How MRI Helps Detect and Evaluate a Brain Aneurysm

At Independent Physicians Medical Center (IPMC) in Northeast Philadelphia, we offer advanced MRI imaging, including specialized scans that help detect aneurysms safely and effectively—without the stress of hospital wait times.

What Is a Brain Aneurysm?

A brain aneurysm occurs when a weak area of a cerebral artery wall bulges outward due to pressure from blood flow. Most aneurysms are unruptured and may not cause symptoms, but larger or growing aneurysms carry a higher risk of rupture, which can lead to bleeding in the brain and stroke-like emergencies.

How Can MRI Detect a Brain Aneurysm?

MRI Basics

MRI (Magnetic Resonance Imaging) uses powerful magnets and radio waves to produce highly detailed images of the brain and soft tissues without using radiation. MRI can help doctors:

• Visualize the shape and size of an aneurysm
• Determine its exact location in brain arteries
• Monitor aneurysms over time for changes or growth

MRI With Contrast and Angiography

In many cases, doctors use a special MRI technique called magnetic resonance angiography (MRA). This scan may include a contrast dye injected into a vein to highlight blood vessels in the brain, making it easier to see aneurysms and assess their characteristics.

Unlike traditional MRI, MRA focuses specifically on blood vessels, providing clearer images of arteries that could be affected by aneurysms.

MRI vs. Other Imaging Tests

MRI and MRA are excellent for detecting unruptured brain aneurysms because they provide detailed images of blood vessel structure without radiation. However:

• CT scans (especially CT angiography) are commonly used when a ruptured aneurysm is suspected, particularly in emergency settings.
• Cerebral angiography is a more invasive imaging test that provides very detailed views of blood vessels and is often used when other tests are inconclusive.

Your physician will choose the best imaging based on your symptoms, medical history, and risk factors.

Who Needs an MRI for Aneurysm Evaluation?

MRI or MRA may be recommended if you:

• Have risk factors such as a family history of aneurysms
• Experience symptoms like sudden severe headache, vision changes, or facial numbness
• Need follow-up monitoring of a known unruptured aneurysm

Many people with unruptured aneurysms may have no symptoms at all, and these are sometimes discovered incidentally during brain imaging for other reasons.

Why Early Detection Matters

Detecting an aneurysm before it ruptures can be life-saving. Smaller aneurysms may be monitored regularly to watch for growth, while larger or high-risk aneurysms may require preventive treatment, such as surgical clipping or endovascular procedures.