A survey of facial paralysis: etiology and incidence.

Facial paralysis has numerous etiologies ranging from the most common, Bell's palsy and trauma, to rare tumors and congenital anomalies. This paper divides the etiologies of facial paralysis into five major classifications: idiopathic, traumatic, infectious, neoplastic and neurologic. The incidence of each of these classifications has been estimated from incidence rate information published in the United States and abroad. Using this information, an estimate of the incidence rate has been determined. This information was previously untabulated, thus making statistical analysis nearly impossible regarding this disorder.