Arteriovenous Malformations

Arteriovenous malformations (AVMs) are abnormal tangles of arteries and veins that grow in the brain. The malformation can form wherever there are arteries or veins in the brain or spinal cord and they are the leading cause of hemorrhagic strokes in children and adolescents.

AVMs, which belong to a group of disorders known as vascular malformations, typically develop in the womb or soon after birth. Although not completely understood, they may be linked to genetic mutations.

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Arteries carry oxygen-rich blood away from the heart to the body's cells and veins return oxygen-depleted blood to the lungs and heart. When AVMs disrupt this process, they can reduce the amount of oxygen received by brain tissues. This can lead to the compression of parts of the brain or spinal cord. The most severe risk of AVM is bleeding, called a hemorrhage, in the brain, which can lead to a debilitating or fatal stroke.

AVMs of the brain or spinal cord affect about 300,000 Americans. Occurring equally in males and females from all ethnic and racial backgrounds, symptoms are more common in children over 9-years-old than those who are younger.

AVMs are treated at the UCSF Pediatric Stroke and Cerebrovascular Disease Center, the only comprehensive cerebrovascular disease center for children in the country staffed by the world's leading experts in pediatric stroke and cerebrovascular disease.

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Children who are born with arteriovenous malformations (AVMs) may not experience symptoms for many years. In fact, symptoms may occur anywhere between age 10 and 40.

Symptoms, however, can occur at any age, as in the most severe forms of the disease, called a Vein of Galen Malformation. This condition may cause symptoms at birth or very soon after. Symptoms may include swelling of the brain, seizures, failure to thrive, congestive heart failure and swollen veins.

Each child may experience symptoms differently, depending on the location of the AVM. Some of the most common symptoms include:

  • Abnormal sensations, such as numbness, tingling or spontaneous pain
  • Dizziness
  • Headache, varying in severity, duration and intensity
  • Loss of coordination, known as ataxia
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The following tests may be used to determine if your child has an arteriovenous malformation (AVM) as well as to help identify its size, location and blood-flow pattern.

  • Angiogram — This is an important test in the diagnosis of AVM and involves a special X-ray exam that enables a radiologist, a doctor who specializes in understanding and interpreting X-rays, to study your child's blood vessels. The radiologist will insert a small tube, called a catheter, into the blood vessel and then inject a special dye that makes the vessels visible on the X-rays. This will allow the radiologist to observe how the blood travels through the blood vessels of the brain. The procedure takes about one hour.
  • Computed Tomography (CT) — A CT scan is a method of body imaging in which a thin X-ray beam rotates around the patient. It can be used to detect the presence of blood in the brain.
  • Magnetic Resonance Imaging (MRI) — An MRI scan can detect if there is blood in the brain. It is a non-invasive procedure that uses powerful magnets and radio waves to construct pictures of the body.

Our experts — among the best in the world — will work with you and your family to develop the best possible treatment plan for your child. This team includes a neurologist, neurosurgeon, neurointerventional radiologist and radiation oncologist.

Because arteriovenous malformations (AVMs) are one of the leading causes of debilitating hemorrhagic strokes in young people, the goal of treatment is to reduce the risk of stroke. Today, there are many safe and highly effective therapies. These include surgery, radiation therapy, embolization and radiosurgery using a machine called a Gamma Knife.

  • Surgery — In many cases, surgery may be recommended to completely remove your child’s AVM. In addition to conventional brain surgery, advanced, minimally invasive surgical techniques are available.
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Reviewed by health care specialists at UCSF Benioff Children's Hospital.

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UCSF Clinics & Centers

Pediatric Brain Center

Intensive Care Nursery
1975 Fourth St., Third Floor
San Francisco, CA 94158
Phone: (415) 353-1565
Fax: (415) 353-1202

Neuro-Intensive Care Nursery (NICN)
1975 Fourth St., Third Floor
San Francisco, CA 94158
Phone: (415) 353-1565
Fax: (415) 353-1202

Stroke & Cerebrovascular Disease Center
1825 Fourth St., Fifth Floor
San Francisco, CA 94158
Phone: (415) 353-7596
Fax: (415) 353-2400
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