Mastering Medical Photography of the Head and Neck

Table of contents :
Mastering Medical Photography of the Head and Neck
Media Center Information
Title Page
Copyright
Dedication
Contents
Preface
Acknowledgments
Contributors
1 Introduction to Medical Photography
2 Photographic Equipment
3 Studio Photography Techniques
4 Small Structures and Macrophotography
5 Postprocessing and Digital Asset Management
6 Smartphones and Telemedicine
7 Approach to the Patient
8 Intraoperative Photography
9 Special Considerations for Reconstructive Surgery
10 Face and Neck
11 Oral Cavity and Oropharynx
12 Sinuses and Nasopharynx
13 Imaging of the Upper Airway and Larynx
Appendix: Suggested Photographic Series for Selected Situations

Citation preview

Mastering Medical Photography of the Head and Neck Scott B. McCusker, MD Otolaryngologist Department of Otolaryngology David Grant USAF Medical Center Travis Air Force Base, California Blaise Douros Freelance Photographer/Videographer Dixon, California

51 illustrations

Thieme Stuttgart • New York • Delhi • Rio de Janeiro

Library of Congress Cataloging-in-Publication Data is available from the publisher.

© 2017 by Georg Thieme Verlag KG Thieme Publishers New York 333 Seventh Avenue, New York, NY 10001, USA +1 800 782 3488, [email protected] Thieme Publishers Stuttgart Rüdigerstrasse 14, 70469 Stuttgart, Germany +49 [0]711 8931 421, [email protected] Thieme Publishers Delhi A-12, Second Floor, Sector-2, Noida-201301 Uttar Pradesh, India +91 120 45 566 00, [email protected] Thieme Publishers Rio, Thieme Publicações Ltda. Edifício Rodolpho de Paoli, 25º andar Av. Nilo Peçanha, 50 – Sala 2508 Rio de Janeiro 20020-906 Brasil +55 21 3172 2297 / +55 21 3172 1896 Cover design: Thieme Publishing Group Typesetting by DiTech Process Solutions, India Printed in Germany by CPI Books ISBN 978-1-62623-442-0 Also available as an e-book: eISBN 978-1-62623-443-7

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Important note: Medicine is an ever-changing science undergoing continual development. Research and clinical experience are continually expanding our knowledge, in particular our knowledge of proper treatment and drug therapy. Insofar as this book mentions any dosage or application, readers may rest assured that the authors, editors, and publishers have made every effort to ensure that such references are in accordance with the state of knowledge at the time of production of the book. Nevertheless, this does not involve, imply, or express any guarantee or responsibility on the part of the publishers in respect to any dosage instructions and forms of applications stated in the book. Every user is requested to examine carefully the manufacturers’ leaflets accompanying each drug and to check, if necessary in consultation with a physician or specialist, whether the dosage schedules mentioned therein or the contraindications stated by the manufacturers differ from the statements made in the present book. Such examination is particularly important with drugs that are either rarely used or have been newly released on the market. Every dosage schedule or every form of application used is entirely at the user’s own risk and responsibility. The authors and publishers request every user to report to the publishers any discrepancies or inaccuracies noticed. If errors in this work are found after publication, errata will be posted at www. thieme.com on the product description page. Some of the product names, patents, and registered designs referred to in this book are in fact registered trademarks or proprietary names even though specific reference to this fact is not always made in the text. Therefore, the appearance of a name without designation as proprietary is not to be construed as a representation by the publisher that it is in the public domain.

This book, including all parts thereof, is legally protected by copyright. Any use, exploitation, orcommercialization outside the narrow limits set by copyright legislation without the publisher’s consent is illegal and liable to prosecution. This applies in particular to photostat reproduction, copying, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.

This book is dedicated to our families: Kimberly, Eliza, and Luke McCusker; Lindsey and Alida Douros.

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Contents

1

Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

viii

Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ix

Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

x

Introduction to Medical Photography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1

Scott McCusker, Blaise Douros

2

Photographic Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

17

Blaise Douros

3

Studio Photography Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

29

Blaise Douros

4

Small Structures and Macrophotography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

37

Scott McCusker, Blaise Douros

5

Postprocessing and Digital Asset Management . . . . . . . . . . . . . . . . . . . . . . . . . . . .

47

Phil Goetz, Blaise Douros, Scott McCusker, Michael Benninger

6

Smartphones and Telemedicine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

57

Fawn Hogan

7

Approach to the Patient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

63

Scott McCusker

8

Intraoperative Photography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

71

Scott McCusker, Fawn Hogan

9

Special Considerations for Reconstructive Surgery . . . . . . . . . . . . . . . . . . . . . . . . .

77

Scott McCusker, Fawn Hogan

10 Face and Neck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

85

Scott McCusker

11 Oral Cavity and Oropharynx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

103

Scott McCusker

12 Sinuses and Nasopharynx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

113

Erik Weitzel

13 Imaging of the Upper Airway and Larynx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

123

N. Scott Howard, Scott McCusker

Appendix: Suggested Photographic Series for Selected Situations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Preface Photography is a very important part of modern life, and essentially everyone is a photographer to some degree. Few people make the leap to being serious photographers, and even fewer dedicate themselves to medical photography specifically. My photography journey began when I was in college, using a manual film camera to take primarily nature photos. During residency, I became interested in medical photography as a communication tool, but was frustrated by the lack of formal instructional materials. Once I became an attending physician, I dedicated myself to learning as much about photography as possible, and taught myself how to apply this knowledge to taking better medical photographs. I expanded on and adapted the techniques in the existing literature, borrowing heavily from artistic portraiture techniques, with the primary goal of creating a method that is dependable, repeatable, and allows accurate depiction of the patient’s condition at that particular moment. I refined this method over several years, with steady improvement in image quality, and the final resultant approach is the one presented here. This book’s primary goal is to demystify the process of taking a high-quality medical photograph of the head and neck, so that anyone can create images that are representative and clinically useful. This will require understanding of basic camera functions, camera and studio equipment, and the proper approach to the patient. These fundamentals can then be applied to specific poses and views. Recommendations for image archiving, organization, and processing are also provided. The text of this book is deliberately short, and so detailed explanations of many aspects of photography are omitted. We also deliberately do not endorse any specific brand or model of camera gear, and have provided sample images created with several camera systems for comparison and to illustrate that there are multiple pathways to great images. We instead list the required gear specifications and features that will allow for excellent results. This book also features a very rich collection of online bonus content, including several images and eight instructional videos that demonstrate the photographic method advocated in the text. All of the photographic views referenced in the text are included, as well as a sample RAW file to practice postprocessing techniques. We sincerely hope that this book is helpful to photographers of all levels and that it allows creation of images of the utmost quality. We welcome any feedback for future editions or volumes, and hope that you enjoy reading this book as much as we enjoyed writing it. Scott McCusker

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Acknowledgments Special thanks to our many friends and colleagues who made this book possible, including Elizabeth Schacht, Haley Paskalides, Sara D’Emic, and Tim Hiscock at Thieme; our model Jincy Kelly; KUIU for use of studio photography equipment; Lou Douros and Velocity Ventures for use of studio space; Fay Reyes for stroboscopy assistance; and our many gracious patients who allowed their images to be displayed here.

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Contributors Scott B. McCusker, MD Otolaryngologist Department of Otolaryngology David Grant Medical Center Travis Air Force Base, California Blaise Douros Freelance Photographer/Videographer Dixon, California Philip Goetz President, D-Scope Systems Brooklyn, New York Fawn Hogan, MD Plastic and Reconstructive Surgeon David Grant Medical Center Travis Air Force Base, California Erik Weitzel, MD Chief, Rhinology and Skull Base Surgery San Antonio Military Medical Center San Antonio, Texas N. Scott Howard, MD Chief, Laryngology San Antonio Military Medical Center San Antonio, Texas Michael S. Benninger, MD Chairman, Head and Neck Institute The Cleveland Clinic Cleveland, Ohio

1

1

Introduction to Medical Photography

Scott McCusker, Blaise Douros

Summary This chapter introduces the discipline of medical photography, a specialized genre requiring meticulous control of camera settings and environment to obtain optimum quality images which accurately depict the human body. Fundamental principles of photography including exposure, ISO, aperture, shutter speed, focus, focal length, and composition are discussed. Understanding these is a prerequisite to creating high-quality medical images.

Keywords aperture, composition, depth of field, exposure, focal length, focus, introduction, ISO, medical photography, shutter speed

Introduction Almost everyone in the current era is a photographer to some degree, or at least takes several pictures. Yet very few people, even serious photographers, have any formal training in the specific demands of medical photography. As a result, the quality of medical images is highly variable and often substandard. With proper implementation of the principles and techniques described in this book, the reader will be equipped to create outstanding medical images to accurately document the human face and neck in almost any conceivable clinical situation.

1 – Introduction to Medical Photography

2 Medical photographs are significantly different from snapshots or even artistic portraits (Fig. 1.1). They are taken using standardized views under tightly controlled conditions to accurately display the real state of the patient at that point in time. Unlike artistic photographs, the goal of medical photographs is not beauty, or to show the patient’s best features while hiding their flaws, but to serve as a medical record. For many diseases or clinical situations such as cosmetic surgery, photography has long been recognized as mandatory, but this is far from universal. However, within the head and neck, there is far more need for photography than with other regions of the body, and the ability to create quality images is increasingly important in today’s practice environment. A good photograph can be the difference between a paid and an unpaid insurance claim, a settled and a dismissed malpractice suit, or most importantly, a happy and an unhappy patient. It is beneficial for all physicians who use medical photographs to also learn how to take them. Many physicians are fortunate enough to work with dedicated medical photographers, majority of who are excellent, but even an

Fig. 1.1 Comparison of (a) a snapshot, (b) artistic portrait (continued)

1 – Introduction to Medical Photography

3

Fig. 1.1 (c) medical photograph

outstanding photographer may not know the specific needs of the referring physician or the clinical situation in question. Even a superficial understanding of the photographic principles in this book will allow the physician to communicate with the photographer to achieve optimum results. For medical photographers, this book can be used not only as a reference standard but also as a help to communicate with referring physicians to produce the best quality product. The human face is one of the most commonly photographed subjects, yet it is remarkably difficult to portray it accurately. This book will address each of the difficulties in this process in a stepwise manner, beginning with the basics of photography, then progressing to more advanced topics specific to photography of the head and neck, before ending with an atlas of standardized photographs. With careful study, the right equipment, and a modicum of practice, the reader should have no problem in reliably producing the images found in this volume.

1 – Introduction to Medical Photography

4 1.1

Basic Photographic Principles To create great images, the entire photographic process must be controlled carefully, beginning with acquisition of the image under ideal conditions. Modern cameras allow the user a very large degree of control over several settings which must be optimized. While every camera is different in terms of the exact controls and specifications, there are certain standardized functions which must be understood. The most critical of these are ISO, shutter speed, and lens aperture. The interaction between these three is often referred to as the “exposure triangle.” Other critical basics to understand are depth of field, focal length, focusing modes, the fundamentals of image composition, and standard hand-holding techniques.

1.1.1

Exposure

Exposure is the most critical element of photography. Artistic photographers use exposure techniques to create elements in their images such as blurred backgrounds, sharply frozen action, or blurred motion. Medical photographers must show their subjects in clear, consistent detail, and their exposure choices should reflect that aim. Digital sensors are limited to certain amounts of light at which they will show details; too much light, and the resulting image will show large white regions with no detail at all; too little, and the resulting image will show large black regions similarly lacking detail. A correct exposure renders highlights, shadows, and midtones with proper detail (Fig. 1.2). Exposure can be assessed subjectively by looking at the image and determining if it looks too dark or too bright, or quantitatively by using the histogram feature. A full discussion of histograms is beyond the scope of this book, but in short it allows a graphical display of the tones present in an image. Underexposure creates a left-biased histogram, and overexposure creates a right-biased histogram. Extremes of either type result in “clipping,” where detail is lost in the highlights or shadows. For medical purposes, the ideal histogram is roughly a bell-shaped curve biased slightly to the right of center, with a large midtone peak that correlates with the uniform background. Exposure is controlled by adjusting ISO, shutter speed, and aperture, which also affect the appearance of the image in ways discussed later.

1 – Introduction to Medical Photography

5

Fig. 1.2 Comparison of (a) underexposure, (b) overexposure (continued)

1 – Introduction to Medical Photography

6

Fig. 1.2 (continued) (c) correct exposure

ISO refers to the gain of the sensor or the amount of light required for it to register a specific exposure value. ISO numbers are based on an inverse logarithmic scale, typically beginning at 100, with each doubling of ISO corresponding to a halved amount of required light to generate an exposure. The trade-off for this increased sensitivity is increased noise (grain) and decreased overall image quality (Fig. 1.3). Most modern digital cameras can produce usable images at higher ISOs, but for medical uses in a controlled setting, the lowest ISO, 100, is always used unless otherwise precluded. This usually requires supplemental lighting, discussed further in later chapters.

1 – Introduction to Medical Photography

7

a

b

c Fig. 1.3 Comparison of ISO: (a) 100, (b) 1,600, and (c) 6,400

1 – Introduction to Medical Photography

8 The shutter sits between the lens and the camera’s sensor, and is opened for a specified period of time when the shutter release is depressed. Shutter speed is represented as a fraction of a second during which the shutter is open; thus, 1/60 shows that the shutter is open for 1/60th of a second. Slower shutter speeds result in more light being passed to the sensor, but will result in a blurred image if either the camera or the subject moves while the shutter is open (Fig. 1.4). Fast shutter speeds can freeze motion, but require large amounts of light. If flashes are used, the shutter speed becomes less important and for most medical uses it can be set at 1/125.

1 – Introduction to Medical Photography

9

a

b

c Fig. 1.4 Comparison of shutter: (a) 1/200 second, (b) 1/500 second, and (c) 1/8,000 second

1 – Introduction to Medical Photography

10 Camera lenses feature an adjustable diaphragm (or iris) that controls the amount of light transmitted to the sensor and affects the depth of field (Fig. 1.5). Aperture size is expressed in “f-stops,” the ratio between the largest cross-sectional area of the lens and the aperture. As such, apertures progress inversely: f/1.8 is “large,” or “wide,” and allows more light to reach the sensor, whereas f/22 is “small” or “narrow,” and reduces the amount of light transmitted. Extremes of aperture result in subtle degradation of image quality. For medical uses, an intermediate aperture such as f/11 is usually optimal (Fig. 1.6). Depth-of-field effects are discussed later. The combination of settings mentioned earlier (ISO 100, 1/125, f11) will require significant supplemental lighting to produce an image, which is discussed at length in Chapter 3. At this point, you should be able to put your camera into manual mode and control each of these settings independently, and take some time to experiment with different permutations of the above to understand how they each function and interrelate to create an exposure.

1 – Introduction to Medical Photography

11

Fig. 1.5 Comparison of (a) wide, (b) intermediate, and (c) narrow apertures

Fig. 1.6 Comparison of depth of field at (a) f/2.8, (b) f/11, and (c) f/32

1 – Introduction to Medical Photography

12 1.1.2

Depth of Field and Focal Length

Depth of field refers to the portion of the image that is in sharp focus. The most familiar example comes from portrait photographers, who often use a very narrow depth of field to isolate their subject or a portion of their subject from the background, which is blurred. In medical photography, however, it is desirable to have the subject completely in focus. Depth of field is affected by the focal length and aperture of the camera’s lens. The wider the angle of view of the camera’s lens, the deeper the depth of field; conversely, the narrower the angle of view, the narrower the depth of field. Focal length is referred to in millimeters; the larger the number, the longer the focal length. For example, a 14-mm lens will provide a wide view, while a 300-mm lens is quite narrow, allowing objects at a distance or of a small size to be photographed (Fig. 1.7). A 14-mm lens has an inherently wide depth of field, and as a result, most of the image will be in focus, even at larger apertures. Conversely, a 300-mm lens has a narrower depth of field and will struggle to keep subjects in focus if they are not located near to each other on the focal plane. The f-stop setting of the lens also affects the depth of field. Large apertures like f/2.8 result in a narrow depth of field (only the area at the focus point is sharp)

a Fig. 1.7 Comparison of focal length: (a) 14 mm (continued)

1 – Introduction to Medical Photography

13

b

c Fig. 1.7 (b) 86 mm, (c) 300 mm

1 – Introduction to Medical Photography

14 and allow more light to reach the sensor, while small apertures like f/32 result in a wider depth of field but require much more light for proper exposure. The distance from camera to subject will also affect the depth of field; the closer the subject is, the narrower the depth of field will become. However, at commonly used focusing distances, this is not as great a factor as focal length and f-stop. The narrower the depth of field is, the less of your subject will appear to be in sharp focus. For this reason, you will need to adjust your aperture to account for your lens’ focal length to ensure your subject is in focus. The longer the lens is, the smaller you will need to set your aperture to ensure your depth of field is wide enough to ensure your subject is in focus. Chapter 2 will discuss recommended focal lengths, as well as techniques for using artificial lighting to support the smaller apertures required for wider depth of field.

1.1.3

Focus and Composition

The focusing mechanism in modern cameras can be controlled manually, automatically, or via hybrid methods. For most medical photographs, automatic focusing is ideal as it is fast and highly accurate. Within the autofocus mode are several permutations which are unique to each specific camera body; please consult your manual for details. In most cases, the best submode is a single point, placed over the area of interest for the image. Manual focusing and hybrid techniques are discussed in detail in Chapter 4. Image composition for medical photographs is significantly different than for artistic photographs. For medical photographs, there are specific rules of composition that create standardized views of various anatomic structures. In general, the structure of chief interest is centered in the frame, and surrounding structures are included for context and a sense of scale. A uniform blue background is the most accepted standard, although white, black, or neutral gray can also be used if desired. The choice of blue is largely one of medical culture and tradition as opposed to objective benefit, but it does provide a pleasing contrast with the skin tones, and where lighting is concerned, is much easier to work with than pure white or black backgrounds. The camera must be held steadily to avoid blurring the image and to allow for perfect framing of the image. To do so, it is pressed tightly to the face with the eye on the viewfinder. The right hand holds the handgrip securely, with the

1 – Introduction to Medical Photography

15 index finger on the shutter button. The palm of the left hand is cupped underneath the lens with the thumb around the top of the lens; the thumb and index finger point roughly forward and free to rotate the focus or zoom rings if needed. If a portrait orientation (vertical) is desired, the camera is rotated 90 degrees counterclockwise so that the camera hangs from the handgrip; adjust the left hand so that its orientation is similar to the position previously described. Both elbows remain relatively tight at the sides, not splayed outward. The torso is straight upright but slightly relaxed. If the photographer is standing, the feet are roughly shoulder-width apart and the knees are bent slightly. The left foot may be advanced slightly if desired. To take a picture, gently depress the shutter button halfway and wait until focus is acquired; then, gently press it all the way, taking care not to shake the camera in the process. A useful exercise to practice this is to take the same picture 20 to 30 times in a row and then compare them later to see how much variation occurred from frame to frame. The chapters that follow move rapidly and present much more advanced photographic concepts. Be sure to return to earlier chapters frequently for periodic review or if any confusion arises. Additionally, be sure to review the extensive online content which accompanies the book, including the detailed tutorial videos and sample images. The authors’ personal equipment and software preferences are discussed, but there is a wide range of gear available that can produce superlative results, and personal preferences should be taken as such.

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2

Photographic Equipment

Blaise Douros

Summary This chapter provides detailed descriptions of the photography gear that is required to obtain high-quality medical images. It discusses acceptable options for cameras, lenses, flashes, light meters, and associated accessories, as well as endoscopic imaging systems. The terminology related to this equipment is explained thoroughly, as are the features that are relevant to selecting the best equipment for the specialized demands of medical use.

Keywords DSLR, digital single-lens reflex, endoscope, equipment, flash, lens, light meter, mirrorless, resolution, sensor, speedlight

Introduction Digital photography equipment is practically ubiquitous in the modern era. Nearly everyone carries a camera of some kind, most commonly in the form of a smartphone. While a well-trained photographer can usually maximize inferior equipment to obtain acceptable results, the proper equipment will allow a photographer to reliably create high-quality imagery. The authors of this textbook do not specifically endorse any particular brand of equipment, and note that outstanding results can be obtained with products from any brand: the limiting factor in image quality is usually the photographer’s skill. This chapter discusses the fundamentals of camera equipment, with attention to the features that matter for medical applications.

2 – Photographic Equipment

18 2.1

Camera Bodies and Sensors The camera body contains the imaging component of the digital camera, the sensor. There are two primary factors to consider when evaluating a camera’s sensor: resolution and physical size. Resolution is typically represented in megapixels: higher numbers mean better resolving power. A resolution of 12 megapixels or greater is sufficient for printing in high quality at standard sizes, and many consider a resolution greater than 24 megapixels to be wasted. However, increased resolution allows very large prints to be generated or more aggressive image cropping. The most common standard sensor sizes are full frame, APS-C, and Micro Four Thirds. While larger sensors yield slightly better image quality (especially in terms of reduced noise), excellent images can be produced regardless of the sensor size. The most noticeable effect of sensor size is a change in field of view: larger sensors result in a wider field of view at a given focal length. Full-frame sensors are approximately the same size as 35-mm film, and lens focal lengths are usually referred to in relation to this size. APS-C sensors result in an effective focal length multiplication of 1.5 times, and Micro Four Thirds in doubling. Thus, a 50-mm lens on full frame behaves roughly like a 75-mm lens on APS-C and a 100-mm lens on Micro Four Thirds. In this book, all focal lengths are listed as 35 mm equivalent. There are three main types of camera bodies: point-and-shoot, DSLR, and mirrorless (Fig. 2.1). Smartphones, while superficially most similar to pointand-shoot cameras, will be covered in Chapter 6. To be acceptable for medical use, a camera must feature manual exposure controls, be able to shoot in RAW format, have a configurable focusing system, be compatible with suitable lenses, and be able to synchronize with external flashes. Point-and-shoot (hereafter P&S) cameras are compact and have an integrated camera body and nonremovable lens. While they have the advantages of being cheap, easy to use, and lightweight, most lack the requisite features listed above for medical photography, and as such are not recommended. However, there is a small but growing segment of full-featured, high-end P&S cameras that can be considered although current models are probably not the optimum choice.

2 – Photographic Equipment

19

Fig. 2.1 Assorted camera bodies: full-frame DSLR, APS-C DSLR, mirrorless, P&S

Digital single-lens reflex cameras, or DSLRs, are the usual choice for professional photographers. They feature a large optical viewfinder and interchangeable lenses. The viewfinder works by a mirror-and-prism system to allow real-time preview of the exact image composition. Modern DSLRs also have a Live View function that allows the user to use the rear screen as a viewfinder to display the digital image from the sensor in near real-time. DSLRs are the most technologically mature form of digital camera, and the major brands have a wide selection of lenses available. High-end bodies feature full-frame sensors, while a variety of mid-range to entry-level models feature APS-C sensors. The main differences between entry-level and more advanced cameras relate to ergonomics as opposed to image quality. Professionally oriented bodies will have easy access to critical functions via physical knobs and buttons on the exterior of the body; lower-end models often have fewer controls, and thus require operation of menus to accomplish the same tasks. Almost any modern DSLR, even entry-level models, will be able to provide satisfactory results for a medical photographer, as all of the requisite features listed above are included with every current-generation camera. Battery life is usually quite good, often enough for an entire day of shooting. The only downside of a DSLR is the larger form factor, which is not a major consideration for medical applications.

2 – Photographic Equipment

20 Mirrorless cameras are a newer category beginning to emerge in competition to DLSRs. They are available with the full range of sensor sizes, from full-frame to Micro Four Thirds. Mirrorless cameras are similar in shape and feature set to DSLRs, with the notable omission of the optical viewfinder, relying instead on a Live View function on the rear screen. Some mirrorless cameras also feature an eyepiece with a small internal screen. This results in a smaller form factor but some diminution in battery life and autofocus performance. One advantage of mirrorless cameras is their flexibility in lens choice, as the mirrorless design allows for adapters to be used so that lenses from DSLRs or other brands of camera can be mounted, although this sometimes results in decreased performance or loss of autofocus capability. Mirrorless cameras are rapidly evolving and have not yet reached maturity—in several years, it is possible that they will have surpassed DSLRs.

2.2

Lenses Lenses are the most important component of a photographer’s system, and lens technology has remained largely stable for several years (Fig. 2.2). In general, the lens is the limiting (equipment) factor for image quality, and high-quality lenses are to be used at all times. Lenses are referred to by their actual (not effective) focal length and the minimum f-stop, such as the 85-mm f/1.8. There are two main categories of lenses: prime lenses and zoom lenses. Prime lenses have a fixed focal length, and because they are optically less complex, they are lighter, smaller, usually have a wider maximum aperture, and usually produce higher-quality images than an equivalent focal length on a zoom lens. Zoom lenses cover a range of focal lengths such as 70 to 200 mm. This is made possible by a mechanism that results in a heavier, larger lens with slightly reduced image quality compared with an equivalent prime lens. The diminution of image quality is not usually apparent in controlled studio conditions. When choosing a lens for medical use, the two most important criteria are the focal length and the minimum focusing distance. The use of a zoom or prime lens is entirely up to the photographer’s preference, but it is easier to standardize photographs with a prime lens, as the perspective is fixed. Choose an equivalent

2 – Photographic Equipment

21

Fig. 2.2 Assorted lenses for medical use: 24 to 120 f/4, 105 f/2.8 macro, 85 f/1.8, 16 to 50 f3.5/5.6 mirrorless

focal length between 80 and 200 mm. Longer focal lengths require an unacceptably long distance from photographer to subject and may lack sufficient depth of field, even at small apertures. Shorter focal lengths introduce “perspective distortion,” which results in structures nearer to the camera appearing larger and more protuberant, with the remaining features appearing to recede unnaturally. This is a result of the relative distances of the portions of the subject to the camera as opposed to a lens design flaw. The minimum focusing distance is most relevant for close-up views of individual parts of the face such as the nose, ears, or eyes. With many lenses, it is impossible to get close enough to focus on a specific facial feature. For this reason, it is often preferable to use a macro lens. These lenses are designed to allow very close focusing, even down to a few inches from the subject if needed, which can be very useful for depiction of very small subjects such as the alar cartilages of the nose or a small skin lesion.

2 – Photographic Equipment

22 2.3

Lighting and Metering Obtaining consistent, even, high-quality light is required for high-quality medical photographs (Fig. 2.3). For our purposes, the light must be very bright, come from at least two sources from different directions, and be fully controlled by the user. Continuous light sources such as tungsten bulbs, light-emitting diodes (LEDs), or fluorescent tubes lack sufficient power; thus, multiple off-camera flashes are required, from either battery-powered speedlights or high-powered studio strobes. These are mounted on adjustable stands so that they can be precisely positioned. A speedlight (sometimes rendered “speedlite,” depending on manufacturer) is the most familiar flash unit, and is compact, portable, and usually powered by AA batteries. With the correct sync equipment and settings, speedlights can be used as off-camera flashes with sufficient power and excellent flexibility. Many also feature automatic metering (TTL), which is useful for intraoperative applications. Their disadvantages are the long recharge time between flashes and their short battery life. Monobloc strobes are the workhorse light source for a studio photographer. Compared with speedlights, strobes boast much more power and faster recycle times, but are large and heavy. Strobes can be powered by either a direct wall plug or a large, high-capacity battery pack. Strobes also usually feature modeling lights, a built-in, continuous light source that allows the photographer to preview the lighting in real time prior to taking a picture. Regardless of which type of flash is used, it must be synchronized to fire during the time the shutter is open. This is accomplished in one of three ways: a hard-wired connection, optical triggering, or via radio control. Many flashes incorporate optical and/or radio triggers into their design, and all are compatible with wired sync. Wired sync is the cheapest method, and also highly reliable, but it means the photographer is physically tethered to the lights. Optical triggers rely on line of sight and are less reliable, but also relatively inexpensive. Radio triggers are the most expensive option but highly reliable. A full discussion of sync methods is beyond the scope of this book but any can be used for medical photographs at the preference of the user.

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23

Fig. 2.3 Comparison of speedlight (left) and strobe (right)

The amount of light produced by the flash must be set manually by the user and is expressed in fractions of the unit’s maximum power. This can be done by tedious trial and error, but is best accomplished with an external light meter. After positioning the lights as desired, they are triggered while holding the light meter at the subject’s position. The light meter will then output the required f-stop for proper illumination, and the power can be adjusted until the desired f-stop is reached. For multiple light setups, each light is metered individually; then a final check is performed with all lights together.

2 – Photographic Equipment

24 Take care when metering to use a standardized approach regardless of the patient’s skin tone. This is best accomplished by metering to the blue background and the color checker card. When the histogram is analyzed, lighter-skinned patients will have a more right-biased histogram, whereas darker-skinned patients will produce a left-biased histogram, but the background peak will be of exactly the same brightness. The color of light produced by different light sources is significantly different, though not always readily apparent to the eye. This is addressed by setting the camera’s white balance. If the camera is set to expect the yellow-tinted light inherent in tungsten bulbs, the blue-tinted light of a flash will cause the image to look extremely blue in color, whereas other settings will make it appear too yellow (Fig. 2.4). One tool that can help in postprocessing to correctly calibrate an image is a color checking slate (also depicted in Fig. 2.4). Available in a range of sizes, color checkers are color-accurately-printed with a range of white, gray, black, and colored regions that allow postprocessing software to calibrate an image’s color correctly from a RAW file. Once the lighting is set up, a test shot with a color checker can be extremely helpful in postprocessing to ensure consistent color between images.

Fig. 2.4 Composite image showing effect of (a) overly blue white balance, (continued)

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25

Fig. 2.4 (b) overly yellow white balance, and (c) correct white balance, all of which confirmed with color checker card and digitally superimposed reference color swatches

2 – Photographic Equipment

26 2.4

Endoscopic Equipment Endoscopic photography and videography equipment is significantly different from that of conventional DSLR photography (Fig. 2.5). Most commercially available endoscopic systems are sold as all-in-one systems, consisting of an endoscope, a light source (often integrated into the endoscope itself), a video camera, a recording device, and a playback monitor, but offer the user very limited control over technical parameters of the images captured. The light source used varies between models, and some models offer several switchable sources such as LED, xenon, or halogen. All these produce different color temperatures and so careful white balancing is required when switching light sources. High-definition (HD) output is possible with many systems, although the specific subtype of HD is not standardized, as discussed further in Chapter 5. Still images are generated by “frame grabs” from the video, and are approximately 2 megapixels in size, which is a significantly lower resolution than is possible with DSLR cameras. The term “medical grade” is applied to many display monitors but refers to the ability to clean the exterior with water and does not necessarily imply that it is of high optical quality for serious image review. Most systems are optimized for real-time display of video images as opposed to recording video or printing of still images. For these reasons, to evaluate an endoscopic system, it is important to not just see sample live views, but also to obtain digital stills and video so that all aspects of the system’s quality can be critically appraised. Fiberoptic endoscopes produce inferior images and should be avoided in favor of distal-chip flexible endoscopes or rigid endoscopes. Straight endoscopes of the largest caliber possible offer the highest image quality, but may not produce the best eventual image if they do not fit into the space required or offer the right angulation of view. All endoscopes in current use produce a fish-eye view, that is, an extreme wide-angle field of view with pronounced distortion. This can actually be advantageous in tight spaces as it affords not only a wider field of view, but also improved motion-related depth perception (parallax) and peripheral viewing at increasing angulation (ability to “see around corners”). The distortion created can easily be distracting though, as normal anatomic relationships seen with the naked eye appear quite different under endoscopic conditions, and recalibrating the eye to the normal endoscopic appearance of key structures is critical.

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27

Fig. 2.5 Assorted endoscopes

29

3

Studio Photography Techniques

Blaise Douros

Summary This chapter discusses proper use of studio conditions to create optimum medical images. Light quality, the use of light modifiers, proper arrangement and use of lights, and use of photographic backgrounds are explained in detail with attention to producing repeatable, reliable photographic results.

Keywords background, grid, hair light, light quality, light modifier, soft light, softbox, strobe, umbrella

Introduction Studio photography allows for tight control of every aspect of the environment, light, and camera placement to create reproducible, consistent results. The lighting process is by far the most important factor in studio photography. Through the careful use of multiple flashes and light modifiers, the perfect light is created to accurately and consistently depict the patient’s condition.

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30 3.1

Light Quality and Light Modifiers Photographers describe the appearance of light by various parameters, but most importantly as hard versus soft (Fig. 3.1). Hard light produces sharp, highly defined contrasting shadows. Examples of hard light are direct sunlight or a bare flash bulb. Soft light is characterized by gradual transitions to shadows, and is less directional. Examples of soft light are diffused window light or a flash in a softbox. Two factors influence the hardness of light: the size of the light source and the distance from it to the subject. Larger lights closer to the subject produce softer light. For medical purposes, soft light best depicts skin quality and texture.

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31

Fig. 3.1 Comparison of (a) hard light versus (b) soft light

3 – Studio Photography Techniques

32 The size of light source used in the studio is fixed, and it can only be placed so close to the subject without interfering with their comfort. Thus, the light source must be diffused to have a larger effective area, by use of tools such as softboxes and umbrellas (Fig. 3.2). Softboxes are large, cloth boxes faced with white diffusion fabric, and result in very soft but somewhat directional light. Umbrellas can be either reflective or shoot-through; a reflective umbrella has the flash aimed away from the subject and the umbrella reflects the light back toward the subject. A shoot-through umbrella is made with a similar diffusion fabric as the front face of the softbox, and is placed between a flash aimed at the subject to diffuse the light. Any of these three can be used, but shoot-through umbrellas and softboxes generally allow better soft fill. In many cases, a subtle shadow fill of select areas using a reflector is useful. Only white or silver should be used so as not to induce a color cast. An example of reflector use is on the patient’s lap, to fill in the shadow created under the chin and nose. In some situations, restriction of light to only illuminate select areas of the frame is needed. This is accomplished with light modifiers such as grids, flags, or gobos (short for “go-betweens”). In medical photography, the only common use for this is with “hair lights” discussed later.

3.2

Lighting Design and Setup In medical photography, the aim is to create extremely smooth, even lighting that illuminates as much of the subject as possible, with no areas of deep shadow or overexposure. This can be accomplished by many methods, two of which are described below. Two lights are necessary at minimum, but additional lights can be used for added benefit. The easiest light setup is the use of two strobes with umbrellas or large soft boxes, positioned a few feet above head level and a few feet from the camera to the right and left. The strobes should be metered to provide perfectly balanced illumination to both sides of the face (1:1 lighting ratio). This will produce soft, even illumination of the subject and background, and the shadows cast by the lights will largely fall off-camera. The addition of a reflector positioned on the patient’s lap can be beneficial for fill light. While it is not required, the addition of gridded hair lights positioned behind the patient and directed at the back of the head can help increase the apparent separation of the patient and the background (Fig. 3.3). If this is done, care should be taken to avoid excess spillage or halo that would obscure the contour of the face.

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33

Fig. 3.2 Light modifiers: softbox (left) and grid (right)

Fig. 3.3 Behind-the-scenes view of 4-light setup

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34 An alternate setup that is familiar to many portraitists is “clamshell” lighting, with a softbox on axis above the photographer and another at the patient’s waist level (Fig. 3.4). Hair lights can be added in the same manner as the previous setup. Additional lights are usually required for the background as well. The resulting images are very similar in style to beauty portraits, which is advantageous when dealing with aesthetically sensitive patients such as celebrities or fashion models. Clamshell lighting is a more complicated setup, and is also much more sensitive to patient positioning, requiring adjustments between each individual pose. Because of these factors, this setup is less preferred by the author. Whichever setup is used, it is important that it be done exactly the same way with every patient, every time.

3.3

Photographic Backgrounds Traditionally, a uniform blue background is used, although black, gray, or white could be used (more technically challenging and not recommended). The author’s preference is to use Studio Blue Seamless Background paper, but cloth or paint could be used if desired. The background projects several feet beyond the subject so that its edges are not visible in the frame. The patient should be positioned several feet in front of the background, which avoids shadows on the background and blurs it slightly so that wrinkles or flaws on it are less visible. If the patient is further from the background, not only is space wasted, but it also necessitates a separate lighting setup for the background.

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35

Fig. 3.4 Comparison of (a) 4-light versus (b) clamshell lighting

37

4

Small Structures and Macrophotography

Scott McCusker, Blaise Douros

Summary This chapter discusses the special photographic techniques that are required for depiction of subjects smaller than 1 inch in diameter. Special macrophotography lenses and their characteristics are described, as is the use of a ring flash for appropriate illumination. Manual and hybrid focusing techniques are detailed to address the depth of field limitations inherent to the situation. Image composition for medical macrophotography is described.

Keywords composition, depth of field, focus stacking, focusing, hybrid focus, manual focus, macrophotography, ring flash

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38

Introduction The head and neck are rife with small, important anatomic structures that can be difficult to capture photographically using conventional techniques. For subjects smaller than 2 inch in diameter, the use of macrophotography techniques is required. This requires specialized lenses and flashes, as well as different focusing and composing techniques (Fig. 4.1).

4.1

Lenses for Macrophotography For medical purposes, the best macro lenses have a focal length of 80 to 200 mm. Shorter focal lengths produce an incredibly short working distance that is impractical for medical uses. Macro lens capabilities are also expressed using a maximum reproduction ratio, that is, the ratio between the actual size of the subject and the size of the image on the physical sensor. A 1:1 ratio means that a 35-mm object will occupy an entire full-frame sensor and thus will be magnified approximately 10× life size if printed at 8 × 10 in. It is important to realize

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39

Fig. 4.1 Macrophotography setup

4 – Small Structures and Macrophotography

40 that the actual reproduction ratio changes as the lens is focused. At the minimum focus distance, the object is magnified more, but at larger distances it is less magnified, or not magnified at all. Additionally, close focusing distances result in dramatic diminution of depth of field, even if an incredibly small aperture is used (Fig. 4.2). As an example, the depth of field with a 105-mm lens at 2 m is 6 cm at f/2.8, and 73 cm at f/32, but at the minimum focusing distance (30 cm) and f/2.8 depth of field it is 0.1 cm, and at f/32 only increases to 1.1 cm. For this reason, small apertures are always used for medical macrophotographs, which necessitates use of a large amount of supplemental light.

4.2

Lighting for Macrophotography Lighting for medical macrophotography is best accomplished with a ring flash unit. This attaches to the front of the lens to provide smooth, even illumination of the subject. Conventional flash units would be blocked by the camera and photographer. While the light from a ring flash is often incorrectly described

Fig. 4.2 Macro depth of field comparison at (a) f/3.8, (continued)

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41

Fig. 4.2 (b) f/11, and (c) f/32

4 – Small Structures and Macrophotography

42 as “shadowless,” it in fact casts shadows directly away from the lens, which provides the desired quality of light on skin, but produces unusual-appearing shadows on any visible background material. Unlike studio strobes, ring flashes are typically used in TTL mode (an automated flash control mode that adjusts the flash exposure based on the camera’s built-in light meter), although the metering sensors can often be confused when dealing with dark areas such as the oral cavity. A dim headlight can be used for supplemental illumination in this circumstance.

4.3

Special Focusing Techniques As discussed earlier, focusing a macro lens changes far more than just the distance between the focus point and the lens; it changes the magnification. As such, simple use of the autofocus mechanism is inadequate, and several advanced focusing techniques are required. One method is to switch to a purely manual focus. This can be aided by prefocusing at a desired reproduction ratio or focusing distance, which is generally printed on the focusing ring of the lens. Once the focus is close, simply move the camera a few millimeters closer to or farther from the subject for fine-tuning, without adjusting the focus ring. An alternate approach preferred by the author is a hybrid approach of first prefocusing manually, then using the autofocus in single-point mode for fine-tuning. With either method, take several pictures with slight focus variations between them and select the sharpest for eventual use. Another technique used by many macrophotographers is “focus stacking,” which involves taking multiple pictures at slightly different focus levels, and then digitally combining the sharp sections from each frame, resulting in an increase in the apparent depth of field (Fig. 4.3). At the time of this writing, this technique is cumbersome and has not been widely accepted for medical uses, but as software solutions for image compositing become more advanced, it is likely that focus stacking will become the standard for macrophotography, especially if it is combined with “light field photography,” which is a new method (still in its infancy) of capturing the entire field of focus using specialized cameras.

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43

Fig. 4.3 Comparison of depth of field at (a) f/32 versus (b) focus stacking

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44 4.4

Image Composition There are no standardized macrophotographic view series in the head and neck. Instead, frame the lesion/structure with a small border of normal or adjacent tissue circumferentially (Fig. 4.4). For larger lesions, it can also be useful to take a macro image of a representative portion thereof, so as to best appreciate the subtleties of its texture or other character. Additionally, be sure to obtain the standard photographic series of the relevant portions of the head and neck to show the lesion in context. If possible, orient the lesion parallel to the focal plane given the narrow depth of field. For lesions with subtle texture or contour, oblique lighting is used to demonstrate this better than a standard ring flash, as the additional shadows created will help show the texture. Some ring flashes have a feature allowing half of the ring to be dimmed slightly, or diffusion material can be used to block some of the light from one half of the ring.

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45

Fig. 4.4 Macro view of skin lesion

47

5

Postprocessing and Digital Asset Management

Phil Goetz, Blaise Douros, Scott McCusker, Michael Benninger

Summary This chapter discusses technical considerations for optimizing image quality after the time of capture, as well as methods for organizing an image library, backup methods, and techniques for speeding workflow such as use of presets. Detailed discussion of video formats, compression, and archival solutions follows, with an attention to characteristics that should be respected when choosing an endoscopy and video archival system.

Keywords color management, compression, encoding, endoscopy, file format, postprocessing, preset, video, workflow

5.1

Postprocessing and Digital Asset Management for Photography There are several steps that occur between the time of image capture and display of a finished image, and it is important to take control of this whole process for the best results. It is also important to develop robust systems to sort, store, and protect the entire library of images. Optimizing the postprocessing workflow not only saves time, but also improves results.

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48 Prior to taking any pictures, there are a few important preparatory steps. Use only high-quality, high-capacity memory cards, which are not only faster and more reliable, but also carry more robust warranties. If your camera has multiple card slots, set it to record a copy of the image to each card (instant backup). Format the memory card with the camera immediately after the images from the previous shoot have been stored safely. Set the camera to RAW mode, lossless compressed, if available, to allow the most flexibility for controlling light and color later. Ensure the date and time are properly set on the camera, as this information will be stored with the rest of the image metadata. Finally, ensure that you have extra fully charged batteries, and consider obtaining a second camera in case of a malfunction. During the shoot, there are a few tips and tricks to facilitate later image processing. First, make a patient placard with their name and pertinent information. The first image from the shoot is of the patient holding the placard below their chin (Fig. 5.1). It is also helpful to always shoot the images in the same sequence. If an image is obviously flawed, simply delete it and retake it. If an image is of questionable quality, take several copies. Review them all on a large monitor, and select the best to retain. The best way to obtain a great final image is to start with excellent images at the time of capture. At the end of the day’s shooting, the images are copied from the memory card to an external hard drive, and then processed using one of several software programs (Fig. 5.2). The author’s personal preference is to use Adobe Lightroom for the vast majority of routine work, with Adobe Photoshop used for certain specific tasks such as deliberate image modification. Other packages such as Capture One, Photo Mechanic, or Perfect Browse can also be used. It is important to develop a folder structure and naming conventions to keep the images neatly organized and easily accessible. The author’s recommended method is to store the RAW images in a master folder, and create individual folders for each patient, named “Lastname, Firstname, Record Number–operation.” The images are renamed with the patient’s name and the image series, e.g., “Lastname, Firstname, Record Number–Rhinoplasty Series Image 1.” Institutional policies on record-keeping and patient identifiers should be respected. Keywords can be added to the metadata to facilitate later searches for specific images. Finally, labels can be applied to images for a teaching file or other special use, and duplicate copies of selected images can be placed in an “Interesting Images” folder.

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49

Fig. 5.1 Patient ID placard in use

Fig. 5.2 Behind-the-scenes view of postprocessing

5 – Postprocessing and Digital Asset Management

50 As medical photographs exist for accurate documentation, editing of their content is not only forbidden, but also counterproductive. However, certain processing of the image is required, including careful adjustment of global parameters such as brightness, contrast, white balance, and saturation, with caution not to introduce errors or inaccuracies (Fig. 5.3). A properly calibrated monitor is required. The sliders in the Lightroom “Basic” panel can all be adjusted small amounts as needed, but with proper camera and light setup, there should be little need for this. A small amount of sharpening and automatic lens profile corrections should be applied. The image can be cropped and straightened if needed, and it is often helpful to shoot the image a bit wide and then crop to the exact anatomic boundaries specified. Special effects filters are not to be used, nor is localized editing such as blemish removal or dodging and burning. Once the images have been optimized in Lightroom, they are saved as maximumquality JPEGs in the patient’s folder and can be printed if desired. If using Lightroom, a great time-saver is the use of an Import Preset. All of the commonly used settings can be saved and automatically applied to all images as they are ingested into one’s catalog. This has the added advantage of producing standardized results. Similarly, presets can be developed for almost any function of the application and can facilitate essentially any repeated task. Color management is an incredibly complicated topic to master, but the basic concept is to maintain accurate depiction of colors throughout all steps of image creation, processing, and display. This must be maintained across platforms and during subsequent examinations, so as not to confuse poor color calibration for subtle anatomic changes. In the postprocessing setting, this means the use of standardized color profiles and calibrated display monitors. Several tools exist to perform this automatically, but similar results can also be obtained manually.

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51

Fig. 5.3 Comparison of (a) straight from camera and (b) properly processed image

5 – Postprocessing and Digital Asset Management

52 In contrast with the rigid editing rules mentioned earlier, some physicians prefer to deliberately modify images to simulate the effect of planned surgery (Fig. 5.4). The Liquify and Warp tools within Adobe Photoshop can be used for these purposes. If this is to be done, the image should be clearly annotated as edited and separated from the documentary images so that confusion does not occur. Use caution when prototyping cosmetic changes in Photoshop, as it is generally far easier to alter a photograph than to alter a patient’s anatomy, and many things that are easy in Photoshop are impossible with even the best of surgery. It is imperative that the image library be backed up frequently, regularly, and securely. Several automated backup systems exist and each has advantages and disadvantages that are beyond the scope of this book. The most important considerations are security and reliability, especially in the current regulatory and medicolegal environment. At minimum, three copies of the data should be maintained: the main data or master; a second copy backed up locally on a regular basis; and a third copy kept off-site in case of catastrophic incidents. When presenting images, the image should initially be presented without a watermark or annotations, with any annotated or modified images following on a subsequent slide. A 4k monitor’s resolution is 3,840 × 2,160 pixels, so higherresolution images can be safely downsized to save space. Keep high-resolution copies of all the images for the presentation in a separate folder, and as a backup it can also be helpful to make large prints of any key images.

5.2

Copyright and Digital Rights Concerns Digital photographs are unfortunately very easy to misappropriate, and many photographers fear that any image that is displayed online is only waiting to be stolen. Current digital rights management software offers limited or no protection against theft. Images are automatically considered copyrighted by the photographer at the moment that they are taken, but enforcement is difficult unless the copyright is registered with appropriate governmental offices, which can be quite cumbersome. A simple practice to offer some protection is to include a copyright notice in the metadata of the photograph. Many photographers place a visible watermark over a portion of their image. While these will reduce casual theft of images, neither method is sufficient against a savvy, dedicated thief, who can remove even the most tenacious of watermarks and strip the metadata within a few minutes. In the event that a digital theft is discovered, consider immediate consultation with a lawyer experienced in intellectual property law.

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53

Fig. 5.4 Deliberate image modification: (a) before and (b) after

5 – Postprocessing and Digital Asset Management

54 The offending party can be contacted and asked to remove the image, using provisions from the Digital Millennium Copyright Act, but it can be difficult or prohibitively expensive to secure payment of damages or other sanctions. As of this writing, several subscription-based services have emerged that assist photographers both in registering their photographs with the U.S. Copyright Office and in recovering damages when an infringement occurs. It is too early in their history for the authors to judge their efficacy; however, it is a development worth following.

5.3

Special Considerations for Videography and Endoscopy For endoscopic recording and archive, there are dedicated image archive and management products available, either integrated with image towers or as stand-alone systems, with cost and functionality concerns to both that are beyond the scope of this book. Mixing brands of endoscopic components is sometimes possible but can create logistical difficulties and should be avoided if possible. Video file formats are surprisingly variable and have confusing associated terminology. The term high definition (HD) is applied to several formats: 720p, 720i, 1,080p, and 1,080i. The numeric indicator in these formats reference the vertical digital pixels of the image, resulting in a resolution of 720 × 1,080; and 1,080 × 1,920. The “p” versus “i” designator refers to progressive scan versus interlaced. Progressive scan requires higher bandwidth but results in better image quality on modern monitors, whereas interlaced displays better on older cathode-ray-tube monitors. Progressive scan is also more amenable to frame grabs, although software can be used to deinterlace images with adequate results. Some medical video systems deviate slightly from the above HD standards, resulting in difficulty with cross-platform interoperability. While 1080p produces high-quality images for display or later review, the storage requirements may necessitate switching to a lower bandwidth format such as 720i. This is accomplished by two common methods: downscaling, where the video signal is converted to a lesser format after capture but before recording, and transcoding, where the image is altered after it is recorded. Both methods are lossy, and subsequent upscaling is not possible, so if possible, retain all images in the highest-quality format available. Because of the file size and processing

5 – Postprocessing and Digital Asset Management

55 limitations of most HD recording platforms, video is typically recorded and archived in a compressed format. There are evolving standards for video compression (or encoding). The most common format today is H2.64/mpeg 4, but the newer H2.65 provides a higher-quality image at a lesser file size, but is less widely used. Video encoding and compression requires proprietary software that is not always interoperable, although newer software packages offer more flexibility in this regard. It is a critical step in making a decision about purchasing a recording platform and configuring it for a particular format to determine if the video is viewable when exported onto other computers. Some archive solutions offer export in alternate video formats, or “transcoding.” This generally adds another layer of lossy compression that may adversely affect the image quality. Other factors in configuring an archive/recording format are key frames and compression rates. These have significant effects on quality and “scrubbing” characteristics of the archived video, which is critical in medical media. Similar to the postprocessing for still image described in this chapter, endoscopic recording systems sometimes offer configuration parameters for image quality (i.e., contrast, hue, brightness). These settings should be handled with subtlety and consideration for how the image displays outside the recording system monitor. Obtaining stills from video can be accomplished as frame grabs either at the time of capture or during subsequent review. Both methods, when properly applied, can produce excellent results with minimal compression artifact, but the latter method allows the clinician to select the optimum frame from several adjacent ones. The format of a recorded still image is variable, but RAW format is not typically an option, since the image is being acquired from an already compressed digital video stream and not directly from the camera sensor. Common file formats such as JPEG and PNG are supported, but generally with minimal control over compression amount. A final consideration when selecting a video recording solution is the source of the image being acquired, as different endoscope types/methods (flexible fiber, distal chip, rigid, stroboscopic) provide their own challenges for optimizing the recorded image. Paradoxically, flexible fiber scopes display better on standard-definition video. Distal-chip scopes produce superlative images, but the proprietary connectors and integrated scope/camera limit recording options. Stroboscopic video output is the same as that of a standard endoscope, provided the light is synchronized properly. All of the above concerns should be addressed with vendors when selecting an endoscopic system.

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6

Smartphones and Telemedicine

Fawn Hogan

Summary This chapter discusses the emerging use of mobile photography in the world of medicine. It provides advice on optimizing image quality as well as on proper use of smartphone capabilities in the context of security, Health Insurance Portability and Accountability Act compliance, and patient privacy. Best practices for image sharing, security, and storage are proposed.

Keywords HIPAA, Health Insurance Portability and Accountability Act, image quality, mobile photography, privacy, smartphone, security, telemedicine

6.1

Smartphones and Telemedicine Optimum-quality medical photographs require meticulous attention to photographic equipment and use of studio techniques. However, this is not always feasible and there are many times when a quick photograph from a smartphone is far superior to not getting a shot at all, speaking to the adage that “the best camera is the one that’s with you.” Additionally, almost all current devices also have video capability, which is highly useful for communicating a clinical situation rapidly. Smartphones also excel at image sharing between colleagues, caregivers, patients, and doctors, although this raises several potential security concerns.

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58 Smartphone imaging technology is still rapidly advancing at the time of this writing. Because of this, it is recommended to always use current-generation technology for best results. When choosing a smartphone, consult multiple independent reviews, compare sample images, and, if possible, test the device under real-world conditions. Smartphone cameras lack most manual controls, and have a wide range of different capabilities and features in terms of lens, resolution, image stabilization, and focusing mechanisms. Therefore, understanding your device’s capabilities is important. Regardless of device used, the following principles are critical to optimizing image quality. First, compose images according to the same principles found elsewhere in this book, and using the same image series (Figs. 6.1–6.3). Surgical towels or plain linens can be used to improvise a distraction-free background if needed. Next, ensure the camera lens is impeccably clean, and always give the lens a quick cleaning with a lens cloth before use. This is especially important as phones are commonly carried in bags and pockets without the use of a lens cap. Disable the flash, and ensure that the lighting in the room is bright and even.

Fig. 6.1 Behind-the-scenes view of smartphone photography

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59

a

Fig. 6.2 Comparison of results from (a) D800 versus (b) iPhone

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60

Fig. 6.3 Intraoperative view of facial nerve division repair (iPhone)

6 – Smartphones and Telemedicine

61 When composing images, remaining at least 2 to 3 ft away from the subject will minimize the perspective distortion inherent to the wide angle lens found on most smartphones (typically 28–35 mm equivalent), but will necessitate subsequent cropping of the image. Avoid the use of the in-camera “zoom” feature, which actually crops the image as opposed to changing the focal length; instead, crop the image in postprocessing. Consider the use of add-on lenses, with a goal-effective focal length of 80 to 100 mm. While most smartphones lack true manual control of focus or exposure, on most models the focal point can be set by tapping on the viewfinder, and exposure compensation can be accomplished by dragging left and right on the screen. Use the rear-facing (main) camera instead of the front-facing camera, as resolution can be up to five times better with the former. Remember to steady the camera with both hands and also consider the use of a support such as a table. The shutter speed cannot be manually controlled, so camera shake cannot be controlled as well as with a traditional camera setup. While a tripod is not usually feasible, a bulkier smartphone case can facilitate steadier handholding. It is important not only to master these techniques yourself, but also to share them with patients, nurses, and other caregivers so that they can communicate effectively with you using smartphone technology. It can be helpful as a teaching tool to prepare a small pamphlet with the basic principles.

6.2

Risks and Pitfalls Smartphone photography is not without risks and pitfalls. First, remember that the consent process remains the same with a standard camera or a smartphone. The smartphone must be password protected and able to be remotely erased if stolen or lost. In an ideal system, images would stream automatically to cloudbased, encrypted storage accessible to only approved users, and all uploads and downloads would be secured and encrypted, all of which is HIPAA compliant. Frequent, automatic backup is required. The smartphones would be dedicated devices with administrative locks to prevent misuse of images. Finally, there would be institutional guidance driving the mechanisms of these processes.

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62 This type of robust image management system is largely absent in the current practice environment, and responsibility for all of the above lies with the photographer physician. Sending images via text message, although convenient and widely performed, is considered non-HIPAA compliant as the process is not usually encrypted. Institutional strategies to help physicians navigate these pitfalls are lacking, but the following will help mitigate risk to the physician. Use a dedicated “work phone” as opposed to a personal phone. Ensure the device is passcode protected, do not share the code with others, and change it frequently. Turn off automatic photo sharing or uploading, and only transfer images on demand to encrypted backup systems or directly with other authorized users. Perform frequent manual downloads of images to the main imaging workstation and file images according to the standard organizational structure listed in Chapter 5.

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7

Approach to the Patient

Scott McCusker

Summary This chapter discusses practical concerns related to interacting with patients during the medical photography process. The informed consent process is detailed, and important considerations for maximizing patient comfort with the photography process are explained. Appropriate attire, hairstyle, and makeup are delineated, as are concerns when dealing with cultural issues and patients from potentially vulnerable populations. Procedures for discussing and sharing images with patients are explicated.

Keywords approach to the patient, clothing, cultural sensitivity, expression, hair, informed consent, makeup, pose, vulnerable populations

7.1

Preparation for the Shoot It is helpful to approach taking photographs as a “surgical procedure” of its own, with its own risk and invasiveness profile. Prior to taking any pictures, the process should be explained, focusing on the rationale for taking pictures as well as the differences between artistic portraiture and medical photography. While photographs of the head and neck typically do not require the patient to disrobe, they still have the risk of making the patient feel very vulnerable and exposed, especially as they are not allowed to hide behind a mask of a flattering pose, expression, and lighting. Additionally, while the patient’s identity is often hidden in medical photographs of the body (by framing so that the face is not visible), this is not possible with photographs of the face. In the past, many have advocated use of black bars over the eyes, or selectively blurring certain features.

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64 This is not recommended as it not only fails to obscure the patient’s identity, but also distracts from the purpose of the image and can obscure useful landmarks and relationships. It is often useful to warn the patients in advance of the visit that you will be taking photographs, or to schedule a separate visit just for that purpose (Fig. 7.1). Give yourself and the patient enough time to be comfortable and not be rushed, and to ensure that the equipment is functioning properly prior to and periodically during use. Most patients are very cooperative and willing to have their photograph taken. However, this may not be true for certain populations such as children, the elderly, or those with disabilities. In the case of the uncooperative child, it is probably better to take suboptimal images with a minimum of fighting as opposed to struggling for “perfect” pictures while angering the patient, their family, and the photographer in the process. For most images, the patient can either sit or stand, but it is usually easiest and most comfortable for both the patient and the photographer to sit on rolling, swiveling stools. If a chair with a back is used, ensure that it is of low profile, such that it does not appear within the image.

7.2

Consent and Image Sharing Informed, written consent should always be obtained, and how the images will be used, shared, and protected must be discussed. A separate photography consent form is best, and it is highly recommended to have a lawyer from your institution’s legal team review the consent form prior to use. If a patient objects to any terms of the consent form, they can be selectively lined out. This most often occurs with patients who do not want their images shared with other physicians or publications, and the patient’s wishes in this regard must be respected. If a patient completely refuses to consent, or wants the critical elements of the consent lined out, their photograph should not be taken and if necessary they should be referred elsewhere for care.

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65

Fig. 7.1 Discussing the planned photo shoot

Great clinical images beg to be shared, but this must be done carefully and respectfully. The patient’s name should never be attached to the image, but given the subject matter of head and neck photography their identity is readily visible. While the consent obtained above allows photo sharing, it is courteous to tell the patient if their image actually will be shared, especially if this is commercial or advertising use. Many patients are flattered to have their image used in such a manner, but this is far from universal.

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66 7.3

Wardrobe and Makeup It is best if patients wear no or minimal makeup, so that the underlying facial features and skin quality can be fully appreciated. However, this is not always practical and for many patients it is almost unquestionable to be seen without makeup. If the patient chooses to wear makeup, they should be instructed to at least do their makeup the same way each time they are photographed. Hurried removal of makeup immediately prior to photographs is not recommended, as it not only angers the patient unnecessarily, but also can cause skin redness. The patient’s clothing and accessories should be either repositioned or removed as necessary so as not to appear in the frame (Fig. 7.2). While in many cultures it is common for the head and neck to be uncovered, it is important to be sensitive to other cultural practices, and to use a chaperone if the situation warrants, even with a fully clothed patient. Long hair should be pulled up so that the neck and hairline are visible. Glasses should be removed.

7.4

Pose and Expression Most medical photographs of the face call for a neutral expression, but it can also be useful in some situations to have the patient perform a variety of expressions, such as to demonstrate cranial nerve function. Many people have a tendency to smile or turn their head when they see a camera, so some coaching can be necessary. While holding the camera, the photographer’s face is largely hidden from the patient, and sometimes it is useful to put down the camera and demonstrate the desired pose to the patient, especially for more unusual or unfamiliar poses.

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b Fig. 7.2 Comparison of (a) distracting elements versus (b) proper composition

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68 7.5

Timing of Photographs Photographs should be taken preoperatively and postoperatively at a minimum. The “final” photographs should delayed until at least 6 to 12 months postoperatively, once healing is truly complete, but it is also useful to take earlier photographs to track the healing process (Fig. 7.3). Photographs should also be obtained immediately if any complications occur, and can be used to track progression of diseases.

7.6

Printing and Reviewing Images with Patients Patients will often request a copy of their photographs, or will want to review the images with their physician. The easiest approach is to make a disc with digital copies of all the images. Reviewing the images with the patient is a powerful communication tool, and usually best done with large-sized printouts (e.g., 8 × 10 in) and the use of a stylus. Adequate results can be obtained by making your own prints, but for finest-quality results the best approach is to use a dedicated photo print laboratory and an experienced photo print technician.

7.7

Rare Diseases and Unusual Clinical Situations If a clinical scenario arises in which the photographic series from this book are inadequate, it is important to take not only the standard views, but also as many supplemental views as are required to fully depict it and aid its understanding for other physicians. If this occurs, please contact the authors of this book so that future editions can be updated accordingly. Consider also taking brief videos from several different angles, especially if the disease affects the function or motion of any structure.

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Fig. 7.3 Comparison of (a) postoperative day 7 versus (b) 6 months postoperation

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8

Intraoperative Photography

Scott McCusker, Fawn Hogan

Summary This chapter discusses special techniques required to safely obtain useful clinical images in the constrained environment of the operative theater. Sterility concerns are discussed, with attention to techniques for surgeons taking pictures and for medical photographers. Appropriate camera settings and use of supplemental lighting are detailed. Image composition and methods to maximize image quality are described. Techniques specific to endoscopy and intraoperative videography are also discussed.

Keywords composition, endoscopy, intraoperative photography, lighting, sterility, technique, videography

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72

Introduction to Intraoperative Photography Intraoperative photographs can be incredibly useful to communicate the exact status of relevant anatomic structures during surgery, or to demonstrate surgical techniques. Several modifications of photographic technique are required for patient safety and optimal image quality (Fig. 8.1). Many surgeons take their own intraoperative photographs, either by preference or by necessity. An extra pair of sterile gloves is used to handle the camera, then removed prior to resuming the operation. Live-view focusing and composition is generally easier. Alternatively, a separate photographer is used, which frees up the surgeon to concentrate on the operation, but requires that the photographer be sufficiently familiar with the operation to take helpful photographs. To avoid contamination, the camera and photographer must be at least 12 in away from the sterile field. This is aided by removing the dangling camera strap, and using a telephoto lens, preferably a zoom for flexibility. With some caution, a macro lens can also be employed using techniques from Chapter 4, but extreme close-ups are generally not possible. As with other medical photographs, an intermediateto-small aperture is required, as is a moderately fast shutter speed.

8.1

Lighting for Intraoperative Photography Supplemental lighting via ring flash produces optimum results. The overhead operating lights should be directed away from the field as the light they produce is harsh, uneven, and poorly color balanced. One exception to this is when working in deep, dark cavities. The overhead lights will require some adjustment but should not be totally removed, as they not only help illuminate the cavity, but also assist with focusing. This may require some trial and error. Additionally, it can be helpful to increase ISO to approximately 800 to 1,000, although this will cause a slight increase in visible noise in the image. Use spot metering mode on the structure of interest.

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Fig. 8.1 Behind-the-scenes view of intraoperative photography

8.2

Optimizing Image Quality Image composition is helped by excellent retraction and hemostasis. Use the minimum number of visible retractors to obtain the desired view, and also use retractors with a matte finish to avoid distracting reflections. If a size reference is

8 – Intraoperative Photography

74 required, a sterile ruler can be placed next to the structure of interest, but also take a picture of the same view without the ruler. Clean blue surgical towels make an excellent backdrop. Ensure that pertinent adjacent anatomic landmarks are visible for reference. Vessel loops, suture packets, or premade background materials can be used to facilitate visualization and increase contrast. Photography from multiple angles is not always possible in the constrained environment of the operating room, but efforts should be made to take standardized photographs as described in the preceding chapters (Fig. 8.2). It can be very helpful for teaching purposes to photograph the operating room setup, such as the positioning or retracting methods, the configuration of the room, or the scrub technician’s back table (Fig. 8.3). Make sure that the instrumentation is clean, well organized, and only relevant items are included in the frame. No people other than the patient should be visible unless it is necessary to the understanding of the image, and if so ensure that photography consent is obtained from them as well. It is also important to ensure photographs do not inadvertently include any identifying information, such as the patient’s name on a pathology label or operating room white board.

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Fig. 8.2 Intraoperative view of revision rhinoplasty

Fig. 8.3 Demonstration of back table setup

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9

Special Considerations for Reconstructive Surgery

Scott McCusker, Fawn Hogan

Summary This chapter discusses additional photographic concerns for reconstructive surgical procedures, including timing of photography, assessment of the premorbid state of the patient, and accurate photographic documentation of structure and function throughout the reconstructive process. Suggested imaging series for several more commonly encountered reconstructive situations are described.

Keywords defect, free anterolateral thigh flap, free fibula flap, free radial forearm flap, function, locoregional flap, pectoralis flap, reconstruction, rib graft, skin graft

9.1

Special Considerations for Reconstructive Surgery The basic principles of photography for reconstructive surgery are the same as for any other medical photography. However, there are some specific concerns at each phase of the reconstructive process that must be addressed to achieve optimum results. For planned reconstructive cases, attempt to obtain photos not only prior to surgery, but also prior to the creation of the defect, and at the true premorbid

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78 state. This will often mean obtaining old photographs, such as from a yearbook or family photo album (Fig. 9.1). Caution is needed in interpreting these pictures, as an artistic portrait from the teenage years is probably not representative of the state of the patient later in life, but it can still offer usable information. Photographs of the defect should be obtained according to the methods presented elsewhere in this book, with attention to accurately depicting not just the cosmetic nature of the defect, but also any functional consequences arising from it. The donor site(s) should also be photographed, with similar attention to form and function. This is especially important with complex reconstructive cases in which donor site morbidity is a larger concern. For multistage procedures, each stage of the repair should be photographed. These photographs can also be used (with appropriate permission) to help communicate with other patients undergoing similar reconstructions, and are especially useful for procedures such as the paramedian forehead flap.

9.2

Photo Series The photo series that follow represent the most commonly encountered reconstructive problems in the head and neck but are far from exhaustive. The principles enumerated can be readily extrapolated to other reconstructive situations as they arise.

9.2.1

Skin Grafting

For small grafts such as full-thickness postauricular grafts, macrophotographs of the donor and recipient sites are sufficient. For larger grafts, also include the entire structure from several angles, such as the entire thigh, and consider views with the joints above and below flexed and extended.

9.2.2

Local Flaps of Head and Neck

Pertinent images from the series in Chapter 8 are sufficient to depict these flaps. For smaller flaps, it is helpful to also take macrophotographs using the techniques from Chapter 12.

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Fig. 9.1 Premorbid state depicted by yearbook photo

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80 9.2.3

Rib Graft

Close-up views of the incision site should be obtained. For patients with pendulous breasts, the patient should use the hand to gently elevate the breast. To demonstrate that the scar does not affect the breast morphology or motion, the entire torso should be imaged with the arms at the sides, hands on hips, and hands on head (Fig. 9.2).

9.2.4

Pectoralis Major Flap

Similar to Rib Graft above, the entire torso should be imaged, with the arms positioned as described. This has the added benefit of demonstrating any diminution in arm mobility as a result of the flap.

9.2.5

Free Fibula Flap

The leg and foot are imaged to just above the knee, from various angles (Fig. 9.3). Both legs should be imaged so that symmetry can be compared. It is also helpful to take pictures not just with the patient standing neutrally, but with alternate flexion and extension of knee and ankle.

9.2.6

Free Anterolateral Thigh Flap

The thigh is imaged to just below the knee, from various angles. Both legs should be imaged so that symmetry can be compared. It is also helpful to image not just with the patient standing neutrally, but also with alternate flexion and extension of the hip and knee. Undergarments may be worn so long as they do not obscure the view of the thigh or distract from the image.

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Fig. 9.2 Torso, anterior, hands at sides

Fig. 9.3 Right lower leg, lateral profile

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82 9.2.7

Free Radial Forearm Flap

The hand and forearm are photographed from various angles, with the forearm alternately pronated and supinated, the wrist flexed and extended, and fingers extended, flexed, and grasping (Fig. 9.4). Symmetry with the contralateral side should be demonstrated, optimally by including both sides in the frame simultaneously. A table covered in blue material can be placed on the patient’s lap to facilitate these views.

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Fig. 9.4 Hands and forearms, fingers spread, palmar

85

10

Face and Neck

Scott McCusker

Summary This chapter presents a comprehensive series of photographic views of the face and neck. The exact settings and all details required to create these images are discussed in depth, and all possible combinations of pose, angle, and expression are explored. Use of appropriate images from these series will allow accurate and thorough documentation of the face and neck for a broad range of applications in general otolaryngology, head and neck oncology, and facial plastic surgery.

Keywords Camera angle, composition, face, focus, image series, neck

Introduction The photographs that follow represent standardized views of the face and neck for use in a wide variety of clinical situations. All were taken with the same equipment and settings: Nikon D800, Micro-Nikkor 105 mm, f/11, 1/125, ISO 100, using the 4-light setup from Chapter 3. Be sure to view the online content available on MediaCenter.thieme.com that includes all referenced images; for brevity and clarity, only one side is depicted but both should be photographed for actual patient use.

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86 10.1

Image Series 10.1.1

Full Face, Frontal

The patient faces directly forward, looking straight ahead (Fig. 10.1). The superior border of the frame is just above the top of the head. The inferior border is at midneck level. An equal border of background is visible on both sides of the frame—the patient is centered exactly. The camera is held at the same level as the center of the face and level in all planes. A neutral expression is used. The head should be level and vertical, confirmed by the height of the medial canthi and the root of the helices, or by a vertical line from the midpoint of the hairline through the nose, philtrum, and midline of the mentum. With any method, caution should be used as most patients have at least some degree of subtle facial asymmetry. The focus point is placed on either eye.

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Fig. 10.1 Full face, frontal

10 – Face and Neck

88 10.1.2

Full Face, Left and Right Oblique

This view is the same as “Full Face, Frontal,” except as noted below (Fig. 10.2). The patient turns their body and head 45 degrees left or right, respectively, looking straight ahead in line with their body. The exact degree of rotation can be confirmed by placing a marker on the floor or wall on which the patient can focus. Many advocate aligning the tip of the nose with the midpupil or the border of the cheek, but this can lead to inconsistency based on the patient’s degree of nasal tip or cheek projection. The focal point is placed on the front eye.

10.1.3

Full Face, Left and Right Profile

This view is the same as “Full Face, Frontal,” except as noted below. The patient turns their body and head 90 degrees left or right, respectively, looking straight ahead in line with their body. Neither the far brow nor eye are visible. Confirm the head alignment with the Frankfort horizontal plane, i.e., a horizontal line through the top of the external auditory canal (porion) and the inferior border of the orbit (orbitale). Use the front eye as the focal point.

10.1.4

Full Face, Left and Right Rear Oblique

These views are the same as “Full Face, Left and Right Oblique,” except the patient turns 135 degrees left or right from the camera as opposed to 45 degrees. Focus on the ear.

10.1.5

Full Face, Rear

This view is the same as “Full Face, Frontal,” except the patient turns 180 degrees from the camera. Focus on the occiput.

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Fig. 10.2 Full face, right oblique

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90 10.1.6

Full Face and Neck, Frontal, Left and Right Oblique, Left and Right Profile, Left and Right Rear Oblique, Rear

These views are the same as the “Full Face” series of views described earlier, but with the lower border just below the sternal notch instead of midneck (Fig. 10.3). The arms and shoulders should be allowed to hang naturally at the sides and the patient should sit straight up, but not stiffly.

10.1.7

Neck, Frontal), Left and Right Oblique, Left and Right Profile, Left and Right Rear Oblique, Rear

These views are the same as the “Full Face and Neck” views described earlier, but with the upper border at the base of the external auditory canal (Fig. 10.4).

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Fig. 10.3 Full face and neck, frontal

Fig. 10.4 Neck, frontal

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92 10.1.8

Neck, Frontal, Left and Right Oblique, Left and Right Profile, Platysma Contracted

These views are the same as “Neck, Frontal, Left and Right Oblique, Left and Right Profile” as described earlier, but with the platysma strongly contracted

(Fig. 10.5). This pose can only be comfortably held for a few seconds, so it is imperative to work quickly.

10.1.9

Neck, Frontal, Left and Right Oblique, Left and Right Profile, Shoulder Shrug, Maximum Flexion and Extension, Left and Right Rotation, Left and Right Tilt, Shoulder Depression

These views are the same as the “Neck” views described earlier, except with the neck and shoulders positioned as described. It is only necessary to perform as many permutations of the above positions and camera angles as contributes to understanding of the patient’s condition, as performing each of them can be quite tedious (Figs. 10.6–10.8).

Fig. 10.5 Neck, left oblique, platysma contracted

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Fig. 10.6 Neck, frontal, shoulder shrug

Fig. 10.7 Neck, left profile, maximum flexion

Fig. 10.8 Neck, frontal, maximum extension

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94 10.1.10

Nose, Close-up, Neutral

The patient faces directly forward, looking straight ahead (Fig. 10.9). The superior border of the frame is at the lower one-third of the forehead. The inferior border is at the lips. The nose is centered exactly left to right. A neutral expression is used, and the patient breathes quietly. The head is held vertically as confirmed by the height of the medial canthi. Focus on the dorsum of the nose.

10.1.11

Nose, Base View, Neutral

The patient faces directly forward, but extends the neck maximally (Fig. 10.10). The photographer is positioned below the nose, angled upward into the alae. The superior border of the frame is a small amount above the nose. The inferior border is the midportion of the upper lip. The nose is centered exactly left to right. A neutral expression is used, and the patient breathes quietly. Ensure that neither patient nor camera is skewed. Proper angulation can be confirmed by the height of the brow or medial canthi. Focus on the columella.

10.1.12

Nose, Close-up and Base View, Sniffing

These views are the same as “Nose, Close-Up and Base View, Neutral,” but with the exception that the patient is instructed to sniff deeply and vigorously as the picture is taken. This will cause many patients to lurch up and back slightly, so some practice is required to maintain proper framing and timing.

10.1.13

Nose, Top Down

The patient faces directly away from the photographer, but extends the neck maximally. The photographer is positioned above the nose, angled downward over the dorsum. The superior border of the frame is a small amount above the nose. The inferior border is the midforehead. The nose is centered exactly left to right. Ensure that both the camera and the patient’s head are level side to side. Proper angulation can be confirmed by the height of the brow. Focus on the dorsum of the nose.

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Fig. 10.9 Nose, close-up, neutral

Fig. 10.10 Nose, base view, neutral

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96 10.1.14

Nose, Tip Support View

This view is the same as either “Full Face, Left or Right Profile,” with the exception that the patient gently compresses the tip of the nose posteriorly with their index finger (Fig. 10.11).

10.1.15

Full Face, Frontal, Eyebrows Elevated, Eyes Tightly Closed, Smiling, Lips Pursed, Frowning, Cheeks Puffed

These views are the same as “Full Face, Frontal,” except that the patient is instructed to assume each of the above expressions sequentially. This will show the function of the various branches of the facial nerve or any asymmetry of facial motion (Fig. 10.12).

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Fig. 10.11 Nose, tip support view

Fig. 10.12 Full face, frontal, eyes tightly closed

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98 10.1.16

Upper Face, Frontal, Left and Right Oblique, Left and Right Profile

These views are the same as the “Full Face” views described earlier, but with the lower border at the infraorbital rim instead of midneck (Fig. 10.13).

10.1.17

Upper Face, Frontal, Brow Elevated, Brow Depressed, Eyes Gently Closed, Eyes Tightly Closed, Looking Up, Looking Down, Looking Left, Looking Right

These views are the same as the “Upper Face” series, but the patient sequentially assumes each of the above expressions. The “Upper Face, Left and Right Oblique, Eyes Tightly Closed” views are can also be obtained.

10.1.18

Lower Face, Frontal, Left and Right Oblique, Left and Right Profile

These views are the same as the “Full Face” views described earlier, but with the upper border at the nasal tip instead of a few inches above the top of the head (Fig. 10.14).

10.1.19

Lower Face, Frontal, Smiling, Lips Pursed, Frowning, Cheeks Puffed

These views are the same as “Lower Face, Frontal,” but the patient sequentially assumes each of the above expressions. The “Left and Right Oblique” views of the same are also of utility.

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Fig. 10.13 Upper face, frontal

Fig. 10.14 Lower face, frontal

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100 10.1.20

Left and Right Ear, Frontal, Oblique, Profile, Rear Oblique, Rear

These views are the same as the “Full Face” views described earlier, but with the upper border just above the apex of the helix, the lower border just below the lowest portion of the lobule, and the respective ear centered left to right in the frame (Fig. 10.15). If the postauricular area must be visualized, the patient can use their hand to fold the ear gently forward (auricle retracted forward). Focus on the center of the auricle.

10.1.21

Scalp, Angled Downward, Frontal, Left and Right Oblique, Left and Right Profile, Left and Right Rear Oblique, Rear

For the frontal view, the patient sits with head and neck in neutral alignment, facing the photographer, who stands and angles the camera downward at approximately 45 degrees (Fig. 10.16). The superior border of the frame is just above the top of the head, and the inferior border is at the radix. The patient is centered in the frame side to side and a small amount of background is visible on either side. Focus on the upper forehead. The remaining views are the same, but with the patient rotated sequentially.

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Fig. 10.15 Left ear, profile

Fig. 10.16 Scalp, angled downward, frontal

103

11

Oral Cavity and Oropharynx

Scott McCusker

Summary This chapter presents a comprehensive series of photographic views of the oral cavity and oropharynx. The exact settings and all details required to create these images are discussed in depth, as are the special techniques required for working within the anatomic constraints of the region. Use of appropriate images from these series will allow accurate and thorough documentation of the oral cavity and oropharynx for a broad range of applications in general otolaryngology, head and neck oncology, and facial plastic surgery.

Keywords anatomy, camera angle, composition, focus, image series, landmarks, oral cavity, orientation, oropharynx

Introduction The photographs that follow represent standardized views of the oral cavity and oropharynx for use in a wide variety of clinical situations. Except as noted below, all were taken with the same camera, lens, and settings: Nikon D800 camera body, Micro-Nikkor 105 mm f/2.8 lens, Sigma EM-140 DG Ring Flash, f/32, 1/125, and ISO 100. A rigid endoscope can also be used for similar results.

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104 11.1

Image Series 11.1.1

Anterior Dentition, Lips Retracted, Frontal

The borders of the frame are the lips, which are retracted bilaterally using a plastic “Smiley” retractor (Fig 11.1). The patient faces straight ahead with the teeth closed gently and without shifting the mandible from a neutral position. Focus on the central incisors.

11.1.2

Anterior and Lateral Dentition, Lips Retracted, Left and Right Oblique

This is the same as “Anterior Dentition, Lips Retracted, Frontal,” but with the patient turned 45 degrees left and right, respectively. Focus on the nearest tooth. By shifting the retractor toward the side closest to the camera, more of the lateral dentition can be visualized.

11.1.3

Anterior and Lateral Dentition, Lips Retracted, Left and Right Profile

This is the same as “Anterior Dentition, Lips Retracted, Frontal,” but with the patient turned 90 degrees left and right, respectively. Focus on the nearest tooth. The retractor should only be used on the side closest to the camera so that more of the lateral dentition can be visualized.

11.1.4

Lower Face, Maximum Mouth Opening, Frontal, Left and Right Oblique, Left and Right Profile

This series is the same as “Lower Face, Frontal, Left and Right Oblique, Left and Right Profile” from Chapter 10, with the exception that the mouth is opened maximally. The 4-light balanced setup is used, and the settings are f/11, 1/125, and ISO 100.

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Fig. 11.1 Anterior dentition, lips retracted, frontal

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106 11.1.5

Left and Right Buccal Mucosa

The patient turns 30 to 60 degrees to the side and opens the mouth maximally. The closer lip is retracted for visualization. Focus on the center of the buccal mucosa (Fig. 11.2). The borders of the frame are the teeth. Endoscopic visualization with an angled endoscope is often superior.

11.1.6

Anterior Floor of Mouth

The patient faces the camera, opens their mouth maximally, and then touches the tongue to the roof of the mouth. The camera is then angled downward to image the area of concern. The focal point is the center of the floor of the mouth. The borders of the frame are the teeth.

11.1.7

Oral Tongue, Frontal, Left and Right Oblique

The patient faces straight toward the camera, then 45 degrees left or right, respectively, and opens their mouth maximally with the tongue in a neutral position. The camera is angled downward with the focal point on the center of the visualized portion of the tongue. The border of the frame is the teeth.

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Fig. 11.2 Right buccal mucosa

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108 11.1.8

Oral Tongue, Frontal, Protruded, Left and Right Deviated, Elevated

These views are the same as “Oral Tongue, Frontal” described earlier, but with the tongue in the positions listed above as opposed to neutral (Fig. 11.3).

11.1.9

Left and Right Retromolar Trigone

This area is difficult to fully visualize by any method. The jaw is opened maximally and the camera is angled slightly downward. A slightly oblique view usually allows better visualization than straight on. Retraction of the lip and tongue can be helpful in some patients. Endoscopic visualization is generally superior, especially if an angled endoscope is used.

11.1.10

Anterior Palate

The patient faces the camera with the mouth maximally open and the neck extended maximally. The camera is angled upward with the focal point on the center of the hard palate. The borders of the frame are the teeth anteriorly and the soft palate posteriorly.

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Fig. 11.3 Oral tongue, frontal, protruded

11 – Oral Cavity and Oropharynx

110 11.1.11

Soft Palate and Posterior Pharynx

The patient faces the camera with the mouth maximally open and the palate in a neutral position (Fig. 11.4). The tongue can be retracted if it obstructs full visualization. Focus on the uvula. The borders of the frame are the teeth, tongue, and proximal palate. Close-up views of the tonsils/tonsillar fossae can also be obtained as needed.

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111

Fig. 11.4 Soft palate and posterior pharynx

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12

Sinuses and Nasopharynx

Erik Weitzel

Summary This chapter presents techniques for optimizing image quality for nasal endoscopy, including a comprehensive series of photographic views of paranasal sinuses, nasal cavity, and nasopharynx. All details required to create these images are discussed in depth. Use of appropriate images from these series will allow accurate and thorough documentation of the region for general otolaryngologists and rhinologists alike.

Keywords endoscopy, ethmoid sinuses, Eustachian tube, frontal sinus, image quality, maxillary sinus, nasopharynx, sinus, sphenoid sinus.

Introduction Photography of the paranasal sinuses and nasopharynx requires the use of endoscopic techniques given the nature of the anatomy. As discussed in Chapter 2, there are three primary endoscope choices: 14-cm rigid, flexible fiberoptic, and chip-tip flexible endoscopes. The use of fiberoptic endoscopes is not recommended because of the inferior image quality in comparison with the other options. Unless otherwise specified, use a rigid 0-degree endoscope for the best image quality. Reserve angled rigid scopes for visualization around corners. While the techniques discussed in this chapter refer primarily to clinical examinations, they can be readily adapted to intraoperative use as needed.

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Optimizing Image Quality Optimizing image quality for endoscopy requires broad-spectrum lighting, red spectrum resolution, proper exposure, endoscope tip cleanliness, and lens viability. Different light sources produce different spectra of radio frequency energy, and light that appears “white” to the naked eye is of highly variable character. This can lead to poor display of certain colors, most commonly in the red spectrum, which is the most important for endoscopic imaging as the sinuses and their contents fall almost entirely in this range. It is critical that lighting supplied for endoscopy has a wide spectrum with significant broadband components in the reds, and that the camera chip and display monitor all be tuned to achieve the highest degree of red resolution. With regard to lighting, light intensity falls via the “inverse square rule”; thus, structures closer to the endoscope tip are exponentially brighter than those farther away. The autoexposure feature on most medical-grade imaging systems does not handle this well, resulting in blown highlights on closer structures and more distant objects being masked in shadow. Trial-and-error manipulation of image settings can sometimes improve exposure. The endoscope tip must be fastidiously cleaned throughout the procedure. Meticulous hemostasis is paramount. Heat from the light is transmitted asymmetrically to the tip of the endoscope. Blood tends to cake on to the light transmitting fibers before the receptor fibers are affected. Thus, the light carrying capacity of the endoscope deteriorates first, and then the image becomes blurry. A moist cotton cloth and/or micro instrument wipe can be used to aggressively clean off debris throughout a procedure. A gentle surfactant or mucus can be subsequently applied to limit fogging of the lens once placed into the nasal cavity, and scope warmers also limit fogging. While devices such as the Medtronic Endoscrub can flush gross blood from the tip of the endoscope during surgery, small amounts of blood accumulate between the lens and device, so the Endoscrub must be removed and cleaned prior to producing production quality images. For rigid endoscopes, the quality of the lens elements is important for eventual image quality. Most endoscopes contain three friction fitted lenses within the shaft. Light refraction will accommodate for minor problems within any one of the lenses; however, image resolution deteriorates markedly across the image with any lens defect. A special inspection tool is available from company representatives to check lens quality.

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115 Images should be displayed at the highest resolving capacity of the monitor. Cameras equipped with an aperture control should be utilized with all endoscopic pixels available for visualization (full viewing circle visible on screen) due to the fish-eye nature of the viewing and the need for parallax to create depth perception. Additionally, this avoids inadvertent trauma to mucosa at the periphery of the field of view. Magnification of the image is appropriate during detailed surgical interventions such as pituitary adenoma resection but then should be returned to full pixel view as soon as possible. Flexible fiberoptics are best viewed with the aperture maximally reduced to minimize the honeycomb effect. Coaxial rotation is a final critical element in viewing. With circular equipment, it is quite easy to find that true anatomical superior is off-axis with viewing superior. Patient safety and quality in imaging demand that both anatomical angles and viewing angles are aligned.

12.2

Image Series There is no consensus on the standard static views of the paranasal sinuses. Useful views of the paranasal sinuses must show relevant anatomic landmarks, be oriented properly with respect to the vertical, and allow resolution of critical pathology. The critical presurgical landmarks include the inferior turbinate, axilla of the middle turbinate, superior turbinate, and choanae. In postsurgical patients, the following landmarks are also used: the planum sphenoidale, choanae, nasal floor, frontal process of maxilla, orbit, and fovea ethmoidalis. For many of the views that follow, only some of the borders are critical, and the remaining borders are allowed to follow based on the field of view of the endoscope. Analogous techniques can be also used for views of extended endoscopic procedures of the anterior skull base.

12.2.1

Anterior Nasal Cavity, Left and Right

The inferior border is the nasal floor; the superior border is at or just above the head of the inferior turbinate. Laterally, the insertion of the inferior turbinate is visible, and medially, the cartilaginous septum and maxillary crest are included. In the background, portions of the middle turbinate are visible.

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Internal Nasal Valve, Left and Right

This view is the same as “Anterior Nasal Cavity, Left and Right,” except angled upward so that the superior limit is the internal nasal valve. The entire scroll area should be visible. Focus on the articulation between the septum and upper lateral cartilage.

12.2.3

Sphenoethmoidal Recess, Left and Right

This view captures the posterior drainage pathway that drains the posterior ethmoids and sphenoid sinus. The inferolateral border is the root of the inferior turbinate, and the septum is the medial border. The superior turbinate occupies most of the image superolaterally. Ideally, the sphenoid ostium is captured in the image for perspective, but may not be visible in some patients based on their superior turbinate configuration.

12.2.4

Choana, Left and Right

The inferior border is the soft palate; the superior border is the superior aspect of the choana mucosa. Laterally, the view should include the entire torus tubarius, and medially, the posterior aspect of the septum should be visible. The inferior and middle turbinate may block views of the choana; thus, maximal decongestion of the nasal turbinates is required.

12.2.5

Middle Meatus, Left and Right

Use a 30-degree rigid scope angled laterally or a flexible chip-tip scope. The inferior border is the uppermost portion of the inferior concha and the superior limit is just above the axilla of the middle turbinate. Laterally, the view should include the entire frontal process of the maxilla from the inferior turbinate to the axilla. The medial border is the septum.

12.2.6

Nasopharynx

Inferiorly, the soft palate is just visible; superiorly, the adenoid remnant or nasopharyngeal roof is evident. Ideally, both Eustachian tube orifices are visible, although this may not be possible in patients who have not had a posterior septectomy; in that case, left and right views may be obtained.

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117 12.2.7

Maxillary Ostium, Left and Right

A 30- or 70-degree rigid scope is used (Fig. 12.1). The uncinate must be surgically removed to obtain this view. The ostium is centered and viewed as closely as possible. A clearly visible common drainage pathway permits orientation of the image.

12.2.8

Maxillary Sinus, Left and Right

A 30- or 70-degree rigid scope angled laterally is placed at the middle meatus following a middle meatal antrostomy. There is high risk of unacceptable coaxial rotation in this image. The orbital roof must be aligned with the superior aspect of this image. The superior border is the orbital floor, inferiorly the root of the inferior turbinate, and medially the middle meatus. The lateral border is determined by the field of view. If the deepest recesses of the sinus must be visualized, a flexible scope can be inserted into the sinus proper, or a rigid endoscope can be passed into the sinus via a transseptal/transcanine fossa approach.

Fig. 12.1 Maxillary ostium, left

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118 12.2.9

Anterior Ethmoids and Frontal Sinus Outflow Tract, Left and Right

A 30- or 70-degree rigid endoscope angled upward is used following anterior ethmoidectomy with or without frontal sinusotomy (Fig. 12.2). The most superior aspect of the image should include the entire frontal ostium with an apparent frontal process of the maxilla for lateral orientation. The axilla of the middle turbinate will not be visualized in this image. The lateral border is the lamina papyracea, and the medial and inferior borders follow based on the field of view.

12.2.10

Frontal Sinus post-Draf III Procedure

This view can only be obtained in patients with a previous Draf III procedure

(Fig. 12.3). The inferior border includes the junction of the septum, cribriform plate, and middle turbinates (frontal “T”). The anterior limit includes the frontal beak remnant showing the smooth mucosal transition from nasal bone to frontal bone. The lateral borders are the frontal sinus neo-ostium.

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Fig. 12.2 Anterior ethmoids and frontal sinus outflow tract, left

Fig. 12.3 Frontal sinus post-Draf III procedure

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120 12.2.11

Ethmoidectomy, Complete, Left and Right

A 0- or 30-degree endoscope angled upward can be used (Fig. 12.4). The frontal ostium should orient the viewer anteriorly. The lateral border is the lamina papyracea, the middle turbinate is the medial border, and the inferior border follows based on the field of view.

12.2.12

Sphenoid Sinus, Left and Right

A sphenoidotomy must have already been completed (Fig. 12.5). The superior border is the skull base and planum sphenoidale. The inferior border is the floor of the sphenoid sinus. The lateral border is the lateral wall of the sphenoid, and the medial border follows based on the field of view or is the intersinus septum. If a combined sphenoidotomy has been performed, the bilateral lateral walls are visible as lateral borders of the frame. Angled or flexible endoscopes can also be used to obtain close-up views of the lateral sphenoid anatomy, focusing on the relation of the carotid, optic nerve, sella, and sphenoid roof. In this instance, it is helpful to have a clearly defined optico-carotid recess for orientation of optic nerve and carotid.

12.2.13

Lacrimal Sac, Left and Right

Use a 30-degree endoscope angled superolaterally. The lacrimal sac is dissected fully, then centered in the field of view, with the superior, lateral, and inferior borders of the frame capturing mucosa over the frontal process of the mucosa and uncinate.

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Fig. 12.4 Ethmoidectomy, complete, right

Fig. 12.5 Sphenoid sinus, right

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13

Imaging of the Upper Airway and Larynx

N. Scott Howard, Scott McCusker

Summary This chapter presents techniques for optimizing image quality for endoscopic imaging of the larynx and surrounding structures, including still photography and videography. A standard series of photographic views is presented, followed by a discussion of standard video techniques for laryngeal imaging, and then advanced techniques including videostroboscopy, videokymography, and high-speed digital imaging. Appropriate use of these images and techniques will allow accurate and thorough documentation of the region for general otolaryngologists and laryngologists alike.

Keywords endoscopy, high-speed digital imaging, laryngoscopy, mucosal wave, videokymography, videostroboscopy, vocal cords

Introduction Medical imaging of the upper airway is significantly different from other head and neck imaging in that it not only requires use of endoscopic techniques, but also is highly dependent on the use of video. Similar to other endoscopic applications in the head and neck, angled rigid scopes and flexible distal-chip laryngoscopes produce the best results for most situations, and fiberoptic scopes should be avoided if possible due to their low image quality. For many patients, the increased comfort of flexible transnasal endoscopy with a distal-chip scope outweighs the slight decrease in image quality compared with rigid scopes as it

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124 also allows natural phonation not possible with per-oral techniques. However, rigid examination remains an excellent tool to visualize the laryngeal mucosa. An important concern specific to the larynx is the ability to rapidly switch between different light sources such as xenon, strobe, and narrowband imaging.

13.1

Image Series Still photographs are best obtained as frame grabs from careful review of video, and should be used sparingly, reserving the bulk of one’s attention for the more important review of the motion of the larynx and related structures. The photographs alongside are from a single healthy volunteer using the same equipment: Olympus Visera Elite OTV-S190 video processor, the CLV-S190 Xenon light source, and ENF-VH video rhinolaryngoscope.

13.1.1

Home Position

A flexible endoscope is placed through the nose, with the tip at the level of Passavant’s ridge, also known as the velopharyngeal isthmus. In this position, upward/posterior movement of the palate will obscure the view of the larynx. This position is ideal to get a general look at the health of the posterior oropharynx and a distant look at the larynx as well as an ideal starting position for procedures done to include transoral injection of the vocal fold and fiberoptic endoscopic evaluation of swallow. Note that the vocal folds form a “V” shape with the anterior commissure at the bottom of the screen. As such, the right vocal fold appears to the left and the left vocal fold appears on the right. Protruding the tongue and/or jaw jet can improve visualization of the vallecula.

13.1.2

Larynx, Cords Adducted and Abducted, Cheek Puffed/ Valsalva

This position fills the available view with the entire laryngeal structure and surrounding pharyngeal wall including the epiglottis, aryepiglottic folds, and arytenoids (Fig. 13.1). Obtain views with the vocal cords alternately fully abducted and adducted, as well as a view while the patient performs a valsalva maneuver to open the hypopharynx/pyriforms. Light intensity and gain of the capture equipment may need to be fine-tuned manually for proper exposure.

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Fig. 13.1 (a) Larynx, cords adducted. (b) Larynx, cords abducted

13 – Imaging of the Upper Airway and Larynx

126 13.1.3

Vocal Folds, Close-Up

The endoscope is advanced so that the tip is just above the vocal cords and they fill the field of view (Fig. 13.2). Application of topical lidocaine may be required to obtain this view.

13.1.4

Subglottis and Proximal Trachea, Carina and Mainstem Bronchi

The scope is now advanced through the vocal cords to perform a “transnasal tracheoscopy” or TNT. This necessitates use of topical lidocaine applied to the vocal folds. This can be accomplished through transtracheal injection or dripped on the vocal folds via transoral or through a variety of methods through a ported scope. Obtain images from just below the vocal cords as well as just above the carina at a minimum, and additional close-up views of any lesions encountered.

13.2

Video Images of Laryngeal Anatomy Dynamic imaging of the larynx is conducted from the same position as the “Larynx, Cords Adducted” still photograph, using a standardized examination sequence designed to maximize visualization of the mucosal wave and any potential derangements of it. The complex vibratory patterns of the vocal cords are invisible to the naked eye under normal conditions, but with proper examination techniques can be visualized in a repeatable manner, allowing accurate diagnosis and treatment. Key parameters to note are the amplitude, phase difference, symmetry, and velocity of the lateral vocal fold lip movement and the secondary wave (the primary wave is not visible from above the larynx). A full discussion of the nature of the mucosal wave is beyond the scope of this text. The patient begins with quiet breathing, then sniffing, followed by prolonged phonation of /i/ or /ah/. Next the patient is asked to alternate short /i/ with sniffing, then to say rapid alternating sounds such as “puh-tuh-kuh.” Additional helpful maneuvers include smooth changes of pitch (glissando), prolonged /i/ at high, intermediate, and low pitches, and unloading via gentle humming. The patient can also be asked to recite a standardized passage of text such as the “rainbow passage.” It can be helpful to keep a placard next to the video monitor with the examination sequence listed. Standard examination of the larynx is conducted with incandescent “white” light. Subtle details of the mucosa and underlying vasculature can be amplified

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Fig. 13.2 Vocal folds, close-up

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128 by use of narrowband imaging. This uses spectrum-limited light (i.e., 440 and 515 nm) as opposed to full-spectrum light. The effect is to highlight small variations in hues of red. When activated, the mucosa of the larynx appears translucent with blood vessels on and beneath the mucosal surface visible, and can aid detection of premalignant lesions.

13.3

Considerations for Advanced Video Techniques To see the mucosal wave itself, the “Vocal Folds, Close-Up” position is used, and special techniques such as stroboscopy, high-speed digital imaging, or videokymography are required. The light sources used for these have differing color temperatures, so white balancing is required whenever switching modalities. Stroboscopy (aka videostroboscopy) is based on an optical illusion in which rapid motion appears to be slowed down by use of rapidly flashing pulses of light, but captured at normal frame rates. This can then be displayed as “slow-motion” video or a tiled sequence of successive frames (Fig. 13.3). This requires regular periodic vibration that is not always present in vocal disorders, and does not allow analysis of cycle-to-cycle variations. However, stroboscopy is relatively cheap and easy to perform, and can produce excellent results in the majority of patients. In contrast to stroboscopy, high-speed digital imaging uses continuous lighting, but very rapid frame capture rates (2,000–4,000 frames per second), which is then displayed at the normal 30 fps, producing a slow-motion effect. This allows accurate visualization of both aperiodic vibration and cycle-to-cycle variation, but the cost of these systems as well as their marginal added utility over stroboscopy limit their use in most clinical situations. Videokymography is similar to high-speed imaging in that it can capture up to 8,000 images per second, but does so by only scanning one transverse line (perpendicular to the vocal fold) as opposed to the entire field of view. Therefore, it requires significantly less bandwidth. The resulting lines are tiled so that successive open/close cycles at that level can be visualized. Videostrobokymography is a similar technique but uses lines extracted from the stroboscopic video image as opposed to high-speed capture. However, just like stroboscopy, this is only an artificial representation of the actual mucosal wave. Depth kymography is a variation of this technique but targeted at the lower lip of the vocal cord so that the primary mucosal wave can be visualized.

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Fig. 13.3 Stroboscope montage

131

Appendix: Suggested Photographic Series for Selected Situations Introduction It is important to use a standardized series of photographs for commonly encountered clinical scenarios, as this allows the best opportunity for longitudinal follow-up as well as comparison with different patients in similar circumstances. Photographs are not necessarily mandatory for each of the following conditions, but if photographs are taken, the series below should be implemented at a minimum. The author’s opinions of required views are italicized; the remaining supplemental views are for use as needed for the clinical situation. Add additional nonstandard views as needed if they will help in understanding the condition, and also consider taking brief videos in situations where understanding motion is important.

A1.1

Image Series A1.1.1

Rhinoplasty

Full face, frontal; full face, left and right oblique; full face, left and right profile; nose, close-up and base view, neutral and sniffing; nose, top down; nose, tip support view.

A1.1.2

Nasal Reconstruction

In addition to rhinoplasty series, consider the following based on nature of reconstruction: scalp, angled downward, frontal; upper face, frontal; upper face, left and right oblique; upper face, left and right profile; left and right ear, frontal; left and right ear, oblique; left and right ear, profile; left and right ear, rear oblique; left and right ear, rear; torso, arms neutral; torso, hands on hips; torso, hands on head; inframammary fold, neutral; inframammary fold, breast elevated.

Appendix: Suggested Photographic Series for Selected Situations

132 A1.1.3

Otoplasty

Full face, frontal; full face, left and right oblique; full face, left and right profile; full face, left and right rear oblique; full face, rear, left and right ear, frontal; left and right ear, oblique; left and right ear, profile; left and right ear, rear oblique; left and right ear, rear.

A1.1.4

Facelift

Full face and neck, frontal; full face and neck, left and right oblique; full face and neck, left and right profile; left and right ear, profile; left and right ear, profile, auricle retracted forward; neck, profile, maximum flexion and extension.

A1.1.5

Platysmaplasty, submentoplasty

Neck, frontal; neck, left and right oblique; neck, left and right profile; neck, frontal, platysma contracted; neck, left and right oblique, platysma contracted; neck, left and right profile, platysma contracted; neck, frontal, maximum flexion and extension; neck, profile, maximum flexion and extension; left and right ear, profile; left and right ear, profile, auricle retracted forward.

A1.1.6

Blepharoplasty and/or Brow Lift

Full face, frontal; full face, left and right oblique; full face, left and right profile; upper face, frontal; upper face, left and right oblique; upper face, left and right profile; upper face, brow elevated; upper face, brow depressed; upper face, eyes gently closed; upper face, eyes tightly closed; upper face, looking up; upper face, looking down.

A1.1.7

Face and Neck Botox

Full face, frontal; full face, left and right oblique; full face, left and right profile; full face, brow elevated; full face, eyes tightly closed; full face, smiling; full face, lips pursed; full face, frowning; upper face, left and right oblique; upper face, left and right oblique, eyes tightly closed; neck, frontal; neck, left and right oblique; neck, left and right profile; neck, frontal, platysma contracted; neck, left and right oblique, platysma contracted; neck, left and right profile, platysma contracted.

Appendix: Suggested Photographic Series for Selected Situations

133 A1.1.8

Facial Lacerations

Full face, frontal; full face, left and right oblique; full face, left and right profile; full face, brow elevated; full face, eyes tightly closed; full face, smiling; full face, lips pursed; full face, frowning; macrophotographic view of laceration.

A1.1.9

Orbital and Sinus Fractures

Full face, frontal; full face, left and right oblique; full face, left and right profile; upper face, frontal; upper face, left and right oblique; upper face, left and right profile; upper face, brow elevated; upper face, brow depressed; upper face, eyes gently closed; upper face, eyes tightly closed; upper face, looking up; upper face, looking down; upper face, looking left; upper face, looking right.

A1.1.10

Fractures of Mandible and/or Maxilla

Full face, frontal; full face, left and right oblique; full face, left and right profile; lower face, frontal; lower face, left and right oblique; lower face, left and right profile; lower face, maximum mouth opening, frontal; lower face, maximum mouth opening, left and right oblique; lower face, maximum mouth opening, left and right profile; anterior dentition, lips retracted, frontal; anterior and lateral dentition, lips retracted, left and right oblique; anterior and lateral dentition, lips retracted, left and right profile.

A1.1.11

Neck Dissection and/or Thyroid Surgery

Neck, frontal; neck, left and right oblique; neck, left and right profile; neck, frontal, maximum flexion and extension; neck, frontal, left and right rotation; neck, frontal, left and right tilt: neck, frontal, shoulder shrug; neck, frontal, shoulder depression.

A1.1.12

Facial Nerve Weakness

Full face, frontal; full face, left and right oblique; full face, left and right profile; full face, brow elevated; full face, eyes tightly closed; full face, smiling; full face, lips pursed; full face, frowning, full face, cheeks puffed.

A1.1.13

Oral Cavity Lesions

Macrophotographic view of lesion, anterior dentition, lips retracted, frontal; anterior and lateral dentition, lips retracted, left and right oblique; anterior

Appendix: Suggested Photographic Series for Selected Situations

134 and lateral dentition, lips retracted, left and right profile; left and right buccal mucosa; anterior floor of mouth; oral tongue, frontal; oral tongue, left and right oblique; oral tongue, frontal, protruded; oral tongue, left and right deviated; oral tongue, elevated; left and right retromolar trigone; anterior palate.

A1.1.14

Diseases of Tonsils and Oropharynx

Soft palate and posterior pharynx; soft palate and posterior pharynx, palate elevated; left and right tonsil/tonsillar fossa.