NINDS Arteriovenous Malformation Information Page

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Condensed from Arteriovenous Malformations and Other Vascular Lesions of the Central Nervous System Fact Sheet

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What is Arteriovenous Malformation?

Arteriovenous malformations (AVMs) are defects of the circulatory system that are generally believed to arise during embryonic or fetal development or soon after birth.  Although AVMs can develop in many different sites, those located in the brain or spinal cord can have especially widespread effects on the body.  Most people with neurological AVMs experience few, if any, significant symptoms.  The malformations tend to be discovered only incidentally, usually either at autopsy or during treatment for an unrelated disorder. But for about 12 percent of the affected population (about 36,000 of the estimated 300,000 Americans with AVMs), these abnormalities cause symptoms that vary greatly in severity.  Seizures and headaches are the most generalized symptoms.  AVMs also can cause a wide range of more specific neurological symptoms that vary from person to person, depending primarily upon the location of the AVM.  Such symptoms may include muscle weakness or paralysis, loss of coordination, difficulties carrying out tasks that require planning, dizziness, visual disturbances, problems using or understanding language, abnormal sensations (such as numbness, tingling, or spontaneous pain), memory deficits,  mental confusion, hallucinations, or dementia.

Is there any treatment?

Medication can often alleviate general symptoms such as headache, back pain, and seizures caused by AVMs and other vascular lesions. However, the definitive treatment for AVMs is either surgery or focused irradiation therapy.  The decision to perform surgery on any individual with an AVM requires a careful consideration of possible benefits versus risks.  Because so many variables are involved in treating AVMs, doctors must assess the danger posed to individual patients largely on a case-by-case basis.

What is the prognosis?

The greatest potential danger posed by AVMs is hemorrhage. Researchers believe that each year between 2 and 4 percent of all AVMs hemorrhage. Most episodes of bleeding remain undetected at the time they occur because they are not severe enough to cause significant neurological damage. But massive, even fatal, bleeding episodes do occur. Whenever an AVM is detected, the individual should be carefully and consistently monitored for any signs of instability that may indicate an increased risk of hemorrhage.

What research is being done?

The National Institute of Neurological Disorders and Stroke (NINDS) conducts research related to AVMs in its laboratories at the National Institutes of Health (NIH) and also supports additional AVM research through grants to major medical institutions across the country.  A group of NINDS-sponsored researchers is currently studying large populations of patients with AVMs to formulate criteria that will allow doctors to predict more accurately the risk of hemorrhage in individual patients.  Other scientists are seeking to refine the techniques now available to treat AVMs.  Several ongoing studies are devoted to developing new noninvasive neuroimaging technologies to increase the effectiveness and safety of AVM surgery.

NIH Patient Recruitment for Arteriovenous Malformation Clinical Trials

Organizations

National Organization for Rare Disorders (NORD)
P.O. Box 1968
(55 Kenosia Avenue)
Danbury, CT   06813-1968
orphan@rarediseases.org
http://www.rarediseases.org
Tel: 203-744-0100 Voice Mail 800-999-NORD (6673)
Fax: 203-798-2291

International RadioSurgery Association
3002 N. Second Street
Harrisburg, PA   17110
office1@irsa.org
http://www.irsa.org
Tel: 717-260-9808
Fax: 717-260-9809

Related NINDS Publications and Information
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Prepared by:
Office of Communications and Public Liaison
National Institute of Neurological Disorders and Stroke
National Institutes of Health
Bethesda, MD 20892



NINDS health-related material is provided for information purposes only and does not necessarily represent endorsement by or an official position of the National Institute of Neurological Disorders and Stroke or any other Federal agency. Advice on the treatment or care of an individual patient should be obtained through consultation with a physician who has examined that patient or is familiar with that patient's medical history.

All NINDS-prepared information is in the public domain and may be freely copied. Credit to the NINDS or the NIH is appreciated.

Last updated December 11, 2007