Pudendal versus limb nerve electrophysiological abnormalities in diabetics with erectile dysfunction

It is of some interest to diagnose polyneuropathy and/or sacral neuropathy in diabetic males with erectile dysfunction. Non-invasive electrophysiological measurements with surface electrodes, which are widely available, have been applied to determine the diagnostic yield of several electrophysiologic parameters for assessing polyneuropathy including the pudendal nerve in impotent diabetics. Latencies of the bulbocavernosus reflex and the pudendal somatosensory evoked potentials were measured in a group of 28 diabetic patients with an erectile dysfunction as their main complaint, as well as in a group of 20 potent males without systemic disease. In diabetic patients motor conduction measurements of one median and peroneal nerve and sensory conduction measurements of one median and sural nerve were also performed. In 15 patients abnormalities of the peripheral nerve conduction were demonstrated whereas abnormalities of the bulbocavernosus reflex and/or cortical somatosensory evoked potentials were demonstrated in eight. Five patients had both types of abnormalities. In the patient group no differences could be demonstrated between those with Type 1 or Type 2 diabetes. The only significant clinical/neurophysiological correlation was found between the absence of the bulbocavernosus reflex on clinical examination and its prolonged latencies on electrophysiological measurement. The study showed that a bigger yield of abnormal results was obtained when pudendal nerve function parameters were included in the evaluation of diabetics with erectile dysfunction. Considered separately, however, the battery of electrophysiological tests evaluating limb nerve function seems more sensitive in diagnosing neuropathy than electrophysiological assessment of pudendal nerve function alone.