Ocular vestibular evoked myogenic potential testing for the prognosis of Bell's palsy.

CONCLUSION

oVEMP could be a useful tool for predicting the prognosis of Bell's palsy comparable to ENoG and H-B grade.

OBJECTIVES

Several previous studies have reported cases of Bell's palsy with vestibular function disorder. The basic hypothesis behind this effect lies in the close proximity of the vestibular and facial nerves in the internal auditory canal (IAC). Therefore, the aim of this study was to investigate the correlation between Bell's palsy prognosis and ocular vestibular evoked myogenic potentials (oVEMPs).

METHODS

Total 104 consecutive patients who were diagnosed with Bell?s palsy from January 2012 to December 2014 were enrolled. Patients were divided into complete recovery group and incomplete recovery group. All of patients underwent oVEMP recordings within 1 week after disease onset. For the evaluation of correlation between H-B grades, ENoG, oVEMP and Recovery of Bell?s palsy, logistic regression analysis was performed.

RESULTS

The mean value of ocular vemp asymmetry was significantly higher in the incomplete recovery group than the complete recovery group (p < 0.05). No association was found between the ipsilesional PTA threshold, caloric test, and rate of abnormal EMG and recovery state. However, the initial state of ENoG, initial H-B grade, and oVEMP abnormal findings (Latency & Amplitude symmetry ratio) were significantly correlated with the rate of recovery (p = 0.025, p = 0.013, and p < 0.005, respectively).