Morbidity and mortality associated with intracranial aneurysms.

Subarachnoid hemorrhage (SAH) is bleeding into the subarachnoid space. It may result from a rupture of an intracranial aneurysm, bleeding from an arteriovenous malformation, hypertensive intracerebral hemorrhage with extension into the subarachnoid space, hemorrhage from an intracranial tumor, trauma, and hematologic disorders. If trauma is eliminated as a cause of SAH, more than 80% of SAHs are due to rupture of an intracranial aneurysm. This paper will focus on morbidity and mortality associated with ruptured and unruptured intracranial aneurysms.