Intraoperative electrophysiological confirmation of urinary continence after radical prostatectomy

PURPOSE: To determine the actual effect of nerve sparing radical retropubic prostatectomy (RP) on postoperative urinary continence we used intraoperative electrophysiological testing to confirm functional preservation of the neurovascular bundle (NVB). MATERIALS AND METHODS: A total of 85 patients undergoing RP for localized prostate cancer were studied. During RP NVB preservation was assessed macroanatomically. Electrophysiological testing was then performed to confirm NVB preservation. The NVB was electrostimulated and responses were observed by monitoring intracavernous or intraurethral pressure changes. All patients were classified into 3 groups according to the degree of nerve sparing, that is a bilateral nerve sparing group, a unilateral nerve sparing group and a nonnerve sparing group, based on macroanatomical assessment as well as on electrophysiological assessment. Postoperative continence in each group was then determined. Urinary continence at baseline, and 3 and 6 months postoperatively was studied using a self-administered questionnaire. RESULTS: With electrophysiological assessment 20.6% of macroanatomically determined NVB preservations were reclassified. Analysis of the data on groups classified accurately by electrophysiological testing showed that the bilateral nerve sparing group maintained postoperative urinary function significantly more than the unilateral nerve sparing and nonnerve sparing groups. However, when only macroanatomical assessment was considered, no significant difference among the groups was found in urinary function. CONCLUSIONS: Electrophysiological assessment revealed that bilateral NVB preservation contributes to early recovery of urinary continence after RP. Thus, intraoperative electrophysiological assessment is useful for predicting postoperative quality of life.