Natural history of bell's palsy: The salivary flow test and other prognostic indicators

Abstract

This prospective controlled study included 51 patient with Bell’s palsy evaluated within two days of onset. To determine the natural history of the disease, the patients were followed for six months at which time the amount of facial motor recovery was measured. Sixty-three percent of the patients had complete return while 37 percent had incomplete return. The age of the patients, the presence of pain, and the alteration of taste had no prognostic value. The progression of the palsy, the response to the maximal stimulation test and the results of the salivary flow test were useful prognostic indicators, being approximately 80 percent accurate in predicting the ultimate return of facial function." The salivation test was the most valuable, since salivary flow rates became altered before progression could be detected and earlier than the abnormal response to maximal stimulation. There are reports of surgical decompression based upon loss of electrical stimulation which resulted in incomplete return of facial function, while there have been reports of complete return of facial function when surgery was employed, based upon a reduction in salivary flow to 25 percent or less and before abnormal changes in maximal stimulation occurred. As the findings of a portion of this study showed that steroids did not alter the natural history of Bell’s palsy, a surgical trial for treatment of Bell's palsy is justified, providing surgery is employed based upon a re duction of 25 percent or less in salivary flow and is undertaken before the response to electrical stimulation becomes altered. © The American Laryngological, Rhinological and Otological Society, Inc.