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A brain (cerebral) aneurysm is a bulging, weak
area in the wall of an artery that supplies blood to the brain. In most cases,
a brain aneurysm causes no symptoms and goes unnoticed. In rare cases, the
brain aneurysm ruptures, releasing blood into the skull and causing a
When a brain aneurysm ruptures,
the result is called a
subarachnoid hemorrhage. Depending on the severity of
the hemorrhage, brain damage or death may result.
The most common
location for brain aneurysms is in the network of blood vessels at the base of
the brain called the circle of Willis.
A person may inherit the tendency
to form aneurysms, or aneurysms may develop because of hardening of the
arteries (atherosclerosis) and aging. Some risk factors that can
lead to brain aneurysms can be controlled, and others can't. The following risk
factors may increase your risk for an aneurysm or, if you already
have an aneurysm, may increase your risk of it rupturing:
Most brain aneurysms cause no symptoms and may only be discovered during
tests for another, usually unrelated, condition. In other cases, an unruptured
aneurysm will cause problems by pressing on areas in the brain. When this
happens, the person may suffer from severe headaches, blurred vision, changes
in speech, and neck pain, depending on what areas of the brain are affected
and how bad the aneurysm is.
Symptoms of a ruptured brain aneurysm often
come on suddenly. If you have any of the following symptoms or
notice them in someone you know, call 911 or other emergency services right away:
Because unruptured brain aneurysms often do not
cause any symptoms, many are discovered in people who are being treated for a
If your doctor believes that you
have a brain aneurysm, you may have the following tests:
Your doctor will think about several things before
deciding the best treatment for you. Things that will determine the type of
treatment you receive include your age, size of the aneurysm, any additional
risk factors, and your overall health.
Because the risk of a
small (less than 10 mm) aneurysm rupturing is low and surgery for a brain
aneurysm is often risky, your doctor may want to continue to
observe your condition rather than do surgery. If your aneurysm
is large or causing pain or other symptoms, though, or if you have had a previous
ruptured aneurysm, your doctor may recommend surgery.
The following surgeries are used to treat both ruptured and unruptured
Some aneurysms bulge in such a way that the aneurysm has to
be cut out and the ends of the blood vessel stitched together, but this is very
rare. Sometimes the artery is not long enough to stitch together, and a
piece of another artery has to be used.
Aneurysms that have bled
are very serious. In many cases, they lead to death or disability. Management
includes hospitalization, intensive care to relieve pressure in the brain
and maintain breathing and vital functions (such as blood pressure), and
treatment to prevent rebleeding.
Other Works Consulted
Connolly ES Jr, et al. (2012). Guidelines for the management of aneurysmal subarachnoid hemorrhage: A guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke. Published online May 3, 2012 (doi: 10.1161/STR.0b013e3182587839). Also available online: http://stroke.ahajournals.org/content/early/2012/05/03/STR.0b013e3182587839.full.pdf+html.
Ropper AH, Samuels MA (2009). Cerebrovascular diseases. In Adams and Victor's Principles of Neurology, 9th ed., pp. 746–845. New York: McGraw-Hill.
ByHealthwise StaffPrimary Medical ReviewerE. Gregory Thompson, MD - Internal MedicineSpecialist Medical ReviewerKarin M. Lindholm, DO - Neurology
Current as ofAugust 21, 2015
Current as of:
August 21, 2015
E. Gregory Thompson, MD - Internal Medicine & Karin M. Lindholm, DO - Neurology
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