Fig 1.

A 72-year-old man presented with subarachnoid hemorrhage secondary to a ruptured anterior communicating artery complex aneurysm. The patient underwent primary endovascular coil treatment of the aneurysm to occlusion.

A, Pretreatment CT scan showing hyperattenuated area mainly in the right Sylvian fissure (arrow).

B, Postprocedural CT scan, obtained 1 hour after the procedure, demonstrating extensive gyriform enhancement of the cerebral cortex, significantly greater on the left (arrowhead).

C, Follow-up CT scan, obtained 11 hours after the procedure, demonstrates resolution of the previously demonstrated gyriform cortical enhancement, with only slight diffuse vasogenic edema shown in the left cortical mantle.