Subarachnoid hemorrhage.

Subarachnoid hemorrhage (SAH) can result from the rupture of an intracranial aneurysm-a weakened, dilated area of a blood vessel in the brain that is prone to burst. SAH can be devastating. Approximately 1 in 6 patients dies at the time of the bleeding. Those who initially survive can die after early rebleeding or have major complications. The complications of SAH include strokes from delayed spasm of blood vessels in the brain even after the aneurysm that caused the hemorrhage is treated. Most of the research on SAH has been focused on this early phase. Less is known about what happens longer term to those patients who survive SAH.