The Influence on the Upper Urinary Tract by Dilatation to Vesicoureteral Junction in Rabbit

Kim, Hyun Soo; Yoon, Jong Byung

Abstract

After transverse incision of bladder of 21 rabbits weighing from 1.6 kg to 2.0 kg, each left ureteral orifice was dilated from l Fr up to 4 Fr progressively, and the rabbits were sacrificed at 3rd. 7th and 28th day after dilatation of ureteral orifice. We studied the changes of upper urinary tract due to the dilatation of vesicoureteral junction with imaging diagnostic methods, such as retrograde cystography, intravenous pyelography, and histopathologic examination. 1. Vesicoureteral reflux after dilatation of ureteral orifice did not occur in 4 Fr group, but occur- red in 2 rabbits(20 %) of 5 Fr group. Hydronephrosis and dilatation of ureteral lumen were observed at the 3rd and 7th day after the dilatation of ureteral orifice, whereas on the 28th day did were not observed. 2. The histopathologic findings of ureteral damage were denudation of ureteral orifice. Major causes of ureteral damage were denudation of ureteral mucosa and tearing of ureter, involving submucosal layer. Nonspecific inflammatory reaction was ensued following these damage. It is suggested that the range of ureteral dilatation, which will have minimal influence on urinary tract with safety, in rabbits weighing from 1.6 kg to 2.0 kg, is less than 4 Fr.