MRI More Sensitive Than CT for Evaluating Posterior Circulation Stroke

Background: Dizziness is a common presentation to the emergency department (ED), and posterior circulation stroke is a significant concern. However, ≤40% of strokes are missed in these patients. The most common imaging screening tool is CT with CT angiography (CTA) of the head and neck. However, this has a low sensitivity for stroke of 16% to 40%. Standard MRI with diffusion-weighted images (DWIs) with a slice thickness of 4 to 6 mm has a sensitivity of double that at 80%. However, high-resolution multiplanar DWI at 3-mm slice thickness has a sensitivity of 95%. Objective: To compare changes in management that occur when using MRI rather than CT with CTA (CT/CTA) to evaluate patients presenting to the ED with dizziness. Design: Retrospective study. Methods: 1917 patients presenting to the ED with the complaint of dizziness, at a single institution during a 4-year period, were included. Propensity score matching analysis was used to compare patients who were discharged after CT/CTA more...