Page 17 - Veterinary diagnostic imaging birds exotic pets wildlife

CHAPTER 1 III Avian Radiography and Radiographic Diagnosis 13

Figure 1-13 • A wildlife veterinarian holds an unconscious rough-legged hawk for a photograph immediately after radiography.

they reduce or eliminate uncertainty in the case of
III STANDARD FILM PROTOCOLS unfamiliar anatomy. The value of one or more normal
comparison views cannot be overstressed, especially
Our standard radiographic protocol consists of at least for complex parts such as the humeral joint (shoulder),
two views: (1) VD, with the bird on its back, wings which comprises four bones—three primary articular
spread, facing the x-ray tube, and (2) lateral, with the elements and one secondary medial stabilizer.
bird on its side, wings upraised, torso perpendicular
to the x-ray tube. These standard positions and the
resultant radiographic projections are shown in Figures III THE PATIENT-TAILORED,
1-14 through 1-16. SIGN-DIRECTED EXAMINATION

Whenever possible, it is best to perform patient-tailored,
III SUPPLEMENTARY VIEWS sign-directed radiographic examinations in birds. Just
as with domesticated animals, diagnostic screens
Our most common supplementary view of the injured are often not informative and arguably wasteful, as
wing is the frontal projection, which we also term the strongly suggested by an extraordinarily high rate of
leading edge or hanging drop view, in which the leading unremarkable examinations. The radiographic screen
edge of the extended wing is placed over and just should become neither a substitute for a comprehen-
above the surface of the receiver (Figure 1-17). This sive physical examination nor an offering on the altar
view often proves indispensable in establishing the of the complete database.
actual position of fracture fragments.
III WHERE AND WHAT TO LOOK FOR
III COMPARATIVE NORMALS
The diagnostic process in medical imaging as employed
Normal radiographs serve two important purposes: by experienced veterinarians and experts can be
(1) they aid in the analysis of complex injury and (2) Text continued on p. 22.

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