ABSTRACT
Cerebral vasospasm can be defi ned in terms of angiographic fi ndings or clinical signs. Ecker and Riemenschneider fi rst described angiographic vasospasm in 1951 ( 1 ). Angiographic vasospasm can be detected in up to 70% of patients following subarachnoid hemorrhage (SAH) ( 2 ). Clinically, cerebral vasospasm usually starts 3 to 5 days following SAH, exhibits maximal narrowing between days 5 and 14, and gradually resolves over 2 to 4 weeks ( 3 ). Clinical cerebral vasospasm, or neurologic deterioration due to cerebral ischemia, is less common and develops in 20% to 30% of patients with SAH.
