Study on Prognostic Value of Electrophysiological Tests in Bell’s Palsy

ABSTRACT

Introduction: Bell’s palsy is an idiopathic peripheral disease of the seventh cranial nerve. More than 70% of patients attaincomplete clinical recovery, with no noticeable residua. Electrophysiological tests may offer valuable information in defining theseverity of nerve injury and a possible subsequent dysfunction.Aim: This study aims to assess the prognostic value of electrophysiological tests in the management of Bell’s palsy.Materials and Methods: All the patients with Bell’s palsy and without clinical evidence of other cranial nerve damage or centralnervous system diseases were included in the study. Nerve conduction study was performed on the 14th day or on the firstvisit of the patient to the hospital.Results: In 101 patients, majority of patients come under Grade IV (43.6%) and next comes Grade V (31.7%). Eighty-twopatients (81.2%) had normal latency, among these, 73 cases recovered within 6 months. Of 17 who had prolonged latency,seven patients recovered fully.Conclusions: Electrophysiological studies can predict the duration of the clinical recovery and the outcome of the illness. Theamplitude ratio of compound muscle action potential is the most reliable parameter in assessing the prognosis.