Ateriovenous Malformation (AVM)

Though quite uncommon, a malformation of spinal blood vessels called an ateriovenous malformation (AVM) can cut off blood supply to spinal tissue or the spinal cord. Like a cord that gets tangled and can't reach the wall outlet, this tangle of blood vessels wraps around itself and does not reach the tissue the vessels are intended to supply. In addition to causing the spinal tissue to die from lack of oxygen and putting pressure on the spinal cord or nerve roots, AVMs present a risk of rupturing and causing a life-threatening hemorrhage.

About 88 percent of AVMs cause no symptoms at all and are only discovered when the patient undergoes testing for another condition. In the remaining 12 percent, symptoms can range from mild discomfort to severe pain, and from slight neurological abnormalities to weakness or numbness in the arms and legs.

If an AVM is suspected, spinal imaging is used to verify and map out the AVM location and structure. Imaging may include Magnetic Resonance Angiogram (MRA), magnetic resonance imaging (MRI) of the spine or computed tomography (CT) scan of the spine.

Because of the possible harm AVMs can cause, they are aggressively treated whenever possible. Surgical techniques through the Sutter Neuroscience Institute may include Endovascular Surgical Neuroradiology, Gamma Knife Radiosurgery and traditional surgery techniques.

For a more complete discussion, see our Healthwise health information section on arteriovenous malformation or visit the National Institute of Neurological Disorders and Stroke section on arteriovenous malformations (AVMs).