How Are AVMs Diagnosed?
To find out if a patient has a brain, spinal, or other AVM, the doctor will examine the patient and perform other tests to locate the AVM and evaluate its features. Pediatric neurosurgeons and other specialists have expertise in diagnosing and treating children with AVMs and blood flow disorders in the brain.
Tests to diagnose AVM may include:
- Medical history and physical examinations will be performed, during which the doctor will ask about symptoms and medical history.
- Catheter angiography uses X-ray imaging and an injection of contrast material to examine blood vessels in different areas of the body in order to diagnose certain conditions and diseases. X-ray imaging is used to provide detailed images of the blood vessels in the brain, spine, or other parts of the body. Images allow doctors to locate the AVM and learn about its structure.
- CT scan (computerized tomography scan) uses X-rays to create a detailed cross-sectional image of the brain, spine, or other areas of the body.
- MRI (magnetic resonance imaging) uses powerful magnets and radio waves to create detailed images of the brain, spine, or other part of the body where the AVM is located.
How Are AVMs Treated?
There are several ways to treat brain or spinal AVMs. The neurosurgeon will discuss available options for each patient depending on the location and size of the AVM, as well as the patient’s age and overall health. If appropriate, noninvasive or minimally invasive methods will be considered. Treatment options for AVMs include:
- Observation and medication may be appropriate in some cases, and some AVMs don’t need to be treated at all. The doctor may decide to observe the patient and watch for any changes. The patient may need to take anticonvulsant medication to prevent seizures or medication to lower blood pressure.
In children, an AVM grows as the child’s body grows, so monitoring AVM growth is especially important to prevent complications and relieve symptoms.
- Stereotactic radiosurgery uses targeted radiation to destroy the AVM without entering the skull. The radiation causes the blood vessels in the AVM to regress (go back to their previous state) slowly during the months or years after the treatment. This noninvasive therapy works best for small AVMs or an AVM that has not already caused considerable bleeding.
- Surgical resection (removal) is typically recommended for AVMs located in areas of the brain that are amenable to surgery: if there is no great risk of bleeding or seizures, and the AVM is in an area that can be reached easily. With resection, the AVM is immediately removed, eliminating the risk of future hemorrhage or bleeding. This surgery is performed under general anesthesia. A surgical opening is made in the skull and the brain is gently moved back so that the AVM can be located. After this surgery, most patients stay in the hospital for five to seven days, followed by short-term rehabilitation of two to three days.
- Endovascular embolization is a procedure that uses small particles to block a blood vessel and reduce the size of a brain AVM. It is less invasive than traditional surgery. This can very rarely be used alone to cure AVMs. Typically, it is used in combination with surgical resection or radiosurgery to make the AVM a better target for radiation or to help reduce the risks of the surgery. In some large brain AVMs, endovascular embolization may be used to reduce stroke-like symptoms by redirecting blood back to brain tissue. During this procedure, the surgeon injects an embolizing agent (a tiny particle or object, such as a medical balloon) into the brain through a catheter to block the artery and reduce blood flow into the AVM.
Clinical trials are research studies in which new treatments for AVMs, including drugs, diagnostic tests, procedures, and therapies, are tested in people to see if they are safe and effective. Research is always being conducted to improve the standard of medical care for people with AVMs.