Abstract: There is only three reports on the frequency of audio vestibular involvement in BD in the literature. In these studies, done in small population of BD patients, the frequency of auditory involvement were reported as high as 60%, and the vestibular involvement between 25 to 37%. We studied prospectively the audio vestibular involvement in 80 patients with BD, and compared them with 102 controls (CG) including hospital staffs, patients with ...