ABSTRACT
Each year, approximately 35,000 people in the United States suffer a subarachnoid hemorrhage (SAH) secondary to a ruptured intracerebral aneurysm. It is estimated that 3.6% to 6% of the general population harbor one or more intracerebral aneurysms, although the exact prevalence is unknown ( 1 ). In patients with known unruptured aneurysms, the annual risk of rupture is approximately 1.3% ( 2 ). Despite progress in the diagnosis and treatment of cerebral aneurysms, 25% to 50% of aneurysmal SAH (aSAH) patients do not survive ( 3 ). Of survivors, only 20% are fully independent after six months ( 4 ). Clinicians have considerable interest in advancing the ability to diagnose and treat aneurysms. A sophisticated understanding of the pathogenesis of aneurysmal formation remains elusive. Intracranial saccular aneurysms are focal dilatations of the arterial wall that typically develop at the apex of a bifurcation in or near the Circle of Willis. Although the prevalence of intracranial aneurysms is unknown, it is estimated that 5% to 8% of the general population harbor these aneurysms, and 15% to 30% of this group have multiple lesions ( 5-9 ).
