Covering of the terminal ureter with de-serosalized muscle layer of the ileum for antireflux ureteroileostomy: an experimental study in dogs and a preliminary clinical trial.

We demonstrated a new operative technique for antireflux ureteroileostomy in dogs. The severed ureter was reimplanted into the isolated ileum. Ten terminal ureters were covered with a 2 x 2 cm2 section of de-serosalized ileal wall after direct ureteroileostomy, and another six terminal ureters were covered with a 2 x 2 cm2 section of non-de-serosalized full-thickness ileal wall. Thirteen ureters were directly anastomosed to the ileum without any additional procedures. The bladder was augmented by the detubularized ileum with the ureter. Postoperative evaluations on ureteral stenosis and reflux were performed monthly for 3 months. The ureters covered with the de-serosalized ileal wall prevented ureteral reflux even when the intravesical pressure climbed as high as 100 cm H2O. Although two of these ten ureters demonstrated strictures at the precise site of direct ureteroileostomy, the sections of the ureters covered with the de-serosalized ileal wall were opened and did not collapse. In the resected specimens, the terminal ureters were found in the intramural part of the ileum. The ureters covered with the full-thickness of ileal wall did not prevent reflux. Our method of covering the terminal ureter with the de-serosalized ileal wall worked well as an antireflux mechanism, and the intramural ureter did not cause ureteral stricture. After this animal experiment, we introduced this antireflux mechanism clinically.