Unilateral cystic inner ear anomalies in siblings.

Unilateral cystic inner ear anomalies were diagnosed in two siblings, a 9 year old boy and a 6 year old girl. X-ray examination of the temporal bone was performed, together with audiological examinations and vestibular function tests. The common tomographic X-ray findings consisted of an enlarged solitary sac type deformity of the vestibule with narrowing of the internal auditory canal, severe hypoplasia of the anterior semicircular canal and no visualized cochlea. Pure-tone audiometry revealed severe mixed type of hearing loss in the right ear in both children. The test for vestibular function showed no response to caloric testing.