A Case of Vestibular and Facial Nerve Root Entry Zone Infarction in AICA Territory Presenting with Vertigo Which Mimics Labyrinthine Lesion

ABSTRACT

Vertigo mimicking labyrinthine lesions may have resulted from ischemic insult to the inner ear or the vestibular nerve and nucleus in the AICA infarction syndrome. A 56-year-old female was admitted to the emergency room with vertigo and hearing loss in right ear. On neurological examination, she had left beating jerky torsional and horizontal nystagmus with falling and past pointing to right side. Brain magnetic resonance images showed high signal intensity in anterolateral portion of inferior pons on T2- weighted images. Severe right facial palsy of peripheral type developed 24 hours after admission. Audiometry and electronystagmography documented absent auditory and vestibular function on the affected side. We argue that vertigo of the acute infarction in AICA territory can be involved the eight and seventh nerve root entry zoon and mimic labyrinthine lesions