Neuro-otological aspects of cerebellar stroke syndrome

Abstract

Cerebellar stroke is a common cause of a vascular vestibular syndrome. Although vertigo ascribed to cerebellar stroke is usually associated with other neurological symptoms or signs, it may mimic acute peripheral vestibulopathy (APV), so called pseudo-APV. The most common pseudo-APV is a cerebellar infarction in the territory of the medial branch of the posterior inferior cerebellar artery (PICA). Recent studies have shown that a normal head impulse result can differentiate acute medial PICA infarction from APV. Therefore, physicians who evaluate stroke patients should be trained to perform and interpret the results of the head impulse test. Cerebellar infarction in the territory of the anterior inferior cerebellar artery (AICA) can produce a unique stroke syndrome in that it is typically accompanied by unilateral hearing loss, which could easily go unnoticed by patients. The low incidence of vertigo associated with infarction involving the superior cerebellar artery distribution may be a useful way of distinguishing it clinically from PICA or AICA cerebellar infarction in patients with acute vertigo and limb ataxia. For the purpose of prompt diagnosis and adequate treatment, it is imperative to recognize the characteristic patterns of the clinical presentation of each cerebellar stroke syndrome. This paper provides a concise review of the key features of cerebellar stroke syndromes from the neuro-otology viewpoint.

Keywords: cerebellar stroke; head impulse test; hearing loss; pseudo-APV; vertigo.

Fig. 1

MRI finding in a patient with AICA artery territory infarction. T2-weighted MRI scan of the brain demonstrated hyperintense foci involving the left middle cerebellar peduncle. AICA: anterior inferior cerebellar artery.

Fig. 2

MRI finding in a patient with infarction in the territory of the medial branch of the PICA. Diffusion-weighted axial images (A and B) of the brain MRI showed an acute infarct in the left medial caudal cerebellum. PICA: posterior inferior cerebellar artery.

Fig. 3

MRI finding in a patient with infarction in the territory of the medial branch of the SCA. T2-weighted axial (A) and sagittal (B) images of the brain MRI showed an acute infarct involving the rostral paravermal region of the right anterior lobe. SCA: superior cerebellar artery.