Evaluation of Conduction Properties of Somatic and Sympathetic Sudomotor Fibers in Patients With Epilepsy

Abstract

To assess the function of fast somatic nerve fibers and sympathetic sudomotor system in patients with partial or generalized seizures, receiving various therapeutic regimes. The authors studied 60 patients (mean age 36.7 +/- 12.5 years) and 60 matched healthy controls by clinical, conventional nerve conduction study, and sympathetic skin responses (SSR) from hand and foot. Compared with controls, patients showed a tendency, occasional reaching significant level, to conduction slowing and amplitude reduction in the sensory and less often in the motor nerve study. Clinical signs of neuropathy were disclosed in 8.3% of patients, whereas at least one abnormal sensory parameter was evident in 18.3%. Mean SSR latencies in the patients were significantly prolonged. At least one SSR abnormality was shown in 20 (33.3%) patients; six of these had absent SSR from the hand or/and the foot. Polytherapy (vs. monotherapy) and topiramate, but not any other particular drug, seemed to have a negative effect on SSR measurements. The results suggested that despite the insignificant clinical manifestations of neuropathy, an electrophysiological examination was able to demonstrate some subclinical abnormalities of the fast somatic fibers in the peripheral nerves and of the sympathetic sudomotor function in a considerable number of epileptic patients.