[MR imaging of brainstem infarction].

Thirty-three patients with old brainstem infarct were studied with MR imaging at 1.5T. T1-weighted images were most useful for diagnosing brainstem infarct. Brainstem infarcts were most frequently observed at the central portion of the mid pons. All of the lesions of three patients with medullary infarct were right sided. Both of the lesions of two patients with midbrain infarct were relatively large. Brainstem infarcts frequently accompanied supratentorial lacunar infarcts and subcortical arteriosclerotic encephalopathy.