A 59-year-old man developed sudden left hemiparesis and dysarthria 35 min before arrival at the emergency room. He was a current smoker. He had facial palsy, hemiparesis and sensory extinction on the left side. His baseline National Institutes of Health Stroke Scale score was 9. The right radial pulse was diminished. An initial diffusion weighted image showed areas of subtle diffusion restriction in the right middle cerebral artery (MCA) territory (fig 1A). CT angiography after administration of intravenous tissue plasminogen activator demonstrated right distal MCA stem occlusion (fig 1B). Intra-arterial thrombolysis was attempted 4 h after the onset of symptoms.