Effect of radical retropubic prostatectomy on erectile function, evaluated before and after surgery using colour Doppler ultrasonography and nocturnal penile tumescence monitoring

Objective To assess the effect of radical retropubic prostatectomy on erectile function, by evaluating objectively patients' erectile function before and after surgery. Patients and methods The study comprised 126 patients with clinically localized prostate cancer who were scheduled to undergo radical retropubic prostatectomy. After giving informed consent for the study, 123 patients underwent intracavernosal injection tests, colour Doppler ultrasonography and nocturnal penile tumescence monitoring before and after surgery. Results From the intracavernosal injection tests and nocturnal penile tumescence monitoring, 21 patients (17%) were evaluated as having normal erectile function before surgery. After radical retropubic prostatectomy, nine (43%) of these 21 potent men had preserved erectile function. In eight patients whose neurovascular bundles were preserved, five were potent after surgery. The cause of erectile function after surgery was a neurogenic disorder in seven and a related vascular disorder in five. Conclusion From objective tests of erectile function on patients scheduled to undergo radical prostatectomy, 17% had normal erectile function. However, even after nerve-sparing radical retropubic prostatectomy, the proportion retaining potency was unsatisfactory. Although a neurological disorder was the main cause of erectile dysfunction after surgery, vascular disorders were also important.