Brain Aneurysm: Causes, Symptoms, and Treatment
Medically reviewed by Achuta Uppu, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Brain Aneurysm?
A neurologist, a doctor who treats brain and nerve problems, and a neurosurgeon, a surgeon who operates on the brain, care for people with brain aneurysms. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is a brain aneurysm?
A brain aneurysm is a weak spot on an artery in the brain that balloons out and fills with blood. The most common type looks like a small berry on a stem, so it is often called a berry aneurysm. Aneurysms can also be fusiform, meaning the whole artery bulges out on all sides, or mycotic, meaning an infection weakened the artery wall. About 1 in 50 people has one, but only a small number cause symptoms or burst.
Symptoms
Most aneurysms cause no symptoms until they grow large, leak, or burst. A large, growing aneurysm can press on brain tissue and nerves and cause:
- Pain above or behind the eye.
- A droopy eyelid or a widened (dilated) pupil.
- Double vision or other vision changes.
- Numbness or weakness on one side of the face or body.
A leak or rupture causes a sudden, severe headache. People often call it the worst headache of their life. A small leak, called a sentinel bleed, can cause a warning headache days or weeks before a major rupture. Other rupture symptoms include nausea, vomiting, a stiff neck, sensitivity to light, seizures, or loss of consciousness.
Causes and who gets it
Aneurysms form where an artery wall is weak. Some are present from birth. Risk factors include:
- Being female. Aneurysms are more common in women than in men.
- Age. They are most common in adults between ages 30 and 60.
- Family history of brain aneurysms.
- High blood pressure, which damages and weakens arteries.
- Cigarette smoking, which is linked to aneurysm formation and rupture.
- Drug use, especially cocaine or amphetamines.
- Polycystic kidney disease, a condition that causes fluid-filled sacs in the kidneys.
- Connective tissue disorders such as Ehlers-Danlos syndrome, which weaken artery walls.
- Hardening of the arteries, head trauma, and infection (a mycotic aneurysm).
How doctors diagnose it
Most aneurysms are found by accident on scans done for other reasons. If a rupture is suspected, a CT scan of the head is often the first test. It looks for blood around the brain. Other tests include:
- CT angiography (CTA) or MR angiography (MRA), scans that use dye or magnets to show the aneurysm's size, location, and shape.
- Cerebral angiography, in which a doctor passes a thin tube from the groin up to the brain arteries and injects dye. It shows the exact location, size, and shape.
- A spinal tap, which checks the fluid around the brain and spine for blood.
Treatment
Not every aneurysm needs treatment. Very small ones that are not growing are often watched with regular imaging. Your doctor will weigh the risk of rupture against the risks of treatment, considering your age, health, and family history.
When treatment is needed, the two main options are:
- Microvascular clipping. Open brain surgery in which the surgeon places a tiny metal clip across the aneurysm's neck to stop blood flow into it. Aneurysms that are completely clipped generally do not come back.
- Endovascular treatments, which are usually easier on the body. A doctor threads a catheter from an artery in the groin up to the brain. Tiny platinum coils can be placed in the aneurysm to block blood flow, or a small stent can divert blood away from it.
Treating high blood pressure and quitting smoking may lower the chance that an aneurysm ruptures. People known to have an aneurysm need regular visits to make sure it is not changing size or shape.
When to see a doctor
If you have a sudden, severe headache, especially with nausea, vomiting, a stiff neck, seizure, or fainting, call 911 right away. Also call 911 for sudden weakness or numbness, trouble speaking, or a sudden change in vision. A ruptured aneurysm is a medical emergency. Also call if you have a headache that is unusual for you or your worst headache ever.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. This kind of doctor can check your blood pressure, help you quit smoking, and refer you to a neurologist when needed. They can also arrange follow-up imaging and coordinate your care over time.
Common questions
Can a brain aneurysm be prevented?
There is no known way to prevent a berry aneurysm from forming. But treating high blood pressure and quitting smoking may reduce the chance that an existing aneurysm ruptures.
How common are brain aneurysms?
One in 50 people has a brain aneurysm. Only a small number of these cause symptoms or rupture.
What is a sentinel headache?
It is a warning headache caused by a small leak from an aneurysm. It can happen days or weeks before a major rupture. Only a small number of people get one before a rupture.
What is recovery like after a rupture?
Outcomes vary. Some survivors have no permanent disability, while others have moderate to severe disability. Recovery may include physical, speech, and occupational therapy to improve function.
Sources
- National Institute of Neurological Disorders and Stroke - Cerebral Aneurysms
- MedlinePlus - Aneurysm in the Brain
- MedlinePlus - Brain Aneurysm
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
