Erectile impotence in multiple sclerosis: a neurophysiological study.

Pudendal evoked potentials, motor evoked potentials of the bulbocavernosus muscle to magnetic stimulation and bulbocavernosus reflex were recorded in 34 patients with multiple sclerosis (MS). Responses were delayed in 26, 20 and 3 cases respectively. No relationship was found between neurophysiological abnormalities and the presence or severity of erectile dysfunction, showing that these tests have little diagnostic usefulness in MS patients with impotence. Nocturnal penile tumescence was assessed in 14 cases: the test result was normal in 10 patients, including 3 severely paraplegic subjects.