Infarction in the territory of anterior inferior cerebellar artery: spectrum of audiovestibular loss.

BACKGROUND AND PURPOSE To define the detailed spectrum of audiovestibular dysfunction in anterior inferior cerebellar artery territory infarction. METHODS Over 8.5 years, we prospectively identified 82 consecutive patients with anterior inferior cerebellar artery territory infarction diagnosed by MRI. Each patient completed a standardized audiovestibular questionnaire and underwent a neuro-otologic evaluation, including bithermal caloric tests and pure tone audiogram. RESULTS All but 2 (80 of 82 [98%]) patients had acute prolonged vertigo and vestibular dysfunction of peripheral, central, or combined origin. The most common pattern of audiovestibular dysfunction was the combined loss of auditory and vestibular function (n=49 [60%]). A selective loss of vestibular (n=4 [5%]) or cochlear (n=3 [4%]) function was rarely observed. We could classify anterior inferior cerebellar artery territory infarction into 7 subgroups according to the patterns of neuro-otological presentations: (1) acute prolonged vertigo with audiovestibular loss (n=35); (2) acute prolonged vertigo with audiovestibular loss preceded by an episode(s) of transient vertigo/auditory disturbance within 1 month before the infarction (n=13); (3) acute prolonged vertigo and isolated auditory loss without vestibular loss (n=3); (4) acute prolonged vertigo and isolated vestibular loss without auditory loss (n=4); (5) acute prolonged vertigo but without documented audiovestibular loss (n=24); (6) acute prolonged vertigo and isolated audiovestibular loss without any other neurological symptoms/signs (n=1); and (7) nonvestibular symptoms with normal audiovestibular function (n=2). CONCLUSIONS Infarction in the anterior inferior cerebellar artery territory can present with a broad spectrum of audiovestibular dysfunctions. Unlike a viral cause, labyrinthine dysfunction of a vascular cause usually leads to combined loss of both auditory and vestibular functions.