Excretory urography, urethrography and helical computed tomography in 24 dogs with suspected ureteral ectopia

Ureteral ectopia is a congenital disorder in dogs whereby the ureters (the pipe-lines between the kidneys to the urinary bladder) do no terminate appropriately within the urinary bladder. Instead, they may terminate elsewhere in the urinary bladder or within the urethra, vagina, or vestibule. The purpose of this study was to determine the diagnostic utility of helical computed tomography (CT) for the diagnosis of ectopic ureters in the dog and to compare these findings with more conventional means of diagnosis: excretory urography and urethrography. Historically, a positive and anatomically accurate diagnosis of ureteral ectopia was made in 62 to 77% of confirmed cases using these methods. In this study, CT was determined to be more useful than other established diagnostic imaging techniques for diagnosing ureteral ectopia in the dog.

Image A is a transverse image made through the caudal urinary bladder (UB) showing excretion of iodinated contrast medium (vertical, white lines) from the normally positioned ureters. The colon (Co) is dorsal to the urinary bladder and contains some gas and fecal material. Image B is a transverse image made caudal to the urinary bladder at the level of the proximal urethra. Note that the left ureter is adjacent to the urethra. This ureter never entered the urinary bladder. Instead, it enters the urethra just caudal to where this image was made. Image B is an example of unilateral, left-sided, ureteral ectopia.
A B
Transverse image made through the caudal urinary bladder Unilateral, left-sided, ureteral ectopia
Bilateral Urethra
Bilateral urethra