Segmental replacement of the ureter using tapered and nontapered ileum.

We attempted to reduce the absorptive surface area and maintain the natural antireflux mechanism of the distal ureter by using ileum as an interposed segment rather than a total ureteral substitute in six dogs. In each dog we compared the physiologic effects of a longitudinally tapered ileal segment versus a simple nontapered segment. Information from the intravenous pyelogram, renal function tests, and the pressure flow studies showed preservation of renal function and parenchyma, no secondary dilation of the upper tracts, continued peristaltic activity, no evidence of obstruction or stone formation secondary to mucus production, no early pyelographic abnormalities, and no differences in pressure flow characteristics between the tapered and nontapered segments. We believe that incorporating ileum into the urinary tract to bridge a ureteral defect is a safe and effective clinical alternative.