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Most common form of Facial paralysis. Clinical features : Pain behind the ear may preced the palsy for one or two days. Onset is abrupt and maximal weakness is attained by 48 hours. Loss of taste sensation unilaterally (on one side). Hyperacusis may be present. Mild cerebrospinal fluid Lymphocytosis may be present. Presence of incomplete paralysis in first week is most favorable sign. 80% patients recover in few weeks to months. Pathophysiology : Bell's palsy is associated with presence of Herpes Simplex type I DNA in endonueral fluid and posterior auricular muscle.This indicates that reactivation of this virus may have some role.However this is not proven yet. Differenctial Diagnosis : Other causes of Facial Palsy - 1. Tumours of temporal bone - Carotid body tumor, Cholesteotoma, Dermoid cysts.The course is insidious and progressive. 2. Ramsay Hunt Syndrome - Due to Herpis zoster of geniculate ganglion.Consists of : Severe facial palsy; eruptions in pharynx, external auditory ca