The hemodynamics of erectile dysfunction following nerve-sparing radical retropubic prostatectomy.

Overview

OBJECTIVE: Despite the advent of the nerve-sparing radical retropubic prostatectomy (NSRRP) a significant number of men still suffer from post radical prostatectomy impotence. The purpose of this study was to investigate the pathogenesis of erectile dysfunction following NSRRP and to define the previously reported vascular mechanism. Furthermore, it was our goal to clarify the respective contributions of arterial and venous components. PATIENTS AND METHODS: Sixteen potent males with localized prostate carcinoma underwent dynamic infusion cavernosometry preoperatively to assess arterial and venous hemodynamics. Ten of these men were impotent following the operation and had repeat cavernosometric evaluation six months postoperatively. RESULTS: On cavernosometry all 10 patients had arterial insufficiency on at least one side, six patients had bilateral changes. The mean reduction in CAOP was 50% (range 30-70%). Four patients met criteria for the diagnosis of corporovenocclusive dysfunction on cavernosometry. CONCLUSIONS: These data strongly support a vascular mechanism in the genesis of post-NSRRP impotence. This mechanism is predominantly arterial in nature, but some men have a mixed pattern with both arterial and venous components. The postoperative arterial insufficiency may be the result of intraoperative injury to the accessory pudendal artery. The exact means by which CVOD develops in this situation remains unclear at this time.