Arteriovenous Malformation: improperly formed blood vessels. If in brain, seizure, headache, stroke-like symptoms may occur.
An arteriovenous malformation, or AVM, is a knot of abnormal and poorly formed blood vessels, like arteries and veins. They have a high tendency to bleed, so while AVMs can form in any part of the body, the potential for bleeding makes AVMs that form in the brain potentially very dangerous. The brain and its arteries are formed at the same time during embryological development; therefore, abnormal formations of blood vessels are usually associated with abnormal brain tissues. As a result, AVMs are also associated with abnormalities of the brain tissues.
The size and location of AVMs vary in the brain. AVMS affect less than one percent of the population. Although AVMs are believed to develop before or shortly after birth, their symptoms may appear at any age.
The causes of arteriovenous malformations are not yet fully known. Arteries are connected to veins by structures called capillaries. AVMs are formed when arteries connect to veins without the presence of capillaries.
AVMs can rupture from pressure, which can damage the tissues of the blood vessels. This results in blood escaping from the vessels and leaking into the brain and surrounding tissues. The flow of blood to the brain is reduced as a result of this bleeding.
The symptoms depend on the size and location of the arteriovenous malformation. An AVM may not exhibit any symptoms in some cases. Possible symptoms include:
The following tests may be used to help your doctor diagnose and determine the best treatment options for arteriovenous malformations:
The type of treatment is based upon the size and location of the AVM. The following treatment options are available: