MRI-Negative Strokes in Patients with Severe, Persistent Vertigo

Most causes of vertigo are benign, but stroke may present with vertigo as the only symptom. Clinicians rely on magnetic resonance imaging (MRI) as a sensitive tool for ruling out stroke, but prior studies have highlighted its limited sensitivity for small brainstem strokes within the first few days after onset. Investigators have now performed a retrospective study to characterize strokes presenting predominantly with vertigo and not initially detected by MRI.

During a 13-year period at a referral center, 105 patients presented with stroke manifesting as acute vestibular syndrome (days to weeks of continuous vertigo or dizziness, nausea or vomiting, head-motion intolerance, gait unsteadiness, and nystagmus). Stroke was confirmed by follow-up imaging in cases of high clinical suspicion and negative early imaging.

Fifteen patients (14%) had small infarcts (≤10 mm). These small infarcts most often involved the inferior cerebellar peduncle (73%) and the lateral medulla (60%). Early MRI (performed within 6–48 hours after symptom onset) was 47% sensitive for small infarcts and 92% sensitive for infarcts >10 mm. Detailed bedside examination consisting of the HINTS “plus” battery of tests (head impulse, nystagmus, test-of-skew, and bedside hearing by finger rub) was ≥99% sensitive for small and large infarcts.