Intracranial aneurysms

An intracranial aneurysm is an acquired dilatation of the vessel wall of a cerebral artery. Most remain asymptomatic, but some can rupture, causing an aneurysmal subarachnoid haemorrhage (aSAH). This is a devastating subset of stroke with a poor outcome. Screening for unruptured intracranial aneurysms can prevent future aSAH by early detection and preventive treatment of identified aneurysms. Screening should ideally only be done in persons in whom a high lifetime risk of aSAH outweighs the risk of complications of preventive treatment and the potential negative effects of screening on quality of life. Screening has been shown effective for persons with a positive family history for aSAH. However, this group constitutes only a minority of all patients with aSAH. Therefore, more persons with an increased risk of aSAH should be identified. Also, more information on predictors of aneurysm rupture is needed to further improve prevention of aSAH. This thesis presents the yield of screening for intracranial aneurysms in two groups of persons with a potentially increased lifetime risk of aSAH. Also, the course and predictors of the effect of screening on quality of life are described. Last, the rupture risk of familial intracranial aneurysms is determined, and patient and aneurysm related characteristics potentially contributing to this risk are studied. This information can be used to improve counselling on screening for intracranial aneurysms. In addition, our findings can contribute to the reduction of the number of life years in good quality being lost through aSAH, by improving screening for intracranial aneurysms and prediction of aSAH.