Electrodiagnosis in Facial Palsy

Abstract

Nerve excitability test, intensity-duration curve, and measurements of action potentials evoked by facial nerve stimulation (evoked electromyography) were made on 146 patients, ie, 117 with Bell's palsy, 14 with Ramsay Hunt's syndrome, and 15 with traumatic palsy. Surgical decompressions were performed on 34 patients. Long-term follow-up studies indicated that evoked electromyography was valuable for detecting minor and incipient denervation. By collating these three electrodiagnostic results, accurate differentiation could be made between physiological block and various degrees of denervation. A statistical analysis of the data obtained confirmed the advantage of early decompression in patients with Bell's and traumatic palsies whose electrodiagnostic findings suggest advanced denervation irreversible by conservative treatment.