Brain magnetic resonance imaging in the evaluation of lacunar stroke.

Thirty-one patients with presumed lacunar stroke, recent (18 patients) or remote (13 patients), were evaluated with brain magnetic resonance imaging (MRI). MRI detected small, deep lesions appropriate to symptoms in 23 of the patients (74%) and was diagnostically superior to brain computed tomography (CT) in those cases where both studies were obtained acutely. MRI also appeared useful in distinguishing between acute and chronic ischemic lesions. Especially in the setting of suspected acute lacunar infarction, MRI, when available, should replace CT as the diagnostic imaging procedure of choice.