Brain Aneurysm
Condition
(Cerebral Aneurysm; Intracranial Aneurysm; Intracerebral Aneurysm; Aneurysm, Brain; Aneurysm, Cerebral; Aneurysm, Intracranial; Aneurysm, Intracerebral)
Definition
A brain aneurysm is a bulge in a blood vessel in the brain. The bulge is filled with blood. It can put pressure on parts of the brain. The blood vessel can also burst and cause bleeding in the brain. Finding an aneurysm early can help prevent severe or fatal problems in some people.
An aneurysm is a weakened blood vessel in the brain that collects blood. The bulging, blood-filled pocket can put pressure on parts of the brain, pressing on nearby nerves. This can cause symptoms or cause the blood vessel to rupture (hemorrhage).
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Causes
Brain aneurysms are caused by a weakness in the wall of a brain artery. This may be due to aging, genes, and certain conditions.
Risk Factors
Brain aneurysms are more common in older adults and women. Other things that raise the risk are:
- Certain inherited diseases
- A family history of aneurysms
- Plaque build-up or infection in artery walls
- Smoking, heavy alcohol use, or drug abuse
- High blood pressure
- Tumors
- Traumatic head injury
- Arteriovenous malformations
Symptoms
Symptoms may include:
- Pain behind the eye
- Numbness
- Weakness
- Changes in eyesight
- Drooping eyelid
- A large pupil (black area) in the eye
- Problems speaking
A leaking or burst aneurysm may cause:
- Headache
- Nausea and vomiting
- Stiff neck
- Confusion or sleepiness
- Loss of consciousness
- Seizures
Diagnosis
The doctor will ask about symptoms and past health. A physical exam will be done. Tests may include:
Treatment
Treatment depends on the type, size, and site of the aneurysm. It also depends on the person's health.
If the aneurysm is not leaking or burst, options may be:
- Watching for symptoms, leaking, and changes in the size of the aneurysm
- Medicines to treat:
- Any underlying conditions—and those that raise the risk of a burst
- Symptoms of the aneurysm
Procedures may be done to prevent or treat a burst aneurysm. They include:
- Endovascular procedures to block blood flow to the aneurysm, such as:
- Embolization—Uses a threaded tube to place coils in the aneurysm
- Flow diversion—Uses a threaded tube to place a stent outside the aneurysm
- Microvascular clipping—Brain surgery to clip and cut off blood flow to the aneurysm
Therapy can help with physical function, speech, and coping for people who had a burst aneurysm.
Prevention
A brain aneurysm cannot always be prevented. To help reduce the risk:
- Control high blood pressure.
- Do not smoke or drink too much alcohol.
- Do not use illegal drugs.
Brain Aneurysm Foundation
National Institute of Neurological Disorders and Stroke
CANADIAN RESOURCES:
Brain Injury Canada
Heart and Stroke Foundation of Canada
Brain Aneurysm Foundation
National Institute of Neurological Disorders and Stroke
CANADIAN RESOURCES:
Brain Injury Canada
Heart and Stroke Foundation of Canada
References
- Cerebral aneurysm. American Association of Neurological Surgeons website. Available at: https://www.aans.org/Patients/Neurosurgical-Conditions-and-Treatments/Cerebral-Aneurysm.
- Cerebral aneurysms fact sheet. National Institute of Neurological Disorders and Stroke website. Available at: https://www.ninds.nih.gov/cerebral-aneurysms-fact-sheet.
- Flow diversion for aneurysms with stents. Johns Hopkins Medicine website. Available at: https://www.hopkinsmedicine.org/neurology_neurosurgery/centers_clinics/aneurysm/treatment/flow-diversion.html.
- Hu, S., Yu, N., et al. A meta-analysis of risk factors for the formation of de novo intracranial aneurysms. Neurosurgery. 2019; 85 (4): 454-465.
- Subarachnoid hemorrhage. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/subarachnoid-hemorrhage.
Contributors
- Nicole Meregian, PA
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