Arteriovenous Malformation

Diagnosis

Mayo Clinic doctors with training in brain conditions (neurologists), brain surgeons (neurosurgeons), specialists with training in brain imaging (neuroradiologists) and other specialists work together to diagnose an arteriovenous malformation (AVM). Specialists evaluate hundreds of people with arteriovenous malformation each year.

Your doctor will perform a comprehensive evaluation to diagnose an arteriovenous malformation. Your doctor may order several tests to rule out other neurological conditions. Radiologists who specialize in imaging the brain and nervous system conduct imaging tests. In Mayo Clinic's system, doctors usually receive test results within 24 hours.

Tests used to diagnose arteriovenous malformation include:

• Cerebral arteriography (cerebral angiography). In cerebral arteriography (cerebral angiography), a doctor inserts a long thin tube (catheter) into an artery in the groin and threads it to your brain using X-ray imaging. A doctor injects dye into the blood vessels of your brain to make them visible under X-ray imaging. Your doctor uses this test to determine the location and characteristics of the blood vessels feeding and draining the AVM.
• Computed tomography (CT) scan. A CT scan uses a series of X-rays to create a detailed, three-dimensional image of your brain. Sometimes a doctor may inject a dye into a vein to view the blood vessels in greater detail (CT angiogram).
• Magnetic resonance imaging (MRI). An MRI uses powerful magnets and radio waves to create detailed images of your brain. Sometimes a doctor may inject a dye into a blood vessel to view your blood vessels and show the blood circulation in your brain (magnetic resonance angiogram). An MRI shows the exact location of the arteriovenous malformation, which helps your doctor assess your risk and determine your treatment.

Read more about CT scan and MRI at MayoClinic.com.