title: Aneurysms: intracranial aneurysms.
abstract: Intracranial aneurysms (IAs) are found in 3.2% of the general population and most commonly are diagnosed in individuals at a mean age of 50 years. Most IAs occur in the internal carotid circulation. When an IA ruptures and causes subarachnoid hemorrhage, patients typically present with severe thunderclap headaches. When aneurysmal rupture is suspected, noncontrast computed tomography scan of the head is indicated. If subarachnoid hemorrhage is confirmed, the patient should be referred to a center that offers neurosurgical and critical care for short- and long-term management. A computed tomography angiogram is then obtained to define anatomy. Nonoperative components of management include blood pressure control, antifibrinolytics, calcium channel blockers, statins, and an anticonvulsant for seizure prophylaxis. Definitive treatment involves endovascular procedures (eg, coil embolization) or microvascular surgery (eg, clipping the base of the aneurysm), with the choice depending on patient age, comorbidities, and IA anatomy. In some patients, aneurysms are detected before rupture, such as via imaging studies obtained for other reasons. In such cases, monitoring of unruptured anterior circulation IAs with interval magnetic resonance angiography is recommended if the aneurysm is smaller than 7 mm. Larger IAs and posterior circulation IAs typically warrant endovascular or microvascular procedures to prevent subarachnoid hemorrhage.
authors: University of Oklahoma Health Sciences Center Department of Neurosurgery, 1000 N Lincoln Blvd Suite 4000, Oklahoma City, OK 73104, bradley-bohnstedt@ouhsc.edu.
authors: Bradley N
authors: BN
authors: Bohnstedt
authors: Goodman Campbell Brain and Spine Department of Neurological Surgery, 355 W 16th St Suite 5100, Indianapolis, IN 46202, acohenmd@gmail.com.
authors: Aaron A
authors: AA
authors: Cohen-Gadol