ABSTRACT
Ureteral replacement has always been a challenge. In this article, we tried to assess the outcome of segmental ureteral replacement using a free peritoneal tubal graft in a dog. Transperitoneal exploration of the upper urinary tract of 6 Mongrel dogs was performed and creating a free peritoneal graft. A 2cm segment of right upper ureter was excised, while the left ureter was left as a control. This segment was replaced by a peritoneal tube around a 6 F double-J ureteral stent which was removed after one month. Follow up intravenous urography [IVU] and abdominal ultrasonography were done prior to autopsy. All animals were sacrificed 3 months after the initial procedures for gross and histopathological assessment. All animals survived the entire follow up of 3 months without serious complications. Two months after stent removal, follow-up IVU and abdominal ultrasonography revealed that variable degrees of hydroureteronephrosis were noticed on the right kidney and ureter with normal left side. At the time of sacrifice, there was moderate to severe hydroureteronephrosis above the level of the periotoneal tube in all animals. Abdominal adhesions and narrowing of the ureteral lumen at the site of the graft were observed. Histopathological interpretation showed that the urothelium was creeping over the mesothelial graft with focal inflammation and fibrosis in all cases while local osseous metaplasia of the graft was noticed in three dogs. Ureteral replacement by peritoneal tube was unsatisfactory despite the usage of ureteral stent. Further studies are needed to evaluate the use of peritoneal patch graft or other biomaterials for ureteral reconstructions