[Sudden bilateral hearing loss with vertigo due to vertebral artery occlusion]

We report a case of sudden bilateral hearing loss associated with an occlusion of the right vertebral artery. A 66-year-old man was admitted to hospital suffering from sudden onset vertigo, deafness, and vomiting. He could not walk due to truncal ataxia. There was positional nystagmus to the right; spontaneous and gaze-evoked nystagmus were absent. He had no facial nerve palsy, dysarthria, pyramidal tract signs, limb ataxia, and sensory impairment. Pure tone audiometry demonstrated a profound sensorineural deafness of both ears. A tentative diagnosis of sudden deafness was made. He was treated with intravenous infusion of corticosteroid; hearing loss of the left ear slightly improved. Cranial MR imaging demonstrated fresh small infarcts in the right cerebellar tonsil, the left cerebellar medulla, and the left middle cerebellar peduncle. MR angiography demonstrated an occlusion of the right vertebral artery. It is possible that reduced perfusion of the anterior inferior cerebellar arteries and internal auditory arteries on both sides resulted in multiple "border zone" infarcts and damage to the inner ear. Clinicians should be aware of the possibility of vertebrobasilar occlusive disease in case of sudden bilateral hearing impairment, even when brainstem or cerebellar signs are absent.