The ability to make accurate, permanent, and objective images of medical conditions, outcomes, and observations has been vital to the progress of medical science for over 150 years. Medical photography is a highly specialized profession, demanding much more than technical skills from its practitioners, which is why it is also known as biomedical photography. In this extensive discipline the images are made to document all of the prominent features of a subject without exaggeration, enhancement, distortion, deliberate obliteration, or the addition of details that might lead to misinterpretation by the viewer. These subjects may include clinical photographs, surgical procedures, surgical specimens, autopsy and forensic material, tissue slides, bacterial specimens, laboratory preparations, graphic and fine art renditions, medical equipment, and public relations features, as well as illustrations for publications and presentations. Of course, not all biomedical photographers will be masters of all these techniques, but any competent practitioner will be familiar with most of them. Medical diagnostic imaging (MRI, CT scanning, and other specialized techniques) and medical radiography are considered elsewhere in this encyclopedia.
A Brief History of Medical Photography
Illustration has been an important feature of medical documentation since the time of Vesalius and thus has a long history. However, the first application of photography to medicine appears in 1840, when Alfred Donné of Paris photographed sections of bones, teeth, and red blood cells using an instrument called the microscope-daguerreotype. Conventional medical photography apparently began in France when J. G. F. Baillarger photographed cretins (1851), which was followed by a Dr. Behrendt of Berlin photographing his orthopedic cases in 1852, and in the same year by Dr. Hugh Welch Diamond photographing mental patients at the Surrey County Asylum in England.
During the American Civil War (1861–1865), countless photographs were made of wounds; these photographs are preserved at the National Library of Medicine, Washington, D.C. In 1861 Jacob Gantz made stereoscopic photographs for T. Billroth at the Chirurgical Clinic in Zurich. J. N. Germack made photographs through the endoscope (1862), and the human retina was photographed by William Thomas Jackman and J. D. Webster in 1885.
A new era in medical photography occurred when E. J. Muybridge synthesized motion studies (chronophotog-raphy) of humans and animals (1877–1893), which greatly stimulated other investigators in medical photography, and the French physician Étienne-Jules Marey endeavored to analyze human and animal motion by serial photographic studies (1882) and devised a chronophotographic apparatus and projector (1890), which was the forerunner of the modern motion-picture camera. By the turn of the century, applications were too numerous to mention, but in 1927 R. P. Loveland made a medical teaching film using cinephot-omicrography, demonstrating the life history of the yellow fever mosquito, and in 1929 F. Neumann in Germany made a time-lapse film of living bacteria.
The first medical publications illustrated with photographs were Album de Photographies Pathologiques and Mecanisme de la Physiologie Humaine (1862) by G. B. Duchenne, the founder of electrotherapy. The Photographic Review of Medicine and Surgery (1870), by F. F. Muary and L.A. Duhring, was the first medical journal illustrated with photographs. Albert Londe in 1888 published a book, La Photographie Moderne , containing information on medical photography and also the first book specifically devoted to medical photography, La Photographie Medicale in 1893.
The Medical Photographer
From the photographic perspective, the medical photographer is obliged to be versatile and innovative, possessing a broad knowledge of the photographic process and ancillary activities such as digital image editing. One of the prime requisites of a medical image is that it be permanent, properly classified, recorded, and filed for easy retrieval. The photographer is thus expected to have a good knowledge of computers for storage, indexing, retrieval, and distribution of images. Images may be recorded on conventional silver halide based films, on video tape, on digital imaging media, or other contemporary recording material, so the capabilities of these media is also important. The medical imager is thus responsible for managing a large inventory of images that is constantly being augmented. When these are tied to patient records an extremely valuable resource is created.
A medical photographer may be called upon to use a variety of specialized techniques, such as infrared and ultraviolet reflected or fluorescence imaging, endoscopy and fiberoscopy, polarized light, intra-oral photography, stereo imaging and photogrammetry, contour mapping, and photo-macrography and photomicrography. An area that has been traditionally a big part of the work in medical photography has been reprographics, photographing texts, charts, and graphs; and radiographs for lectures, posters, presentations, and publication. With the evolution of digital imaging methods, this activity has changed dramatically, so layout and desktop publishing is now often done in-house and by the medical photographer. Medical photographers also sometimes manage audiovisual services for medical conferences, so they must understand the basic principles of audiovisual presentations such as the characteristics of microphones, sound amplification, audio recording, projector equipment, and screen requirements.
Apart from the obligatory photographic, multimedia, and administrative skills, the medical photographer must have a good general knowledge of anatomy and an elementary knowledge of physiology and histology and be familiar with the common everyday terms used in pathology, bacteriology, radiology, and surgical procedures. In addition, the photographer should possess a reasonable knowledge of medical prefixes, suffixes, and abbreviations frequently used in medicine, and be familiar with all hospital protocol, particularly regarding obtaining informed-consent patient releases for all visual or audio recording and reproduction purposes.
The photographer also needs to have an understanding of, and sensitivity to, a patient’s condition and state of mind and be able to provide for the patient’s safety and dignity during the photographic procedure. Tact and patience has to be exercised to make the patient comfortable, even under stressful circumstances. Work in theatres, wards, and post-mortem rooms can also be very stressful for the photographer. At the same time the photographer needs to be aware of the infectious nature of certain diseases and take precautions to avoid contact and to protect fellow employees from hazardous circumstances.
Medical Photography in Practice
The range of equipment employed in medical photography will vary with the application and the institution. The standard setup includes the popular 35 mm single lens reflex (SLR) film camera with a comprehensive range of lenses, lighting equipment, and accessories or digital equivalents. The digital cameras may be of the same make as the film cameras to ensure the ability to share all the various accessories, especially lenses. The availability of compact digital equipment means that the photographer can often go to the patient ward, especially in large institutions, though a well-equipped studio is usually an essential. Other equipment, depending on the application, may include large format cameras, video cameras, photomicrography setups including time-lapse configurations, photomacrography setups including flatbed scanners, endo-scopic and ophthalmic cameras, and a host of other specialized equipment designed for specific imaging techniques. Many departments will have a suite of computers for editing, storing, and filing images, often connected to the institutional network for rapid transmission of results.
A wide range of films are available; some brands are preferred by medical photographers for their good color reproduction and resolution, while digital cameras can be balanced for flash lightning. Whatever is used, it is important to be able to precisely reproduce lighting conditions. The first picture that is taken should give a neutral rendition of the patient or area. Two studio flashes set at 45 degrees will create even illumination for the most accurate color reproduction. The light is then adjusted to reveal cutaneous structures, such as a swollen tissue or the color of a disease as required. A general view of the area is photographed and then a close-up of the detail is also taken. Where completely shadow-less lighting is required at close distance, and for photographing cavities, a circular flash tube (ring flash) around the camera lens is used.
Photography in the operating room (theater) is among the most challenging tasks for the medical photographer. It requires careful attention to the emotional and physical environment in the room, especially sterile protocol, and, of course the photographer must remain unruffled during any emergency. The photographer will often confer with the surgical team in the placement of the camera, lights, and recording equipment. Before entering the theater, the photographer must discuss with the surgeon the procedure, from what position and angle to photograph the operative field, and the anticipated end-use of the material. Where possible, during the photography swabs and dirty drapes should be removed and replaced so that nothing distracts from the area of interest.
In the studio, a neutral background that does not introduce a color cast that could change the appearance of the skin is desirable. If a black background is used, care has to be taken to light the subject so that the profile and hair of the patient are not lost in the photograph. Other background colors preferred are white, gray, and blue. A plain white sheet can serve as a background when photographing on the ward. When photographing in the theater it is advisable to change the drapings if soiled before taking the photograph. It is also important to
remove objects and makeup that will disturb the view that is to be photographed unless it causes the condition.
Medical photographs can share a great deal about a patient’s condition and serial photographs taken over a period of time may reveal much about the progress of disease or response to treatment. This makes the medical image a valuable asset for the patients medical record as well as in teaching, patient information, PR, and medico-legal work. For this to be effective it is important that the only variable should be in the patient and everything else should stay the same—viewpoint, positioning, lighting, color, magnification, and background.
To standardize the magnification when photographing the different parts of the body, a set of standards referred to as the Westminster Scales should be used. Practical details can be found in any good medical imaging textbook. By using these settings, closely matching images can be achieved over a period of time, independent of the number of photographers involved in the work. Guidelines have been set up to ensure that certain conditions and views are documented in the same way for a variety of relatively common conditions such as cleft lip and palate, mole mapping, the nine positions of gaze, scoliosis (spinal deformity), etc.
The Westminster Scales were originally set up for 35mm film and they will have to be modified when using digital cameras as the CCD sensor usually is smaller than the film. When choosing a lens for 35mm film, a focal length of around 100mm allows distortion-free images in most clinical situations, but a shorter focal length of around 50-60 mm will be needed for full-length photographs, or when working in a confined space.
While many photographic specialties are disappearing, the modern medical photographer finds their skills, versatility, and experience in demand, and many medical imaging departments now offer a comprehensive photographic and graphic image service to their institutions.
By
STAFFAN LARSSON
Karolinska Institute
JONAS BRANE
Scientific and Technical Photography Consultant
Medical Photography – Introduction, A Brief History of, The Medical Photographer, in Practice