Quantitative and qualitative analysis of the recovery of potency after radical prostatectomy: effect of unilateral vs bilateral nerve sparing

Abstract

To analyse the impact of a approximately 50% reduction of cavernous nervous tissue on the qualitative and quantitative recovery of sexual function after unilateral (UNS) and bilateral (BNS) nerve-sparing robotic radical prostatectomy (RALP), by evaluating these differences in two groups treated with cautery and a cautery-free technique (CFT). UNS was defined as wide-excision of one neurovascular bundle (NVB). Only men aged < or =65 years with preoperative International Index of Erectile Function (IIEF-5) scores of > or =22 were included. The cautery group comprised 42 men (of case numbers 1-125) undergoing RALP with cautery, and the CFT group (62 men of cases 151-350) had a cautery-free technique along the NVB. Data were collected prospectively using validated self-administered questionnaires. Potency was defined as two affirmative answers to: do you have erections 'adequate for vaginal penetration?' and 'Are they satisfactory?'. Patient-reported IIEF-5 scores and quality of erections (i.e. an estimate of erection as 0%, 25%, 50%, 75% or 100% of preoperative fullness) were obtained after surgery. In the cautery group, doubling the nerve volume increased potency by 1.36 times (UNS 50% vs BNS 68%). The results were similar in the CFT group as doubling nerve tissue increased potency by 1.15 times (UNS 80% and BNS 93%). At 24 months, comparing IIEF-5 scores, there was no difference between UNS and BNS for the cautery group, at 19.6 (95% confidence interval 15.7-23.5) vs 18.9 (16.6-21.0), or the CFT group, at 22.0 (20.2-23.8) vs 21.0 (19.8-22.1). Doubling the nerve volume only increased potency by 1.15-1.36 times for both the CFT and cautery groups. Furthermore, the quality of erections and IIEF-5 scores did not vary appreciably with doubling of nerve tissue.