Characterization of a Standardized Postoperative Radiographic and Functional Voiding Trial after One-Stage Bulbar Ventral Onlay Buccal Mucosal Graft Urethroplasty and the Impact on Stricture Recurrence-Free Survival

Abstract

PurposeTo characterize a standardized postoperative radiographic and functional voiding trial and determine its impact on outcomes after substitution urethroplasty. Materials and MethodsThis is an observational, monocentric study of men undergoing one-stage ventral onlay buccal mucosal graft urethroplasty for bulbar urethral stricture between 01/2009 and 12/2016. Patients were stratified by voiding trial success versus failure (radiographic: extravasation or residual narrowness; functional: postvoid residual volume >100ml) 21 days postoperatively. Endpoints were voiding trial failure and recurrence-free survival. Regression models were created to determine risk factors of voiding trial failure and to evaluate the impact of voiding trial failure on recurrence. ResultsOf 513 men, 437(85.2%) and 76(14.8%) succeeded and failed at voiding trial, respectively. Of the latter, 54(71.1%) showed evidence of extravasation, and 22(28.9%) had residual narrowness or failed functionally. In multivariable logistic regression analyses, no preoperative predictor of voiding trial failure was found (all P>0.05). At a median follow-up of 32 months, both Kaplan-Meier analyses (log-rank test: P=0.033) and multivariable Cox regression analyses (hazard ratio=1.86; P=0.037) revealed an association of voiding trial failure and stricture recurrence. When further stratifying voiding trial failure, residual narrowness or functional failure (hazard ratio=4.60; P<0.001) but not extravasation (hazard ratio=1.08; P=0.9) was a risk factor of recurrence. Limitations include the retrospective assessment of investigated endpoints. ConclusionsResidual narrowness or functional failure at an early voiding trial after buccal mucosal graft urethroplasty may predict stricture recurrence. Identification of intraoperative complexity factors predicting initial voiding trial failure might be a key to identify those individuals who recur early.