Fig 2.

An 88-year-old woman status post surgical clipping of a left posterior communicating artery aneurysm. On day 7, she developed left upper and lower extremity motor deficits. Initial noncontrast CT (not shown) revealed no evidence of acute infarction, new hemorrhage, or hydrocephalus to explain the new onset of symptoms. CTP demonstrates a large right-sided perfusion deficit with elevated MTT (A) and reduced CBF (B) in the right MCA territory (arrows). Noncontrast CT (C) performed on day 21 shows an infarction involving the right insular region (arrows) corresponding to the CTP deficit.