About Arteriovenous Malformation (AVM)
Arteriovenous malformation (AVM) is a tangle of blood vessels that impact blood flow to the affected area of the body. AVMs can occur anywhere but are typically found in the brain or spinal cord. An AVM is not a tumor, but rather a developmental malformation.
The symptoms patients experience depend on the site of the AVM and are related to the lack of oxygen to the area of the malformation. Not all patients will experience AVM symptoms and some AVMs are found incidentally.
Treatment options for AVM include medication, AVM surgery (open-brain, embolization) and stereotactic radiosurgery at a Gamma Knife center. Some patients benefit from a combined approach; the doctor will recommend what he or she feels is right for the individual.
Driven by the heart’s pumping action, the circulatory system moves blood through the body and picks up oxygen from the lungs. The oxygen-rich blood travels through the arterial system (arteries) and delivers oxygen to tissues through tiny vessels (capillaries), then returns through the venous system (veins) to the lungs.
An AVM is a tangle/nest of blood vessels where blood bypasses the capillaries altogether and does not deliver oxygen to the tissues. Most AVM symptoms appear before age 50. Research indicates that genetics may play a role, and a family history of AVM may increase risk.
Symptoms and Diagnosis of AVM
Most AVM patients will not have symptoms. For the 12 percent of patients who experience symptoms, the manifestation depends on the AVM location and usually appear before age 50. If AVM is within the brain, some may experience symptoms that may be stroke-like, including:
- Intracranial hemorrhage
- Hearing and vision disturbances
- Memory issues or difficulty focusing
- Loss of coordination
- Numbness or muscle weakness
Because not all patients experience symptoms, many AVMs are discovered when a doctor orders a test for another reason. These can also confirm a suspected AVM and include:
- Magnetic resonance angiography (MRA): provides pictures of blood vessels, blood flow, and the condition of the vessels’ walls
- Catheter cerebral angiogram: contrast dye is used to analyze blood flow in the brain
- Electroencephalogram (EEG): measures the brain’s electrical activity
- Computed tomography (CT) scan: uses special x-ray equipment to create detailed images of internal organs, bones, soft tissue and blood vessels
- Magnetic resonance imaging (MRI): uses magnetic fields and radio waves to produce a detailed image of the body’s soft tissue and bones
Treatment of AVM
If observation is not recommended, a doctor will recommend a treatment strategy that is best for each individual based on their health history and the location of the AVM. Potential AVM treatment options include:
- Stereotactic Radiosurgery: This procedure uses a focused beam of radiation delivered directly to the AVM without surgery or a hospital stay, using advanced technology such as the Leksell Gamma Knife®Icon™.
- AVM Surgery: The AVM is removed during open surgery if it is in an area that can easily be reached.
- Embolization: The blood vessels are filled with synthetic material to block blood flow, reducing the chance of bleeding.