What is a brain aneurysm?

A brain aneurysm is a weakened area of a blood vessel in the brain that bulges outward. Typically, the vessels that are likely to weaken are in the base of the brain at junctions where the vessels fork.

In most cases, a brain aneurysm will not cause any issues. In rare instances, the aneurysm will burst and cause a hemorrhagic stroke. If this occurs, immediate treatment is necessary to stop the bleeding into the brain.

Although approximately 6 million Americans have an unruptured brain aneurysm, only 30,000 suffer a rupture each year. Sixty percent of patients with ruptures will survive.

Common related conditions
Hemorrhagic Stroke Stroke

Causes of brain aneurysms

The exact cause of a brain aneurysm is unknown, but some patients may be born with a blood vessel defect that could lead to a brain aneurysm.

Risk factors for brain aneurysms

There are several factors that can increase your chance of developing a brain aneurysm including:

  • Age — brain aneurysms are more common as you age
  • Gender — women are more likely to suffer from a brain aneurysm
  • Smoking — smokers are more likely to suffer a brain aneurysm
  • Hypertension (high blood pressure)
  • Use of illicit drugs such as cocaine
  • Excessive alcohol consumption
  • Head injury or trauma
  • Family members who have suffered brain aneurysms
  • Blood vessel abnormalities in the brain at birth

Symptoms of a brain aneurysm

Symptoms of a brain aneurysm that has not ruptured include:

  • Dilated pupil
  • Vision problems
  • Face numbness on one side
  • Pain behind one of your eyes
  • Difficulty speaking

If you are having any of these symptoms, see your doctor right away for treatment.

Symptoms of a ruptured aneurysm include:

  • Severe headache
  • Stiff neck
  • Nausea and vomiting
  • Eyelids that are drooping
  • Seizure

If you or a loved one has a sudden, severe headache, seizures or lose consciousness, call 911 immediately.

Diagnosis of a brain aneurysm

If you present with a sudden, severe headache at the emergency room, the doctors will quickly perform diagnostic testing to determine if you have a ruptured brain aneurysm. Testing may include:

CT scan (computed tomography) or MRI (magnetic resonance imaging)

CT and MRI scans can detect brain aneurysms that are larger than 3 - 5 millimeters. Both diagnostic tests take detailed images of the brain and vessels to determine the location and severity of the aneurysm. In many cases, a contrast dye is injected into a vessel in order to quickly locate the aneurysm.

Cerebral angiogram

An angiogram is a very reliable test to diagnose a brain aneurysm. During this procedure, a catheter is thread into a vein in the leg, up to the brain. When the catheter is in the correct location, a contrast dye will be injected into a vessel to locate the aneurysm.

Lumbar puncture or cerebrospinal fluid test

A cerebrospinal fluid test can detect blood in the spinal fluid. During this procedure, spinal fluid is removed from the areas surrounding the brain and evaluated for the presence of blood cells. If there are blood cells in the fluid, you could have a leaking or ruptured aneurysm.

Treatment for brain aneurysms

Immediate treatment is important to survive a ruptured brain aneurysm. The goal of early treatment is to stop the blood flow from the vessel. Your doctor will decide what procedure will have the best results for your case. Surgical treatments for brain aneurysms include:

Surgical clipping

During a surgical clipping procedure, a neurosurgeon carefully removes a piece of your skull, locates the bleeding aneurysm and clips it to stop the bleeding. Once the bleeding stops, he will close the skull.

Endovascular embolization (coiling)

Endovascular embolization or coiling is a less invasive treatment option where a catheter is thread up to the brain from an incision in the leg. Tiny coils are pushed up into the bleeding aneurysm and block the vessel to stop the bleeding. Although this procedure potentially has fewer side effects, it may need to be repeated.

If you have a brain aneurysm that hasn’t ruptured, lifestyle changes and medication for heart disease may be appropriate to prevent a rupture. Some lifestyle changes include quitting smoking, taking blood pressure medicines to control your blood pressure, eating a healthy diet and exercising.

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