Page 69 - Veterinary diagnostic imaging birds exotic pets wildlife

Chapter 6

The Wing: Radiography and Normal

Radiographic Anatomy

III RADIOGRAPHY OF THE WING jections designed to either reduce or eliminate super-
imposition or to show a different profi le.
Many of the following points on avian radiography
were made previously in Chapter 1 but warrant reem-
phasis because of their importance. III RESTRAINT
Unlike most forms of radiography, avian radiogra-
phy often requires less radiation to produce a quality Gas anesthesia is the ideal way to restrain wild birds
image. The most common faults encountered in wing during radiography and was used in nearly all of the
radiography are excessive darkness and diminished cases illustrated in this book. Gas anesthesia has the
contrast stemming from overpenetration. Great care advantages of being easily administered, readily regu-
should be taken to position the bird symmetrically for lated, and quickly eliminated from the system once the
the ventrodorsal (VD) projection because it provides examination has been completed.
an excellent comparison view of the opposite (hope-
fully normal) wing. This opposite view can substan-
tially assist diagnosis of a fracture in a multiple bone III POSITIONING
joint such as the shoulder.
We customarily tape the wing of a large bird, such as
a bald eagle or great blue heron, to a 14- by 17-inch
III THE STANDARD EXAMINATION cassette, flexing or extending it to fully fit on the

receiver. In the case of a lateral projection, during
Ideally, a standard wing examination is comprised of which the bird is positioned manually, two or even

two projections: a VD and a lateral (my preferred three films may be necessary because of the need to
term), which is also termed the leading edge or hanging fully extend the wing, maximizing its length, but
drop projection. When it comes to articular fractions making adjustment impossible.
and subtle dislocations, especially of the humeral
or cubital joint, the lateral view frequently proves
indispensable. III PRECAUTIONS
Some precautions to consider when handling raptors
III SUPPLEMENTARY EXAMINATIONS before radiography are to wear protective eyewear and
long protective leather gloves that cover as much of
A supplementary view is usually made to visualize a the lower arm as possible. For water birds with long
bone or joint more clearly or from a different perspec- beaks, a full-face shield is desirable.
tive. The most common supplementary view used in It is best to cover the bird’s head with a soft towel
our practice is made of the shoulder, followed by the while it is conscious, work in dim light, and avoid loud
elbow. In most instances, these views are oblique pro- or abrupt noises. All of the necessary equipment should
65

2/11/2008 11:43:20 AM
ch006-A02527.indd 65
ch006-A02527.indd 65 2/11/2008 11:43:20 AM