Brain Aneurysm
Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.
Source: MedlinePlus, National Library of Medicine. Read the original source
MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.
A brain aneurysm is an abnormal bulge or "ballooning" in the wall of an artery in the brain. They are sometimes called berry aneurysms because they are often the size of a small berry. Most brain aneurysms produce no symptoms until they become large, begin to leak blood, or burst.
If a brain aneurysm presses on nerves in your brain, it can cause signs and symptoms. These can include:
- A droopy eyelid
- Double vision or other changes in vision
- Pain above or behind the eye
- A dilated pupil
- Numbness or weakness on one side of the face or body
Treatment depends on the size and location of the aneurysm, whether it is infected, and whether it has burst. If a brain aneurysm bursts, symptoms can include a sudden, severe headache, nausea and vomiting, stiff neck, loss of consciousness, and signs of a stroke. Any of these symptoms requires immediate medical attention.
NIH: National Heart, Lung, and Blood Institute
Symptoms, tests and care options
Further reading selected by MedlinePlus. Links open the original organizations’ websites.
- Brain Aneurysm: Treatment Options · Brain Aneurysm Foundation
- Brain Aneurysm: Warning Signs and Symptoms · Brain Aneurysm Foundation
- Catheter Angiography · Radiological Society of North America
- Cerebrospinal Fluid (CSF) Analysis · National Library of Medicine
- CT Angiography (CTA) · Radiological Society of North America
- Embolization of Brain Aneurysms and Arteriovenous Malformations/Fistulas · Radiological Society of North America
- Intracranial Vascular Treatments · Radiological Society of North America
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For a life-threatening emergency, call 911 in the U.S. or your local emergency number.
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