Prognostic factors of synkinesis after Bell's palsy and Ramsay Hunt syndrome

Abstract

This study evaluated the prognostic factors of synkinesis following Bell's palsy and Ramsay Hunt syndrome. A total of 345 patients consisting of 309 cases of Bell's palsy and 36 cases of Ramsay Hunt syndrome were enrolled in our study. The following 13 factors were considered as candidate prognostic factors for the presence of synkinesis at 6 months from onset: age, sex, diagnosis, diabetes mellitus, initial onset or recurrence, electroneurography (ENoG), number of days from onset to first visit to our hospital, the lowest Yanagihara grading system score, the change in Yanagihara score after 1 month, otalgia, hearing loss, vertigo and taste disturbances. These factors were analyzed by logistic regression. Logistic regression analysis clarified the lowest Yanagihara score, the change in Yanagihara score after 1 month, and the ENoG value for a prognosis of synkinesis. The most predictive prognostic factor was the lowest Yanagihara score, and the adjusted odds ratio in the multivariate model was 11.415. As for other prognostic factors, the adjusted odds ratios ranged from 7.017 (ENoG value) to 8.310 (the change in Yanagihara score after 1 month). These findings were therefore considered as high risk factors for synkinesis. It is possible to predict synkinesis following Bell's palsy and Ramsay Hunt syndrome on the basis of clinical symptoms. The lowest Yanagihara score, and the change in Yanagihara score after 1 month, together with the ENoG value at the onset, were found to be especially important factors for predicting synkinesis following Bell's palsy and Ramsay Hunt syndrome.