Cerebellar infarctions mimicking acute peripheral vertigo: how to avoid misdiagnosis?

OBJECTIVE To determine the prevalence of cases of missed cerebellar stroke mimicking acute peripheral vertigo (APV), the so-called pseudo-APV, and to identify the clinical indicators useful for differentiating APV from cerebellar infarction that presents as isolated vertigo. STUDY DESIGN Case series with chart review. SETTING Tertiary referral center. SUBJECTS AND METHODS We conducted a retrospective chart review of cases of missed cerebellar infarction over the past 5 years. All patients had first undergone an otoneurological evaluation and computed tomography brain scan in the emergency department before a complete bedside examination was performed in our otoneurological unit. RESULTS We identified 11 patients with pseudo-APV (2.8% of all the cases presenting to our unit complaining of acute vertigo). Spontaneous nystagmus (of central type in 2 cases) was recorded in all patients. The Head Impulse Test was clearly negative in 9 cases. The duration of vertigo lasted more than 72 hours in 7 patients. In 4 patients, delayed neurological signs followed acute vertigo 2 to 3 days after the onset. Magnetic resonance imaging showed 8 cases of infarction in the posterior-inferior cerebellar artery territory; in 1 patient, an involvement of the anterior-inferior cerebellar artery territory was recorded; 2 patients showed a hemispheric ischemic cerebellar involvement. CONCLUSIONS Pseudo-APV is not an uncommon diagnosis in otoneurological practice. The presence of moderate-severe imbalance and the persistence of vertigo for more than 72 h from the onset, together with the results of bedside examination tests (spontaneous nystagmus and Head Impulse Test), are useful indicators for recognizing a cerebellar ischemic origin in cases of acute vertigo.