Small Animal Radiology and Ultrasound: A Diagnostic Atlas and Text

420 Small Animal Radiolo g y and Ultrasono graphy
Fig. 3-220 A to D, Longitudinal
sonograms of the urinary bladder of
a 4-year-old spayed female English
Cocker Spaniel with a history of
lumbosacral pain. There is echogenic
material in the dependent portion of
the urinary bladder. In scans A and
D the material is predominantly layered
on the dorsal (dependent) surface
(arrows). In scans B, C, and D
the bladder has been agitated and the
material is evident floating within
the urine. Diagnosis: Sand, or fine
calculi, within the urinary bladder.
A
B
C
D
Fig. 3-221 Longitudinal (A and B)
and transverse (C and D) sonograms
of the urinary bladder of a 14-yearold
spayed female mixed breed dog
with a history of polyuria and polydipsia.
There is a hyperechoic region
within the urinary bladder with a
reverberation artifact indicating the
presence of air. This region was consistent
in position despite changes in
the dog’s position. It is indicative of
air within the bladder wall.
Diagnosis: Emphysematous cystitis.
A
B
C
D
(Fig. 3-223). 457 The colliculus seminalis may be noticeable as a dorsal filling defect in the
prostatic urethra (Fig. 3-224). 466 In some normal male dogs, the prostatic urethra may
appear narrow but the borders will be smooth and regular. This is considered to be a function
of the intraurethral versus the extraurethral pressure.
Density and Shape Changes. Radiolucent urethral calculi may be seen on the urethrogram
(Fig. 3-225). These will appear as irregularly shaped radiolucencies, usually small ones, within
the column of contrast media. 717 It is important that proper urethrographic technique is followed
so that air bubbles are not introduced during contrast injection and mistaken for cal-