Evaluation of human amniotic membrane as a substitute for transitional epithelium of bladder in dog

To evaluate the use of fresh placental membrane as a feasible, economic and acceptable organic agent for bladder reconstruction and replacement, twelve cross hybrid dogs underwent partial cystectomy and subsequent closure (two controls) or patch augmentation with a 4x4 centimeter patch of human placental membrane, sutured to the remaining bladder in a watertight fashion. The dogs were sacrificed six weeks after surgery. Grafts remained in place in all cases, except in one of the dogs in the augmentation group which developed patch perforation, urine leakage and finally peritonitis. In others, histological examinations revealed evidence of regeneration of normal-appearing urothelium, lamina propria, neovascularization, retracting placental patch, and reconstitution of a normal-appearing and functioning bladder. This showed that placental membranes, because of their low antigenic properties, easy availability and tolerability by host urinary tract, provide an excellent graft material for the urinary tract reconstructions.