preview

Intracranial Aneurysm Research Paper

Better Essays

Ruptured Saccular Intracranial Aneurysm associated with Arteriovenous Malformation

Introduction
An arteriovenous malformation (AVM) is an abnormal collection of blood vessels in which arterial blood flows directly into the draining vein without the normal interposed capillaries. AVM are tangled anastomosis of blood vessels of varying calibre in which arteriovenous shunting occurs in a central nidus in which the area towards in which multiple feeding arteries converge and from which enlarged vein drains.1 They have a higher rate of bleeding than normal vessels. AVMs can occur anywhere in the body. Brain AVMs are of special concern because of the damage they cause when they bleed. The incidence of AVM is about 1 in 100,000 per year in unselected …show more content…

Most intracranial aneurysms occur in the cerebral arteries, in which both saccular and fusiform aneurysms are found. Saccular or berry intracranial aneurysm is the most common type and frequent cause of aneurysmal or non-traumatic subarachnoid hemorrhage.6 About 25% of cerebro-vascular deaths are due to ruptured berry aneurysm. Berry aneurysms arise at vessel bifurcation. These aneurysms occur mostly between the ages of 40 and 70 years. Ninety percent of symptomatic berry aneurysms occur in the anterior circulation and 10% in the posterior circulation. In a prospective autopsy study, the mean size of ruptured aneurysms was 8.6 mm and of unruptured was 4.7 mm.7 Several risk factors have been linked with intracranial aneurysm growth and rupture. It includes chronic hypertension, smoking, female gender and African- American ethnicity.8 Smoking has been associated with larger berry aneurysm size and multiple aneurysms.9-11 Alcohol abuse has been associated with aneurysm rupture.11 The role of hypertension in aneurysm formation has been controversial in the literature. Hypertension as a direct cause of aneurysms has never been established, however, it is believed that hypertension may exacerbate a rupture when it occurs and may …show more content…

Another hypothesis is that these associations can accidentally exist together.20 Among these hypothesis, the hemodynamic stress secondary to the increased blood flow of AVM plays a significant role to provoke this coexistence of lesion.1,21 This hypothesis is supported by a report showing that the associated aneurysms tend to be concentrated in feeding arteries which supply AVM and the associated aneurysms may shrink in proportion to the occlusion of the AVM. 3
The incidence of intracranial aneurysms is higher in patients with intracranial AVM than in the general population. This incidence varies from 2.7 to 23% in the literature.1, 22 Four types of aneurysms occur in association with AVM are: [1] Unassociated aneurysms: this type of aneurysm occurs on the circle of Willis in a location that is not associated hemodynamically with the

Get Access