Association of Surgeon Subjective Characterization of Nerve Sparing Quality With Potency Following Laparoscopic Radical Prostatectomy

Abstract

We assessed whether a surgeon self-graded assessment of neurovascular bundle preservation quality predicted potency following laparoscopic radical prostatectomy. From April 2001 to January 2007 a total of 767 laparoscopic radical prostatectomies were performed by 2 surgeons who graded left and right neurovascular bundle sparing qualities on a scale of 0 to 5. The total number of nerves spared was also recorded. We defined a composite variable, the bilateral sum neurovascular bundle sparing score, to encode 1 independent variable (scale of 0 to 10) for analysis. Multivariate linear regression models were evaluated to assess the significance of the bilateral sum neurovascular bundle sparing score for predicting validated potency outcomes, controlling for significant clinical variables in preoperatively potent men (Sexual Health Inventory for Men 21 or greater). The bilateral sum neurovascular bundle sparing score based model was compared to a model based on the separate number of nerves spared. A total of 313 patients were preoperatively potent, of whom 226 (72%), 77 (25%) and 10 (3%) underwent bilateral, unilateral and no neurovascular bundle sparing, respectively. Of the men who underwent bilateral neurovascular bundle sparing 64.3% were engaging in intercourse by 1 year. Regression models indicated that the bilateral sum neurovascular bundle sparing score and the number of nerves spared were highly significant independent positive predictors of postoperative sexual function (p <0.001). The bilateral sum neurovascular bundle sparing score model provided differential prognostic information in the majority group that underwent bilateral nerve preservation. Other independently predictive variables were patient age at surgery, months since surgery and preoperative Sexual Health Inventory for Men 21 to 25 (each p <0.001). Cavernous nerve preservation during laparoscopic radical prostatectomy is not an all or none phenomenon. A surgeon subjective sense of neurovascular bundle sparing quality may aid in accurately characterizing the return of sexual function following laparoscopic radical prostatectomy. Partial nerve preservation may lead to an incremental improvement in the return of sexual function.