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Arteriovenous malformation

An arteriovenous malformation (AVM) is a tangle of abnormal blood vessels connecting arteries and veins in the brain. Normally, the arteries carry oxygen-rich blood from your heart to your brain, and the veins take the oxygen-deleted blood back to the lungs and heart. AVMs – which occur in the brain or spine – can bleed into the brain if it ruptures. They are very rare, effecting only 1 percent of the U.S. population. Most people with an AVM are born with the condition, though an AVM can occur later in life, and the cause is mostly unknown.


  • Headache
  • Seizures
  • Weakness or numbness of limbs
  • Aneurysm



Computed tomography scan (CT or CAT scan) uses a combination of X-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan is more detailed than general X-rays and shows detailed images of any part of the body, including the bones, muscles, fat and organs.

Magnetic resonance imaging (MRI) uses large magnets attached to a computer to produce detailed images of organs and structures within the body.


Microsurgery involves removing the AVM surgically. Several factors are considered before this surgery is performed, including the size and location of the AVM, your age and overall health.

Stereotactic radiosurgery delivers a single or multiple doses of radiation in a precisely focused way without surgery. This procedure causes the blood vessels to thicken and close off over a period of time, usually over 18 months to two years. Stereotactic radiosurgery may be used for small AVMs (less than 3 cm), particularly if the AVM is in a deep location or if you are not a candidate for surgery.

Embolization involves placing a small tube into the abnormal arteries feeding the AVM and injecting a glue-like material into the arteries to block them. This procedure is done in an effort to shrink an AVM before performing other treatments, such as surgery or stereotactic radiosurgery, and can also be used as primary treatment.