Brain aneurysms can occur when areas of weakened arteries balloon under pressure. Arteries, which carry oxygen-rich blood and nutrients throughout the body, are structured to withstand the pressure caused by normal blood flow. However, they can become damaged as a result of high blood pressure (hypertension), the condition when the force of blood pushing against an artery’s interior wall is consistently too high.
Usually located along major arteries, aneurysms vary in shape and size, sometimes grow over time, and can rupture. Unruptured aneurysms can be problematic because they are susceptible to blood clots forming at the site of the weakened arterial wall. Clot, a mass of thickened blood, can affect the rate of blood flow through a vessel or block it entirely. Also, if a piece of clot breaks off, it can travel through the bloodstream, get stuck in another vessel, and block blood flow at that point. Larger aneurysms can press on nerves or push against the brain.
The sudden rupture of an aneurysm, known as hemorrhagic stroke, leaks blood directly into the brain or into the space between the brain and the skull.
IMPORTANT NOTE: This overview is provided for informational purposes only and should not be used as a substitute for talking with your doctor. Be sure to talk with your doctor for a complete discussion of this condition as well as the benefits and risks of any treatment options.