[Diagnosis and treatment of facial palsy]

The topographic diagnosis of facial nerve lesions is based on the symptoms that accompany paralysis, allowing lesions to be located in the protuberance, pontocerebellar angle, facial channel or trajectory distal to the stylomastoid foramen. Most cases of peripheral facial palsy have no apparent cause (idiopathic, or Bell's, peripheral facial palsy). However, facial palsy can sometimes be a manifestation of neuroborreliosis, multiple sclerosis, diabetes, HIV infection or neurinoma. Neurophysiologic studies complement physical examination to establish a prognosis; after the fifth day axonal degeneration related to incomplete recovery can be recognized. Magnetic resonance identifies nerve lesions but is useful only in atypical cases. Prednisone 1 mg/kg over 5 days, with gradual weaning, is the most widely accepted treatment for Bell's palsy. Acyclovir is indicated in Ramsay-Hunt syndrome. Early surgical decompression in cases with poor prognosis is not generally considered beneficial. Cases of permanent facial palsy have serious consequences, particularly because facial expression is altered.