[Long-term efficacy of tubularized peritoneal free grafts as ureteral mucosal substitutes in dogs].

Objective To investigate the long-term efficacy of ureteral reconstruction with tubularized peritoneal free grafts for the treatment of avulsion of ureteral mucosa in animal models.Methods The model of avulsion of ureteral mucosa was established in 12 adult dogs.Then they were divided into Group A (n = 6,length of avulsed mucosa at 4 cm) and Group B ( n = 6,length of avulsed mucosa at 6 cm).And the tubularized peritoneal free grafts and ureteral stents were implanted into the injured ureters.The curative effect was observed by intravenous urethrogram (IVU) and histological examination at Week 24 post-operation.Results Severe stenosis was observed by IVU in 1 dogs in Groups A and B respectively.In the remaining 10 dogs,IVU showed normal size and morphology of kidneys.There was no hydronephrosis.And no obvious stricture of ureteral part was observed for mucosa substitutes made of peritoneal free grafts.In all 10 dogs without stenosis of both groups,peritoneal membrane was replaced by integrated transitional epithelium.And there was no obvious stricture.Collagen fibers were arranged parallel to mucosal surface.Conclusion For avulsion of ureteral mucosa under 6 cm,reconstruction with tubularized peritoneal free grafts as mucosa substitutes is an effective method.And its long-term efficacy is satisfactory. Key words: Ureteral diseases;  Peritoneum;  Mucous membrance;  Avulsion