior surface of the longus colli muscle. This muscle lies just anterior to the transverse processes of the seventh cervical and first thoracic vertebrae. The stellate ganglion is made up of the fused portion of the seventh cervical and first thoracic sympathetic ganglia. The stellate ganglion lies anteromedial to the vertebral artery and is medial to the common carotid artery and jugular vein. The stellate ganglion is lateral to the trachea and esophagus. Stellate ganglion block is indicated in the treatment of acute herpes zoster in the distribution of the trigeminal nerve and cervical and upper thoracic dermatomes as well as frostbite and acute vascular insufficiency of the face and upper extremities. Stellate ganglion block is also indicated in the treatment of reflex sympathetic dystrophy of the face, neck, upper extremity, and upper thorax; Raynaud’s syndrome of the upper extremities; and sympathetically mediated pain of malignant origin. Stellate ganglion block using the vertebral body approach is indicated when neurolysis of the stellate ganglion is being considered. The major advantage of this approach over the traditional anterior approach is that the placement of the needle tip against the junction of the transverse process and vertebral body decreases the possibility of inadvertent lysis of the somatic nerve roots, the phrenic nerve, or the recurrent laryngeal nerve. The disadvantage of this approach compared with the posterior approach to stellate ganglion block is the higher incidence of permanent Horner’s syndrome.

acute vascular insufficiency chronic regional pain syndrome frostbite Horner’s syndrome neurolysis

143.e1

recurrent laryngeal nerve reflex sympathetic dystrophy stellate ganglion stellate ganglion block ultrasound-guided stellate ganglion block

144

SECTION II

NECK Superior cervical ganglion C1 Vagus nerve (CN X) C2 Sympathetic trunk C3 Vertebral artery C4 C5

Middle cervical ganglion Nonrecurrent laryngeal nerve

C6

Inferior thyroid artery Scalenus anterior muscle Phrenic nerve Common carotid artery

Transverse process of C6 (Chassaignac’s tubercle)

C7

Stellate ganglion (inferior cervical ganglion) Subclavian artery Ansa subclavia

T1

Figure 37-2

Common carotid artery Cupula First rib Subclavian artery

Anatomy of the stellate ganglion. CN, Cranial nerve.

junction of the transverse process of C7 and the vertebral body (Figs. 37-4 and 37-5). If bony contact is not made with needle insertion to a depth of 1 1 2 inches, the needle is probably either too lateral or has slid between the transverse processes of C7 and T1. If this occurs, the needle should be withdrawn and reinserted with a more medial and inferior trajectory. After bony contact is made, the needle is then withdrawn slightly to bring the needle tip out of the periosteum of the junction of the transverse process and the vertebral body (see Fig. 37-4). Careful aspiration is carried out, and 3 to 5 mL of local anesthetic, steroid, or both is injected. If neurolytic solution is being used, small incremental doses are injected, with time given between doses to allow for the adequate assessment of clinical response. To obtain adequate destruction of the stellate ganglion and associated sympathetic nerves, additional increments of neurolytic solution may have to be injected at the middle of the C7 transverse process and at a point 1 cm inferior on the anteromedial margin of the vertebral body. Radiofrequency lesioning and cryoneurolysis may be safer alternatives to chemical destruction of the stellate ganglion (see Fig. 37-3).

Ultrasound-Guided Technique Figure 37-3

Needle placement for stellate ganglion block using the vertebral body approach. (From Raj PP, Lou L, Erdine S, et al, editors: Interventional Pain Management: Image-Guided Procedures, 2nd ed. Philadelphia, Saunders, 2008.)

The patient is placed in the supine position with the head turned slightly away from the side to be blocked. Turning the head has the dual advantages of (1) increasing the distance between the trachea and the carotid artery, and (2)

37

STELLATE GANGLION BLOCK: VERTEBRAL BODY APPROACH

145

Hyoid bone Thyroid cartilage Middle cervical ganglion Cricoid cartilage Trachea Vertebral body C7 C4 C5 C6

Stellate ganglion Transverse process C7

Sympathetic trunk Common carotid a. Int. jugular v. Sternocleidomastoid m. Vertebral a.

Figure 37-4 The medial edge of the sternocleidomastoid muscle is identified at the level of the inferior margin of the cricoid cartilage, which is at the level of C7. The sternocleidomastoid muscle is then displaced laterally with two fingers, and the tissues overlying the transverse process of C7 are compressed. The pulsations of the carotid artery are then identified under the palpating fingers. a., Artery; Int., internal; m., muscle; v., vein. improving the view of the anatomy on ultrasound imaging. Seven milliliters of local anesthetic is drawn up in a 10-mL sterile syringe and 40 to 80 mg of depot-steroid is added to the local anesthetic if there is thought to be an inflammatory component to the patient’s pain symptoms. The cricothyroid notch is identified by palpation, and the medial border of the sternocleidomastoid muscle at

the level of the cricothyroid notch is then identified by palpation (Fig. 37-6). A high-frequency linear ultrasound transducer is then placed over the medial border of the sternocleidomastoid muscle in the transverse position at the level of the cricoid notch (Fig. 37-7). This places the transducer at approximately the C6 level. A sonogram is then obtained. The C6 vertebral body is identified by Trachea Vertebral body C7 Stellate ganglion

Middle cervical ganglion

C5

Figure 37-5

The needle is advanced with a slightly inferior and medial trajectory until contact is made with the junction of the transverse process of C7 and the vertebral body. a., Artery.

C6

C7

Sternum

T1

Sympathetic trunk Common carotid a. Vertebral ganglion

Transverse process C7

Subclavian a. Vertebral a. 1st rib

146

SECTION II

Figure 37-6

NECK

Palpation of the cricothyroid notch.

visualizing Chassaignac’s tubercle, the unique-appearing camel-humped eminence. The transducer can be slowly moved caudally and slightly dorsally until the C7 transverse process comes into view (Fig. 37-8). The C7 transverse process can be easily distinguished from the C6 transverse process by the lack of an anterior tubercle on the C7 transverse process (Fig. 37-9). At the C7 level, the C7 nerve root is located just anterior to the posterior tubercle. Once the C7 transverse process has been identified and the clinically relevant anatomy including the longus colli muscle, carotid artery, trachea, esophagus, and exiting nerve root are localized, the hyperechoic anterior margin of the C7 transverse process is traced medially to its junction with the C7 vertebral body. This junction is the target for the needle tip when stellate ganglion block is performed using the vertebral body approach (see Fig. 37-9). The skin is prepared with antiseptic solution and, using an out-of-plane approach, a 22-gauge, 3 1 2-inch styletted spinal needle is inserted and advanced under continuous ultrasound guidance toward the junction of the C7 transverse process and the C7 vertebral body. Color

Figure 37-8

Transverse placement of ultrasound transducer to visualize the C7 transverse process.

Doppler imaging can be used to help avoid the carotid artery, inferior thyroid artery, and jugular vein. Gentle pressure against the skin with the ultrasound transducer will decrease the distance between the skin and the target. When the needle is in proximity to the junction of the C7 transverse process and the C7 vertebral body, after gentle aspiration, a small amount of solution is injected under real-time ultrasound imaging to observe the exact location of the needle tip. Once this is accomplished and satisfactory needle placement is confirmed, 7 mL of solution is injected in incremental doses under real-time ultrasound imaging. The needle is

TR CA

TG

E

LM

C7

Figure 37-7

Correct transverse placement of the high-frequency ultrasound transducer for ultrasound-guided stellate ganglion block to identify the C6 transverse process for orientation.

Figure 37-9 Target region of a stellate ganglion block using the vertebral body approach. Notice the potentially hazardous structures near the target point. The white asterisk indicates the target point for stellate ganglion block using the anterior approach, which is located directly ventral to the longus colli muscle. The yellow star indicates the target point for stellate ganglion block using the vertebral body approach. CA, Carotid artery; C7, transverse process of C7; E, esophagus; LM, longus colli muscle; TG, thyroid gland; TR, trachea. (From Siegenthaler A, Curatolo M, Eichenberger U: Ultrasound and chronic pain. Eur J Pain Suppl 4[4]:323-328, 2010.)

removed and pressure is placed on the injection site to avoid hematoma or ecchymosis.

SIDE EFFECTS AND COMPLICATIONS This anatomic region is highly vascular, and because of the proximity of major vessels, the pain management specialist should carefully observe the patient for signs of local anesthetic toxicity during injection. This vascularity and proximity to major blood vessels also give rise to an increased incidence of postblock ecchymosis and hematoma formation, and the patient should be warned of such. Despite the vascularity of this anatomic region, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable risk-to-benefit ratio. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20 minutes on, 20 minutes off, after the block also decreases the amount of postprocedure pain and bleeding the patient may experience. Because of the proximity to the spinal column, it is also possible to inadvertently inject the local anesthetic or neurolytic solution into the epidural, subdural, or subarachnoid space. At this level, even small amounts of local anesthetic placed into the subarachnoid space may result in total spinal anesthesia. Neurolytic solutions placed

onto the neuraxis at this level can result in significant neurologic dysfunction, including quadriparesis. Because of the more inferior needle placement with the vertebral body approach to stellate ganglion block, pneumothorax is a distinct possibility. These complications can be decreased with the use of radiographic guidance. Additional side effects that occur with sufficient frequency include inadvertent block of the recurrent laryngeal nerve with associated hoarseness and dysphagia and the sensation that there is a lump in the throat when swallowing. Horner’s syndrome occurs when the superior cervical sympathetic ganglion is also blocked during stellate ganglion block. These complications can be disastrous if neurolytic solution is used. The patient should be forewarned of the possibility of these complications before stellate ganglion block is performed using the vertebral body approach. Clinical Pearls The use of CT or fluoroscopic guidance will dramatically decrease the incidence of complications associated with this technique. Given the possibility of pneumothorax, this procedure should be performed only in a setting where chest tube placement is practical (Fig. E37-1). Because of the morbidity of surgical sympathectomy at this level, this technique still has a favorable risk-to-benefit ratio despite the potential for serious complications.

37

Figure E37-1

STELLATE GANGLION BLOCK: VERTEBRAL BODY APPROACH

147.e1

Chest radiograph showing left pneumothorax with shift of the mediastinum and trachea to the right side (white arrows). The left lung is not completely collapsed, which suggests the presence of a loculated tension pneumothorax. (From Chan SSW: Tension pneumothorax managed without immediate needle decompression. J Emerg Med 36[3]:242-245, 2009.)

38

STELLATE GANGLION BLOCK: RADIOFREQUENCY LESIONING

C H A P T E R

147

38

Stellate Ganglion Block: Radiofrequency Lesioning CPT-2015 Code Radiofrequency—Neurolytic

64680

Relative Value Units Radiofrequency—Neurolytic

25

INDICATIONS Radiofrequency lesioning of the stellate or cervicothoracic ganglion is indicated in the treatment of sympathetically mediated pain when the pain has repeatedly

responded to stellate ganglion block with local anesthetic, but the pain relief is not long lasting. Pain syndromes that may be amenable to radiofrequency lesioning of the stellate ganglion include vascular insufficiency of the face and upper extremities; reflex sympathetic dystrophy of the face, neck, upper extremity, and upper thorax; Raynaud’s syndrome or Buerger’s disease of the upper extremities; and sympathetically mediated pain of malignant origin (Fig. 38-1).

CLINICALLY RELEVANT ANATOMY The stellate ganglion is located on the anterior surface of the longus colli muscle. This muscle lies just anterior

147.e2

SECTION II

NECK

ABSTRACT

KEY WORDS

The stellate ganglion, which is also known as the inferior cervical ganglion, is located on the anterior surface of the longus colli muscle. This muscle lies just anterior to the transverse processes of the seventh cervical and first thoracic vertebrae. The stellate ganglion is made up of the fused portion of the seventh cervical and first thoracic sympathetic ganglia. The stellate ganglion lies anteromedial to the vertebral artery and is medial to the common carotid artery and jugular vein. The stellate ganglion is lateral to the trachea and esophagus. Radiofrequency lesioning of the stellate or cervicothoracic ganglion is indicated in the treatment of sympathetically mediated pain when the pain has repeatedly responded to stellate ganglion block with local anesthetic, but the pain relief is not long lasting. Pain syndromes that may be amenable to radiofrequency lesioning of the stellate ganglion include vascular insufficiency of the face and upper extremities; reflex sympathetic dystrophy of the face, neck, upper extremity, and upper thorax; Raynaud’s syndrome or Berger’s disease of the upper extremities; and sympathetically mediated pain of malignant origin.

acute vascular insufficiency chronic regional pain syndrome frostbite Horner’s syndrome neurolysis neurolytic stellate ganglion block

radiofrequency lesioning recurrent laryngeal nerve reflex sympathetic dystrophy stellate ganglion stellate ganglion block ultrasound-guided stellate ganglion block

148

SECTION II

NECK

A

B

C

Figure 38-1 A 27-year-old man came for angiographic investigation of progressive changes in the hands, greatest on the right, to assess for a vascular cause. A, The right hand shows protrusion of the distal phalanges through the nail bed of the second to fourth digits. The fingers are edematous and erythematous due to ischemia. There is necrosis of the nail bed of the third digit. B, Digital subtraction angiographic image (anteroposterior projection) of the right forearm shows normal proximal arteries. Within the mid forearm, the radial (thick arrow) and ulnar (thin arrow) arteries terminate, with multiple “corkscrew” collaterals visualized in the distal forearm and hand. These findings are evident in Buerger’s disease. C, Angiographic image (anteroposterior projection) of the distal forearm, wrist, and hand demonstrates corkscrew collaterals with minimal filling of the digital arteries. (From Dimmick SJ, Goh AC, Cauzza E, et al: Imaging appearances of Buerger’s disease complications in the upper and lower limbs. Clin Radiol 67[12]:1207-1211, 2012.) to the transverse processes of the seventh cervical and first thoracic vertebrae. The stellate ganglion is made up of the fused portion of the seventh cervical and first thoracic sympathetic ganglia. The stellate ganglion lies anteromedial to the vertebral artery and is medial to the common carotid artery and jugular vein (Fig. 38-2). The stellate ganglion is lateral to the trachea and esophagus.

TECHNIQUE Fluoroscopically Guided Technique The patient is placed in the supine position with the cervical spine in a slightly extended position. Three milliliters of local anesthetic combined with 3 mL of water-soluble contrast medium is drawn into a 12-mL sterile syringe.

Superior cervical ganglion C1 Vagus nerve (CN X) C2 Sympathetic trunk C3 Vertebral artery C4 C5

Middle cervical ganglion Nonrecurrent laryngeal nerve

C6

Inferior thyroid artery Scalenus anterior muscle Phrenic nerve Common carotid artery Stellate ganglion (inferior cervical ganglion) Subclavian artery Ansa subclavia

Transverse process of C6 (Chassaignac’s tubercle)

C7

T1

Figure 38-2

Anatomy of the stellate ganglion. CN, Cranial nerve.

Common carotid artery Cupula First rib Subclavian artery

38

STELLATE GANGLION BLOCK: RADIOFREQUENCY LESIONING

149

Figure 38-3 The junction of the C7 transverse process and the vertebral body (star) is identified using fluoroscopy. The intervertebral foramen is identified by the arrow. Using computed tomography (CT) or fluoroscopic guidance, the junction of the C7 transverse process and the vertebral body is identified, and the skin is marked with a gentian violet marker (Fig. 38-3). The index and ring fingers of the nondominant hand are then used to palpate the medial edge of the sternocleidomastoid muscle at the

level of the inferior margin of the cricoid cartilage, which is at the level of C7. The sternocleidomastoid muscle is then displaced laterally with two fingers, and the tissues overlying the transverse process of C7 are compressed (Fig. 38-4). The pulsations of the carotid artery are then identified under the palpating fingers. The skin medial to

Hyoid bone Thyroid cartilage Middle cervical ganglion Cricoid cartilage Trachea Vertebral body C7 C4 C5 C6 Sympathetic trunk Common carotid a. Int. jugular v. Sternocleidomastoid m.

Figure 38-4

The index and ring fingers of the nondominant hand are used to palpate the medial edge of the sternocleidomastoid muscle at the level of the inferior margin of the cricoid cartilage, which is at the level of C7. The sternocleidomastoid muscle is then displaced laterally with two fingers, and the tissues overlying the transverse process of C7 are compressed. a., Artery; Int., internal; m., muscle; v., vein.

Vertebral a.

Stellate ganglion Transverse process C7

150

SECTION II

NECK

Common carotid artery

Trachea

Vertebral body C7 Vertebral artery

C5 C6

C7

Middle cervical Stellate ganglion 1st rib ganglion Transverse process C7 Subclavian artery

Figure 38-5

A 20-gauge, curved, 54-cm radiofrequency needle with a 4-mm active tip is guided through the introducer and is advanced with a slightly inferior and medial trajectory until contact is made with the junction of the transverse process of C7 with the vertebral body.

the carotid pulsation is prepared with antiseptic solution and anesthetized with local anesthetic. Under intermittent fluoroscopic guidance, a 16-gauge introducer needle is directed toward the previously identified junction of the C7 transverse process and the vertebral body. A 20-gauge, curved, 54-cm radiofrequency needle with a 4-mm active tip is guided through the introducer and is advanced with a slightly inferior and medial trajectory until contact is made with the junction of the transverse process of C7 and the vertebral body (Figs. 38-5 and 38-6). If bony contact is not made after needle insertion to a depth of 11 2 inches, the needle is probably either too lateral or has slid between the transverse processes of C7 and T1. If this occurs, the needle should be withdrawn and reinserted with a more medial and inferior trajectory. After bony contact is made, the needle is withdrawn slightly to bring the needle tip out of the periosteum of the junction of the transverse process and the vertebral body (see Fig. 38-5). Careful aspiration is carried out, and 3 to 5 mL of the mixture of local anesthetic and contrast medium is injected. The contrast medium and local anesthetic should spread anterior to the vertebra in a cephalad and caudad direction. No epidural, subdural, subarachnoid, intramuscular, or intravascular spread of contrast medium should be observed. A trial stimulation of both the sensory nerves at 50 Hz and 0.9 V and the motor nerves at 2 Hz and 2 V should be carried out because of the proximity of the phrenic and recurrent laryngeal nerves. Stimulation of the phrenic nerve suggests that the needle is too lateral, and stimulation of the recurrent laryngeal nerve suggests that the needle is too anterior and

Figure 38-6

Proper needle placement for radiofrequency lesioning of the stellate ganglion. (From Raj PP, Lou L, Erdine S, et al, editors: Interventional Pain Management: Image-Guided Procedures, 2nd ed. Philadelphia, Saunders, 2008.)

38

STELLATE GANGLION BLOCK: RADIOFREQUENCY LESIONING

medial. Having the patient phonate with a prolonged “ee” during stimulation can help identify stimulation of these neural structures. After satisfactory needle placement has been confirmed, a radiofrequency lesion is made by heating at 80°C for 60 seconds or by pulsed radiofrequency heating at 45°C to 50°C for a longer duration. The stimulating needle is then redirected in the same plane to the most medial aspect of the transverse process, and both motor and sensory trial stimulation are repeated as described previously. If no evidence of stimulation of motor or sensory nerves is observed, a second lesion is made. The needle is then redirected to the uppermost portion of the junction of the C7 transverse process and the vertebral body. If trial stimulation fails to reveal stimulation of motor or sensory nerves, a third lesion is made. The stimulating needle is removed, and gentle pressure is placed on the site to decrease the incidence of ecchymosis and hematoma formation.

Ultrasound-Guided Technique The patient is placed in the supine position with the head turned slightly away from the side to be blocked. Turning the head has the dual advantages of (1) increasing the distance between the trachea and the carotid artery, and (2) improving the view of the anatomy on ultrasound imaging. The cricothyroid notch is identified by palpation, and the medial border of the sternocleidomastoid muscle at the level of the cricothyroid notch is then identified by palpation. A high-frequency linear ultrasound transducer is then placed over the medial border of the sternocleidomastoid muscle in the transverse position at the level of the cricoid notch (see Fig. 35-3). This locates the transducer at approximately the C6 level. A sonogram is then obtained. The C6 vertebral body is identified by visualizing Chassaignac’s tubercle, the unique-appearing camelhumped anterior eminence (see Fig. 35-10). The transducer can be slowly moved caudally and slightly dorsally until the C7 transverse process comes into view. The C7 transverse process can be easily distinguished from the C6 transverse process by the lack of an anterior tubercle on the C7 transverse process (see Fig. 35-12). At the C7 level, the C7 nerve root is located just anterior to the posterior tubercle. Once the C7 transverse process has been identified and the clinically relevant anatomy including the longus colli muscle, the carotid artery, trachea, esophagus, and exiting nerve root are localized, the hyperechoic anterior margin of the C7 transverse process is traced medially to its junction with the C7 vertebral body. This junction is the target for the needle tip when stellate ganglion block is performed using the vertebral body approach. The skin is prepared with antiseptic solution and, using an out-of-plane approach, a 16-gauge introducer needle is directed toward the previously identified junction of the C7 transverse process and the vertebral body.

151

A 20-gauge, curved, 54-cm radiofrequency needle with a 4-mm active tip is then directed through the introducer and is advanced under real-time ultrasound guidance with a slightly inferior and medial trajectory until contact is made with the junction of the transverse process of C7 and the vertebral body. Color Doppler imaging can be used to help avoid the carotid artery, inferior thyroid artery, and jugular vein. Gentle pressure against the skin with the ultrasound transducer will decrease the distance between the skin and the target. When the needle is in proximity to the junction of the C7 transverse process with the C7 vertebral body, radiofrequency lesioning is carried out as described in the previous section.

SIDE EFFECTS AND COMPLICATIONS Because of the proximity to the spinal canal, it is possible to unintentionally inject the local anesthetic into the epidural, subdural, or subarachnoid space. At this level, even small amounts of local anesthetic placed into the subarachnoid space may result in total spinal anesthesia. Radiofrequency lesioning of the neuraxial structures at this level can result in significant neurologic dysfunction, including quadriparesis. Unintentional lesioning of the phrenic nerve can result in diaphragmatic paralysis and respiratory embarrassment. Inadvertent lesioning of the recurrent laryngeal nerve can result in prolonged or permanent hoarseness. Permanent Horner’s syndrome may occur when the superior cervical sympathetic ganglion is damaged during this procedure. Because of the more inferior needle placement with the vertebral body approach to stellate ganglion block, pneumothorax is a distinct possibility, especially on the right. All of these complications can be decreased with the careful use of trial stimulation and radiographic guidance. This anatomic region is highly vascular, and because of the proximity of major vessels, the pain management specialist should carefully observe the patient for signs of local anesthetic toxicity during injection. This vascularity and proximity to major blood vessels also give rise to an increased incidence of postblock ecchymosis and hematoma formation, and the patient should be warned of such. The patient should be forewarned of the possibility of all of these complications before radiofrequency lesioning of the stellate ganglion is attempted. Clinical Pearls The use of CT, ultrasound, or fluoroscopic guidance will dramatically decrease the incidence of complications associated with this technique. Given the possibility of pneumothorax, this procedure should be performed only in a setting where chest tube placement is practical. Given the morbidity of surgical sympathectomy at this level, this technique still has a favorable risk-to-benefit ratio despite the potential for serious complications.

C H A P T E R

39

Third Occipital Nerve Block CPT-2015 Code Single Neurolytic

64490 64626

Relative Value Units Single Neurolytic

10 20

INDICATIONS Third occipital nerve block is useful in the diagnosis and treatment of third occipital nerve headache. This technique can also be used in a prognostic manner to assess the potential efficacy of destruction of the third occipital nerve with radiofrequency lesioning or other means.

CLINICALLY RELEVANT ANATOMY The third occipital nerve arises from superior branch fibers of the third cervical nerve at the level of the trapezius muscle (Fig. 39-1). The third occipital nerve courses

dorsomedially around the superior articular process of the C3 vertebra (Fig. 39-2). Fibers from the third occipital nerve provide the primary innervation of the C2-C3 facet joints with some contribution from the C3 medial branch and small communicating fibers from the second cervical nerve. Fibers of the third occipital nerve then course superiorly to provide sensory innervation to the ipsilateral suboccipital region. When the third occipital nerve is successfully blocked with local anesthetic, the patient will experience numbness in a small area behind the ipsilateral ear (Fig. 39-3).

TECHNIQUE Fluoroscopically Guided Technique The patient is placed in the prone position with the cervical spine slightly flexed. A true lateral fluoroscopic image of the upper cervical spine including the C2-C3 facet joint is then obtained. It is important to make certain that the articular pillars on each side of the C2-C3 interspace are superimposed to ensure a true lateral view. A point midway between the opposite apex of the superior articular process of C3 and the opposite base of the C2-C3 neural foramen is then identified (Fig. 39-4).

Superior oblique m.

Greater occipital nerve Anastomotic branch Inferior oblique m. Third occipital nerve

Figure 39-1 152

Posterior view of the anatomy of the third occipital nerve. m., Muscle.

Transverse process of C1 Communicating branch

Greater occipital nerve Third occipital nerve

Articular branches

Sternocleidomastoid m.

Figure 39-2 Lateral view of the anatomy of the third occipital nerve. m., Muscle.

C2–3

C3–4

Figure 39-3 Sensory distribution of the third occipital nerve (C2-C3). Pain maps shows patterns of distribution of cervical facet (zygapophysial) joint pain stemming from the C2-C3 to the C6-C7 levels. When a patient has what is suspected to be cervicogenic headache, the lateral atlantoaxial (C1-C2) and atlanto-occipital (C0-C1) joints must also be considered as possible sources. The pain maps of the C0-C1, C1-C2, C2-C3, and C3-C4 joints also overlap considerably, so although they provide clues to the possible origin of cervicogenic headache, they do not, in themselves, enable identification of the source. In the thoracic spinal region the pain maps overlap as well. (From King W, Borowczyk JM: Zygapophysial joint pain: procedures for diagnosis and treatment. In Lennard TA, Walkowski SA, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011, pp 357-389.)

C4–5

C5–6

C6–7

154

SECTION II

NECK

A

B

Figure 39-4 True lateral view of the cervical spine for identification of a point midway between the opposite apex of the superior articular process of C3 and the opposite base of the C2-C3 neural foramen. (From Raj PP, Waldman SD, Erdine S, et al: Radiographic Imaging for Regional Anesthesia and Pain Management, 1st ed. New York, Churchill Livingstone, 2002, p 159.) After preparation of the overlying skin with antiseptic solution, a 25-gauge, 11 2-inch needle is used to inject local anesthetic to anesthetize the skin and subcutaneous tissues. A 22-gauge, 31 2-inch styletted spinal needle is then inserted through the previously anesthetized area and advanced under fluoroscopic guidance toward the previously identified point that lies midway between the opposite apex of the superior articular process of C3 and the opposite base of the C2-C3 neural foramen. The needle tip will finally come to rest against the periosteum or dense facetal pericapsular fascia of the C2-C3 facet joint (Fig. 39-5). The needle is then withdrawn 2.5 to 3 mm to ensure that the needle tip is outside the facet joint. Next, 0.2 to 0.3 mL of nonionic contrast medium is injected to confirm that the needle tip is not within the facet joint, as demonstrated by pericapsular flow of contrast around the C2-C3 facet joint. A combination of 0.75 to 1.0 mL of local anesthetic and 0.25 mL of nonionic contrast medium is then gently injected under continuous fluoroscopic guidance after careful aspiration for blood and cerebrospinal fluid. Careful observation for vascular or spinal nerve root filling should be carried out during injection. Local anesthetic and contrast should be observed to spread out along the course of the third occipital nerve. Because the diameter of the third occipital nerve is greater than that of the other cervical medial branches, a second injection delivered just above the first injection point as well as a third injection delivered just below the initial injection point may be required to block the nerve completely (Figs. 39-6 and 39-7).

then prepared with antiseptic solution. The mastoid process is identified by palpation (Fig. 39-8). The superior end of a longitudinally oriented high-frequency linear ultrasound transducer is placed at the inferior border of the mastoid process and a sonogram is taken (Fig. 39-9). The mastoid process is identified (Fig. 39-10). The transducer is slowly moved in a posterior direction approximately 3 4 inch until the arch of C1 (atlas) and the articular pillar of C2 (axis) can be identified (Fig. 39-11).

Ultrasound-Guided Technique

Figure 39-5

The patient is placed in the lateral position. A total of 2 mL of local anesthetic is drawn up in a 10-mL sterile syringe. If the painful condition being treated is thought to have an inflammatory component, 40 to 80 mg of depot-steroid is added to the local anesthetic. The skin is

Lateral fluoroscopic view of the right C2-C3 facet (zygapophysial) joint with the needle tip on the skin over the target area for a third occipital nerve block injection. (From King W, Borowczyk JM: Zygapophysial joint pain: procedures for diagnosis and treatment. In Lennard TA, Walkowski SA, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011, pp 357-389.)

39

THIRD OCCIPITAL NERVE BLOCK

Figure 39-8

155

Palpation of the mastoid process.

Figure 39-6

Lateral fluoroscopic view of the right C2-C3 facet (zygapophysial) joint with the needle tip on bone at the high target point for a third occipital nerve block injection. (From King W, Borowczyk JM: Zygapophysial joint pain: procedures for diagnosis and treatment. In Lennard TA, Walkowski SA, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011, pp 357-389.)

Figure 39-9

Proper longitudinal placement of the high-frequency ultrasound transducer for identification of the mastoid process.

Figure 39-7

Lateral fluoroscopic view of the right C2-C3 facet (zygapophysial) joint with the needle tip on bone at the low target point for a third occipital nerve block injection. (From King W, Borowczyk JM: Zygapophysial joint pain: procedures for diagnosis and treatment. In Lennard TA, Walkowski SA, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011, pp 357-389.)

Mastoid process

Figure 39-10

Longitudinal ultrasound view of the mastoid process.

156

SECTION II

NECK

TON

C3-4 C2-3 C2 PILLAR

mb C3

C1 PILLAR

Figure 39-13

Figure 39-11

The transducer is slowly moved away from the mastoid process in a posterior direction approximately 3 4 inch until the arch of C1 (atlas) and the articular pillar of C2 (axis) can be identified.

The transducer is then slowly moved in a caudad direction until the C2-C3 facet joints are visualized (Fig. 39-12). The ultrasound transducer is then slowly rotated toward the acoustic auditory meatus until the third occipital nerve is identified crossing just above the “hill” of the C2-C3 facet joint (Fig. 39-13). The third occipital nerve will

Cephalad

Image of the third occipital nerve (TON) crossing the C2-C3 articulation. Typical sonographic appearance is that of an oval hypoechoic structure with hyperechoic small spots inside. In this case, the TON is situated slightly more superficial to the joint (about 2 mm) than the usual 1 mm. Between the C2-C3 and C3-C4 articulations at the deepest point, the medial branch of C3 (mb C3) can be seen as a hypoechoic oval structure. (From Siegenthaler A, Narouze S, Eichenberger U: Ultrasound-guided third occipital nerve and cervical medial branch nerve blocks. Tech Reg Anesth Pain Manag 13[3]:128-132, 2009.)

appear as a hyperechoic dot within a hypoechoic halo. The larger medial branch of C3 can also be visualized in the “valley” between the articulations of the C2-C3 facet and the C3-C4 facet joints. When the third occipital nerve is identified, a 31 2-inch needle is inserted anterior to the ultrasound transducer using an out-of-plane approach and is advanced with an anterior to posterior trajectory until the needle approaches the third occipital nerve. After gentle aspiration, 2 mL of solution is injected with care taken to avoid the vertebral artery, which is located anterior to the facet joints. The needle is removed and pressure is placed on the injection site to avoid hematoma formation.

SIDE EFFECTS AND COMPLICATIONS

TON C/4

C2/C3 mb C3

Figure 39-12

The high-frequency linear transducer is slowly moved in a caudad direction until the C2-C3 facet joints are visualized. mb, Medial branch of C3; TON, third occipital nerve.

Because this area is highly vascular, and because the third occipital nerves are in close proximity to the vertebral arteries, the pain management specialist should carefully observe the patient undergoing third occipital nerve block for inadvertent intravascular injection, which can cause significant central nervous system side effects, including ataxia, dizziness, and, rarely, seizures. The proximity of the third occipital nerve to exiting spinal nerve roots makes trauma to the nerve roots and inadvertent subarachnoid, subdural, or epidural injection a distinct possibility. Care must be taken to avoid inadvertent needle placement into the foramen magnum, because the subarachnoid administration of local anesthetic in this region will result in immediate total spinal anesthesia.

Clinical Pearls Third occipital nerve headache may be an underdiagnosed type of chronic daily headache, especially after trauma to the upper cervical spine. The most common reason that third occipital nerve block fails to relieve headache pain thought to be subserved by the third occipital nerve is that the headache syndrome being treated has been misdiagnosed as third occipital nerve headache. In the author’s experience, third occipital nerve headache is an infrequent cause of headaches in the absence of trauma. More often, the patient with headaches involving the occipital region is in fact suffering from tensiontype headaches or, less commonly, occipital neuralgia. Tensiontype headaches do not respond to third occipital nerve blocks but are amenable to treatment with antidepressant compounds such as amitriptyline in conjunction with cervical

steroid epidural nerve blocks. Therefore, the pain management specialist should reconsider the diagnosis of third occipital nerve headaches in those patients whose symptoms are consistent with third occipital nerve headaches but fail to respond to third occipital nerve block. Any patient with headaches severe enough to require neural blockade as part of the treatment plan should undergo magnetic resonance imaging of the head to rule out unsuspected intracranial disease that may mimic the clinical symptoms of third occipital nerve headache (Fig. E39-1). Furthermore, cervical spine radiography should be considered to rule out congenital abnormalities such as Arnold-Chiari malformations that may be the hidden cause of the patient’s occipital headaches.

39

A

THIRD OCCIPITAL NERVE BLOCK

157.e1

B

C Figure E39-1 Hemangiopericytoma in the floor of the posterior cranial fossa on the right. Axial T1-weighted (A) and T2-weighted (B) magnetic resonance images show a large, well-circumscribed, lobulated, homogeneously hypointense (T1 weighting) and hyperintense (T2 weighting) extraaxial mass (arrows) that deeply invaginates and displaces the inferior aspect of the right cerebellar hemisphere and vermis medially across the midline and indents the right posterolateral aspect of the medulla. C, After intravenous administration of gadolinium, intense homogeneous contrast enhancement is noted in this lobulated tumor (arrow). (From Haaga JR, Lanzieri CF: In Haaga JR, Dogra VS, Forsting M, et al, editors: CT and MR Imaging of the Whole Body, 4th ed. St Louis, Mosby, 2002, p 172.)

40

THIRD OCCIPITAL NERVE BLOCK: RADIOFREQUENCY LESIONING

C H A P T E R

157

40

Third Occipital Nerve Block: Radiofrequency Lesioning CPT-2015 Code Neurolytic

64626

Relative Value Units Neurolytic

nerve provide the primary innervation of the C2-C3 facet joints with some contribution from the C3 medial branch and small communicating fibers from the second cervical nerve. Fibers of the third occipital nerve then course superiorly to provide sensory innervation to the ipsilateral suboccipital region (Fig. 40-3).

25

TECHNIQUE INDICATIONS Radiofrequency lesioning of the third occipital nerve block is useful in the treatment of third occipital nerve headache in patients who have shown a response to block of the third occipital nerve with local anesthetic but have failed to obtain long-lasting relief.

CLINICALLY RELEVANT ANATOMY The third occipital nerve arises from superior branch fibers of the third cervical nerve at the level of the trapezius muscle (Fig. 40-1). The third occipital nerve courses dorsomedially around the superior articular process of the C3 vertebra (Fig. 40-2). Fibers from the third occipital

The patient is placed in the prone position with the cervical spine slightly flexed (Fig. 40-4). A true lateral fluoroscopic image of the upper cervical spine including the C2-C3 facet joint is then obtained (Fig. 40-5). It is important to make certain that the articular pillars on each side of the C2-C3 interspace are superimposed to ensure a true lateral view. A point midway between the opposite apex of the superior articular process of C3 and the opposite base of the C2-C3 neural foramen is then identified (Fig. 40-6). After preparation of the overlying skin with antiseptic solution, a 25-gauge, 1 1 2-inch needle is used to inject local anesthetic to anesthetize the skin and subcutaneous tissues. A 22-gauge, 15-cm insulated blunt curved needle with a 10-mm active tip is inserted through an introducer needle and is then advanced under fluoroscopic

158

SECTION II

NECK

Superior oblique m.

Greater occipital nerve Anastomotic branch Inferior oblique m. Third occipital nerve

Figure 40-1

Posterior view of the anatomy of the third occipital nerve. m., Muscle.

Transverse process of C1 Communicating branch

Greater occipital nerve Third occipital nerve

Articular branches

Figure 40-2

Sternocleidomastoid m.

Lateral view of the anatomy of the third occipital nerve. m., Muscle.

40

THIRD OCCIPITAL NERVE BLOCK: RADIOFREQUENCY LESIONING

159

C2–3

C3–4

C4–5

C5–6

C6–7

Figure 40-3

Sensory distribution of the third occipital nerve (C2-C3). (From King W, Borowczyk JM: Zygapophysial joint pain: procedures for diagnosis and treatment. In Lennard TA, Walkowski SA, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011, pp 357-389.)

Figure 40-4 The patient is placed in the prone position with the cervical spine slightly flexed.

guidance as described earlier toward the previously identified point midway between the opposite apex of the superior articular process of C3 and the opposite base of the C2-C3 neural foramen (Fig. 40-7). When the needle is in position, impedance is measured and should be in the range of 250 to 500 Ω. Proper placement of the needle is confirmed if motor stimulation at 2 Hz with 0.5 to 1.5 V produces no motor stimulation of the ipsilateral muscles of the face or upper extremity. A mild paresthesia in the distribution of the third occipital nerve may be elicited by stimulating at 50 Hz with 0.1 to 0.75 V. The needle should be repositioned if the patient complains of any unpleasant paresthesias or pain in the face. Careful aspiration for blood and cerebrospinal fluid (CSF) is then carried out and the needle is repositioned until blood is not present. If no CSF or blood is noted, 0.25 to 0.5 mL of 0.2% ropivacaine is then injected, and the patient is monitored closely for

160

SECTION II

NECK

A

B

Figure 40-5

True lateral view of the cervical spine. (From Raj PP, Waldman SD, Erdine S, et al: Radiographic Imaging for Regional Anesthesia and Pain Management, 1st ed. New York, Churchill Livingstone, 2002, p 159.)

inadvertent intravascular or subarachnoid injection. After 60 seconds, radiofrequency lesioning is carried out at 80° C for 90 seconds. Because the diameter of the third occipital nerve is greater than that of the other cervical medial branches, a second radiofrequency lesion at the inferior articular process of C2 and occasionally a third lesion at the superior articular facet of C3 is required to destroy the nerve completely.

SIDE EFFECTS AND COMPLICATIONS

Figure 40-6

Lateral fluoroscopic view of radiofrequency lesioning of the third occipital nerve. (From Soto E, Bobr V, Bax JA: Interventional techniques for headaches. Tech Reg Anesth Pain Manag 16[1]:30-40, 2012.)

Because this area is highly vascular, and because the third occipital nerves are in close proximity to the vertebral arteries, the pain management specialist should carefully observe the patient undergoing third occipital nerve block for inadvertent intravascular injection, which can cause significant central nervous system side effects, including ataxia, dizziness, and, rarely, seizures. Proximity of the third occipital nerve to exiting spinal nerve roots makes trauma to the nerve roots and inadvertent subarachnoid, subdural, or epidural injection a distinct possibility. Care must be taken to avoid inadvertent needle placement into the foramen magnum, because the subarachnoid administration of local anesthetic in this region will result in an immediate total spinal anesthesia.

Inferior articular process of C2 Third occipital nerve

Superior articular process of C3

Figure 40-7 Proper needle position for radiofrequency lesioning of the third occipital nerve. Clinical Pearls Third occipital nerve headache may be an underdiagnosed type of chronic daily headache, especially after trauma to the upper cervical spine. The most common reason that third occipital nerve block fails to relieve headache pain thought to be subserved by the third occipital nerve is that the headache syndrome being treated has been misdiagnosed as third occipital nerve headache. In the author’s experience, third occipital nerve headache is an infrequent cause of headaches in the absence of trauma. More often, the patient with headaches involving the occipital region is in fact suffering from tensiontype headaches or, less commonly, occipital neuralgia. Tensiontype headaches do not respond to third occipital nerve blocks

but are amenable to treatment with antidepressant compounds such as amitriptyline in conjunction with cervical steroid epidural nerve blocks. Therefore, the pain management specialist should reconsider the diagnosis of third occipital nerve headaches in patients whose symptoms are consistent with third occipital nerve headaches but fail to respond to third occipital nerve block. Any patient with headaches severe enough to require neural blockade as part of the treatment plan should undergo magnetic resonance imaging of the head to rule out unsuspected intracranial disease that may mimic the clinical symptoms of occipital neuralgia.

41

CERVICAL FACET BLOCK: MEDIAL BRANCH TECHNIQUE

C H A P T E R

41

Cervical Facet Block: Medial Branch Technique Relative Value Units

CPT-2015 Code First Joint Second Joint Third and Any Additional Joint

64490 64491 64492

First Joint Second Joint Third Plus Any Additional Joint

10 10 10

161

41

CERVICAL FACET BLOCK: MEDIAL BRANCH TECHNIQUE

ABSTRACT

KEY WORDS

The cervical facet joints are formed by the articulations of the superior and inferior articular facets of adjacent vertebrae. Each facet joint receives innervation from two spinal levels. Each joint receives fibers from the dorsal ramus at the same level as the vertebra as well as fibers from the dorsal ramus of the vertebra above. This fact has clinical import in that it provides an explanation for the ill-defined nature of facet-mediated pain and also explains why the dorsal nerve from the vertebra above the offending level often must also be blocked to provide complete pain relief. At each level, the dorsal ramus provides a medial branch that wraps around the convexity of the articular pillar of its respective vertebra. This location is constant for the C4-C7 nerves and allows a simplified approach to treatment of cervical facet syndrome. Cervical facet block using the medial branch technique is useful in the diagnosis and treatment of painful conditions involving trauma, arthritis, or inflammation of the cervical facet joints.

arthritis cervical facet block cervical medial branch block cervicalgia

161.e1

headache medial branch neck pain radiofrequency lesioning

162

SECTION II

NECK

C2–3

C3–4

C4–5

C5–6

C6–7

Figure 41-1 (From King W, Borowczyk JM: Zygapophysial joint pain: procedures for diagnosis and treatment. In Lennard TA, Walkowski SA, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011, pp 357-389.)

INDICATIONS Cervical facet block using the medial branch technique is useful in the diagnosis and treatment of painful conditions involving trauma, arthritis, or inflammation of the cervical facet joints. These problems may manifest clinically as neck pain, suboccipital headache, and occasionally shoulder and supraclavicular pain (Fig. 41-1).

CLINICALLY RELEVANT ANATOMY The cervical facet joints are formed by the articulations of the superior and inferior articular facets of adjacent vertebrae. Except for the atlanto-occipital and atlantoaxial joints, the cervical facet joints are true joints in that they are lined with synovium and possess a true joint capsule. This capsule is richly innervated, which supports the notion of the facet joint as a pain generator. The cervical facet joint is susceptible to arthritic changes and trauma caused by acceleration-deceleration injuries (Fig. 41-2). Such damage to the joint results in pain secondary to synovial joint inflammation and adhesions. Each facet joint receives innervation from two spinal levels. Each joint receives fibers from the dorsal ramus at the same level as the vertebra as well as fibers from the dorsal ramus of the vertebra above. This fact has clinical import in that it provides an explanation for the illdefined nature of facet-mediated pain and also explains

Figure 41-2

Lateral radiograph of the cervical spine of a 50-year-old woman with rheumatoid arthritis. Note the fusion of the facet joints in C2 through C6. There is narrowing of the spinal canal at the level of C1-C2 due to anterior displacement of the atlas. The entire spine is osteopenic. (From Bullough PG: Disc disease and spinal arthritis. In Orthopaedic Pathology, 5th ed. Philadelphia, Mosby, 2010, pp 303-319.)

41

CERVICAL FACET BLOCK: MEDIAL BRANCH TECHNIQUE

163

Sympathetic ganglion

Vertebral a. Gray ramus communicans Anterior primary division (ventral ramus) Intervertebral disk

Recurrent meningeal n.

Posterior primary division (dorsal ramus)

Mixed spinal nerve

Superior articular facet

Epidural space Dura mater

Figure 41-3

Superior view of a typical cervical segment showing the neural elements. Notice the dorsal and ventral roots, spinal nerve, and posterior and anterior primary divisions (dorsal and ventral rami). The posterior primary division can be seen dividing into a medial and a lateral branch. The recurrent meningeal nerve is shown entering the intervertebral foramen. Fibers arising from the middle cervical ganglion and the gray communicating ramus also are shown. Notice that these fibers supply the anterior and lateral aspects of the intervertebral disk, vertebral body, and anterior longitudinal ligament. a., Artery; n., nerve. (From Cramer GD: The cervical region. In Cramer GD, Darby SA, editors: Clinical Anatomy of the Spine, Spinal Cord, and ANS, 3rd ed. St Louis, Mosby, 2014, pp 135-209.)

why the dorsal nerve from the vertebra above the offending level often must also be blocked to provide complete pain relief. At each level, the dorsal ramus provides a medial branch that wraps around the convexity of the articular pillar of its respective vertebra. This location is constant for the C4-C7 nerves and allows a simplified approach to treatment of cervical facet syndrome (Fig. 41-3).

TECHNIQUE Landmark and Fluoroscopically Guided Techniques Cervical facet block using the medial branch technique is the preferred method of treating cervical facet syndrome. It may be performed blind or under fluoroscopic guidance. The patient is placed in the prone or sitting position (Fig. 41-4). Pillows are placed under the chest to allow the cervical spine to be moderately flexed without discomfort to the patient. The forehead is allowed to rest on a folded blanket.

Figure 41-4 The patient is placed in the sitting position with the forehead resting comfortably on a folded blanket.

164

SECTION II

NECK

Landmark Technique If a blind technique is used, the spinous process at the level to be blocked is identified by palpation. A point slightly inferior and 2.5 cm lateral to the spinous process is then identified as the site of needle insertion. After preparation of the skin with antiseptic solution, a skin wheal of local anesthetic is raised at the site of needle insertion. Three milliliters of preservative-free local anesthetic is drawn up in a 5-mL sterile syringe. When the treatment is for pain thought to be secondary to an inflammatory process, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. An 18-gauge, 1-inch needle is inserted through the skin and into the subcutaneous tissue at the previously identified insertion site to serve as an introducer. The introducer needle is then repositioned with a slightly superior and medial trajectory, pointing directly toward the posterior aspect of the articular pillar at the level to be blocked. A 25-gauge, 3 1 2-inch styletted spinal needle is then inserted through the 18-gauge introducer and directed toward the articular pillar. After bony contact is made, the depth of the contact is noted, and the spinal needle is withdrawn. The introducer needle is then repositioned, aiming toward the lateral-most aspect of the articular pillar. The 25-gauge spinal needle is then readvanced until it impinges on the lateral-most aspect of the border of the articular pillar (Fig. 41-5). Should the spinal needle walk off the lateral aspect of the articular pillar, it is withdrawn and redirected slightly medially and carefully advanced to the depth of the previous bony contact (Fig. 41-6).

After the needle is felt to be in a satisfactory position, the stylet is removed from the 25-gauge spinal needle, and the hub is observed for blood or cerebrospinal fluid. If neither is present, gentle aspiration of the needle is carried out. If the aspiration results are negative, 1.5 mL of solution is injected through the spinal needle. Fluoroscopically Guided Technique If fluoroscopy is used, the beam is rotated in a sagittal plane from anterior to posterior position, which allows identification and visualization of the articular pillars of the respective vertebrae. After the skin is prepared with antiseptic solution, a skin wheal of local anesthetic is raised at the site of needle insertion. An 18-gauge, 1-inch needle is inserted at the insertion site to serve as an introducer. The fluoroscope beam is aimed directly through the introducer needle, which will appear as a small point on the fluoroscopy screen. The introducer needle is then repositioned under fluoroscopic guidance until this small point is visualized pointing directly toward the posterior aspect of the articular pillar at the level to be blocked. A total of 5 mL of contrast medium suitable for intrathecal use is drawn up in a sterile 12-mL syringe. Then 3 mL of preservative-free local anesthetic is drawn up in a separate 5-mL sterile syringe. When the treatment is for pain thought to be secondary to an inflammatory process, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. A 25-gauge, 3 1 2-inch styletted spinal needle is then inserted through the 18-gauge introducer and directed toward the articular pillar. After bony contact is made,

C4 C5

C6

Figure 41-5 Med. brs. of post. primary ramus

Posterior view of the cervical spine demonstrating the proper needle trajectory to place the needle tip in proximity to the medial branch. Med. brs., Medial branches; post., posterior.

41

CERVICAL FACET BLOCK: MEDIAL BRANCH TECHNIQUE

165

Spinous process

Medial br. of post. primary ramus Lat. br. of post. primary ramus

Sup. articular process

Cross-sectional view of the C5 verterbra demonstrating the relationship of the medial branch of the primary ramus and the articular pillar. Note the position of the cervical nerve root and vertebral artery. a., Artery; Ant., anterior; br., branch; Lat., lateral; Post., posterior; Sup., superior.

Post. tubercle

C5

Figure 41-6

Ant. ramus

Vertebral body

Spinal ganglion

the spinal needle is withdrawn, and the introducer needle is repositioned toward the lateral-most aspect of the articular pillar (Figs. 41-7 and 41-8). The 25-gauge spinal needle is then readvanced until it impinges on the lateralmost aspect of the border of the articular pillar (Figs. 41-9 and 41-10). After needle placement is confirmed by biplanar fluoroscopy, the stylet is removed from the 25-gauge spinal needle, and the hub is observed for blood or cerebrospinal fluid. If neither is present, gentle aspiration of the

Vertebral a.

Ant. tubercle

needle is carried out. If the aspiration results are negative, 1 mL of contrast medium is slowly injected under fluoroscopic guidance to reconfirm needle placement. After correct needle placement is confirmed, 1.5 mL of local anesthetic with or without steroid is injected through the spinal needle.

MB MB Medial branch block MB MB Intra-articular block

Figure 41-7

Cervical facet (zygapophysial) joint blocks (medial branch [MB] and intra-articular). (From Mehio AK, Shah SK: Alleviating head and neck pain. Otolaryngol Clin North Am 42[1]:143-159, 2009.)

Figure 41-8 Anteroposterior view showing correct placement of the needle in cervical medial branch block. Note that the tip of the needle is at the waist of the articular pillar. (From Clemans RR, Benzon HT: Facet syndrome: facet joint injections and facet nerve blocks. In Benzon HT, Raja SN, Molloy RE, et al, editors: Essentials of Pain Medicine and Regional Anesthesia, 2nd ed. Philadelphia, Churchill Livingstone, 2005, pp 348-355.)

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A

Figure 41-10

pillar.

Needle tip at the lateral-most aspect of the articular

B Figure 41-9

Landmarks for needle placement in the lateral approach to cervical medial branch block using fluoroscopic guidance. A, Center of the trapezoidal lateral body. B, Lateral view of the neck showing the tip of the needle at the center of the trapezoidal lateral body of C4-C5 and C6 for cervical facet medial branch block. (From Aeschbach A, Mekhail NA: Common nerve blocks in chronic pain management. Anesthesiol Clin North Am 18[2]:429-459, 2000.)

Figure 41-11

Palpation of the mastoid process.

Ultrasound-Guided Technique For ultrasound-guided third occipital nerve block, the patient is placed in the lateral position. A total of 2 mL of local anesthetic is drawn up in a 10-mL sterile syringe. If the painful condition being treated is thought to have an inflammatory component, 40 mg to 80 mg of depotsteroid is added to the local anesthetic. The skin is then prepared with antiseptic solution. The mastoid process is identified by palpation (Fig. 41-11). The superior end of a longitudinally oriented high-frequency linear ultrasound transducer is placed at the inferior border of the mastoid process and a sonogram is taken (Fig. 41-12). The mastoid process is identified (Fig. 41-13). The transducer is then slowly moved in a posterior direction approximately 3 4 inch until the arch of C1 (atlas) and the articular pillar of C2 (axis) can be identified (Fig. 41-14). The transducer is then slowly moved in a caudad direction until the C2-C3 facet joints are

Figure 41-12 Proper longitudinal placement of the high-frequency ultrasound transducer for identification of the mastoid process.

41

167

CERVICAL FACET BLOCK: MEDIAL BRANCH TECHNIQUE

Cephalad

Mastoid process TON

Figure 41-13

Longitudinal ultrasound view of the mastoid process.

C4

C2/C3 mb C3

visualized (Fig. 41-15). Beginning with the C2-C3 facet joints, this process is repeated by slowly moving the ultrasound transducer in a caudad direction while counting the “hills” that represent the articulations of each joint until the specific facet joint to be blocked is identified (Fig. 41-16). Once the facet joints of the desired level are identified, the ultrasound transducer is slowly rotated toward the external acoustic meatus until the cervical medial branch is identified in the “valley” between adjacent facet joints. The cervical medial branches will appear as a hyperechoic dot within a hypoechoic halo (Fig. 41-17). When the cervical medial branch is identified, a 3 1 2inch needle is inserted anterior to the ultrasound transducer using an out-of-plane approach and is advanced with an anterior to posterior trajectory away from the

Figure 41-15

The high-frequency linear transducer is slowly moved in a caudad direction until the C2-C3 facet joints are visualized. mb, Medial branch; TON, third occipital nerve.

vertebral artery and neuraxial structures until the needle approaches the cervical medial branch. After gentle aspiration, 1 mL of solution is injected with care being taken to avoid the vertebral artery, which is located anterior to the facet joints. The needle is removed and pressure is placed on the injection site to avoid hematoma formation.

SIDE EFFECTS AND COMPLICATIONS The proximity to the spinal cord and exiting nerve roots makes it imperative that this procedure be carried out

C4 C5

C6

C7

T1

C2 PILLAR C1 PILLAR

Figure 41-14

The transducer is slowly moved away from the mastoid process in a posterior direction approximately 3 4 inch until the arch of C1 (atlas) and the articular pillar of C2 (axis) can be identified.

Figure 41-16

Beginning at the C2-C3 facet joints, the ultrasound transducer is slowly moved in a caudad direction while the “hills” that represent the articulations of each joint are counted until the specific facet joint to be blocked is identified.

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C4/5

C3/4

mb C4

mb C5 C5/6

Figure 41-17 Once the facet joints of the desired level are identified, the ultrasound transducer is slowly rotated toward the external acoustic meatus until the cervical medial branch (mb) is identified in the “valley” between adjacent facet joints. The cervical medial branches will appear as a hyperechoic dot within a hypoechoic halo. only by those well versed in the regional anatomy and experienced in performing interventional pain management procedures. The proximity to the vertebral artery, combined with the vascular nature of this anatomic region, makes the potential for intravascular injection high. Even small amounts of local anesthetic injected into

the vertebral arteries will result in seizures. Given the proximity of the brain and brain stem, ataxia due to vascular uptake of local anesthetic is not an uncommon occurrence after cervical facet block. Many patients also complain of a transient increase in headache and cervicalgia after injection into the joint.

Clinical Pearls Cervical facet block using the medial branch approach is the preferred technique for treatment of cervical facet syndrome. Although intra-articular placement of the needle into the facet joint is technically feasible, such maneuvers add nothing to the efficacy of the procedure unless specific diagnostic information about that joint is required and in fact may increase the rate of complications. Cervical facet block is often combined with atlantooccipital block when treating pain in the previously mentioned areas. Although the atlanto-occipital joint is not a true facet

joint in the anatomic sense of the word, the atlanto-occipital block technique is analogous to the facet joint block technique used commonly by pain practitioners and may be viewed as such. Many pain management specialists believe that these techniques are currently underused in the treatment of postwhiplash cervicalgia and cervicogenic headaches. These specialists believe that both techniques should be considered when cervical epidural nerve blocks and occipital nerve blocks fail to provide palliation of these headache and neck pain syndromes.

C H A P T E R

42

Cervical Facet Neurolysis: Radiofrequency Lesioning of the Cervical Medial Branch CPT-2015 Code Radiofrequency Lesioning First Joint Radiofrequency Lesioning Second Joint

64626 64627

Relative Value Units Radiofrequency Lesioning First Joint Radiofrequency Lesioning Second Joint

20 20

INDICATIONS Radiofrequency neurolysis of the cervical facet joints by disruption of the medial branch of the primary posterior rami is indicated for patients who experienced significant, but short-lived, pain relief following blockade of the corresponding medial branches of the cervical facets with local anesthetic on at least two occasions. This technique is useful in providing long-lasting pain relief for painful conditions involving trauma, arthritis, or inflammation of the cervical facet joints. These problems may manifest clinically as neck pain, occipital headache, and shoulder and supraclavicular pain (Fig. E42-1).

CLINICALLY RELEVANT ANATOMY The cervical facet joints are formed by the articulations of the superior and inferior articular facets of adjacent vertebrae. Except for the atlanto-occipital and atlantoaxial joints, the cervical facet joints are true joints in that they are lined with synovium and possess a true joint capsule. This capsule is richly innervated, which supports the notion of the facet joint as a potential pain generator. The cervical facet joint is susceptible to arthritic changes and trauma caused by hyperextension and hyperflexion acceleration-deceleration injuries (see Fig. E42-1). Such damage to the joint results in pain secondary to capsular disruption, synovial joint inflammation, and adhesions. Each facet joint receives innervation from two spinal levels. Each joint receives fibers from the dorsal ramus of the two levels comprising the articular surfaces. This fact has clinical import in that it provides an explanation for the ill-defined nature of facet-mediated pain and also explains why the dorsal nerve from the vertebra above the offending level often must also be blocked to provide complete pain relief.

At each level, the dorsal ramus provides a medial branch that wraps around the convexity of the articular pillar of its respective vertebra. This location is constant for the C3-C7 nerves and allows a simplified approach to treatment of cervical facet syndrome.

TECHNIQUE Radiofrequency lesioning of the cervical facet joints by disruption of the corresponding medial branches of the affected joints is the preferred route for denervating the cervical facet joints. This technique is best performed under fluoroscopic, computed tomographic, or ultrasound guidance.

Posterior Approach The patient is placed in the prone position. Pillows are placed under the chest to allow the cervical spine to be moderately flexed without discomfort to the patient. The forehead is allowed to rest on a folded blanket (Fig. 42-1). To allow proper positioning of the radiofrequency cannula, the fluoroscopy beam is rotated to obtain a lateral view. The center of the neural arch at the targeted level is then identified. After preparation of the skin with antiseptic solution, a skin wheal of local anesthetic is raised at the site of needle insertion. A 22-gauge, 2-inch needle is then inserted using “tunnel vision” to contact bone at the centroid of the neural arch. The fluoroscope beam is then rotated to provide a clear anteroposterior (AP) view, and the waist of the articular pillar is identified. A 22-gauge, 4-mm active-tip radiofrequency needle is then inserted through the skin and directed under AP fluoroscopic guidance toward the needle that was previously placed at the centroid of the neural arch. The needle should be noted to lie at the waist of the vertebra on the AP view, just posterior to the foramen on the foraminal view, and covering the centroid, and therefore in close proximity to the medial branch, in the lateral view (Figs. 42-2, 42-3, and 42-4). After confirmation of proper needle placement, stimulation at 50 Hz is carried out with the patient reporting stimulation between 0.1 and 0.5 V. This should reproduce the patient’s pain pattern, although the quality may not be perceived as identical by the patient. Motor stimulation via the radiofrequency cannula at 2 to 3 V at 2 Hz is increased slowly. There should be no stimulation of the upper extremity at 2 1 2 to 3 times the voltage required for 169

42 CERVICAL FACET NEUROLYSIS: RADIOFREQUENCY LESIONING OF THE CERVICAL MEDIAL BRANCH

169.e1

IAP

SF POSTERIOR

SAP

IAP

B

SF SAP

Figure E42-1 Hemarthrosis in a cervical spine facet joint in a motor vehicle crash fatality. Top, Large overview of the joint, inferior articular process (IAP), superior articular process (SAP), synovial fold (SF), and joint space (JS) (Masson-Goldner trichrome, ×1.25). Bottom, Close-up of shaded area illustrating bleeding into the joint space (B) (Masson-Goldner trichrome, ×4). (From Uhrenholt L, Charles AV, Hauge E, et al: Pathoanatomy of the lower cervical spine facet joints in motor vehicle crash fatalities. J Forensic Leg Med 16[5]:253-260, 2009.)

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Figure 42-1 For radiofrequency lesioning of the medial branch of the cervical spine, the patient is placed in the prone position. Pillows are placed under the chest to allow the cervical spine to be moderately flexed without discomfort to the patient. The forehead is allowed to rest on a folded blanket. the patient to perceive sensory stimulation. If motor stimulation of the upper extremity is identified, the radiofrequency needle must be repositioned away from the cervical nerve root. After the injection of local anesthetic, a radiofrequency lesion is then made at 80°C for 60 to 90 seconds. The needle is then repositioned superiorly or inferiorly 2 to 3 mm, and a second lesion is made. This

technique is repeated at each targeted level, with care taken to complete trial stimulation each time the radiofrequency electrode is repositioned.

Foraminal Approach The patient is placed in the supine position. The skin overlying the anterior and ipsilateral region above the

C4

Superior articular process

C5

Medial branch of posterior primary ramus

Anterior ramus

C6

Figure 42-2

Proper needle placement for radiofrequency lesioning of the medial branch of the cervical spine. The needle should be noted to lie at the waist of the vertebra on the anteroposterior view, just posterior to the foramen on the foraminal view, and covering the centroid, and therefore in close proximity to the medial branch, in the lateral view.

C7

42 CERVICAL FACET NEUROLYSIS: RADIOFREQUENCY LESIONING OF THE CERVICAL MEDIAL BRANCH

171

Spinous process

Medial branch of posterior primary ramus Lateral branch of posterior primary ramus

Posterior tubercle Anterior ramus Anterior tubercle

Figure 42-3

Vertebral body Cross-sectional view of proper needle placement for radiofrequency lesioning of the medial branch of the cervical spine.

target vertebra is prepared with antiseptic solution. A lateral image is obtained with the fluoroscope, and the fluoroscope tube is then rotated to demonstrate the foramen in its greatest diameter. The fluoroscope beam is then moved caudally until the foramen is seen in its maximal dimension, which will place the beam parallel to the exiting nerve root (Fig. 42-5). The

Figure 42-5 Figure 42-4 Lateral fluoroscopic image demonstrating the needles in proper position for radiofrequency lesioning of the medial branch.

A lateral image is obtained with the fluoroscope and the fluoroscope tube is then rotated to demonstrate the foramen in its greatest diameter. The fluoroscope beam is then moved caudally until the foramen is seen in its maximal dimension, which will place the beam parallel to the exiting nerve root. (Red stars mark the targets for needle tip placement.)

targeted level is again confirmed, and the skin is anesthetized with local anesthetic over an area two times the width of the neural arch to a point even with the lower third of the foramen. A radiofrequency cannula is then inserted and advanced so as to contact bone one fourth to one third of the distance between the foramen and the posterior border of the articular pillar. An AP view will confirm that the cannula tip lies at the waist of the articular column. After confirmation of proper needle placement, stimulation at 50 Hz is carried out, with the patient reporting stimulation between 0.1 and 0.5 V. This should reproduce the patient’s pain pattern, although the quality may not be perceived as identical by the patient. Motor stimulation via the radiofrequency cannula at 2 to 3 V at 2 Hz is increased slowly. There should be no stimulation of the upper extremity at 2 1 2 to 3 times the voltage required for the patient to perceive sensory stimulation. If motor stimulation of the upper extremity is identified, the radiofrequency needle must be repositioned away from the cervical nerve root. After the injection of local anesthetic, a radiofrequency lesion is then made at 80°C for 60 to 90 seconds. The needle is then repositioned superiorly or inferiorly 2 to 3 mm, and a second lesion is made. This

technique is repeated at each targeted level, with care taken to complete trial stimulation each time the radiofrequency electrode is repositioned.

SIDE EFFECTS AND COMPLICATIONS The proximity to the spinal cord, exiting nerve roots, and vascular structures makes it imperative that this procedure be carried out only by those well versed in the regional anatomy and experienced in performing interventional pain management procedures. The proximity to the vertebral artery, combined with the vascular nature of this anatomic region, makes the potential for intravascular injection or trauma to the vessel high. Even the injection of small amounts of local anesthetic into the vertebral arteries will result in seizures. Given the proximity of the brain and brain stem, ataxia due to vascular uptake of local anesthetic is not an uncommon occurrence after cervical facet block. Many patients also complain of a transient increase in headache and cervicalgia after radiofrequency lesioning of these structures, and the routine injection of methylprednisolone or other steroids during or after radiofrequency lesioning may decrease the frequency of this annoying side effect.

Clinical Pearls Radiofrequency lesioning of the cervical medial branches of the primary posterior rami is being used more frequently to provide long-lasting relief of pain emanating from the cervical facet joints. Appropriate diagnostic testing, optimization of conservative therapy, and careful patient selection will help decrease the potential for suboptimal results, and careful attention to needle placement and rigid adherence to the rule of repeat trial stimulation every time the needle is repositioned will markedly decrease the incidence of complications associated with this technique.

Radiofrequency lesioning of the C2 dorsal root ganglion (at the atlantoaxial joint) of the primary posterior rami may be combined with radiofrequency lesioning of the atlantoaxial joint when treating pain in the previously mentioned areas. Many pain management specialists believe that these techniques are currently underused in the treatment of postwhiplash cervicalgia and cervicogenic headaches. These specialists believe that both techniques should be considered when cervical epidural nerve blocks and occipital nerve blocks fail to provide palliation of these headache and neck pain syndromes.

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C H A P T E R

43

Cervical Facet Block: Intra-articular Technique CPT-2015 Code First Joint Second Joint Third and Additional Joint

Relative Value Units 64490 64491 64492

First Joint Second Joint Third Plus Any Additional Joint

10 10 10

43

CERVICAL FACET BLOCK: INTRA-ARTICULAR TECHNIQUE

ABSTRACT

KEY WORDS

The cervical facet joints are formed by the articulations of the superior and inferior articular facets of adjacent vertebrae. Each facet joint receives innervation from two spinal levels. Each joint receives fibers from the dorsal ramus at the same level as the vertebra as well as fibers from the dorsal ramus of the vertebra above. This fact has clinical import in that it provides an explanation for the ill-defined nature of facet-mediated pain and also explains why the dorsal nerve from the vertebra above the offending level often must also be blocked to provide complete pain relief. At each level, the dorsal ramus provides a medial branch that wraps around the convexity of the articular pillar of its respective vertebra. This location is constant for the C4-C7 nerves and allows a simplified approach to treatment of cervical facet syndrome. Cervical facet block using the medial branch technique is useful in the diagnosis and treatment of painful conditions involving trauma, arthritis, or inflammation of the cervical facet joints.

arthritis cervical facet block cervical facet joint cervical medial branch block cervicalgia

172.e1

headache medial branch neck pain radiofrequency lesioning zygapophysial joint

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CERVICAL FACET BLOCK: INTRA-ARTICULAR TECHNIQUE

INDICATIONS Cervical facet block using the intra-articular technique is indicated primarily as a diagnostic maneuver to prove that a specific facet joint is in fact the source of pain. The medial branch technique of facet block is suitable for most clinical applications, including the treatment of painful conditions involving trauma, arthritis, or inflammation of the cervical facet joints. These problems may manifest clinically as neck pain, suboccipital headache, and occasionally shoulder and supraclavicular pain.

CLINICALLY RELEVANT ANATOMY The cervical facet joints are formed by the articulations of the superior and inferior articular facets of adjacent vertebrae. Except for the atlanto-occipital and atlantoaxial joints, the cervical facet joints are true joints in that they are lined with synovium and possess a true joint capsule. This capsule is richly innervated, which supports the notion of the facet joint as a pain generator. The cervical facet joint is susceptible to arthritic changes and trauma caused by acceleration-deceleration injuries. Such damage to the joint results in pain secondary to synovial joint inflammation and adhesions. Each facet joint receives innervation from two spinal levels. Each joint receives fibers from the dorsal ramus at the same level as the vertebra as well as fibers from the

dorsal ramus of the vertebra above. This fact has clinical import in that it provides an explanation for the illdefined nature of facet-mediated pain and explains why the branch of the dorsal ramus arising above the offending level often must also be blocked to provide complete pain relief (Fig. 43-1). At each level, the dorsal ramus provides a medial branch that wraps around the convexity of the articular pillar of its respective vertebra and provides innervation to the facet joint.

TECHNIQUE Landmark and Fluoroscopically Guided Techniques Cervical facet block using the intra-articular technique may be performed blind or under fluoroscopic guidance. The patient is placed in the prone position (Fig. 43-2). Pillows are placed under the chest to allow the cervical spine to be moderately flexed without discomfort to the patient. The forehead is allowed to rest on a folded blanket. Landmark Technique If a blind technique is used, the spinous process at the level to be blocked is identified by palpation. A point two spinal levels lower and 2.5 cm lateral to the spinous process is then identified as the site of needle insertion. Three milliliters of preservative-free local anesthetic is drawn up in a 5-mL sterile syringe. After preparation of the skin with antiseptic solution, a skin wheal of local

C2–3

C3–4

C4–5

C5–6

C6–7

Figure 43-1

Pattern of distribution of cervical facet joint pain. (From King W, Borowczyk JM: Zygapophysial joint pain: procedures for diagnosis and treatment. In Lennard TA, Walkowski SA, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011, pp 357-389.)

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Figure 43-2 The patient is placed in the prone position. Pillows are placed under the chest to allow the cervical spine to be moderately flexed without discomfort to the patient. anesthetic is raised at the site of needle insertion. When the treatment is for pain thought to be secondary to an inflammatory process, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. An 18-gauge, 1-inch needle is inserted through the skin and into the subcutaneous tissues at the previously identified insertion site to serve as an introducer. The introducer needle is then repositioned with a superior and ventral trajectory, pointing directly toward the inferior margin of the facet joint at the level to be blocked. The angle of the needle to the skin is about 35 degrees. A 25-gauge, 31 2-inch styletted spinal needle is then inserted through the 18-gauge introducer and directed toward the articular pillar just below the joint to be blocked. Care

must be taken to be sure the trajectory of the needle does not drift either laterally or medially. Medial drift can allow the needle to enter the epidural, subdural, or subarachnoid space and to traumatize the dorsal root or spinal cord. Lateral drift can allow the needle to pass beyond the lateral border of the articular pillar and traumatize the vertebral artery or exiting nerve roots. After bony contact is made, the depth of the contact is noted, and the spinal needle is withdrawn. The introducer needle is then redirected slightly more superiorly. The spinal needle is then advanced through the introducer needle until it impinges on the bone of the articular pillar. This maneuver is repeated until the spinal needle slides into the facet joint (Fig. 43-3). A pop is often felt as the needle slides into the joint cavity. After the needle is felt to be in satisfactory position, the stylet is removed from the 25-gauge spinal needle, and the hub is observed for blood or cerebrospinal fluid. If neither is present, gentle aspiration of the needle is carried out. If the aspiration results are negative, 1 mL of solution is injected slowly through the spinal needle. Rapid or forceful injection may rupture the joint capsule and exacerbate the patient’s pain. Fluoroscopically Guided Technique If fluoroscopy is used, the beam is rotated in a sagittal plane from anterior to posterior position, which allows identification and visualization of the articular pillars of the respective vertebrae and the adjacent facet joints. After preparation of the skin with antiseptic solution, a skin wheal of local anesthetic is raised at the site of needle insertion. An 18-gauge, 1-inch needle is inserted at the insertion site to serve as an introducer. The fluoroscope beam is aimed directly through the introducer needle,

Facet joint

C3

C4

C5

C6

C7

Figure 43-3 Proper needle trajectory and placement for cervical intra-articular facet block using the landmark technique.

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CERVICAL FACET BLOCK: INTRA-ARTICULAR TECHNIQUE

which will appear as a small point on the fluoroscopy screen. The introducer needle is then repositioned under fluoroscopic guidance until this small point is visualized pointing directly toward the inferior aspect of the facet joint to be blocked. A total of 5 mL of contrast medium suitable for intrathecal use is drawn up in a sterile 12-mL syringe. Then 2 mL of preservative-free local anesthetic is drawn up in a separate 5-mL sterile syringe. When the treatment is for pain thought to be secondary to an inflammatory process, a total of 80 mg of depot-steroid is added to the local

A

175

anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. A 25-gauge, 31 2-inch styletted spinal needle is then inserted through the 18-gauge introducer and directed toward the articular pillar just below the joint to be blocked. After bony contact is made, the spinal needle is withdrawn, and the introducer needle is repositioned superiorly, aiming toward the facet joint itself. The 25-gauge spinal needle is then readvanced through the introducer needle until it enters the target joint (Fig. 43-4, A and B; Fig. 43-5).

B

C Figure 43-4

Cervical facet joint pain on the right side. Right C4-C5 facet block. A, Lateral radiograph after insertion of the needle (N) into the right C4-C5 facet joint (FJ) using a near-direct lateral approach. P, C4 pedicle. B, Anteroposterior (AP) radiograph confirming that the needle tip (arrow) is in the facet joint from a right lateral approach. Articular pillars of C4 and C5 are labeled. C, Lateral arthrogram with the needle in the C4-C5 facet joint. (From Fenton DS, Czervionke LF: Image-Guided Spine Intervention. Philadelphia, Saunders, 2003.)

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Figure 43-5

Lateral fluoroscopic image showing contrast medium within the C2-C3 facet joint. (From Lennard TA, Walkowski DO, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011.)

After confirmation of needle placement by biplanar fluoroscopy, the stylet is removed from the 25-gauge spinal needle, and the hub is observed for blood or cerebrospinal fluid. If neither is present, gentle aspiration of the needle is carried out. If the aspiration results are negative, 1 mL of contrast medium is slowly injected under fluoroscopic guidance to reconfirm needle placement (see Fig. 43-4, C and D; Fig. 43-5). After correct needle placement is confirmed, 1 mL of local anesthetic with or without steroid is slowly injected through the spinal needle. Rapid or forceful injection may rupture the joint capsule and exacerbate the patient’s pain.

Ultrasound-Guided Technique If ultrasound guidance is used, the patient is placed in the prone position (see Fig. 43-2). Pillows are placed under the chest to allow the cervical spine to be moderately flexed without discomfort to the patient. The forehead is allowed to rest on a folded blanket. A total of 0.25 mL of contrast medium suitable for intrathecal use is drawn up in a sterile 3-mL syringe. Then 0.25 mL of preservativefree local anesthetic is drawn up in a separate 3-mL sterile syringe. When the treatment is for pain thought to be secondary to an inflammatory process, a total of 40 mg of depot-steroid is added to the local anesthetic with the first block, and 20 mg of depot-steroid is added with subsequent blocks. The midline of the cervical spine is identified by palpation of the spinous processes (see Fig. 43-3). After preparation of the skin with antiseptic solution, a high-frequency linear ultrasound transducer is placed in a longitudinal plane at the level of the occiput and the spinous processes starting at C1 are identified (Fig. 43-6). C1 has only a vestigial spinous process compared with the remaining cervical vertebrae, and the more pronounced bifid spinous process of C2 can aid the clinician when counting the

Figure 43-6 A high-frequency linear ultrasound transducer is placed in a longitudinal plane at the level of the occiput. cervical vertebra to identify the facet joint to be blocked (Figs. 43-7 and 43-8). After the proper level has been identified, the ultrasound transducer is slowly moved laterally until the articular pillars of the facet joints appear with their characteristic wavy or sawtooth appearance (Fig. 43-9). The transducer is then rocked slightly laterally or medially until the facet joint, which appears as an anechoic gap between the two hyperechoic echoes of the superior and inferior articular processes, is clearly visualized (Fig. 43-10). A 31 2-inch styletted spinal needle is then inserted beneath the caudal end of the ultrasound transducer using an in-plane approach and is advanced with a caudad to cephalad trajectory into the facet joint.

C0 C1

C2

C3

Figure 43-7 Longitudinal ultrasound image showing the spinous processes of the upper cervical spine. Note the vestigial spinous process of C1 and the more pronounced bifid spinous process of C2.

43

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CERVICAL FACET BLOCK: INTRA-ARTICULAR TECHNIQUE

Bifid spinous process

Figure 43-8

Classic ultrasound appearance of the bifid spinous process of C2.

C4 C5

C6

C7

T1

Figure 43-9 Characteristic wavy sawtooth appearance of the articular processes of the cervical spine. After gentle aspiration, 0.25 to 0.5 mL of solution is injected with care being taken to avoid the vertebral artery, which is located anterior to the facet joints. The needle is removed and pressure is placed on the injection site to avoid hematoma formation.

SIDE EFFECTS AND COMPLICATIONS C0 C1

C2

C3

Figure 43-10 Longitudinal ultrasound image showing the hyperechoic “hills,” which are the articular processes, and the “valleys,” which are the hyperechoic spaces between two adjacent facet joints. The valleys contain the medial branches.

The proximity to the spinal cord and exiting nerve roots makes it imperative that this procedure be carried out only by those well versed in the regional anatomy and experienced in performing interventional pain management procedures. The proximity to the vertebral artery, combined with the vascular nature of this anatomic region, makes the potential for intravascular injection high. Even small amounts of local anesthetic injected into the vertebral arteries will result in seizures. Given the proximity of the brain and brain stem, ataxia due to vascular uptake of local anesthetic is not an uncommon occurrence after cervical facet block. Many patients also complain of a transient increase in headache and cervicalgia after injection of the joint.

Clinical Pearls Cervical facet block using the medial branch approach is the preferred technique for treatment of cervical facet syndrome. Although intra-articular placement of the needle into the facet joint is technically feasible, such maneuvers add nothing to the efficacy of the procedure unless specific diagnostic information about that specific joint is required and in fact may increase the rate of complications. Cervical facet block is often combined with atlantooccipital block when treating pain in the previously mentioned areas. Although the atlanto-occipital joint is not a true facet

joint in the anatomic sense of the word, the atlanto-occipital joint block technique is analogous to the facet joint block technique used commonly by pain practitioners and may be viewed as such. Many pain management specialists believe that these techniques are currently underused in the treatment of postwhiplash cervicalgia and cervicogenic headaches. These specialists believe that both techniques should be considered when cervical epidural nerve blocks and occipital nerve blocks fail to provide palliation of these headache and neck pain syndromes.

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Cervical Epidural Block: Translaminar Approach CPT-2015 Code Local Anesthetic/Narcotic Steroid Neurolytic

62310 62310 62281

Relative Value Units Local Anesthetic Steroid Neurolytic

10 10 20

treatment with epidurally administered local anesthetics, steroids, or opioids (Fig. 44-1). Additionally, this technique is of value in patients with acute vascular insufficiency of the upper extremities secondary to vasospastic and vaso-occlusive disease, including frostbite and ergotamine toxicity. There is increasing evidence that the prophylactic or preemptive use of epidural nerve blocks in patients scheduled to undergo limb amputations for ischemia decreases the incidence of phantom limb pain. The administration of local anesthetics, steroids, or both via the cervical approach to the epidural space is

INDICATIONS In addition to having a limited number of applications for surgical anesthesia, cervical epidural nerve block with local anesthetics can be used as a diagnostic tool when differential neural blockade is performed on an anatomic basis in the evaluation of head, neck, face, shoulder, and upper extremity pain. If destruction of the cervical nerve roots is being considered, this technique can be used in a prognostic manner to indicate the degree of motor and sensory impairment that the patient may experience. Cervical epidural nerve block with local anesthetics, opioids, or both may be used for palliation in acute pain emergencies during the wait for pharmacologic, surgical, or antiblastic methods to take effect. This technique is useful in the management of postoperative pain as well as pain secondary to trauma. The pain of acute herpes zoster and cancer-related pain is also amenable to

Figure 44-1 Herpes zoster vesicles along the ulnar aspect of the wrist. (From Athwal GS, Bartsich SA, Weiland AJ: Herpes zoster in the ulnar nerve distribution. J Hand Surg Br 30[4]:355-357, 2005.)

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CERVICAL EPIDURAL BLOCK: TRANSLAMINAR APPROACH

ABSTRACT

KEY WORDS

The superior boundary of the cervical epidural space is the fusion of the periosteal and spinal layers of dura at the foramen magnum. The epidural space continues inferiorly to the sacrococcygeal membrane. The cervical epidural space is bounded anteriorly by the posterior longitudinal ligament and posteriorly by the vertebral laminae and the ligamentum flavum. The vertebral pedicles and intervertebral foramina form the lateral limits of the epidural space. The cervical epidural space is 3 to 4 mm at the C7-T1 interspace with the cervical spine flexed. The cervical epidural space contains fat, veins, arteries, lymphatics, and connective tissue. Cervical epidural block can be used for surgical anesthesia as well as for diagnostic, prognostic, and therapeutic purposes.

acute herpes zoster cancer pain cervical epidural nerve block cervical radiculopathy epidural abscess interlaminar

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ligamentum flavum reflex sympathetic dystrophy subdural space tension-type headache translaminar

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CERVICAL EPIDURAL BLOCK: TRANSLAMINAR APPROACH

179

spine. The long-term epidural administration of opioids has become a mainstay in the palliation of cancer-related pain.

CLINICALLY RELEVANT ANATOMY The superior boundary of the cervical epidural space is the fusion of the periosteal and spinal layers of dura at the foramen magnum. The epidural space continues inferiorly to the sacrococcygeal membrane. The cervical epidural space is bounded anteriorly by the posterior longitudinal ligament and posteriorly by the vertebral laminae and the ligamentum flavum (Fig. 44-3). The vertebral pedicles and intervertebral foramina form the lateral limits of the epidural space (Fig. 44-4). The cervical epidural space is 3 to 4 mm at the C7-T1 interspace with the cervical spine flexed. The cervical epidural space contains fat, veins, arteries, lymphatics, and connective tissue. When cervical epidural block in the midline is performed, after the skin and subcutaneous tissues are traversed, the styletted epidural needle will impinge on the ligamentum nuchae, which runs vertically between the apices of the cervical spinous processes. The interspinous ligament, which runs obliquely between the spinous processes, is encountered next, offering additional resistance to needle advancement (Fig. 44-5). This ligament is dense enough to hold a needle in position even when the needle is released. Because the interspinous ligament is contiguous with the ligamentum flavum, the pain management specialist may perceive a false loss of resistance when the needle tip enters the space between the interspinous ligament and the ligamentum flavum. This phenomenon is more pronounced in the cervical region than in the lumbar region because the ligaments in the cervical region are less well defined. A significant increase in resistance to needle advancement signals that the needle tip is impinging on the dense ligamentum flavum. Because the ligament is made up almost entirely of elastin fibers, there is a continued increase in resistance as the needle traverses the ligamentum flavum owing to the drag of the ligament on the needle. A sudden loss of resistance occurs as the needle tip enters the epidural space. There should be essentially no resistance to drugs injected into the normal epidural space.

Figure 44-2 T1-weighted magnetic resonance image showing relation of a metastatic spinal tumor to the cervical spinal cord. (From Molina CA, Gokaslan ZL, Sciubba DM: Diagnosis and management of metastatic cervical spine tumors. Orthop Clin North Am 43[1]:75-87, 2012.) useful in the treatment of a variety of chronic benign pain syndromes, including cervical radiculopathy, cervicalgia, cervical spondylosis, cervical postlaminectomy syndrome, tension-type headache, phantom limb pain, vertebral compression fractures, diabetic polyneuropathy, chemotherapy-related peripheral neuropathy, postherpetic neuralgia, reflex sympathetic dystrophy, and neck and shoulder pain syndromes. The cervical epidural administration of local anesthetics in combination with steroids, opioids, or both is also useful in the palliation of cancer-related pain of the head, face, neck, spine, shoulder, upper extremity, and upper trunk (Fig. 44-2). This technique has been especially successful in the relief of pain secondary to metastatic disease of the

Int. jugular v. Common carotid a. Spinal arterial branch Anterior radicular a. Anterior spinal a. Posterior radicular a.

C6

Vertebral a. Cervical nerve root Superior articular process Spinal cord Epidural space Ligamentum flavum Spinous process

Figure 44-3

Axial view at the C6 vertebral level demonstrating the relationship of the ligamentum flavum to the cervical epidural space. a., Artery; Int., internal; v., vein.

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TECHNIQUE Landmark and Fluoroscopically Guided Technique

T

Figure 44-4

Sagittal T1-weighted magnetic resonance image of the cervical spine. The C6-T3 vertebral bodies are indicated with the numerals 6, 7, 1, 2, and 3, respectively. The epidural spaces in between these vertebrae are noted with small black arrows. In a patient weighing 59 kg, the distances from the skin to the apex of the epidural spaces were 42 mm, 45 mm, 37 mm, and 32 mm, respectively, from top to bottom (vertical scale equals 50 mm). Large black arrow points to the spinal cord. T, Tongue. (From Aldrete JA, Mushin AU, Zapata JC, et al: Skin to cervical epidural space distances as read from magnetic resonance imaging films: consideration of the “hump pad.” J Clin Anesth 10[4]:309-313, 1998.)

Cervical epidural nerve block may be carried out with the patient in the sitting, lateral, or prone position; the sitting position is favored for landmark-guided procedures because of the simplicity of patient positioning compared with the lateral or prone position. After the patient is placed in an optimal sitting position with the cervical spine flexed and the forehead placed on a padded bedside table, the skin is prepared with an antiseptic solution. At the C5-C6 or C6-C7 interspace, the operator’s middle and index fingers are placed on each side of the spinous processes. The position of the interspace is reconfirmed with palpation using a rocking motion in the superior and inferior planes (Fig. 44-6). The midline of the selected interspace is identified by palpating the spinous processes above and below the interspace using a lateral rocking motion to ensure that the needle entry site is exactly in the midline. One milliliter of local anesthetic is used to infiltrate the skin, subcutaneous tissues, and supraspinous and interspinous ligaments at the midline. For experienced practitioners, a 25-gauge, 2-inch needle is preferred for this technique. For less experienced practitioners, a longer, larger, blunter needle such as an 18- or

Ligamentum nuchae

C2

Interspinous ligament

C3

Ligamentum flavum

C4

C5 Epidural space C6 Supraspinous ligament C7 Spinal dura mater

Figure 44-5

When cervical epidural block in the midline is performed, after the skin and subcutaneous tissues are traversed, the styletted epidural needle will impinge first on the ligamentum nuchae, which runs vertically between the apices of the cervical spinous processes; next on the interspinous ligament, which runs obliquely between the spinous processes; and finally on the ligamentum flavum, before the cervical epidural space is entered.

44

Figure 44-6

CERVICAL EPIDURAL BLOCK: TRANSLAMINAR APPROACH

To identify the vertebral interspace when performing cervical epidural block, the operator places the middle and index fingers on either side of the spinous processes. The position of the interspace is reconfirmed with palpation using a rocking motion in the superior and inferior planes. The midline of the selected interspace is identified by palpating the spinous processes above and below the interspace using a lateral rocking motion to ensure that the needle entry site is exactly in the midline.

181

20-gauge, 31 2-inch Hustead needle may be used. The needle chosen is inserted exactly in the midline in the previously anesthetized area through the ligamentum nuchae into the interspinous ligament (Fig. 44-7; see also Fig. 44-5). A right-handed physician holds the epidural needle firmly at the hub with his or her left thumb and index finger. The left hand is placed firmly against the patient’s neck to ensure against uncontrolled needle movements should the patient unexpectedly move (Fig. 44-8). A syringe containing either preservative-free saline or the intended injectate of local anesthetic, narcotic, or steroid is attached with constant pressure applied to the plunger of the syringe with the thumb of the right hand; then the needle and syringe are continuously advanced in a slow and deliberate manner with the left hand. As soon as the needle bevel passes through the ligamentum flavum and enters the epidural space, there will be a sudden loss of resistance to injection, and the plunger will effortlessly surge forward (Fig. 44-9). If there is uncertainty about needle position, the syringe is gently removed from the needle and an air or saline acceptance test is carried out by injecting 0.5 to 1 mL of air or sterile preservative-free saline with a well-lubricated sterile glass syringe to help confirm that the needle is within the epidural space. The force required for injection should not exceed that necessary to overcome the resistance of the needle. Any significant pain or sudden increase in resistance during injection suggests incorrect needle placement, and the practitioner should stop injecting immediately and reassess the position of the needle. When satisfactory needle position is confirmed, a syringe containing 5 to 7 mL of the solution to be injected

Needle in supraspinous ligament / ligamentum nuchae Spinous process Needle in interspinous ligament Needle in ligamentum flavum Needle in epidural space Sup. articular process Post. ramus

Ant. ramus

Figure 44-7

For cervical epidural block using the translaminar approach, the needle is inserted exactly in the midline until it impinges on the ligamentum flavum. a., Artery; Ant., anterior; Post., posterior; Sup., superior.

Vertebral body

Vertebral a. Spinal ganglion

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Figure 44-8 A right-handed physician holds the epidural needle firmly at the hub with his or her left thumb and index finger. The left hand is placed firmly against the patient’s neck to ensure against uncontrolled needle movements should the patient unexpectedly move.

Figure 44-9

A syringe containing either preservative-free saline or the intended injectate of local anesthetic, narcotic, or steroid, is attached with constant pressure applied to the plunger of the syringe with the thumb of the right hand; then the needle and syringe are continuously advanced in a slow and deliberate manner with the left hand. As soon as the needle bevel passes through the ligamentum flavum and enters the epidural space, there will be a sudden loss of resistance to injection, and the plunger will effortlessly surge forward.

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CERVICAL EPIDURAL BLOCK: TRANSLAMINAR APPROACH

is carefully attached to the needle. Gentle aspiration is carried out to identify cerebrospinal fluid or blood. If cerebrospinal fluid is aspirated, the epidural block may be repeated at a different interspace. In this situation, drug dosages should be adjusted accordingly, because subarachnoid migration of drugs through the dural rent can occur. If aspiration of blood occurs, the needle should be rotated slightly and the aspiration test repeated. If no blood is present, incremental doses of local anesthetic and other drugs may be administered while the patient is monitored carefully for signs of local anesthetic toxicity. Fluoroscopy is useful if surface landmarks are difficult to palpate because of patient size or previous surgery (Fig. 44-10). A small amount of contrast agent may be injected through the needle to confirm epidural placement (Fig. 44-11). For diagnostic and prognostic blocks, 1.0% preservativefree lidocaine is a suitable local anesthetic. For therapeutic blocks, 0.25% preservative-free bupivacaine in combination with 80 mg of methylprednisolone is injected. Subsequent nerve blocks are carried out in a similar manner, with 40 mg of methylprednisolone substituted for the initial 80-mg dose. Daily cervical epidural nerve blocks with local anesthetic or steroid may be required to treat the previously mentioned acute painful conditions. Chronic conditions such as cervical radiculopathy, tension-type headaches, and diabetic polyneuropathy are treated on an every-other-day to once-a-week basis or as the clinical situation dictates. If the cervical epidural route is chosen for administration of opioids, 0.5 mg of preservative-free morphine sulfate formulated for epidural use is a reasonable initial dose in opioid-tolerant patients. More lipid-soluble opioids such as fentanyl must be delivered by continuous infusion via a cervical epidural catheter. An epidural catheter may be placed into the cervical epidural space through a Hustead needle to allow continuous infusions.

Ultrasound-Guided Technique Ultrasound-guided cervical epidural block can be carried out by placing the patient in the prone position with the patient’s abdomen resting on a thin pillow. A total of 5 mL of local anesthetic suitable for epidural administration is drawn up in a 12-mL sterile syringe. If the painful condition being treated is thought to have an inflammatory component, 40 mg to 80 mg of depot-steroid is added to the local anesthetic. The midline of the cervical spine is identified by palpation of the spinous processes (Fig. E44-1). After preparation of the skin with antiseptic solution, a high-frequency linear ultrasound transducer is placed in a longitudinal plane at the level of the occiput and the spinous processes starting at C1 are identified (Fig. 44-12). C1 has only a vestigial spinous process compared with the remaining cervical vertebrae, and the more pronounced bifid spinous process of C2 can aid the clinician when counting the cervical vertebra to identify the facet joint to be blocked (Figs. 44-13 and 44-14). After the proper level has been identified, the ultrasound transducer is slowly moved laterally until the articular pillars of the facet joints appear with their characteristic wavy or sawtooth appearance (Fig. 44-15).

183

The longitudinally oriented ultrasound transducer is then slowly tilted to angle the ultrasound beam with a lateral to medial oblique trajectory toward the midline. The laminae of successive cervical vertebrae will appear as a series of hyperechoic curvilinear lines with an acoustic shadow beneath each one (Fig. 44-16). The interlaminar spaces will appear as gaps between each successive vertebra, providing an acoustic window that will allow visualization of the ligamentum flavum, epidural space, and posterior dura. In some patients, making minor adjustments to the position of the ultrasound transducer will allow the ligamentum flavum and posterior dura to be distinguished as two distinct hyperechoic linear structures with a hyperechoic epidural space in between. In other patients, these structures simply appear as a single hyperechoic line, which is known as the posterior complex (see Fig. 44-16). After the interlaminar space is identified, the skin is prepared with antiseptic solution and a 22-gauge, 31 2inch needle suitable for epidural use is inserted through the skin at the middle of the lateral aspect of the longitudinally placed ultrasound transducer using an out-ofplane approach. While an assistant holds and adjusts the ultrasound transducer, the clinician advances the needle under real-time ultrasound guidance with an oblique lateral to medial trajectory using a loss-of-resistance technique until the needle tip rests within the epidural space. After gentle aspiration, 5 mL of solution is injected. The needle is removed and pressure is placed on the injection site to avoid hematoma formation.

SIDE EFFECTS AND COMPLICATIONS Because of the potential for hematogenous spread via Batson’s plexus, local infection and sepsis represent absolute contraindications to use of the cervical approach to the epidural space. Unlike with the caudal approach to the epidural space, anticoagulant therapy and coagulopathy are absolute contraindications to cervical epidural nerve block because of the risk of epidural hematoma. Inadvertent dural puncture during cervical epidural nerve block should occur less than 0.5% of the time. Failure to recognize inadvertent dural puncture can result in immediate total spinal anesthesia with associated loss of consciousness, hypotension, and apnea. If epidural doses of opioids are accidentally injected into the subarachnoid space, significant respiratory and central nervous system depression will result. It is also possible to inadvertently place a needle or catheter intended for the epidural space into the subdural space. If subdural placement is unrecognized and epidural doses of local anesthetics are administered, the signs and symptoms are similar to those of massive subarachnoid injection, although the resulting motor and sensory block may be spotty. The cervical epidural space is highly vascular. Intravenous placement of the epidural needle occurs in about 0.5% to 1% of patients undergoing cervical epidural anesthesia. The incidence of this complication is increased in patients with distended epidural veins, such as parturient women and patients with a large intra-abdominal tumor mass. If the misplacement is unrecognized and local

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Figure E44-1

CERVICAL EPIDURAL BLOCK: TRANSLAMINAR APPROACH

The midline of the cervical spine is identified by palpation of the spinous processes.

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B

A

C Figure 44-10

D

Cervical translaminar epidural approach. A, With C-arm fluoroscopy, a midline anteroposterior (AP) approach at C7-T1 is established with a 22-gauge Tuohy needle using steep cranial-caudal angulation (arrow). B, In the lateral projection with the patient in the swimmer’s position, the Tuohy needle can be seen just beneath the C7 spinous process (arrow). The slight curve in the lower margin of the spinous process helps identify the approximate location of the edge of the ligamentum flavum and the posterior epidural fat (arrowhead). C, When loss of pressure resistance indicates that the epidural space has been entered, confirmation is made with further contrast injection observed in the lateral position (arrowheads). D, Epidural injection is confirmed in the AP projection (arrowheads). (From Eckel TS, Bartynski WS: Epidural steroid injections and selective nerve root blocks. Tech Vasc Interv Radiol 12[1]:11-21, 2009.)

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185

Figure 44-13

Longitudinal ultrasound image demonstrating the spinous processes of the upper cervical spine.

Figure 44-11 Oblique view following injection of an additional 1.5 mL of nonionic contrast material demonstrates additional inferior flow as well as flow into the more superior cervical spinal canal (arrow). (From Renfrew DL: Atlas of Spine Injection, 4th ed. Philadelphia, Saunders, 2004, p 52.) anesthetic is injected directly into an epidural vein, significant local anesthetic toxicity will result. Needle trauma to the epidural veins may result in selflimited bleeding, which may cause postprocedure pain. Uncontrolled bleeding into the epidural space may result in compression of the spinal cord with the rapid development of neurologic deficit. Although significant neurologic deficit secondary to epidural hematoma after cervical

epidural block is exceedingly rare, this devastating complication should be considered whenever there is rapidly developing neurologic deficit after cervical epidural nerve block. Neurologic complications after cervical nerve block are uncommon if proper technique is used. Direct trauma to Bifid spinous process

Figure 44-14 process of C2.

Figure 44-12 Placement of the ultrasound transducer in the longitudinal plane over the spinous processes with the cephalad end of the transducer at the occiput.

Classic ultrasound appearance of the bifid spinous

Figure 44-15 Characteristic wavy sawtooth appearance of the articular processes of the cervical spine.

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Figure 44-16 Longitudinal paramedian sonographic view of the cervical spine showing the articular pillars, lamina (arrow), and ligamentum flavum. (From Shankar H, Zainer CM: Ultrasound guidance for epidural steroid injections. Tech Reg Anesth Pain Manag 13[4]:229235, 2009.)

the spinal cord or nerve roots is usually accompanied by pain. If significant pain occurs during placement of the epidural needle or catheter or during injection, the physician should immediately stop and ascertain the cause of the pain to avoid the possibility of additional neural trauma. Although uncommon, infection in the epidural space remains an ever-present possibility, especially in the immunocompromised patient with acquired immunodeficiency syndrome or cancer (Figs. 44-17 and 44-18). If epidural abscess occurs, emergent surgical drainage to avoid spinal cord compression and irreversible neurologic deficit is usually required. Early detection and treatment of infection is crucial to avoid potentially life-threatening sequelae.

A

B

Interlaminar space

Lamina

Lamina

Lamina

C Figure 44-18

Anterior complex

Anterior complex

Figure 44-17 Longitudinal ultrasound image showing successive lamina, the interlaminar space, the posterior complex, and the spinal cord.

A, Midsagittal T2-weighted magnetic resonance image of the cervical spine showing a high-signal-intensity posterior epidural collection communicating with an extraspinal collection. Note that the communication is made between the posterior arches of C1 and C2. B, Axial T2-weighted image showing the high-signal-intensity collection of both the intraspinal and extraspinal (arrows) component at the C3 level. Note the forward compression of the spinal cord. C, Axial postcontrast T1-weighted image showing peripheral ring–like enhancement of the epidural abscess as well as of the dura itself (arrows). (From Drevelengas A, Chourmouzi D, Grigoriadis C, et al: Cervical paraspinal soft tissue abscess extending to posterior epidural space. Eur J Radiol Extra 47[1]:10-13, 2003.)

Clinical Pearls Cervical epidural nerve block is a safe and effective procedure if careful attention is paid to technique. Failure to accurately identify the midline is the most common reason for difficulty in performing cervical epidural nerve block and increases the risk of complications. It should be noted that the ligamentum flavum is relatively thin in the cervical region compared with the lumbar region. This fact has direct clinical implications in

that the loss of resistance during performance of cervical epidural nerve block is more subtle than during use of the lossof-resistance technique in the lumbar or lower thoracic region. The routine use of sedation or general anesthesia before initiation of cervical epidural nerve block is to be discouraged because it will render the patient unable to provide accurate verbal feedback should needle misplacement occur.

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C H A P T E R

187

45

Cervical Epidural Block: Transforaminal Approach and radiculopathy secondary to cervical disk displacement, neural foraminal stenosis, and perineural fibrosis.

CPT-2015 Code Local Anesthetic Steroid Additional Level

64479 64479 64480

Relative Value Units Local Anesthetic Steroid Each Additional Level

10 10 10

INDICATIONS Cervical epidural injection with local anesthetics, corticosteroid, or both via the transforaminal approach can be used as a diagnostic tool or treatment modality when differential neural blockade is performed on an anatomic basis in the evaluation of head, neck, face, shoulder, and upper extremity pain. If destruction of the cervical nerve roots is being considered, this technique can be used in a prognostic manner to indicate the degree of motor and sensory impairment that the patient may experience. Although the interlaminar approach is more commonly used for routine therapeutic cervical epidural nerve injection, some interventional pain management specialists believe the transforaminal approach to the cervical epidural space is more efficacious in the treatment of painful conditions involving a single nerve root, although the incidence of complications is higher (see Chapter 40 for indications for therapeutic cervical epidural nerve block). Examples of such conditions are cervical radicular pain

CLINICALLY RELEVANT ANATOMY The superior boundary of the cervical epidural space is the fusion of the periosteal and spinal layers of dura at the foramen magnum. The epidural space continues inferiorly to the sacrococcygeal membrane. The cervical epidural space is bounded anteriorly by the posterior longitudinal ligament and posteriorly by the vertebral laminae and the ligamentum flavum. The medial aspect of pedicles and intervertebral foramina form the lateral limits of the epidural space. The cervical epidural space is 3 to 4 mm at the C7-T1 interspace with the cervical spine flexed. The cervical epidural space contains veins, arteries, lymphatics, connective tissue, and a relative paucity of fat compared with the lumbar epidural space (Fig. 45-1). When cervical epidural injections are made using the transforaminal approach, the goal is to place the needle just inside the posterior portion of the neural foramen of the affected nerve root (Figs. 45-2 and 45-3). There should be essentially no resistance to drugs injected into the normal epidural space.

TECHNIQUE Fluoroscopically Guided Technique Cervical epidural injection using the transforaminal approach is carried out with the patient in the supine or lateral position. Although some experienced pain management practitioners perform this technique without radiographic guidance, the use of fluoroscopy is recommended

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CERVICAL EPIDURAL BLOCK: TRANSFORAMINAL APPROACH

ABSTRACT

KEY WORDS

The superior boundary of the cervical epidural space is the fusion of the periosteal and spinal layers of dura at the foramen magnum. The epidural space continues inferiorly to the sacrococcygeal membrane. The cervical epidural space is bounded anteriorly by the posterior longitudinal ligament and posteriorly by the vertebral laminae and the ligamentum flavum. The vertebral pedicles and intervertebral foramina form the lateral limits of the epidural space. The cervical epidural space is 3 to 4 mm at the C7-T1 interspace with the cervical spine flexed. The cervical epidural space contains fat, veins, arteries, lymphatics, and connective tissue. Cervical epidural block can be used for surgical anesthesia as well as for diagnostic, prognostic, and therapeutic purposes.

acute herpes zoster cancer pain cervical epidural nerve block cervical nerve root cervical radiculopathy epidural abscess

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ligamentum flavum reflex sympathetic dystrophy subdural space tension-type headache transforaminal

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Int. jugular v. Common carotid a. Spinal arterial branch

Vertebral a. Cervical nerve root

C6

Superior articular process

Anterior radicular a. Anterior spinal a. Posterior radicular a.

Spinal cord Epidural space Ligamentum flavum Spinous process

Figure 45-1

Axial view at the C6 vertebral level showing the relationship of the ligamentum flavum to the cervical epidural space. a., Artery; Int., internal; v., vein.

to aid in needle placement and helps to avoid placing the needle too deeply into the spinal canal and unintentionally injecting into the spinal cord or misplaced intervascular structures such as the vertebral or segmental arteries. With the patient in the supine or lateral position on the fluoroscopy table, the fluoroscope beam is rotated from a lateral to an anterior oblique position to allow visualization of the affected neural foramen at its largest diameter (Figs. 45-4 and 45-5). The fluoroscope beam is then slowly moved from a cephalad to a more caudad position also to allow visualization of the affected neural foramen. When this is accomplished, the beam should be parallel to the affected nerve root. The skin is then prepared with an antiseptic solution, and a skin wheal of local anesthetic may be placed at a point overlying the posterior aspect of the foramen just over the tip of the superior articular process of the level below the affected neural foramen. This point is about one third of the distance cephalad from the most

posteroinferior aspect of the foramen. A 25-gauge, 2-inch needle is then placed through the previously anesthetized area and advanced until the tip rests against the posteromedial portion of the superior articular process of the targeted neural foramen (Figs. 45-6 through 45-9). Failure to impinge on bone at this point should be of grave concern and may indicate that the needle has passed through the foramen and rests within the substance of the spinal cord. Failure to identify this problem can lead to disastrous results (see “Side Effects and Complications”). After this bony landmark is identified, an anteroposterior fluoroscopic image is obtained to verify that the needle is within the nerve canal and not past the midpoint of the facetal column to avoid placement of the needle within the dura or into the spinal cord. After satisfactory needle position is confirmed and the needle bevel is oriented medially, 0.2 to 0.4 mL of contrast medium suitable for subarachnoid use is gently injected under active fluoroscopy. The contrast agent

VA

VA

F VA G

G

VR DR

Figure 45-2 Anatomic section through lower end of the C5-C6 neural foramen (left) and corresponding computed tomographic scan (right). The spinal nerve exits the foramen anterolaterally (at about a 45-degree angle with respect to the coronal plane) and downward (at about a 10-degree angle with respect to the axial plane). Note the location of the vertebral artery (VA) in relation to the uncinate process and ganglia. DR, Dorsal root; F, fat tissue; G, dorsal root ganglion; VR, ventral root. (From Choi SS, Kim YC: Transforaminal epidural block and cervical epidural block utilizing the transforaminal approach. In Kim DH, Kim YC, Kim KH, editors: Minimally Invasive Percutaneous Spinal Techniques. Philadelphia, Saunders, 2010, pp 124-136.)

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Figure 45-3 Anteroposterior view of left C5 transforaminal epidural steroid injection with contrast medium outlining the proximal and distal nerve root (arrows). (From Leung D, Greenberg JS, Henning PT, et al: Cervical transforaminal epidural injection in the management of a stinger. PM R 4[1]:73-77, 2012.)

Figure 45-4

189

Oblique view of the cervical neural foramina.

Figure 45-5

Oblique fluoroscopic image of the cervical spine showing target points for cervical epidural block using the transforaminal approach. Red circles indicate the target points. A curved block needle should be advanced to the target point using the “tunnel vision” technique. The target point is the posteromedial portion of the foramen, at the division between the caudal and middle third. (From Choi SS, Kim YC: Transforaminal epidural block and cervical epidural block utilizing the transforaminal approach. In Kim DH, Kim YC, Kim KH, editors: Minimally Invasive Percutaneous Spinal Techniques. Philadelphia, Saunders, 2010, pp 124-136.)

Figure 45-6

Oblique view with introducer cannula. (From Raj PP, Lou L, Erdine S, et al: Interventional Pain Management: Image-Guided Procedures, 2nd ed. Philadelphia, Saunders, 2008.)

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C2 C3 C4 C5 C6 C7 C8

Figure 45-7 ral block.

Proper needle position for cervical transforaminal epidu-

Superior articular process

Figure 45-9

Oblique view of the cervical spine in situ demonstrating the proper needle position for cervical transforaminal epidural block.

should be seen to flow into the epidural space and distal along the affected nerve root sheath (Figs. 45-10 and 45-11). The injection of contrast should be stopped immediately if the patient complains of significant pain on injection. After satisfactory flow of contrast is observed and there is no evidence of subdural, subarachnoid, or intravascular spread of contrast, 3 mg of betamethasone with 0.5 mL of 2% or 4% preservative-free lidocaine is slowly injected. Injection of the local anesthetic and steroid should be discontinued if the patient complains of any significant pain on injection. After satisfactory injection of the local anesthetic and steroid, the needle is removed and pressure is placed on the injection site. Dr. Gabor Racz suggests that after injection, the cervical spine should be gently flexed and then gently rotated from side to side to facilitate opening of the neural foramina to reduce epidural pressure. The technique may be repeated at additional levels as a diagnostic or therapeutic maneuver.

Ultrasound-Guided Technique

Figure 45-8 Oblique view of the cervical spine demonstrating the proper needle position for cervical transforaminal epidural block.

For ultrasound-guided cervical epidural block using the transforaminal approach, the patient is placed in the lateral decubitus position. A total of 0.5 mL of local anesthetic is drawn up in a 10-mL sterile syringe for each cervical nerve root to be blocked. If the painful condition being treated is thought to have an inflammatory component, 3 mg of betamethasone is added to the local anesthetic. The cricothyroid notch, which is at the C6 level, is then identified by palpation. After preparation of the skin with antiseptic solution, a high-frequency linear

45

CERVICAL EPIDURAL BLOCK: TRANSFORAMINAL APPROACH

191

Figure 45-12 A high-frequency linear ultrasound transducer is placed in a transverse plane at the level of C6.

Figure 45-10

Typical contrast pattern for right selective C5-C6 transforaminal block. (From Tiso RL, Cutler T, Catania JA, et al: Adverse central nervous system sequelae after selective transforaminal block: the role of corticosteroids. Spine J 4[4]:468-474, 2004.)

ultrasound transducer is placed in a transverse plane at the level of C6 (Fig. 45-12). A transverse ultrasound image is obtained, and the anterior and posterior tubercles of the transverse process are identified. These tubercles have been described as a two-humped camel. The cervical nerve root lies between the two humps (Fig. 45-13). Because the C6 vertebral body can be easily identified by its characteristic camel-humped anterior tubercle

A Figure 45-11

(which is known as Chassaignac’s tubercle or the carotid tubercle), the ultrasound transducer is slowly moved in a cephalad or caudad direction until the C6 vertebral body is identified. Once the position of the C6 vertebral body is confirmed, it can serve as a landmark to count from should the clinician desire to block the C5 or C7 nerve root. The C7 transverse process can be easily distinguished from the C6 transverse process by the lack of a taller and more pointed anterior tubercle on the C7 transverse process. At the C7 level, the C7 nerve root is located just anterior to the posterior tubercle. At each level, the anterior and posterior tubercle humps will appear as a hyperechoic two-humped camel with the hypoechoic nerve located between the two humps. Color Doppler imaging can help identify the vertebral artery (Fig. 45-14). Once the correct level has been confirmed, a 22-gauge,

B

Anteroposterior (A) and lateral (B) views with contrast injection. (From Raj PP, Lou L, Erdine S, et al: Interventional Pain Management: Image-Guided Procedures, 2nd ed. Philadelphia, Saunders, 2008.)

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SIDE EFFECTS AND COMPLICATIONS Nerve root

Carotid artery

Posterior tubercle

Anterior tubercle

C6 vertebra

Figure 45-13 A transverse ultrasound image of the C6 vertebra is obtained, and the anterior and posterior tubercles of the transverse process are identified. These tubercles have been described as a twohumped camel. The cervical nerve root lies between the two humps.

31 2-inch blunt needle is inserted using an in-plane approach and is advanced until the needle tip is in proximity to the nerve root, which rests between the anterior and posterior tubercle (see Fig. 45-14). After gentle aspiration, 0.25 to 0.5 mL of solution is injected with care being taken to avoid the vertebral artery, which is located anteriorly in relation to the facet joints. The needle is removed and pressure is placed on the injection site to avoid hematoma formation.

Post.

Ant.

N pt

Figure 45-14

at

Short-axis transverse ultrasound image showing the anterior tubercle (at) and the posterior tubercle (pt) of the cervical transverse process as the two-humped camel sign. Arrows are pointing to the needle in place at the posterior aspect of the intervertebral foramen. Ant., Anterior; N, nerve root; Post., posterior. (From Narouze S, Vydyanathan A: Ultrasound-guided cervical transforaminal injection and selective nerve root block. Tech Reg Anesth Pain Manag 13[3]:137141, 2009.)

Basically, all the potential side effects and complications associated with the interlaminar approach to the cervical epidural space can occur with the transforaminal approach, but the transforaminal approach is associated with a statistically significant increased incidence of persistent paresthesias and trauma to neural structures, including the spinal cord. As mentioned earlier, if the needle is placed too far into the neural foramen when the transforaminal approach to the cervical epidural space is used, unintentional injection into the spinal cord may occur with resultant quadriplegia or death. Because of the potential for hematogenous spread via Batson’s plexus, local infection and sepsis represent absolute contraindications to use of the cervical approach to the epidural space. Unlike with the caudal approach to the epidural space, anticoagulant therapy and coagulopathy are absolute contraindications to cervical epidural nerve block because of the risk of epidural hematoma. Unintentional dural puncture during cervical epidural nerve block should occur less than 0.5% of the time with the interlaminar approach and at a slightly higher frequency when the transforaminal approach is used. Failure to recognize unintentional dural puncture can result in immediate total spinal anesthesia with associated loss of consciousness, hypotension, and apnea. It is also possible to unintentionally place a needle intended for the epidural space into the subdural space. If subdural placement is unrecognized and epidural doses of local anesthetics are administered, the signs and symptoms are similar to those of massive subarachnoid injection with prolonged temporal onset, although the resulting motor and sensory block may be spotty. The cervical epidural space and spinal nerve canals are highly vascular. Intravenous placement of the epidural needle occurs in about 0.5% to 1% of patients undergoing cervical epidural anesthesia. The incidence of this complication is increased in patients with distended epidural veins, such as those with foraminal obstruction secondary to herniated nucleus pulposus or tumor as well as those with a large intra-abdominal tumor mass. If the misplacement is unrecognized and local anesthetic is injected directly into an epidural vein, significant local anesthetic toxicity will result. Damage to or injection into the segmental artery can occur with increased incidence when the transforaminal approach to the epidural space is used but is more common at the C5-C7 neural foramina on the right. Needle trauma to the epidural veins may result in selflimited bleeding, which may cause postprocedure pain. Uncontrolled bleeding into the epidural space may result in compression of the spinal cord with the rapid development of neurologic deficit. Although significant neurologic deficit secondary to epidural hematoma after cervical epidural block is exceedingly rare, this devastating complication should be considered whenever there is rapidly developing neurologic deficit after cervical epidural nerve block. Neurologic complications after cervical nerve block are uncommon if proper technique is used and excessive

sedation is avoided. Direct trauma to the spinal cord or nerve roots is usually accompanied by pain. However, the patient may experience little or no pain with needle insertion into the cord, and multiple fluoroscopic views are required to avoid this potentially devastating complication. If significant pain occurs during placement of the epidural needle or during the injection of contrast medium or local anesthetic with or without steroid, the physician should immediately stop and ascertain the cause of the pain to avoid the possibility of additional neural trauma and serious sequelae. Although uncommon, infection in the epidural space remains an ever-present possibility, especially in the immunocompromised patient with acquired immunodeficiency syndrome or cancer. If epidural abscess occurs, emergent surgical drainage to avoid spinal cord compression and irreversible neurologic deficit is usually required. Early detection and treatment of infection are crucial to avoid potentially life-threatening sequelae.

Clinical Pearls Some practitioners recommend the use of a blunt-tipped needle for the transforaminal approach to the cervical epidural space, whereas others believe that a sharper needle is better suited for this technique. Any significant pain or sudden increase in resistance during injection suggests incorrect needle placement, and the practitioner should stop injecting immediately and reassess the position of the needle. Because pain is an important indication of improper needle placement, excessive patient sedation during transforaminal cervical injections should be avoided. The use of fluoroscopy and injection of contrast medium to ensure correct needle placement and lack of vascular uptake will help decrease the incidence of complications associated with this procedure. As mentioned, the use of sedation in patients in the prone position requires special attention to monitoring.

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LYSIS OF CERVICAL EPIDURAL ADHESIONS: RACZ TECHNIQUE

C H A P T E R

193

46

Lysis of Cervical Epidural Adhesions: Racz Technique CPT-2015 Code Lysis of Adhesions—Decompression of Nerve Two Day Lysis of Adhesions—Decompression of Nerve One Day

62263 62264

Relative Value Units Injection Procedure Two Day Injection Procedure One Day

30 25

INDICATIONS Lysis of epidural adhesions has been used to treat a variety of painful conditions (Box 46-1). It is postulated that the common denominator in each of these pain syndromes is the compromise of spinal nerve roots as they traverse and exit the epidural space by adhesions and scarring (Fig. 46-1). It is thought that these adhesions and scar tissue not only restrict the free movement of the nerve roots as they emerge from the spinal cord and travel through the intervertebral foramina but also result in

dysfunction of epidural venous blood and lymph flow. This dysfunction leads to additional nerve root edema, which further compromises the affected nerves. Inflammation also may play a part in the genesis of pain, because these nerves are repeatedly traumatized each time the nerve is stretched against the adhesions and scar tissue. Diagnostic categories thought to be amenable to treatment with lysis of epidural adhesions using the Racz technique include failed cervical spine surgery with Box 46-1 Indications for Lysis of Cervical Epidural Adhesions • • • • • • • • • • • •

Perineural fibrosis Failed cervical spine surgery with associated perineural fibrosis Herniated cervical disk Cervical radiculopathy Spinal stenosis Traumatic vertebral body compression fracture Nontraumatic vertebral body compression fracture Metastatic carcinoma of the cervical spine Metastatic carcinoma of the epidural space Multilevel degenerative arthritis Facet joint pain Epidural scarring following infection

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LYSIS OF CERVICAL EPIDURAL ADHESIONS: RACZ TECHNIQUE

ABSTRACT Lysis of epidural adhesions has been used to treat a variety of painful conditions. It is postulated that the common denominator in each of these pain syndromes is the compromise of spinal nerve roots as they traverse and exit the epidural space by adhesions and scarring. Diagnostic categories thought to be amenable to treatment with lysis of epidural adhesions using the Racz technique include failed cervical spine surgery with associated perineural fibrosis, herniated disk, traumatic and nontraumatic vertebral body compression fracture, metastatic carcinoma of the spine and epidural space, multilevel degenerative arthritis, facet joint pain, epidural scarring following infection, and other pain syndromes of the spine that have their basis in epidural scarring and have failed to respond to more conservative treatments.

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A

B

Figure 46-1 Magnetic resonance images of the cervical spine demonstrating significant epidural scarring that was severely compressing the cord at C2-C3 and C3-C4. (From Meilahn JR: Identifying loss of function caused by cervical spondylotic myelopathy in young adults with nonathetoid spastic cerebral palsy. PM R 4[10]:783-786, 2012.)

CLINICALLY RELEVANT ANATOMY

associated perineural fibrosis, herniated disk, traumatic and nontraumatic vertebral body compression fracture, metastatic carcinoma of the spine and epidural space, multilevel degenerative arthritis, facet joint pain, epidural scarring following infection, and other pain syndromes of the spine that have their basis in epidural scarring and have failed to respond to more conservative treatments. A computed tomographic myelogram revealed significant epidural scarring that was severely compressing the cord on the right side at C2-C3 and C3-C4. Deformity of the cord was seen on the right side with atrophy at C2-C3. The patient was diagnosed with spastic quadriparesis secondary to progressive cervical spondylotic myelopathy from epidural scarring and recurrent stenosis, which was particularly worse from C2 to C4-C5.

The superior boundary of the cervical epidural space is the fusion of the periosteal and spinal layers of dura at the foramen magnum. The epidural space continues inferiorly to the sacrococcygeal membrane. The cervical epidural space is bounded anteriorly by the posterior longitudinal ligament and posteriorly by the vertebral laminae and the ligamentum flavum. The vertebral pedicles and intervertebral foramina form the lateral limits of the epidural space. The cervical epidural space is 3 to 4 mm at the C7-T1 interspace with the cervical spine flexed. The cervical epidural space contains fat, veins, arteries, lymphatics, and connective tissue (Fig. 46-2). The epidural space is subject to scarring following infection, inflammation, and surgery.

Int. jugular v. Common carotid a. Spinal arterial branch Anterior radicular a. Anterior spinal a. Posterior radicular a.

C6

Vertebral a. Cervical nerve root Superior articular process Spinal cord Epidural space Ligamentum flavum Spinous process

Figure 46-2

Anatomy of the cervical epidural space. a., Artery; Int., internal; v., vein.

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LYSIS OF CERVICAL EPIDURAL ADHESIONS: RACZ TECHNIQUE

195

Epidural space

C7 Epidural needle

T1

Figure 46-3

TECHNIQUE Intravenous access is established for administration of intravenous sedatives during the injection of solutions via the catheter. Sedation during injection may be necessary because of pain produced by the distraction of the nerve roots as the solution lyses the perineural adhesions. After venous access is obtained, the patient is placed in the prone position with the cervical spine in a flexed position that is comfortable for the patient to allow access to the epidural space. A wide area of skin is then prepared with antiseptic solution so that all the landmarks can be palpated aseptically. A fenestrated sterile drape is placed to avoid contamination of the palpating fingers. At the C7-T1 interspace, the operator’s middle and index fingers are placed on either side of the spinous processes. The position of the interspace is reconfirmed with palpation using a rocking motion in the superior and inferior planes. The midline of the selected interspace is identified by palpating the spinous processes above and below the interspace using a lateral rocking motion to ensure that the needle entry site is exactly in the midline. One milliliter of local anesthetic is used to infiltrate the skin, subcutaneous tissues, and supraspinous and interspinous ligaments at the midline. The interspace and midline are then confirmed with fluoroscopy. After confirmation of the interspace and midline, a 19-gauge, 31 2-inch styletted needle suitable for catheter placement is inserted through the anesthetized area. A right-handed physician holds the epidural needle firmly at the hub with his or her left thumb and index finger. The left hand is placed firmly against the patient’s neck to ensure against uncontrolled needle movements should the patient unexpectedly move. A syringe containing preservative-free saline is attached with constant pressure applied to the plunger of the syringe with the thumb of the right hand, and then the needle and syringe are

continuously advanced in a slow and deliberate manner with the left hand. As soon as the needle bevel passes through the ligamentum flavum and enters the epidural space, there will be a sudden loss of resistance to injection, and the plunger will effortlessly surge forward. If there is uncertainty about needle position, the syringe is gently removed from the needle, and an air or saline acceptance test is carried out by injecting 0.5 to 1 mL of air or sterile preservative-free saline with a well-lubricated sterile glass syringe to help confirm that the needle is within the epidural space (Figs. 46-3 and 46-4). The force

Figure 46-4

Needle tip in the cervical epidural space.

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required for injection should not exceed that necessary to overcome the resistance of the needle. Any significant pain or sudden increase in resistance during injection suggests incorrect needle placement, and the operator should stop injecting immediately and reassess the position of the needle. Needle position should be confirmed by fluoroscopy in both anteroposterior and lateral views. After negative results on aspiration for blood and cerebrospinal fluid, 3 to 5 mL of a water-soluble contrast medium such as iohexol or metrizamide is slowly injected through the previously placed epidural needle under fluoroscopic guidance (Fig. 46-5). The operator should check closely for any evidence of contrast medium in the epidural venous plexus, which would suggest intravenous placement of the needle or subdural or subarachnoid placement and which appears as a more concentrated centrally located density. As the epidural space fills with contrast medium, a Christmas tree shape will appear as the contrast medium surrounds the perineural structures. Defects in this classic Christmas tree appearance are indicative of epidural perineural adhesions. After proper needle placement is confirmed and careful aspiration yields no blood or cerebrospinal fluid, 3 to 4 mL of 0.25% preservative-free bupivacaine and 40 mg of triamcinolone acetate are slowly injected through the epidural needle while the fluoroscope screen is observed. The local anesthetic will force the contrast medium around the adhesions, which will further identify affected nerve roots. After the area of adhesions is identified on epidurogram, the bevel of the epidural needle is turned toward the ventrolateral aspect of the affected side. This facilitates passage of the catheter toward the affected nerves and

Figure 46-5

Contrast medium within the cervical epidural space.

decreases the chance of catheter breakage or shearing. The use of a wire spiral catheter such as the Racz Tun-L-Kath or Racz Brevi-XL epidural catheter will further decrease the incidence of this complication. The catheter is then passed through the needle into the area of adhesions. Multiple attempts may be required to obtain placement of the catheter into the adhesions (Figs. 46-6 and 46-7). The Racz needle allows the catheter to

Epidural space Catheter C7 Epidural needle

T1

Figure 46-6 After the area of adhesions is identified on the epidurogram, the bevel of the epidural needle is turned toward the ventrolateral aspect of the affected side. This facilitates passage of the catheter toward the affected nerves and decreases the chance of catheter breakage or shearing. The use of a wire spiral catheter such as the Racz Tun-L-Kath or Racz Brevi-XL epidural catheter will further decrease the incidence of this complication.

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LYSIS OF CERVICAL EPIDURAL ADHESIONS: RACZ TECHNIQUE

197

properties of the hypertonic saline further shrink the nerve root and help treat the perineural edema caused by the venous obstruction secondary to the adhesions. The injection of 10% saline into the epidural space is quite painful, and intravenous sedation may be required if the saline spreads beyond the area previously anesthetized by the 0.25% bupivacaine. This pain is transient and is generally gone within 10 minutes. After the final injection of 10% saline, the catheter is carefully secured, and a sterile dressing is placed. Intravenous administration of cephalosporin antibiotics is recommended by Dr. Racz to prevent bacterial colonization of the catheter while it is in place. This procedure of injecting bupivacaine followed by 5% to 10% saline via the previously placed catheter is repeated the following day. Repeat epidurograms are obtained only if there is a question of catheter migration, because the contrast medium can be irritating to the nerve roots and is quite expensive. The catheter is removed after the last injection. The patient is instructed to keep the area clean and dry and to call at the first sign of elevated temperature or infection. Figure 46-7

Racz catheter within the cervical epidural space.

be withdrawn and repositioned and is preferred over the standard epidural needle. After the catheter is placed within the area of adhesions, catheter aspiration is performed for blood or cerebrospinal fluid. If the aspiration results are negative, an additional 3 to 4 mL of contrast medium is slowly injected through the catheter (Fig. 46-8). This additional contrast medium should be seen spreading into the area of the adhesion. If the contrast material is observed to flow in a satisfactory manner, an additional 3 mL of 0.25% bupivacaine and 40 mg of triamcinolone are injected through the catheter to further lyse the remaining adhesions. Some investigators also recommend the addition of 200 U of hyaluronidase to facilitate the spread of the solutions injected. About 3% of the population may experience some degree of allergic reaction to this drug, and this fact may limit its use. Fifteen minutes after the second injection of bupivacaine, after negative findings on aspiration, 5 to 6 mL of 10% saline is injected in small increments or via infusion pump over 20 to 30 minutes. The hyperosmolar

SIDE EFFECTS AND COMPLICATIONS Complications directly related to epidural lysis of adhesions are generally self-limited, although occasionally, even when the procedure is performed by the best of practitioners, severe complications can occur. Self-limited complications include pain at the injection site, transient neck pain, ecchymosis and hematoma formation over the injection site, and unintended subdural or subarachnoid injection of local anesthetic. Severe complications of epidural lysis of adhesions include unintended subdural or subarachnoid injection of hypertonic saline, persistent sensory deficit in the lumbar and sacral dermatomes, paraparesis or paraplegia, persistent bowel or bladder dysfunction, sexual dysfunction, and infection. Although it is uncommon, unrecognized infection in the epidural space can result in paraplegia and death. Clinically, the signs and symptoms of epidural abscess are a high temperature, spine pain, and progressive neurologic deficit. If epidural abscess is suspected, blood and urine samples should be taken for culture, antibiotics started, and emergent magnetic resonance imaging of the spine performed to allow identification and drainage of any abscess before irreversible neurologic deficit occurs.

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A

B

C

D

E

F

Figure 46-8 A, Cervical anteroposterior radiograph after contrast injection showing restricted spread (loculation). B, Labeled image. C, Contrast entering the neural foramen after hyaluronidase and 0.9% saline injection and side-to-side head movement. D, Labeled image. E, Contrast runoff in the C2-C3-C4 area. F, Labeled image. (From Racz GB, Heavner JE: Complications associated with lysis of epidural adhesions and epiduroscopy. In Neal JM, Rathmell JP, editors: Complications in Regional Anesthesia and Pain Medicine. Philadelphia, Saunders, 2007, pp 301-311.)

Clinical Pearls Lysis of epidural adhesions is a straightforward technique that may provide pain relief in a carefully selected subset of patients. This technique should not be viewed as a starting point or stand-alone treatment in the continuum of pain management modalities but should be carefully integrated into a comprehensive pain management treatment plan. The identification of preexisting neurogenic bowel or bladder dysfunction by the

use of urodynamic testing and careful neurologic examination before lysis of epidural adhesions is mandatory so that these preexisting problems are not erroneously attributed to the procedure. Careful screening for preexisting sexual dysfunction is also indicated before lysis of epidural adhesions, for the same reason.

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CERVICAL SELECTIVE NERVE ROOT BLOCK

C H A P T E R

199

47

Cervical Selective Nerve Root Block CPT-2015 Code Local Anesthetic Steroid Additional Level

64479 64479 64480

Relative Value Units Local Anesthetic Steroid Each Additional Level

10 10 10

INDICATIONS Selective nerve root block of the cervical nerve roots is indicated primarily as a diagnostic maneuver to determine whether a specific nerve root is subserving a patient’s pain. Unfortunately, there is much confusion regarding both the clinical indications and technical aspects of performing this technique, which has led to problems in assessing the clinical utility of selective nerve block. For purposes of this chapter, selective nerve root block of the cervical nerve roots is defined as the placement of a needle just outside the neural foramen adjacent to the target nerve root without entering the epidural, subdural, or subarachnoid space. If these conditions are met, selective spinal nerve root block is diagnostic for the specific targeted root. However, if the needle enters the neural foramen and local anesthetic is injected, the potential exists to block not only the targeted nerve root but also the sinovertebral medial branch, the ramus communicans. In this situation, if the local anesthetic does not enter the epidural, subdural, or subarachnoid space, the diagnostic block can be

considered to be specific to that spinal segment and nerve root. However, if the local anesthetic enters the epidural, subdural, or subarachnoid space, the diagnostic block cannot be said to be specific to a given nerve root or segment and may be simply a diagnostic neuraxial block (Fig. 47-1). Although these distinctions may seem minor, the implications of failing to recognize these subtle differences relative to technique can lead to surgical interventions that fail to benefit the patient.

CLINICALLY RELEVANT ANATOMY The superior boundary of the cervical epidural space is the fusion of the periosteal and spinal layers of dura at the foramen magnum. The epidural space continues inferiorly to the sacrococcygeal membrane. The cervical epidural space is bounded anteriorly by the posterior longitudinal ligament and posteriorly by the vertebral laminae and the ligamentum flavum. The vertebral pedicles and intervertebral foramina form the lateral limits of the epidural space. The cervical epidural space is 3 to 4 mm at the C7-T1 interspace with the cervical spine flexed. The cervical epidural space contains a small amount of fat, veins, arteries, lymphatics, and connective tissue. The nerve roots exit their respective neural foramina and move anteriorly and inferiorly away from the cervical spine (Fig. 47-2). The vertebral artery lies ventral to the neural foramen at the level of the uncinate process. Care must be taken to avoid this structure. When selective nerve root block of the cervical nerve roots is performed, the goal is to place the needle just outside the neural foramen of the affected nerve root with precise application of local anesthetic. As mentioned earlier, placement of the needle within the neural foramina may change how the information obtained from this diagnostic maneuver should be interpreted.

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CERVICAL SELECTIVE NERVE ROOT BLOCK

ABSTRACT

KEY WORDS

Selective nerve root block of the cervical nerve roots is indicated primarily as a diagnostic maneuver to determine whether a specific nerve root is subserving a patient’s pain. When selective nerve root block of the cervical nerve roots is performed, the goal is to place the needle just outside the neural foramen of the affected nerve root with precise application of local anesthetic. If the needle enters the neural foramen and local anesthetic is injected, the potential exists to block not only the targeted nerve root but also the sinovertebral medial branch, the ramus communicans. In this situation, if the local anesthetic does not enter the epidural, subdural, or subarachnoid space, the diagnostic block can be considered to be specific to that spinal segment and nerve root. However, if the local anesthetic enters the epidural, subdural, or subarachnoid space, the diagnostic block cannot be said to be specific to a given nerve root or segment and may be simply a diagnostic neuraxial block.

cervical epidural block cervical nerve root cervical spine epidural space

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selective nerve root block sinovertebral nerve subdural space transforaminal nerve block

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Figure 47-3

Oblique view of the cervical neural foramina.

affected neural foramen. When this is accomplished, the beam should be parallel to the targeted nerve root with the nerve in the approximate center of the inferior aspect of the foramen. The skin is then prepared with an antiseptic solution, and a skin wheal of local anesthetic is placed at a point overlying the posterior aspect of the foramen just over the tip of the superior articular process of the level below the affected neural foramen. A 25-gauge, blunt or sharp 2-inch needle is then placed through the previously anesthetized area and advanced until the tip rests against the superior articular process of the level below the targeted neural foramen (Figs. 47-4 and 47-5). This contact provides the operator with an indication of the depth of the neural foramen. Failure to impinge on bone at this point may indicate that the needle has passed through the foramen and rests within the neural canal or the substance of the spinal cord. Failure to identify this problem can lead to disastrous results (see “Side Effects and Complications”).

Figure 47-1

Anteroposterior image taken during a single cervical nerve root block showing improper needle placement. Both the C5 (thick arrow) and C6 (thin arrow) cervical nerve roots are outlined with contrast. The nerve root selected should be the only one visualized. (From Blankenbaker DG, Davis KW, Choi JJ: Selective nerve root blocks. Semin Roentgenol 39[1]:24-36, 2004.)

TECHNIQUE Selective nerve root block of the cervical nerve roots is carried out in a manner analogous to cervical epidural block using the transforaminal approach. The patient is placed in the supine or lateral position. With the patient in the supine or lateral position on the fluoroscopy table, the fluoroscope beam is rotated from a lateral to oblique position to allow visualization of the affected neural foramen at its largest diameter (Fig. 47-3). The fluoroscope beam is then slowly moved from a cephalad to a more caudad position also to allow visualization of the

Int. jugular v. Common carotid a. Spinal arterial branch Anterior radicular a. Anterior spinal a. Posterior radicular a.

C6

Vertebral a. Cervical nerve root Superior articular process Spinal cord Epidural space Ligamentum flavum Spinous process

Figure 47-2

Anatomy of the cervical nerve root and its relationship to the epidural space. a., Artery; Int., internal; v., vein.

47

CERVICAL SELECTIVE NERVE ROOT BLOCK

Figure 47-6

201

Neurogram of a cervical nerve root.

Figure 47-4

A 25-gauge, blunt or sharp 2-inch needle is placed through the area anesthetized previously and advanced until the tip rests against the superior articular process of the level below the targeted neural foramen.

Figure 47-5 Oblique lateral view of the cervical spine during a right C7 nerve root block. The needle tip is positioned toward the posterior inferior aspect of the C6-C7 neural foramen. (From Blankenbaker DG, Davis KW, Choi JJ: Selective nerve root blocks. Semin Roentgenol 39[1]:24-36, 2004.)

After this bony landmark is identified, the needle is withdrawn slightly and redirected caudally and ventrally to impinge on the nerve root just as it exits the neural foramen. The patient should then be warned that a paresthesia will occur and asked to say “There!” as soon as the paresthesia is felt. The needle is then advanced very carefully, because a paresthesia will be elicited as the needle touches the nerve root. Great care must be taken to stay dorsal to the uncinate process, with the target being the center of the foramen. After a paresthesia is elicited in the distribution of the targeted nerve root and the needle bevel is directed laterally, a fluoroscopic image is obtained to confirm that the needle tip is at or near the lateral margin of the lateral mass. A solution containing 0.3 mL of a contrast medium suitable for subarachnoid use is then gently injected under continuous fluoroscopic guidance. The contrast should be seen to flow around the nerve root but should not flow proximally into the epidural, subdural, or subarachnoid space. On a neurogram the affected nerve root should be outlined (Fig. 47-6). Less than 0.5 mL of 4% lidocaine without preservative is then slowly injected under fluoroscopic guidance. The local anesthetic should be seen to flow into the nerve root canal. The injection of contrast and local anesthetic should be stopped immediately if the patient complains of significant pain on injection, although a mild pressure paresthesia is common. After satisfactory injection of the local anesthetic and contrast, the needle is removed, and pressure is placed on the injection site.

SIDE EFFECTS AND COMPLICATIONS Basically, the potential side effects and complications associated with selective nerve root block are the same as

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those associated with cervical epidural block using the transforaminal approach. As mentioned, flow of local anesthetic into the neural foramina reduces the specificity of the diagnostic information obtained with selective nerve root block of the cervical nerve roots. Placement of the needle into the neural foramen may result in inadvertent injection into the spinal cord with resultant quadriplegia or death. Ventral needle placement may result in damage to the vertebral artery with the possibility of local anesthetic toxicity and, rarely, stroke. Because of the potential for hematogenous spread via Batson’s plexus, local infection and sepsis represent absolute contraindications to this technique. Anticoagulant therapy and coagulopathy are absolute contraindications to selective nerve root block of the cervical nerve roots because of the risk of neuraxial hematoma (Fig. 47-7). Inadvertent dural puncture during selective nerve root block of the cervical nerve roots should rarely occur if attention is paid to the technical aspects of this procedure. However, failure to recognize an unintentional dural or subdural injection can result in immediate total spinal anesthesia with associated loss of consciousness, hypotension, and apnea. This can be disastrous with the patient in the prone position. It is also possible to inadvertently place the injection into the subdural or subarachnoid space with the potential for significant motor or sensory block. This anatomic region is relatively vascular. If intravascular needle placement is unrecognized and local anesthetic is injected directly into a vessel, significant local anesthetic toxicity could result. Damage to or injection into the segmental artery can occur with increased incidence when the selective nerve root block involves the C5-C7 nerve roots on the right. Needle trauma to the epidural veins may result in selflimited bleeding, which may cause postprocedure pain. Uncontrolled bleeding into the epidural space may result in compression of the spinal cord with the rapid development of neurologic deficit. Although significant neurologic deficit secondary to epidural hematoma following selective nerve root block is exceedingly rare, this devastating complication should be considered whenever there is rapidly developing neurologic deficit after cervical epidural nerve block. Neurologic complications after selective nerve root block are uncommon if proper technique is used and excessive sedation is avoided. Direct trauma to the spinal cord or nerve roots is usually accompanied by pain. If significant pain occurs during placement of the needle or during the injection of contrast medium and local anesthetic, the physician should immediately stop and ascertain the cause of the pain to avoid the possibility of additional neural trauma. Although uncommon, infection in the epidural space remains an ever-present possibility, especially in the immunocompromised patient with acquired immunodeficiency syndrome or cancer. If epidural abscess occurs, emergent surgical drainage to avoid spinal cord compression and irreversible neurologic deficit is usually required. Early detection and treatment of infection are crucial to avoid potentially life-threatening sequelae.

A

B Figure 47-7 Computed tomographic scan of the cervical spine in axial view (A) and sagittal reconstruction (B) showing a large epidural hematoma (arrows) occupying the left posterolateral spinal canal. (From Stoll A, Sanchez M: Epidural hematoma after epidural block: implications for its use in pain management. Surg Neurol 57[4]:235-240, 2002.) Clinical Pearls Some practitioners recommend the use of a blunt-tipped needle for the transforaminal approach to the cervical epidural space, whereas others believe that a sharper needle is better suited for this technique. Any significant pain or sudden increase in resistance during injection suggests incorrect needle placement, and the practitioner should stop injecting immediately and reassess the position of the needle. Because pain is an important indication of improper needle placement, excessive patient sedation during selective nerve root block of the cervical nerve roots should be avoided. As mentioned, the use of sedation in patients in the prone position requires special attention to monitoring.

C H A P T E R

48

Brachial Plexus Block: Interscalene Approach CPT-2015 Code Unilateral Neurolytic

64415 64640

Relative Value Units Unilateral Neurolytic

10 20

INDICATIONS The interscalene approach to the brachial plexus is the preferred technique for brachial plexus block when anesthesia or relaxation of the shoulder is required (Fig. 48-1). In addition to having applications for surgical anesthesia, interscalene brachial plexus nerve block with local anesthetic can be used as a diagnostic tool when differential neural blockade is performed on an anatomic basis for the evaluation of shoulder and upper extremity pain. If destruction of the brachial plexus is being considered, this technique can be used in a prognostic manner to indicate the degree of motor and sensory impairment that the patient may experience. Interscalene brachial plexus nerve block with local anesthetic may be used for palliation in acute pain emergencies, including acute herpes zoster, brachial plexus neuritis, shoulder and upper extremity trauma, and cancer pain, during the wait for pharmacologic, surgical, and antiblastic methods to take effect. Interscalene

brachial plexus nerve block is also useful as an alternative to stellate ganglion block for treatment of reflex sympathetic dystrophy of the shoulder and upper extremity. Destruction of the brachial plexus is indicated for the palliation of cancer pain, including invasive tumors of the brachial plexus as well as tumors of the soft tissue and bone of the shoulder and upper extremity (Fig. 48-2). Because of the desperate condition of many patients with aggressive tumors that have invaded the brachial plexus, blockade of the brachial plexus using the interscalene approach may be carried out in the presence of coagulopathy or anticoagulant therapy by using a 25-gauge needle, albeit with an increased risk of ecchymosis and hematoma formation.

CLINICALLY RELEVANT ANATOMY The brachial plexus is formed by the fusion of the anterior rami of the C5, C6, C7, C8, and T1 spinal nerves. There also may be a contribution of fibers from the C4 and T2 spinal nerves. The nerves that make up the plexus exit the lateral aspect of the cervical spine and pass downward and laterally in conjunction with the subclavian artery. The nerves and artery run between the anterior scalene and middle scalene muscles, passing inferiorly behind the middle of the clavicle and above the top of the first rib to reach the axilla (Figs. 48-3 through 48-6). The scalene muscles are enclosed in an extension of prevertebral fascia, which helps contain drugs injected into this region. 203

204

SECTION III

SHOULDER AND UPPER EXTREMITY

Interscalene

Figure 48-1

Supraclavicular

Infraclavicular

Axillary

Distribution of anesthesia for various approaches to brachial plexus block.

TECHNIQUE Landmark and Computed Tomography–Guided Techniques

Figure 48-2 Pancoast’s tumor (adenocarcinoma) with infiltration of the brachial plexus. A 65-year-old man complained of severe pain in the shoulder radiating to the elbow, medial side of the forearm, and fourth and fifth fingers in an ulnar nerve distribution. Screening coronal T1-weighted magnetic resonance image shows the brachial plexus from the region of the roots (long arrows) to the region of the trunks and divisions, where there is tumor invasion (short arrow) and loss of fat planes on the left. (From Stark DD, Bradley WG: Magnetic Resonance Imaging, 3rd ed. St Louis, Mosby, 1999, p 1824.)

Landmark Technique The patient is placed in the supine position with the head turned away from the side to be blocked. A total of 20 to 30 mL of local anesthetic is drawn up in a 30-mL sterile syringe. When the treatment is for painful or inflammatory conditions that are mediated via the brachial plexus, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The patient is asked to raise his or her head against the resistance of the pain management specialist’s hand to aid in identification of the posterior border of the sternocleidomastoid muscle (Fig. 48-7). In most patients, a groove between the posterior border of the sternocleidomastoid muscle and the anterior scalene muscle can be palpated. Identification of the interscalene groove can be facilitated by having the patient inhale strongly against a closed glottis. The skin overlying this area is then prepared with antiseptic solution. At the level of the cricothyroid notch (C6) at the interscalene groove, a 25-gauge, 11 2-inch needle is inserted with a slightly caudad and inferior trajectory (Fig. 48-8). If the interscalene groove cannot be identified, the needle is placed just slightly behind the posterior border of the sternocleidomastoid muscle. The needle should be advanced quite slowly because a paresthesia is almost always encountered when the needle tip impinges on the brachial plexus as it traverses the interscalene space at almost a right angle to the needle tip. The patient should be warned that a paresthesia will occur

48

BRACHIAL PLEXUS BLOCK: INTERSCALENE APPROACH

205

Subclavian v. Ant. scalene m.

1st rib

Subclavian a. Cricoid cartilage

Mid. scalene m. Sternocleidomastoid m.

Clavicle

Axillary sheath Brachial plexus

Figure 48-3

Anatomy of the brachial plexus. a., Artery; ant., anterior; Mid., middle; m., muscle; v., vein.

Glenoid labrum

Supraspinatus m. Distal end of clavicle

Trapezius m.

Subscapularis m.

Inferior omohyoid m. and t.

Acromion

Posterior sternocleidomastoid m.

Deltoid m.

Middle scalene m.

Greater tuberosity of humerus

Brachial plexus Subclavian a.

Humeral head

Brachial plexus

Latissimus dorsi t.

Axillary a.

Biceps brachii m., short head

Axillary v.

Coracobrachialis m. Biceps brachii m., long head

Cephalic v.

A Figure 48-4

B

Serratus anterior m.

Ribs

Sectional anatomy of the brachial plexus. a., artery; m., muscle; t., tendon; v., vein. (From El-Khoury GY, Bergman RA, Montgomery WJ: Sectional Anatomy by MRI and CT, 3rd ed. New York, Churchill Livingstone, 2007, p 27.)

206

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SCM

ScM

ScA

BrPlex ScIA

ScIV

Clav

Figure 48-7

The patient is asked to raise his or her head against the resistance of the pain management specialist’s hand to aid in identification of the posterior border of the sternocleidomastoid muscle.

Lung

Figure 48-5

Sagittal magnetic resonance image demonstrating the brachial plexus (BrPlex) near the midclavicular line. The brachial plexus can be seen over the cupola of the lung between the anterior scalene (ScA) and middle scalene (ScM) muscles, just posterior to the subclavian artery (SclA). Note the location of the clavicle (Clav) and subclavian vein (SclV). SCM, Sternocleidomastoid muscle. (From Ajar A, Hoeft M, Alsofrom GF, et al: Review of brachial plexus anatomy as seen on diagnostic imaging: clinical correlation with computed tomography– guided brachial plexus block. Reg Anesth Pain Med 32[1]:79-83, 2007.)

and asked to say “There!” as soon as the paresthesia is felt. Paresthesia is generally encountered at a depth of about 3 4 to 1 inch. After paresthesia is elicited, gentle aspiration is carried out to identify blood or cerebrospinal fluid. If the aspiration results are negative and no persistent paresthesia into the distribution of the brachial plexus remains, 20 to

Car a SCM

Thy

Tra Eso

ScA ScM

Tumor

C7

BrPlex C8 Vert a and v

Figure 48-6

Computed tomographic image at the level of C7. The brachial plexus (BrPlex) lies anterior to the transverse process of C7, just medial to the groove between the anterior scalene (ScA) and middle scalene (ScM) muscles. The vertebral artery and vein (Vert a and v) lie just medial to the brachial plexus. Other adjacent structures include the sternocleidomastoid muscle (SCM), thyroid gland (Thy), trachea (Tra), and esophagus (Eso). Car a, Carotid artery; (From Ajar A, Hoeft M, Alsofrom GF, et al: Review of brachial plexus anatomy as seen on diagnostic imaging: clinical correlation with computed tomography– guided brachial plexus block. Reg Anesth Pain Med 32[1]:79-83, 2007.)

30 mL of solution is slowly injected, with close monitoring of the patient for signs of local anesthetic toxicity or inadvertent subarachnoid injection. If surgical anesthesia is required for forearm or hand procedures, additional local anesthetic may have to be injected in a more caudad position along the brachial plexus to obtain adequate anesthesia of the lower portion of the brachial plexus. Alternatively, specific nerves may be blocked more distally if augmentation of the interscalene brachial plexus block is desired. Computed Tomography–Guided Technique Traditionally brachial plexus block using the interscalene approach has been performed using the landmark technique described earlier. Recently, the use of ultrasound guidance has been embraced by many clinicians as a way to increase the accuracy and safety of needle placement (see “Ultrasound Guidance” later). However, occasionally a patient comes for brachial plexus block who has a large body habitus or alterations in anatomy secondary to previous neck surgery, tumor infiltration, or radiation therapy that make the use of the landmark or ultrasound-guided technique problematic. For such patients, computed tomographic (CT) guidance offers a good alternative. For CT-guided brachial plexus block using the interscalene approach, the patient is placed in the supine position on the CT table with the head turned away from the side to be blocked in a position analogous to that used for the landmark or ultrasound-guided technique. A scout view is obtained and the C6 vertebral body is identified. Sequential scans are then taken in 3-mm intervals from the bottom of the C5 vertebral body to the middle of the C7 vertebral body. The scans are reviewed and the anterior and middle scalene muscles and the brachial plexus are identified. The relative position of the brachial plexus to the interscalene groove as well as the location of the vertebral and carotid arteries is noted. Special attention is paid to changes in the normal anatomy due to tumor, tissue fibrosis, postsurgical changes, and so on. Once a safe needle path to the brachial plexus has been identified, a styletted 22-gauge, 31 2-inch blunt needle is

48

BRACHIAL PLEXUS BLOCK: INTERSCALENE APPROACH Cricoid cartilage

Sternocleidomastoid m.

Figure 48-8 At the level of the cricothyroid notch (C6) at the interscalene groove, a 25-gauge, 1 1 2-inch needle is inserted with a slightly caudad and inferior trajectory toward the brachial plexus. a., Artery; Ant., anterior; Mid., middle; m., muscle; v., vein.

Subclavian a.

Clavicle

carefully advanced under CT guidance until the needle tip is in proximity to the brachial plexus (Fig. 48-9). After gentle aspiration, the chosen solution is carefully injected while the patient is monitored closely for side effects related to the local anesthetic and/or iodinated contrast medium (Fig. 48-10).

Ultrasound-Guided Technique The patient is placed in the supine position with the head turned away from the side to be blocked. A total of

Ant. scalene m.

207

1st rib

Subclavian v.

Mid. scalene m. Axillary sheath Brachial plexus

15 mL of local anesthetic is drawn up in a 30-mL sterile syringe. When the treatment is for painful or inflammatory conditions that are mediated via the brachial plexus, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The patient is then asked to raise his or her head against the resistance of the pain management specialist’s

Tra SCM Tra SCM

ScA C6

C6

ScM

Tumor

Figure 48-9

Computed tomographic scan at the level of C6 showing a 22-gauge needle in position between the anterior scalene (ScA) and middle scalene (ScM) muscles. Other adjacent structures include the sternocleidomastoid muscle (SCM) and the trachea (Tra). (From Ajar A, Hoeft M, Alsofrom GF, et al: Review of brachial plexus anatomy as seen on diagnostic imaging: clinical correlation with computed tomography– guided brachial plexus block. Reg Anesth Pain Med 32[1]:79-83, 2007.)

Figure 48-10 Computed tomographic scan at the level of C6 demonstrating a 22-gauge needle in position between the anterior and middle scalene muscles after injection (arrow) of 5 mL of neurolytic solution (12% phenol in iohexol 180 mg/mL). Other adjacent structures include the sternocleidomastoid muscle (SCM) and the trachea (Tra). (From Ajar A, Hoeft M, Alsofrom GF, et al: Review of brachial plexus anatomy as seen on diagnostic imaging: clinical correlation with computed tomography–guided brachial plexus block. Reg Anesth Pain Med 32[1]:79-83, 2007.)

208

SECTION III

SHOULDER AND UPPER EXTREMITY Sternocleidomastoid muscle

Interscalene groove with brachial plexus

Figure 48-11

Proper placement of the ultrasound probe transversely on the neck (probe marker pointing to the patient’s right) and corresponding ultrasound findings: interscalene groove with brachial plexus, anterior scalene muscle, middle scalene muscle, and needle placement. (From Tirado A, Nagdev A, Henningsen C, et al: Ultrasound-guided procedures in the emergency department—needle guidance and localization. Emerg Med Clin North Am 31[1]:87-115, 2013.)

Internal jugular vein Carotid artery Anterior scalene muscle

hand to aid in identification of the posterior border of the sternocleidomastoid muscle (see Fig. 48-7). In most patients, a groove between the posterior border of the sternocleidomastoid muscle and the anterior scalene muscle can be palpated. Identification of the interscalene groove can be facilitated by having the patient inhale strongly against a closed glottis. The skin overlying this area is then prepared with antiseptic solution. A linear ultrasound transducer is then placed over the previously identified location in the transverse plane and a sonogram is obtained (Fig. 48-11). The sternocleidomastoid muscles can be identified as a triangular structure lying superficial to the anterior and middle scalene muscles beneath it (Fig. 48-12). The roots of the brachial plexus will be seen to lie between the anterior and middle scalene muscles and will appear as hypoechoic round or slightly oval multifascicular structures with a hyperechoic perineurium (Fig. 48-13). Color Doppler imaging is used to identify the relative positions of the internal jugular vein and the carotid and vertebral arteries (Fig. 48-14). The clinician then moves the ultrasound transducer in a slightly cephalad or caudad direction until the nerves of the brachial plexus can be seen to

Middle scalene muscle

st C5

as

C7

II

ms lateral st: sternocleidomastoid m. as: Anterior scalene m. ms: middle scalene m.

Figure 48-13 Transverse ultrasound image of the interscalene groove obtained with a high-frequency linear transducer. The roots of the brachial plexus can be seen to lie between the anterior and middle scalene muscles and appear as hypoechoic round or slightly oval multifascicular structures with a hyperechoic perineurium. (From Stefanovich P: Ultrasound-guided nerve blocks. In Lennard TA, Walkowski SA, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011, pp 243-253.)

Sternocleidomastoid muscle Sternocleidomastoid

Anterior scalene

II

C6

Anterior scalene muscle

Brachial plexus

Middle scalene muscle

Interscalene grove

Middle scalene

Carotid artery

Figure 48-12 Transverse ultrasound image demonstrating the relationship between the sternocleidomastoid muscle, anterior and middle scalene muscles, interscalene groove, and brachial plexus.

Figure 48-14

Color Doppler imaging is useful in helping to identify the carotid artery and other major vasculature and their relationship to the interscalene grove and brachial plexus.

48

BRACHIAL PLEXUS BLOCK: INTERSCALENE APPROACH

209

Figure 48-16 Proper needle trajectory for ultrasound-guided brachial plexus block using the interscalene approach. Figure 48-15

For best visualization of the brachial plexus when the interscalene approach is used, the ultrasound transducer is moved in a slightly cephalad or caudad direction until the nerves of the brachial plexus can be seen to “align” within the sheath of prevertebral fascia, which gives the nerves the appearance of a stoplight.

“align” within the sheath of prevertebral fascia, which gives the nerves the appearance of a stoplight (Fig. 48-15). When the nerves of the brachial plexus are seen to be aligned within the fascial sheath, a 22-gauge, 31 2-inch styletted needle is advanced under real-time ultrasound guidance using an in-plane approach until the needle tip is in proximity to the nerve (Fig. 48-16). After careful aspiration for blood or cerebrospinal fluid, 15 mL of solution should be slowly injected (Fig. 48-17). The needle is removed and pressure is placed on the injection site to avoid bleeding complications.

Sternocleidomastoid muscle

SIDE EFFECTS AND COMPLICATIONS The proximity to the subclavian artery and other large vessels suggests the potential for inadvertent intravascular injection or local anesthetic toxicity from intravascular absorption. Needle-induced trauma to these vessels can also occur. Given the large doses of local anesthetic required for interscalene brachial plexus block, the pain management specialist should carefully calculate the total milligram dose of local anesthetic that may be given safely. The vascularity of this anatomic region also gives rise to an increased incidence of postblock ecchymosis and hematoma formation. Despite this vascularity, this technique can be performed safely in patients receiving anticoagulant therapy by using a 25- or 27-gauge needle, albeit at increased risk of hematoma, if the clinical situation indicates a favorable risk-to-benefit ratio. These complications can be decreased if manual pressure is applied to the

Interscalene groove with brachial plexus

Internal jugular vein

Needle

Anechoic anesthetic

Carotid artery

Anterior scalene muscle

Figure 48-17

Middle scalene muscle

Real-time ultrasound visualization of hypoechoic anesthetic injectate in interscalene approach to brachial plexus block. (From Tirado A, Nagdev A, Henningsen C, et al: Ultrasound-guided procedures in the emergency department—needle guidance and localization. Emerg Med Clin North Am 31[1]:87-115, 2013.)

210

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SHOULDER AND UPPER EXTREMITY

A

area of the block immediately after injection. Application of cold packs for 20-minute periods after the block also will decrease the amount of postprocedure pain and bleeding the patient may experience. Not only is there the potential for complications involving the vasculature, but the proximity of the brachial plexus to the central neuraxial structures and the phrenic nerve can result in side effects and complications. If the needle is placed too deep, inadvertent epidural, subdural, or subarachnoid injection is a possibility. If the volume of local anesthetic used for this block is accidentally placed in any of these spaces, significant motor and sensory block will result. Unrecognized, these complications can be fatal. It should be assumed that the phrenic nerve also will be blocked when brachial plexus block is performed using the interscalene approach. In the absence of significant pulmonary disease, unilateral phrenic nerve block should rarely create respiratory embarrassment (Fig. 48-18). However, blockade of the recurrent laryngeal nerve with the attendant vocal cord paralysis, combined with paralysis of the diaphragm, may make the clearing of pulmonary and upper airway secretions difficult. Although less likely than with the supraclavicular approach to brachial plexus block, pneumothorax is a possibility.

Clinical Pearls

B Figure 48-18

Chest radiograph before (A) and just after (B) interscalene brachial plexus block. Before surgery, radiograph showed an elevation of the left diaphragm owing to preoperative thoracic trauma. Following intraoperative right-sided interscalene brachial plexus block there was a bilateral elevation of the diaphragm showing bilateral diaphragm dysfunction, presumably due to phrenic nerve paralysis on the right. (From Saint Raymond C, Borel JC, Wuyam B, et al: Persistent phrenic palsy following interscalene block, leading to chronic respiratory insufficiency and requiring long-term non-invasive ventilation. Respir Med CME 1[3]:253-255, 2008.)

The key to safe and successful interscalene brachial plexus block is a clear understanding of the anatomy and careful identification of the anatomic landmarks necessary to perform the block. Poking around for a paresthesia without first identifying the interscalene groove is a recipe for disaster. The pain management specialist should remember that the brachial plexus is quite superficial at the level at which this block is performed. The needle should rarely be inserted deeper than 1 inch in any but the most obese patients. Supplementation of interscalene brachial plexus block by more peripheral block of the ulnar nerve may be required because the C8 fibers are not always adequately anesthetized when the interscalene approach to brachial plexus block is used. Before the brachial plexus block procedure is begun, all patients should undergo careful neurologic examination to identify any preexisting neurologic deficits so that such deficits are not later attributed erroneously to the nerve block.

C H A P T E R

49

Brachial Plexus Block: Supraclavicular Approach CPT-2015 Code Unilateral Neurolytic

64415 64640

Relative Value Units Unilateral Neurolytic

10 20

INDICATIONS The supraclavicular approach to brachial plexus block is an excellent choice when dense surgical anesthesia of the distal upper extremity is required (Fig. 49-1). This technique is less suitable for shoulder problems because it almost always requires supplementation with cervical plexus block to provide adequate cutaneous anesthesia of the shoulder.

Interscalene

Figure 49-1

Supraclavicular

In addition to having applications for surgical anesthesia, supraclavicular brachial plexus nerve block with local anesthetic can be used as a diagnostic tool when differential neural blockade is performed on an anatomic basis in the evaluation of upper extremity pain. If destruction of the brachial plexus is being considered, this technique can be used in a prognostic manner to indicate the degree of motor and sensory impairment that the patient may experience. Supraclavicular brachial plexus nerve block with local anesthetic may be used for palliation in acute pain emergencies, including acute herpes zoster, brachial plexus neuritis, upper extremity trauma, and cancer pain, during the wait for pharmacologic, surgical, and antiblastic methods to take effect (Fig. 49-2). Supraclavicular brachial plexus nerve block is also useful as an alternative to stellate ganglion block for treatment of reflex sympathetic dystrophy of the upper extremity. Destruction of the brachial plexus via the supraclavicular approach is indicated for the palliation of cancer pain, including pain secondary to invasive tumors of the brachial plexus as well as tumors of the soft tissue and

Infraclavicular

Axillary

Distribution of anesthesia for various approaches to brachial plexus block.

211

212

SECTION III

SHOULDER AND UPPER EXTREMITY

Figure 49-2 Massive upper extremity trauma is amenable to both surgical anesthesia and pain control with brachial plexus block using the supraclavicular approach. (From Herter F, Ninkovic M, Ninkovic M: Rational flap selection and timing for coverage of complex upper extremity trauma. J Plast Reconstr Aesthet Surg 60[7]:760-768, 2007.)

clavicle, after preparation of the skin with antiseptic solution, a 11 2-inch needle is inserted directly perpendicular to the table top (Fig. 49-6). This perpendicular trajectory is known as the plumb bob approach in reference to a mason’s plumb bob (Fig. 49-7). The needle should be advanced quite slowly, because a paresthesia is almost always encountered at a depth of about 3 4 to 1 inch (Fig. 49-8). The patient should be warned that a paresthesia will occur and asked to say “There!” as soon as the paresthesia is felt. If a paresthesia is not elicited after the needle has been slowly advanced to a depth of 1 inch, the needle should be withdrawn and readvanced with a slightly more cephalad trajectory. This maneuver should be repeated until a paresthesia is elicited. If the first rib is encountered before a paresthesia is obtained, the needle should be walked laterally along the first rib until a paresthesia is elicited (Fig. 49-9). The needle should never be directed in a more medial trajectory or pneumothorax is likely to occur.

bone of the upper extremity. Because of the potential for intrathoracic hemorrhage, the interscalene approach to brachial plexus block should be used in patients who are receiving anticoagulant therapy only if the clinical situation indicates a favorable risk-to-benefit ratio.

CLINICALLY RELEVANT ANATOMY The brachial plexus is formed by the fusion of the anterior rami of the C5, C6, C7, C8, and T1 spinal nerves. There is also a contribution of fibers from the C4 and T2 spinal nerves in many patients. The nerves that make up the plexus exit the lateral aspect of the cervical spine and pass downward and laterally in conjunction with the subclavian artery (Fig. 49-3). The nerves and artery run between the anterior scalene and middle scalene muscles, passing inferiorly behind the middle of the clavicle and above the top of the first rib to reach the axilla (Fig. 49-4). The scalene muscles are enclosed in an extension of prevertebral fascia, which helps contain drugs injected into this region.

Vertebral a.

C3

Phrenic n.

C4

Middle scalene m.

C5

Accessory phrenic n.

C6 C7

Anterior scalene m.

T1

TECHNIQUE Landmark Technique The patient is placed in the supine position with the head turned away from the side to be blocked. A total of 10 mL of local anesthetic is drawn up in a 20-mL sterile syringe. When the treatment is for painful conditions that are mediated via the brachial plexus, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The patient is asked to raise his or her head against the resistance of the pain management specialist’s hand to aid in identification of the posterior border of the sternocleidomastoid muscle. The point at which the lateral border of the sternocleidomastoid attaches to the clavicle is then identified (Fig. 49-5). At this point, just above the

Clavicle First rib Sternocleidomastoid m.

Figure 49-3

The supraclavicular approach takes advantage of the compactness of the brachial plexus as it courses under the clavicle and over the first rib. Note that the plexus resides posterior and lateral to the subclavian artery. a., Artery; m., muscle; n., nerve. (From Neal JM: Upper extremity blocks. In Benzon HT, Rathmell JP, Wu CL, et al, editors: Raj’s Practical Management of Pain, 4th ed. Philadelphia, Mosby, 2008, pp 871-887.)

Coracoid Omohyoid m., process Cords of brachial Axillary a. inferior belly Trapezoid lig., plexus coracoclavicular portion Distal clavicle

Anterior scalene m.

Acromioclavicular joint Acromion

Middle scalene m.

Supraspinatus t. Humeral head Subscapularis m.

External jugular v. Subclavian a. and v. Thyrocervical trunk

Greater tuberosity of humerus

Trachea Right brachiocephalic v.

Deltoid m.

Superior vena cava

Biceps brachii t., long head Cephalic v.

Right lung

Biceps brachii m.

A Figure 49-4

B

Biceps brachii m., short head

Serratus Ribs Axillary v. anterior m.

Coracobrachialis m.

Sectional anatomy of the supraclavicular region. a., artery; lig., ligament; m., muscle; t., tendon; v., vein. (From El-Khoury GY, Bergman RA, Montgomery WJ: Sectional Anatomy by MRI and CT, 3rd ed. New York, Churchill Livingstone, 2007, p 27.)

Figure 49-5 The patient is asked to raise his or her head against the resistance of the pain management specialist’s hand to aid in identification of the posterior border of the sternocleidomastoid muscle. The point at which the lateral border of the sternocleidomastoid attaches to the clavicle is then identified. This is the point of needle insertion when brachial plexus block is performed using the supraclavicular approach.

Sternocleidomastoid m. First rib Subclavian v. External jugular v.

Figure 49-6

The plumb bob supraclavicular approach. The needle is placed above the clavicle, next to the lateral border of the sternocleidomastoid muscle, and directed toward the floor (as a brick mason’s plumb bob would be directed). The needle is incrementally fanned 20 degrees cephalad, then 20 degrees caudad until a paresthesia or motor response is elicited. a., Artery; m., muscle; v., vein. (From Neal JM: Upper extremity blocks. In Benzon HT, Rathmell JP, Wu CL, et al, editors: Raj’s Practical Management of Pain, 4th ed. Philadelphia, Mosby, 2008, pp 871-887.)

Subclavian a. Brachial plexus Needle entry site Clavicle

Middle scalene m. Anterior scalene m.

214

SECTION III

SHOULDER AND UPPER EXTREMITY Sternocleidomastoid m. Clavicle

Figure 49-7

Subclavian v. 1st rib Sternum

Mason using a plumb bob.

After paresthesia is elicited, gentle aspiration is carried out to identify blood or cerebrospinal fluid. If the aspiration results are negative and no persistent paresthesia into the distribution of the brachial plexus remains, 10 mL of solution is slowly injected, with close monitoring of the patient for signs of local anesthetic toxicity or inadvertent neuraxial injection.

Ultrasound-Guided Technique The patient is placed in the supine position with the head turned away from the side to be blocked. A total of 10 mL of local anesthetic is drawn up in a 20-mL sterile syringe. When the treatment is for painful conditions that are mediated via the brachial plexus, a total of 80 mg of depot-steroid is added to the local anesthetic with the first

Mid. scalene m.

Subclavian a.

Brachial plexus

Ant. scalene m.

Lung

Figure 49-9

A paresthesia will be elicited when the needle impinges on the brachial plexus. a., Artery; Ant., anterior; Mid., middle; m., muscle; v., vein.

block, and 40 mg of depot-steroid is added with subsequent blocks. The patient is asked to raise his or her head against the resistance of the pain management specialist’s hand to aid in identification of the posterior border of the sternocleidomastoid muscle. The point at which the lateral

Sternocleidomastoid m. 1st rib

Figure 49-8

Subclavian v. Mid. scalene m.

Clavicle Brachial plexus

Ant. scalene m. Subclavian a.

The needle should be advanced quite slowly, because a paresthesia is almost always encountered at a depth of about 3 4 to 1 inch. The patient should be warned that a paresthesia will occur and asked to say “There!” as soon as the paresthesia is felt. If a paresthesia is not elicited after the needle has been slowly advanced to a depth of 1 inch, the needle should be withdrawn and readvanced with a slightly more cephalad trajectory. This maneuver should be repeated until a paresthesia is elicited. If the first rib is encountered before a paresthesia is obtained, the needle should be walked laterally along the first rib until a paresthesia is elicited. The needle should never be directed in a more medial trajectory, or pneumothorax is likely to occur. a., Artery; m., muscle; v., vein.

49

215

BRACHIAL PLEXUS BLOCK: SUPRACLAVICULAR APPROACH

Brachial plexus Subclavian artery

1st

rib

Figure 49-10

Proper transverse placement of the high-frequency linear ultrasound transducer over the lateral head of the sternocleidomastoid muscle.

border of the sternocleidomastoid attaches to the clavicle is then identified (see Fig. 49-5). At this point a highfrequency linear ultrasound transducer is then placed in the transverse plane and a sonogram is obtained (Figs. 49-10 and 49-11). The subclavian artery, the brachial plexus, the lung, and the first rib are identified. Color Doppler imaging can be used to further delineate the subclavian artery and other vascular structures (Fig. 49-12). The angle or corner formed by the subclavian artery medially, the first rib inferiorly, and the brachial plexus superolaterally is then identified as the target for needle tip placement, because injection into this location not only blocks the brachial plexus but also blocks fibers that form the ulnar nerve, which can often be missed when a classic landmark approach is used. This ultrasound landmark has been called the corner pocket, with the fibers of the ulnar nerve termed the eight ball due to the contribution of fibers from C8 (Fig. 49-13). When the corner pocket is identified and the clinician reconfirms the relative location of the subclavian artery,

Pleura

Figure 49-12 Color Doppler imaging can be used to further delineate the subclavian artery and other vascular structures.

lung, and first rib, a 22-gauge, 31 2-inch styletted needle is advanced under real-time ultrasound guidance using an in-plane approach until the needle tip is resting within the corner pocket between the subclavian artery and the superior border of the first rib, which places it in proximity to the brachial plexus (Figs. 49-14 and 49-15). After careful aspiration for blood or cerebrospinal fluid, 15 mL of solution is slowly injected in incremental doses. The needle is removed and pressure is placed on the injection site to avoid bleeding complications.

Subclavian artery

Brachial plexus

Subclavian artery First rib Brachial plexus First rib

Pleura

Figure 49-11 Sonogram demonstrating the subclavian artery, brachial plexus, pleura, and first rib.

Pleura

Figure 49-13

The angle or corner formed by the subclavian artery medially, the first rib inferiorly, and the brachial plexus superolaterally is identified as the target for needle tip placement because injection at this location not only blocks the brachial plexus but also blocks fibers that form the ulnar nerve, which can often be missed when a classic landmark approach is used. This ultrasound landmark has been called the corner pocket, with the fibers of the ulnar nerve termed the eight ball due to the contribution of fibers from C8.

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II First rib

sa

II

* Pleura

sa: subclavian artery

Figure 49-15 Figure 49-14 Proper ultrasound transducer position and needle trajectory for brachial plexus block using the supraclavicular approach. (From Stefanovich P: Ultrasound-guided nerve blocks. In Lennard TA, Walkowski SA, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011, pp 243-253.)

SIDE EFFECTS AND COMPLICATIONS The proximity to the subclavian artery and other large vessels suggests the potential for inadvertent intravascular injection or local anesthetic toxicity from intravascular absorption. Given the large doses of local anesthetic required for supraclavicular brachial plexus block, the pain management specialist should carefully calculate the total milligram dose of local anesthetic that may be given

Figure 49-16

Ultrasound scan of the supraclavicular area using a high-frequency linear transducer. Notice the proximity of the pleura to the needle injection site in the corner pocket (asterisk). sa, Subclavian artery. (From Stefanovich P: Ultrasound-guided nerve blocks. In Lennard TA, Walkowski SA, Singla AK, et al, editors: Pain Procedures in Clinical Practice, 3rd ed. Philadelphia, Saunders, 2011, pp 243-253.)

safely. This vascularity also gives rise to an increased incidence of postblock ecchymosis and hematoma formation. These complications can be decreased if manual pressure is applied to the area of the block immediately after injection. Application of cold packs for 20-minute periods after the block also will decrease the amount of postprocedure pain and bleeding the patient may experience. Not only is there the potential for complications involving the vasculature, but the proximity of the brachial

A

B

C

D

Coronal (A) and axial (B) T2-weighted magnetic resonance images revealing a mass in the left supraclavicular region. Intraoperative photographs show tumor exposure (C) and tumor removal (D). (From Huang JH, Samadani U, Zager EL: Case studies for illustration and discussion: peripheral nerve tumors. Neurosurg Clin North Am 15[2]:241-249, 2004.)

plexus to the central neuraxial structures and the phrenic nerve can result in side effects and complications. Although these complications occur less frequently than with interscalene brachial plexus block, inadvertent epidural, subdural, or subarachnoid injection remains a possibility. If the volume of local anesthetic used for this block is accidentally placed in any of these spaces, significant motor and sensory block will result. Unrecognized, these complications can be fatal. It should be assumed that the phrenic nerve also will be blocked at least 30% of the time when brachial plexus block is performed using the supraclavicular approach. In the absence of significant pulmonary disease, unilateral phrenic nerve block should rarely create respiratory embarrassment. However, blockade of the recurrent laryngeal nerve with the attendant vocal cord paralysis, combined with paralysis of the diaphragm, may make the clearing of pulmonary and upper airway secretions difficult. Because of the proximity of the apex of the lung, pneumothorax is a distinct possibility, and the patient should be advised of this.

Clinical Pearls The key to performing safe and successful supraclavicular brachial plexus block is a clear understanding of the anatomy and careful identification of the anatomic landmarks necessary to perform the block. Poking around for a paresthesia without first identifying the necessary anatomic landmarks is a recipe for disaster. The pain management specialist should remember that the brachial plexus is quite superficial at the level at which this block is performed. The needle should rarely be inserted deeper than 1 inch in any but the most obese patients. If strict adherence to technique is observed and the needle is never advanced medially from the lateral border of the insertion of the sternocleidomastoid muscle on the clavicle, the incidence of pneumothorax should be less than 0.5%. Before the brachial plexus block procedure is begun, all patients should undergo careful neurologic examination to identify any preexisting neurologic deficits so that such deficits are not later attributed to the nerve block. These deficits may be caused by unsuspected masses or tumors compromising the brachial plexus (Fig. 49-16).

50

BRACHIAL PLEXUS BLOCK: INFRACLAVICULAR APPROACH

C H A P T E R

217

50

Brachial Plexus Block: Infraclavicular Approach CPT-2015 Code Unilateral Neurolytic

64415 64640

Relative Value Units Unilateral Neurolytic

10 20

INDICATIONS The infraclavicular approach to brachial plexus block is an excellent choice when dense surgical anesthesia of the distal upper extremity is required (Fig. 50-1). This technique is less suitable for shoulder problems because it almost always requires supplementation with cervical plexus block to provide adequate cutaneous anesthesia of the shoulder; however, the infraclavicular approach to brachial plexus block has the advantage of not requiring positioning of the arm to perform the block. This

approach is also suitable for placing a catheter for continuous infusion of local anesthetics due to the ease of catheter fixation. In addition to having applications for surgical anesthesia, infraclavicular brachial plexus nerve block with local anesthetic can be used as a diagnostic tool when differential neural blockade is performed on an anatomic basis in the evaluation of upper extremity pain. If destruction of the brachial plexus is being considered, this technique can be used in a prognostic manner to indicate the degree of motor and sensory impairment that the patient may experience. Infraclavicular brachial plexus nerve block with local anesthetic may be used for palliation in acute pain emergencies, including acute herpes zoster, brachial plexus neuritis, upper extremity trauma, and cancer pain, during the wait for pharmacologic, surgical, and antiblastic methods to take effect (Fig. E50-1). Infraclavicular brachial plexus nerve block is also useful as an alternative to stellate ganglion block for the treatment of reflex sympathetic dystrophy of the upper extremity. Destruction of the brachial plexus via the infraclavicular approach is indicated for the palliation of cancer pain,

50

BRACHIAL PLEXUS BLOCK: INFRACLAVICULAR APPROACH

217.e1

Figure E50-1 Larger lesions of multiple myeloma cause significant pain, bone destruction, and cortical expansion as present in this radius lesion. (From McCarthy EF: Hematopoietic tumors. In Folpe AL, Inwards CY, editors: Bone and Soft Tissue Pathology. Philadelphia, Saunders, 2010, pp 379-388.)

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Interscalene

Figure 50-1

Supraclavicular

Infraclavicular

Axillary

Distribution of anesthesia for various approaches to brachial plexus block.

including invasive tumors of the brachial plexus as well as tumors of the soft tissue and bone of the upper extremity. Because of the potential for intrathoracic hemorrhage, the interscalene approach to brachial plexus block should be used in patients who are receiving anticoagulant therapy only if the clinical situation indicates a favorable risk-to-benefit ratio.

CLINICALLY RELEVANT ANATOMY The brachial plexus is formed by the fusion of the anterior rami of the C5, C6, C7, C8, and T1 spinal nerves. There is also a contribution of fibers from C4 and T2 spinal nerves in many patients. The nerves that make up the plexus exit the lateral aspect of the cervical spine and pass downward and laterally in conjunction with the subclavian artery (Fig. 50-2). The nerves and artery run between the anterior scalene and middle scalene muscles, passing inferiorly behind the middle of the clavicle and above the top of the first rib to reach the axilla (Fig. 50-3). The scalene muscles are enclosed in an extension of prevertebral fascia, which helps contain drugs injected into this region.

TECHNIQUE Landmark Technique The patient is placed in the supine position with the head turned away from the side to be blocked. A total of 28 mL of local anesthetic is drawn up in a 30-mL sterile syringe. When the treatment is for painful conditions that are mediated via the brachial plexus, a total of 80 mg of depotsteroid is added to the local anesthetic with the first block,

and 40 mg of depot-steroid is added with subsequent blocks. Brachial plexus block using the infraclavicular approach can be carried out by identifying each cord of the brachial plexus by eliciting a paresthesia, or the discomfort and risk to the patient can be avoided by using a nerve stimulator to minimize trauma to the neural structures. The coracoid process is identified, and at a point 2 cm caudad and 2 cm medial, the skin is prepared with antiseptic solution. A 22-gauge, 80-mm stimulating needle is then inserted with a posterior trajectory directly perpendicular to all planes. The needle should be advanced quite slowly, because a paresthesia is almost always encountered. Stimulation of each cord produces a characteristic motor response, with stimulation of the posterior cord causing the little finger to move posteriorly, stimulation of the medial cord causing the little finger to move medially, and stimulation of the lateral cord resulting in lateral movement of the little finger. The posterior cord lies deepest and in the middle of the neurovascular bundle, and it is important to identify and block this cord in addition to the medial and lateral cords to ensure complete anesthesia (Fig. 50-4). After a satisfactory stimulation pattern is elicited, gentle aspiration is carried out to identify blood or cerebrospinal fluid. If the aspiration results are negative and no persistent paresthesia into the distribution of the brachial plexus remains, 28 mL of solution is slowly injected, with close monitoring of the patient for signs of local anesthetic toxicity or inadvertent neuraxial injection.

Ultrasound-Guided Technique The patient is placed in the supine position with the head in neutral position and the ipsilateral arm abducted to

50

Vertebral a.

C3

Phrenic n.

C4

Middle scalene m.

C5

Accessory phrenic n.

C6

BRACHIAL PLEXUS BLOCK: INFRACLAVICULAR APPROACH

219

Axillary artery

Lateral cord

2 cm 2 cm

C7 Anterior scalene m.

T1 Medial cord Posterior cord

Figure 50-4

Anatomy of the infraclavicular space. The infraclavicular approach to brachial plexus block. The entry point is marked after identifying the lateral edge of the coracoid process and then moving 2 cm medial and 2 cm caudad. A needle is then directed posteriorly toward the three cords of the brachial plexus and the axillary artery, which is approximately 4 ± 1.5 cm from the skin. (From Neal JM: Upper extremity blocks. In Benzon HT, Rathmell JP, Wu CL, et al, editors: Raj’s Practical Management of Pain, 4th ed. Philadelphia, Mosby, 2008, pp 871-887.)

Clavicle First rib Sternocleidomastoid m.

Figure 50-2

The anatomy of the brachial plexus. Note that the plexus resides posteriorly and laterally to the subclavian artery. a., Artery; m., muscle; n., nerve. (From Neal JM: Upper extremity blocks. In Benzon HT, Rathmell JP, Wu CL, et al, editors: Raj’s Practical Management of Pain, 4th ed. Philadelphia, Mosby, 2008, pp 871-887.)

Posterior cord D

Lateral cord Medial cord

C A V PM P

Figure 50-3 Relative disposition of the cords and axillary vessels in the infraclavicular fossa. A, Axillary artery; C, coracoid process; D, deltoid muscle; P, pectoralis major; PM, pectoralis minor; V, axillary vein. (From Bloc S, Garnier T, Komly B, et al: Spread of injectate associated with radial or median nerve–type motor response during infraclavicular brachial-plexus block: an ultrasound evaluation. Reg Anesth Pain Med 32[2]:130-135, 2007.)

bring the artery and plexus closer to the skin, which facilitates ultrasound visualization. A total of 18 mL of local anesthetic is drawn up in a 20-mL sterile syringe. When the treatment is for painful conditions that are mediated via the brachial plexus, a total of 80 mg of depot-steroid is added to the local anesthetic with the first block, and 40 mg of depot-steroid is added with subsequent blocks. The acromioclavicular joint on the affected side is identified by palpation, and an imaginary line is drawn between the acromioclavicular joint and the ipsilateral nipple as a guide to transducer placement (Fig. 50-5). After preliminary identification of the surface landmarks is completed, the skin is prepared with antiseptic solution and 16 mL of local anesthetic is drawn up in a 20-mL sterile syringe, with 40 to 80 mg of depot-steroid added if the condition being treated is thought to have an inflammatory component. A high-frequency linear ultrasound transducer is then placed over the previously identified imaginary line between the acromioclavicular joint and the ipsilateral nipple and a survey scan is taken (see Figs. 50-5 and 50-6). Placement of the transducer in this position provides a short-axis view of the axillary artery and cords of the brachial plexus with the artery appearing as a round pulsatile structure surrounded by the medial, lateral, and posterior cords of the brachial plexus (see Fig. 50-6). The axillary artery, the cords of the brachial plexus, the intercostal muscle, and the pleura and lung are then identified

220

SECTION III

SHOULDER AND UPPER EXTREMITY Resolution Freq 9.0MHz Depth 4cm Sector 60% Gain 54% FR high FPS 53 Hz Dyn 78dB Persist 2 Map 5 Chroma 0 Power –2 MI