A potentially fatal brain abnormality, cerebral aneurysms occur when arteries in the skull become swollen, thin-walled, and dangerously enlarged. These bloated vessels may then rupture or leak, spilling blood into the brain. About 27,000 cases of ruptured cerebral aneurysms are reported each year in the United States, usually in people between the ages of 30 and 60.

Cerebral aneurysms can be caused by infections, tumors, trauma to the head, or unhealthy arteries due to plaque buildup or high blood pressure. In some people, cerebral aneurysms form during fetal development and persist throughout life. They are most often found near the bottom of the skull. Aneurysms are common; millions of people have them, and most never burst.

However, when an aneurysm does burst, the bleeding into the brain may cause a stroke, nerve damage, or death. People who survive an aneurysm will have long-term health problems such as swelling in the brain or the blockage of important arteries. For people who experience a burst aneurysm, it may feel like “the worst headache of my life.” High blood pressure, cigarette smoking, heavy alcohol use, and drug abuse (particularly the use of cocaine) increase a person’s risk of the rupture of a cerebral aneurysm.

Even aneurysms that do not burst, though, may cause serious problems in some people. An enlarged vessel can bulge out against surrounding brain material, potentially causing eye pain, facial paralysis, and vision problems.

Aneurysms can be detected with a CT scan or MRI, and treatment options vary depending on their size and location. If the aneurysm is small and located in a low-risk area of the brain, doctors may simply leave it there.

ADDITIONAL FACTS

  1. A small number of patients will experience sentinel, or warning, headaches when an aneurysm leaks for days or weeks before rupturing.
  2. Doctors use CT scans, MRIs or angiography (x-rays of blood vessels after injecting dye) to pinpoint the site of an aneurysm, usually after symptoms have already occurred.
  3. A physician may perform surgery to repair damaged arteries, although it can be risky.
  4. To treat the problem without surgery, a doctor may inject a substance via a thin tube threaded through the blood vessels to close off the aneurysm. It’s estimated that 40 percent of patients whose aneurysms burst do not survive the first 24 hours, and up to another 25 percent die within 6 months. Those whose aneurysms are treated before they rupture generally have a better prognosis; they recover faster and require less rehabilitative therapy.