Of every 100 people who have an arteriovenous malformation, or AVM, of the brain, about four will experience bleeding in a given year. The cumulative risk of bleeding from an AVM over a person’s lifetime can be high, so getting the right arteriovenous malformation treatment is important.
Microsurgical resectioning to completely remove this tangle of abnormal blood vessels is one highly effective option. Depending on the size and location of the AVM and other factors, less invasive procedures such as embolization or stereotactic radiosurgery can also be used to successfully treat your condition.
Why Should an AVM Be Treated?
An arteriovenous malformation is an abnormal collection of blood vessels that connects arteries and veins, while bypassing the capillaries, or the small blood vessels responsible for carrying oxygenated blood to the tissues. Blood flows rapidly and at a high volume through the weakened, thin walls of these malformed vessels, raising the risk of leaking or rupture.
AVMs can develop in the brain, spinal cord or other parts of the body. They may be caused by a problem with the formation of blood vessels in the womb or by an inherited condition. The exact cause as to why they develop is currently not known. As an AVM enlarges or begins to bleed, you might experience stroke-like symptoms such as headaches, seizures, weakness or paralysis on one side of the body. It’s also possible to experience problems with your vision, balance, memory or hearing.
Symptoms can vary, depending on the location of the AVM in the brain. Smaller AVMs might not cause symptoms at all and are typically discovered in the course of treating another condition. But because any AVM poses a risk of bleeding, arteriovenous malformation treatment focuses on eliminating that risk by removing or blocking the abnormal vessels. You and your doctor will work together to determine the best course of treatment, depending on the size and location of your AVM, your overall health and any other relevant factors.
Microsurgical Resection for AVMs
Surgical resection is a highly effective arteriovenous malformation treatment that removes the AVM completely. The abnormal blood vessels don’t grow back, so surgery can eliminate the risk of future bleeding.
Surgery is performed in a hospital under general anesthesia and requires a craniotomy, a procedure to open the skull so that surgeons can reach the AVM. Each vessel leading to the abnormal tangle is clamped off, and the entire AVM is removed, leaving all brain tissue intact. Depending on circumstances, your surgeons may perform an embolization procedure a day or so before surgery to reduce blood flow to the AVM. During the surgery, while you are asleep, an angiogram will be performed to check the surgery site and make sure that all blood vessels were successfully removed.
After surgery, you’ll be monitored in the ICU for a day or so and remain hospitalized for a couple days. Recuperation at home takes about a month.
Although surgery can eliminate an AVM entirely, this procedure may not be the right choice for everyone. Some AVMs are located deep in the brain where surgery becomes risky or impossible, or they may be small enough that they can be resolved with less invasive treatments.
Catheter Embolization for AVMs
Catheter embolization is a minimally invasive arteriovenous malformation treatment in which a catheter is inserted through a small incision in the groin and directed to the site of the AVM in the brain. Once the catheter is in place, an embolizing, or blocking, agent such as medical glue, a metal coil or mesh is placed into the AVM to close up the abnormal connections.
Embolization is also performed in a hospital, but this procedure typically takes less than a day and you’re likely to be released within 24 hours. Embolization can be used to completely seal the AVM, or it might be used to reduce the blood flow to a very large AVM before surgery to remove it.
Stereotactic Radiosurgery for AVMs
Stereotactic radiosurgery is a completely nonsurgical arteriovenous malformation treatment for smaller AVMs and those located in areas of the brain where surgery isn’t appropriate. Noninvasive and completed in less than one hour, radiosurgery delivers a focused dose of gamma radiation directly to the abnormal cluster of vessels.
This burst of radiation damages the walls of the AVM’s blood vessels, causing them to thicken, but that process is slow. It can take two or three years for the AVM to completely close and eliminate the risk of bleeding in the brain. While the AVM is closing, the risk of bleeding still exists, so those who have radiosurgery typically need regular follow-ups for monitoring the status of the AVM.
Although the stereotactic radiosurgery procedure itself may be brief, preparations can require you to be in a hospital for several hours. Your doctors will need to perform a variety of imaging procedures in order to pinpoint your AVM and determine a treatment plan. Radiation is painless, but you may have side effects such as headaches or nausea after treatment. There can be also side effects that occur much later in life and are related to radiation injury. For most people, there’s no need for hospitalization after radiosurgery.
Treatment Options – What’s Best For You?
Microsurgical resectioning can successfully eliminate arteriovenous malformations, but many AVMs can be treated without an invasive brain procedure through stereotactic radiosurgery — or with minimally invasive catheter embolization. Every situation is unique, so you and your doctors will work together to find the arteriovenous malformation treatment that’s right for you.
