In highly selected patients with acute internal carotid artery (ICA) steno-occlusion, prompt restoration might rescue a large ischemic penumbra. We report a 73-year-old man with left hemiparesis, which aggravated with the development of cortical symptoms. MRI & MRA revealed right ICA steno-occlusion and perfusion-diffusion mismatch. The patient underwent emergent carotid endarterectomy and showed clinical improvement without significant complications. The follow-up MRI showed improved perfusion without a new lesion.