Anatomical predictors of long-term urinary incontinence after robot-assisted laparoscopic prostatectomy: A systematic review.

Abstract

There is scarce evidence of anatomical risk factors that might affect long-term post-prostatectomy incontinence (PPI) in patients undergoing robot-assisted laparoscopic prostatectomy (RALP). This systematic review aims to identify anatomical measurements in preoperative magnetic resonance imaging (MRI) that might be associated with increased risk of urinary incontinence (UI) 1 year after RALP. A comprehensive search on Pubmed and Scopus databases up to November 2020 was performed. Eight articles met the inclusion criteria and were finally selected. The selected studies included 1146 patients. Seven articles focused on membranous urethral length (MUL); all of them related MUL to long-term PPI in univariate analysis and five of them in multivariate analysis. Four studies presented MUL difference to measure the magnitude of the effect. Average MUL (mm) was 15.9 (SD, 2.6), 16.1 (95% confidence interval [CI]: 13.9-18.9), 12.1 (95% CI 9.7-14.9) and 14.5 in continent patients and 13.9 (SD, 2.9), 10 (95% CI: 8.7-12.1), 10.3 (95% CI: 8.7-12.4) and 9.3 in incontinent patients, with statistically significant differences in all cases. Five studies presented the odds ratio as a result; although there was substantial heterogeneity in the methods used to obtain it, there was consistency in finding an inverse association between MUL and PPI. Other measurements including prostatic-urethral angle, membranous urethral thickness, intraprostatic urethral length and intravesical prostatic protrusion have been reported in few studies, and no association with long-term PPI was found. Levator ani muscle thickness was related to long-term PPI in one article. Greater MUL on preoperative MRI is associated with lower risk of UI 1 year after RALP.