Specimen Photography

An accurate macroscopic description of a gross specimen is often vital in making the correct diagnosis (e.g., the pattern of involvement in inflammatory bowel disease) and in accurately staging a malignant tumour. With the decline of the autopsy and the controversy surrounding organ retention, macroscopic specimen photographs also play an important role in undergraduate teaching, and may be correlated with radiological images in today's integrated courses. Macroscopic specimen photography has also been used to audit the quality of mesorectal excision in rectal cancers and it is an important communication medium in multidisciplinarian team meetings. Another factor that may contribute to its increasing use includes participation of BMSs in specimen dissection and in the selection of tissue for histology; specimen dissection is inherently destructive and sequential pictures can be used to record key features of the specimen.

The principles of specimen photography are described in many standard textbooks of surgical pathology and some reviews. It is important that there is a clean, textureless background that is suitably illuminated. Reflective glare and wet highlights should be avoided by switching off the room lights, correctly positioning the illumination system and blotting the cut surface of the specimen. The specimen should be properly centred and orientated. In general, the cut surface usually provides more information than the external aspect of a specimen. It is important to trim away fat and other extraneous tissue and to slice the tissue cleanly. It may be advantageous to open ducts, etc. to highlight these structures but the inclusion of probes and forceps or other objects can be distracting.

The use of a stand is recommended. A 35 mm camera may be used. A smaller lens aperture (higher f-stop) will maximise the depth of field for specimens of a substantial height and many photographers will use a number of slightly different exposures. Polaroid cameras offer a convenient method to produce specimen pictures rapidly that can then be marked as to the origin of blocks for histology. However, such pictures are often of poor quality and it is not easy to produce 35 mm slides from the prints. Digital photography can be used to produce high-quality images relatively cheaply and hard copy rapidly. Digital images may be archived easily on CD ROM and software systems exist that allow the incorporation of digital images into biopsy files. Non-specialised equipment can give good results and the use of a simple scanner has recently been advocated.

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