Audiological signs in pediatric cases with dehiscence of the bony labyrinth caused by a high jugular bulb.

Clinical findings were assessed in three pediatric cases of dehiscence of the bony labyrinth caused by a high jugular bulb (HJB). Two children had two dehiscent lesions, which included posterior semicircular canal dehiscence (PSCD) and vestibular aqueduct dehiscence (VAD). One child had VAD alone. Two subjects with PSCD, but not with VAD alone, had mixed hearing loss and showed wave motion of the baseline on tympanometry and acoustic reflex testing, and a reduced response on otoacoustic emission. These findings may reflect jugular venous pulsations transmitted through the PSC and represent characteristics of cases with PSCD caused by HJB.