Penile neuropathy in insulin-dependent diabetes mellitus.

The dorsal nerve of the penis has been linked closely to penile erection and response. We measured the nerve conduction velocity of the dorsal nerve of the penis, latency of the bulbocavernosus reflex and pudendal evoked potential in 23 normal men and 20 insulin-dependent diabetics with impotence. The conduction velocity of the dorsal nerve of the penis was significantly slower in diabetic than in normal men and passive gentle elongation of the penis by weight stretching enhanced the slowing. In contrast, the bulbocavernosus reflex and pudendal evoked potential showed no significant differences between the 2 groups. We demonstrate the potential usefulness of measurement of the conduction velocity of the dorsal nerve of the penis in the detection of penile neuropathy.