Axial FLAIR (A), T1 precontrast (B), T1 postcontrast (C), and diffusion-weighted (D) MRI showing a T2-hyperintense (A), mildly expansile lesion in the right frontal lobe with patchy enhancement (C) and no evidence of restricted diffusion. The differential diagnosis included high-grade glioma and subacute infarction. CT angiography (not shown) demonstrated near-total occlusion of the right proximal internal carotid artery. Follow-up MRI 5 weeks later (E, F) demonstrated evolving volume loss and encephalomalacia in the right frontal lobe (E) as well as decreased enhancement (F) consistent with chronic right frontal infarct.
