Nerve Sparing Is Beneficial for Recovery From Urinary Incontinence in Patients With Shorter Membranous Urethral Length After Robot‐Assisted Laparoscopic Radical Prostatectomy

PURPOSE: We analyze determinants of postoperative recovery from urinary incontinence following robot-assisted laparoscopic radical prostatectomy, with a focus on membranous urethral length and inclusion of nerve sparing. MATERIALS AND METHODS: This retrospective study included patients who underwent robot-assisted laparoscopic radical prostatectomy from 2017 to 2022 performed at a single institution. Cox proportional hazards analysis was conducted for postoperative recovery from urinary incontinence, defined as use of zero or one pad/day. Examined patient factors were age, body mass index, prostate volume, and membranous urethral length, while surgical factors were nerve-sparing status, operative time, and console time. RESULTS: A total of 197 patients were included in the analysis. Median membranous urethral length was 11.6 mm. Nerve sparing was performed in 92 (46.7%), with unilateral preservation in 68 and bilateral preservation in 24. In total, patients both univariate and multivariate Cox hazard analyses showed that the only significant factor for recovery from urinary incontinence was membranous urethral length (hazard ratio 1.059, p = 0.01), while nerve sparing was not significant (hazard ratio 1.132, p = 0.43). However, when patients were subdivided into two groups based on the median value for membranous urethral length (11.6 mm), nerve sparing was not a significant factor for recovery in the longer group (≥ 11.6 mm, n = 99, hazard ratio 0.898, p = 0.64), while that was significant in the shorter group (< 11.6 mm, n = 98, hazard ratio 1.55, p = 0.049). CONCLUSION: The present results may indicate that nerve sparing is more recommended for patients with a shorter membranous urethral length.