A cerebral arteriovenous malformation is an abnormal connection between the arteries and veins in the brain that usually forms before birth.
AVM - cerebral
Causes, incidence, and risk factors
The cause of cerebral arteriovenous malformation (AVM) is unknown. The condition occurs when arteries in the brain connect directly to nearby veins without having the normal vessels (capillaries) between them.
Arteriovenous malformations vary in size and location in the brain.
An AVM rupture occurs because of pressure and damage to blood vessel tissue. This allows blood to leak into the brain or surrounding tissues, and reduces blood flow to the brain.
Cerebral AVMs occur in less than 1% of people. Although the condition is present at birth, symptoms may occur at any age. Hemorrhages occur most often in people ages 15 - 20, but can also occur later in life. Some patients with an AVM also have cerebral aneurysms.
In about half of patiens with AVMs, the first symptoms are those of a stroke caused by bleeding into the brain.
A catheter is guided through a small cut in your groin to an artery and then to the small blood vessels in your brain where the aneurysm is located.
A glue-like substance is injected into the abnormal vessels to stop blood flow in the AVM and reduce the risk of bleeding. This may be the first choice for some kinds of AVMs, or if surgery cannot be done.
Brown RD Jr. Unruptured brain AVMs: To treat or not to treat. Lancet Neurol. 2008;7:195-196.
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.