[Clinical Utility of Upper Urinary Tract Reconstruction by Ileal-Ureter Substitution]

We retrospectively reviewed the indications and outcomes of ileal-ureter substitution cases for complex ureteral reconstruction. We analyzed the patient clinical characteristics, outcomes, and complications of eight patients who had ileal ureter substitution surgery at Kyoto University Hospital between 2009 and 2016. The median patient age was 55.5 years (36-79), and the median follow up period was 25.5 months (7-85). Seven patients had unilateral ureteral obstruction (right:left=4:3), and one had bilateral ureteral obstruction. The etiologies of the ureteral defects were ureteral stricture due to non-urologic malignant tumorinvasion (n=2), benign ureteral stricture (n=2), anastomotic stricture after cystectomy (n=2), and iatrogenic ureteral injury (n=2). The mean length of operation time was 384.7 minutes (median 323 minutes, 242-397), and the mean hospital stay was 32.9 days (median 31 days, 19-41). Simple anastomosis of an untailored ileal segment to ureter and bladder was performed in 5 cases, bilateral ureteral anastomosis to a single ileal segment in one case, and in the remaining two cases, the ileal ureter was anastomosed to ileal conduit or neobladder. A nipple valve was used as the antireflux mechanism, in 2 cases but not in the remaining 6 cases. The outcome was favourable in all cases with no stricture and no requirement for further intervention. There was no significant deterioration of renal function in any patient, and no metabolic abnormality was detected. The ileal-ureter substitution appears to be a reasonable option, allowing nephron sparing in complex ureteral reconstruction cases.