Diagnosis

To diagnose an AVM, your doctor will review your symptoms and perform a physical examination.

He or she may listen for a sound called bruit. Bruit is a whooshing sound caused by very rapid blood flow through the arteries and veins of an AVM. It sounds like water rushing through a narrow pipe. Bruit may interfere with hearing or sleep or cause emotional distress.

Tests commonly used to help diagnose AVM include:

• Cerebral angiography. Also called arteriography, this test uses a special dye called a contrast agent injected into an artery. The dye highlights the structure of blood vessels to better show them on X-rays.
• Computerized tomography (CT). CT scans use X-rays to create images of the head, brain or spinal cord and can help show bleeding.
• Magnetic resonance imaging (MRI). An MRI uses powerful magnets and radio waves to show detailed images of the tissues. An MRI can pick up on small changes in these tissues.
• Magnetic resonance angiography (MRA). An MRA captures the pattern and the speed and distance of blood flow through the vascular abnormalities.