ULTRASONOGRAPHIC APPEARANCE OF URETHRAL TRANSITIONAL-CELL CARCINOMA IN 10 DOGS

The mucosal margin of the urethra is best assessed by positive contras t urethrography, but ultrasonography offers complementary information such as urethral wall thickness and size of medial iliac lymph nodes. Ultrasonography of the urethra is quick, noninvasive and does not requ ire sedation or general anesthesia, In patients with complete urethral obstruction, ultrasonography may be the only way to image the urethra , Twelve dogs which were presented to Tufts University School of Veter inary Medicine with clinical signs referable to the urinary bladder, u rethra or vagina were examined ultrasonographically, Seven were neuter ed females and five were neutered males, Each dog had a hyperechoic, n onshadowing line at the epithelial surface of the proximal urethra, In the seven female patients and one of the males, the urethral wall was also thick and hypoechoic to surrounding tissue, In the other males, the urethral epithelial changes were at the level of the prostate, and the limits of the urethra were not visible, In six dogs, the urethral change was the only abnormality seen, while in six, bladder wall, bla dder luminal and/or prostatic parenchymal changes were also detected, Three patients had hydronephrosis, and one had enlarged medial iliac l ymph nodes, Biopsies were obtained via suction with urinary catheteriz ation (n = 6), exploratory celiotomy (n = 3), urethroscopy (n = 2), or at post-mortem (n = 1), A histopathologic diagnosis of urethral trans itional cell carcinoma was obtained in ten dogs, The ultrasonographic appearance was not pathognomonic for transitional cell carcinoma, as o ne dog with transitional cell dysplasia and one dog with severe ulcera tive and necrosupperative cystitis and urethral stricture had similar findings.