Brain Aneurysm

Most people with an unruptured brain aneurysm don’t know they have one. A healthcare provider may find one during an imaging test of your brain, such as an MRI or CT scan that you got for a different medical reason.

If you have symptoms of a brain aneurysm, such as a severe headache, call 911 or go to the emergency room. A healthcare provider will order tests to see if a brain aneurysm has ruptured. These tests may include:

• CT (computed tomography) scan: This is often the first imaging test a provider will order to see if blood has leaked into your brain. A CT scan uses X-rays and computers to produce images of a cross-section of your body. Providers may also use a CT angiogram (CTA), which produces more detailed images of blood flow in your brain’s arteries. CTA can show the size, location and shape of an unruptured or ruptured aneurysm.
• MRI (magnetic resonance imaging) scan: MRI uses a large magnet, radio waves and a computer to produce detailed images of your brain. Magnetic resonance angiography (MRA) produces detailed images of your brain’s arteries and can show the size, location and shape of an aneurysm.
• Cerebral angiography: This is a procedure in which a neurosurgeon or an interventional neuroradiologist inserts a catheter into a blood vessel in your groin or wrist. They thread it to your brain to take more accurate images of the arteries in your neck and brain. This imaging test can find blockages in arteries in your brain or neck. It also can identify weak spots in an artery, like an aneurysm. Providers use this test to determine the cause of bleeding in your brain and the exact location, size and shape of an aneurysm.
• Cerebrospinal fluid (CSF) analysis: This test measures the substances in the fluid that surrounds and protects your brain and spinal cord (cerebrospinal fluid). A provider collects a CSF sample by performing a spinal tap (lumbar puncture). The analysis can detect bleeding around your brain.