A spinal arteriovenous malformation (AVM) is a tangle of blood vessels that forms on, in or near the spinal cord. This creates irregular connections between arteries and veins. Without treatment, this rare condition can cause lasting damage to the spinal cord.
Oxygen-rich blood enters the spinal cord through arteries. The arteries usually branch into smaller blood vessels called capillaries. The spinal cord gets oxygen from the blood in the capillaries. Then the blood passes into veins and moves away from the spinal cord to the heart and lungs.
But in a spinal AVM, the blood passes directly from the arteries to the veins. This change in blood flow means that the surrounding cells don't get the oxygen they need. This can cause cells in the spinal tissue to weaken or die.
The tangled arteries and veins in a spinal AVM also can burst and cause bleeding in the spinal cord. Sometimes, the AVM gets bigger as blood flow increases. The AVM can press on the spinal cord and cause weakness or other symptoms.
You might not know you have a spinal AVM unless you have symptoms. The condition can be treated with surgery to stop or possibly reverse some of the spinal damage.
Symptoms of a spinal arteriovenous malformation (AVM) can differ from person to person. Symptoms depend on where the AVM is found and how serious it is. Some people may not notice symptoms for many years, if at all. Others may experience symptoms that are life-threatening.
Symptoms often begin when people are in their 20s but can occur at earlier or later ages. Some people are diagnosed under the age of 16.
Symptoms may start suddenly or slowly and may include:
As the condition gets worse, you may have more symptoms including:
Make an appointment with your healthcare professional if you experience symptoms of a spinal AVM.
The cause of spinal arteriovenous malformations (AVMs) isn't known. Most spinal AVMs are present at birth, known as congenital. But others may happen later in life.
There are no known risk factors for spinal arteriovenous malformations (AVMs). The condition occurs equally in men and women.
Without treatment, a spinal arteriovenous malformation (AVM) can cause disability that gets worse over time. This is from damage to the spinal cord and surrounding tissues. This can cause:
Spinal arteriovenous malformations (AVMs) can be hard to diagnose. The symptoms are similar to those of other spinal conditions. Other conditions may include spinal dural arteriovenous fistula, spinal stenosis, multiple sclerosis or a spinal cord tumor.
Your healthcare professional may recommend tests to help rule out other causes of your symptoms, including:
Angiography, which often is needed to see the location and characteristics of the blood vessels involved in the AVM.
In an angiography, a thin tube called a catheter is inserted into an artery in the groin. It's guided to the spinal cord. Dye is injected into blood vessels in the spinal cord to make them visible under X-ray imaging.
Treatment for a spinal arteriovenous malformation (AVM) may involve a combination of approaches. Treatment can lessen symptoms and lower the risk of possible complications. The choice of treatment depends on the size, location and blood flow of the spinal AVM. The results of your neurological exam and your overall health also are taken into account.
The goal of spinal AVM treatment is to lower the risk of the AVM bleeding. Treatment also can stop or prevent disability and other symptoms from getting worse.
Pain-relieving medicines may be used to reduce symptoms such as back pain and stiffness. But most spinal AVMs may eventually need surgery.
Surgery is often needed to remove a spinal AVM from the surrounding tissue. There are three ways to remove spinal AVMs:
Endovascular embolization. Endovascular embolization can lower the risk of bleeding and other complications of spinal AVMs.
A catheter is inserted into an artery in the leg. The catheter is then threaded to an artery in the spinal cord that feeds the AVM. Small particles of a gluelike substance are injected. This blocks the artery and reduces blood flow into the AVM. This procedure doesn't permanently destroy the AVM.
You may need endovascular embolization before other types of surgery. This can lower the risk of bleeding during surgery or shrink the AVM so that surgery is more successful.
Your healthcare team discusses with you the benefits and risks of surgery to remove the spinal AVM. Because the AVM is so close to the spinal cord, spinal AVM surgery is complex. See an experienced neurosurgeon for this type of surgery.
You may be referred to a doctor who specializes in disorders of the brain and nervous system, known as a neurologist.
In addition to asking the questions you've prepared, don't hesitate to ask other questions during your appointment.
You're likely to be asked several questions. Being ready to answer them can allow for more time to go over points you want to discuss in more detail. You may be asked: