Maximum-distention retrograde urethrocystography in healthy male dogs: occurrence of vesicoureteral reflux.

Twenty-four healthy, mature male Beagles were examined radiographically for vesicoureteral reflux (VUR) by maximum-distention retrograde urethrocystography. Bilateral VUR was observed in 9 dogs and unilateral VUR was observed in 3 dogs. The VUR occurred when the bladder was full or nearly full when maximum bladder filling was defined by trigonal-prostatic urethral dilation. The refluxed contrast medium reached the renal pelves in all but 3 of the 21 affected ureters.