Brain Aneurysms

Preventing Rupture and Bleeding

If you or a loved one has a brain aneurysm, then you may have questions about what this means and what to expect.

Aneurysms are weak areas in the wall of a blood vessel. A brain aneurysm is an aneurysm in a cerebral artery, which is the type of blood vessel that carries oxygen-rich blood to the brain.

Symptoms of Brain Aneurysms

Very often, small aneurysms do not cause any symptoms. Sometimes, however, a small brain aneurysm might push against nearby blood vessels or other structures in the brain as it grows.

A small or growing aneurysm can produce symptoms such as headaches, double vision, or pain around the eyes. Often, mild symptoms serve as a warning that prompts diagnosis, and effective treatment can be started before any serious symptoms occur.

Over time, the weak areas in the walls of arteries may balloon out, causing the blood vessel to become weaker as the aneurysm grows. Occasionally, aneurysms can leak or rupture, causing a hemorrhagic stroke, the type of stroke that is characterized by bleeding inside the brain.

Symptoms of a Ruptured or Bleeding Brain Aneurysm

If a brain aneurysm bleeds, the most common symptom is a "thunderclap headache" that many people describe as the “worst headache of their lives.” Severe neck pain and stiffness, stroke symptoms. collapse, loss of consciousness or seizures may also occur.

When a brain aneurysm ruptures, it causes hemorrhage (bleeding.) In these instances the region of the brain that normally receives blood supply from the bleeding artery may not receive enough blood flow, leading to an ischemic stroke as well as a hemorrhagic stroke.

Causes of Bleeding and Rupture of Aneurysms

Overall, there is a small risk of bleeding from a brain aneurysm. Aneurysms are more likely to bleed after they reach a size of more than 10 millimeters or about a third of an inch.

Aneurysms may bleed during situations when blood pressure is excessively elevated.

Episodes of markedly high blood pressure can be triggered by a number of causes, including:

  • The use of illicit drugs, such as cocaine and amphetamines
  • Major fluctuations in heart, kidney or liver function
  • Medical emergencies

Prevention of Brain Aneurysm Ruptures and Bleeds

There are a number of effective ways to prevent a brain aneurysm from bleeding. Some aneurysms can be repaired surgically or with a neuro-interventional procedure to reduce the risk of bleeding. Whether or not you are a candidate for a brain aneurysm repair depends on the location and size of your aneurysm, as well as your overall health and ability to safely tolerate a procedure.

Recovery After a Brain Aneurysm Ruptures and Bleeds

The prognosis after an aneurysm bleed is variable, depending on the size of the bleed. A brain aneurysm rupture can be treated, but approximately 10 percent of people with a ruptured aneurysm do not survive.

Up to 4 percent of brain aneurysm rupture survivors can bleed again within the first 24 hours after the initial episode of bleeding.

After a brain aneurysm bleeds, surgery may be needed to remove the blood. But, often the blood slowly dissolves on its own. Often, surgery is not necessary, depending on the amount of blood and the location of bleeding in the brain.

Why People Develop Brain Aneurysms

It is estimated that approximately two percent of the population in the United States has at least one aneurysm in the brain. This sounds like a very high number, but it is estimated that up to 80 percent of those who are living with a brain aneurysm will never experience bleeding in the brain.

Often, the tendency to develop aneurysms is inherited through heredity. There are also some factors that may increase the chances of developing an aneurysm, such as long-term hypertension (high blood pressure) and cigarette smoking.

Brain aneurysms are more likely to develop at locations in the blood vessels where arteries divide into branches. The following arteries in the brain are the most common locations of aneurysms:

  • The anterior communicating artery (35 percent)
  • The posterior communicating artery (25 percent)
  • The middle cerebral artery (22 percent)

A Word from Verywell

If you or your loved one has been diagnosed with a brain aneurysm, you should rest assured that there are effective ways to prevent it from bleeding.

If you or your loved one has experienced a brain aneurysm rupture, then you may be under a great deal of stress. However, you should know that brain aneurysms are not rare and that the medical and surgical care of brain aneurysms can improve your outcome significantly.

Many people recover from brain aneurysm rupture and continue to improve over time with close medical care and rehabilitation that is very similar to stroke rehabilitation.

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Article Sources
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