A brain aneurysm occurs when a weak spot in your brain’s arterial
wall bulges and fills with blood. It may also be called an intracranial (skull)
aneurysm or a cerebral (brain) aneurysm. A brain aneurysm is a potentially
life-threatening condition that can affect a person at any age. If a brain
aneurysm bursts, it’s an emergency situation that can result in a stroke, brain
damage, and even death if not treated immediately.
What Does a Brain Aneurysm Look Like? What Causes It?
Brain aneurysms can take several forms. Almost 90
percent are saccular aneurysms.
This type forms a sac outside the artery that looks like a berry (another name
for it is a “berry aneurysm”). A fusiform
aneurysm is an uncommon aneurysm that causes the artery to bulge
all the way around. A dissecting
aneurysm is a tear in one of the several linings of an artery. It can
leak blood into the other layers and balloon out or block the artery.
Some events encourage the development of an aneurysm in the
brain. Some aneurysms develop over the course of a person’s lifetime, some are
inherited, and some are a result of brain injuries.
polycystic kidney disease (ADPKD) is an inherited condition that
affects kidney function and also produces cobweb-like, fluid-filled pockets
(cysts) in brain tissue. The condition raises blood pressure, which weakens
blood vessels in the brain and elsewhere in the body.
Marfan’s syndrome is
also an inherited condition and affects the genes that control the formation of
the body’s connective tissue. Damage to the structure of the arteries creates
weaknesses that can lead to brain aneurysms.
A traumatic brain injury can tear the tissue and create what’s
known as a dissecting aneurysm. A serious infection in the body can lead to an
aneurysm if the infection damages the arteries. Smoking and chronic high blood
pressure are also sources of many brain aneurysms.
Who’s at Risk for a Brain Aneurysm?
Brain aneurysms can affect anyone, but people with
atherosclerosis (hardening of the arteries) are at high risk of forming brain
aneurysms. Women over the age of 40 are at an increased risk as well. Other
people at risk for brain aneurysms are those who:
- abuse drugs
- have high blood pressure
- have congenital problems that affect the
- have had abnormal growths in the head or body
- have brain injuries
- have had severe infections of the blood or brain
- have high LDL cholesterol
- have a family history of aneurysms
What Are the Symptoms of a Brain Aneurysm?
Aneurysms are unpredictable and may not show any symptoms until
they rupture. Large or ruptured aneurysms will usually show definite symptoms
and require emergency medical care.
The following are symptoms and warning signs of an aneurysm or a ruptured
- headache or pain behind or above the eye (can be
mild or severe)
- dilated pupils
- drooping eyelids
- sensitivity to light
- blurred or double vision
- weakness or numbness on one or both sides of the
- trouble speaking or a change in awareness and
- trouble walking or dizziness
- nausea or vomiting
- seizure (convulsion)
- loss of consciousness
How Is a Brain Aneurysm Diagnosed?
Unless an aneurysm ruptures, it may be difficult to diagnose the
condition. There are tests that can help doctors locate aneurysms in people who
have family histories of the condition, high-risk factors, and inherited,
aneurysm-related health issues.
Computerized tomography (CT) and magnetic resonance imaging
(MRI) scans take pictures of the brain tissues and arteries. CT scans are
usually better at revealing any cranial bleeding that may already be present.
A spinal tap, where a
doctor draws fluid from the spine, can check for signs of bleeding in the
brain. Cerebral angiograms can
also check for bleeding and any abnormalities in the brain arteries.
Treating Brain Aneurysms
Treatments for aneurysms are usually based on the size, location,
and severity of the condition. Pain medication can soothe headaches and eye
pain. Your doctor can also prescribe medication designed to prevent blockage of
the blood vessels or relieve cranial pressure. If the aneurysm is accessible,
surgery can repair or cut off blood flow to the aneurysm. This can help prevent
further growth or a rupture.
What Is the Outlook for Someone With a Brain Aneurysm?
It’s important to be vigilant in monitoring an aneurysm for signs
of a rupture. People who get immediate
treatment for ruptures have much higher survival and recovery rates than those
who don’t seek emergency medical care right away. Be alert to the warning signs,
and if you have any of the risk factors, see your doctor immediately for an
That said, not all aneurysms will rupture. According to the Brain Aneurysm Foundation in Boston,
an estimated 50 to 80 percent of all aneurysms never rupture in a person's