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What you should know about brain aneurysms

April 04, 2019 | UCI Health
doctors examining patient brain scan for aneurysm

Brain aneurysms can lurk in the brain and present no symptoms — until one ruptures.

Aneurysms form in a weakened area of an artery in the brain, producing an abnormal bulge or balloon that can burst.

When one does, it may cause life-threatening brain hemorrhage that requires quick action to minimize the risk of disability or death.

Treat, or watch and wait?

An estimated six million people in the United States have an unruptured aneurysm but most don’t know it. Sometimes patients may become aware they have an aneurysm during imaging tests for other conditions, says UCI Health neurosurgeon Dr. Li-Mei Lin.

These patients are often told that the aneurysm can be safely monitored and does not need treatment.

Lin disagrees, since the average size of a ruptured aneurysm is 4.5 millimeters, which is considered small.

“Small aneurysms can be safely and successfully treated, preventing the potentially fatal effects from a rupture.”

Aneurysm treatment options

For decades, the only treatment options for an aneurysm were: 

  • Clipping: A small metal clip is placed at the neck of the aneurysm to stop blood flow to it.
  • Coiling: Is a minimally invasive endovascular treatment in which metal coils are placed in the bulge, causing a clot to form. Coiling has recurrence rates as high as 20 percent and there also is a high risk of rupture during the procedure.

The newest technique for treating an aneurysm is flow diversion. This approach involves placement of a stent to block blood flow to the aneurysm.

This causes a clot to form over time, while also providing a scaffold for new blood vessels to grow. This eventually seals the aneurysm off from the main artery, essentially curing it.

Who develops aneurysms?

Aneurysms most commonly occur in adults between the ages of 40 and 60, however they may occur at any age, Lin says. Women are more likely than men to be affected, according to the Brain Aneurysm Foundation.

Most unruptured aneurysms do not produce any symptoms despite the risk of rupture. Larger aneurysms may cause symptoms associated with pressure on surrounding brain or nerves such as seizures, abnormal eye movements or headaches.

Symptoms of a burst aneurysm

If you experience these symptoms, seek prompt medical attention:

  • Blurred or double vision
  • A drooping eyelid
  • A dilated pupil
  • Pain above and behind one eye
  • Weakness and/or numbness

When to see a doctor

Lin believes that any patient diagnosed with an aneurysm should be evaluated by an aneurysm specialist who is experienced in all types of treatment.

For the same reason you wouldn’t put a first baseman on the pitcher’s mound, she says, patients and providers should not expect a neurosurgeon or neurointerventionalist without specialized training to be able to offer the full range of treatment for an aneurysm.

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