Cavernous nerve stimulation through an extrapelvic subpubic approach: role in penile erection

The results of cavernous nerve (CN) stimulation through an extrapelvic subpubic approach in 12 dogs are presented. The nerve was exposed and identified by a magnifying loupe and electric stimulation. A bioplar platinum electrode was then applied to the nerve and a radiofrequency receiver implanted subcutaneously into the abdomen. The CN was stimulated (pulse width 200 microseconds, range density 2-6 microCi/cm2/phase) and the intracavernous pressure was recorded. CN stimulation led to intracavernous pressure increase. With increasing stimulus frequency, the pressure increased while the latency and stimulation phase decreased, until at 60 Hz frequency no further changes occurred. Increasing CN stimulation was accompanied by a progressive increase in penile length and diameter leading to full erection at a frequency of 60 Hz. The penile response was more rapid and of a shorter duration with stronger stimulation. CN stimulation could be repeated indefinitely without fatigue after an off-time of double the period of the stimulation phase. The extrapelvic subpubic approach to CN is simple and without complications, and can be applied safely in humans.