Neurosurgery and Brain Health Brain Aneurysm 101 By Neurosurgery, January 14, 2015 According to the National Institute of Neurological Disorders and Stroke, an estimated six million Americans have an unruptured brain aneurysm, or one in 50 people. Of those six million, nearly 30,000 suffer a ruptured brain aneurysm, which are fatal nearly 40 percent of the time. To put that into perspective, someone in the U.S. has a ruptured brain aneurysm every 18 minutes. So, you can clearly see the importance of understanding the causes, symptoms, and treatments of this serious condition. What Is a Brain Aneurysm? A brain aneurysm is a weak or thin area in the wall of an artery in the brain that balloons out and fills with blood. It often looks like a berry hanging from a stem. In rare cases, the aneurysm ruptures and releases blood into the brain, which is commonly known as a subarachnoid hemorrhage. Depending on the severity of the hemorrhage, moderate or severe brain damage can occur, and possibly even death. The most common location for aneurysms is in the circle of Willis, or a network of blood vessels at the base of the skull that supply the brain with blood. Brain Aneurysm Causes When looking at the main causes of brain aneurysms, there are certain factors that can be controlled, and others that can’t. For example, if you have a family history, you are more likely to have an aneurysm than those who do not. And if you’ve suffered an aneurysm once before, you have a greater risk of developing another. The following factors may increase your risk for developing a brain aneurysm, and if you have already been diagnosed with one, these may increase the risk of it rupturing. Race – African Americans are more likely than other races to have a ruptured aneurysm. High blood pressure – The risk of rupture is much greater in people who have high blood pressure. In fact, if you already have high blood pressure, heavy lifting or straining can cause pressure to rise even more, which can result in developing an aneurysm or rupture. Smoking – A study published in Science Daily found that smoking significantly increases risk of developing an aneurysm and aneurysm rupture in people with certain genes. Smoking also causes high blood pressure and can accelerate the weakening of artery walls in the brain. Drug use – The use of illicit drugs, such as cocaine and amphetamines, can significantly increase the risk of developing an aneurysm or rupture. Brain Aneurysm Symptoms Most small aneurysms cause no symptoms and do not rupture. However, if they grow large enough, they can press on structures of the brain and cause: Headaches Blurred vision Changes in speech Sensitivity to light Neck pain Symptoms of a ruptured brain aneurysm often come on suddenly and can include extremely severe headaches that are different from past headaches, nausea and vomiting, and loss of consciousness. Treatment for Brain Aneurysms Because a ruptured aneurysm is a medical emergency, treatment is required immediately. At UPMC, there are two common treatment options, each depending on the size, location, and severity of the ruptured aneurysm. Clip ligation surgery – During this procedure, the surgeon removes a small piece of skull to gain access to the aneurysm. Then, a metal clip is placed at the base of the aneurysm to control the bleeding and to decrease the risk of more bleeding. Aneurysm coiling surgery – Aneurysm coiling is a less invasive procedure and may be an option for people who are having unruptured aneurysms treated or are suffering minimal bleeding from a rupture. During the procedure, metal coils are placed in the aneurysm through a catheter that is inserted in the groin area. The coils block the vessel supplying blood to the area of the brain with the aneurysm. If you have been diagnosed with a brain aneurysm, continue to make regular visits with your doctor. He or she will monitor its size and determine if any treatment is required. If you would like to learn more or suspect you may have aneurysm, visit the UPMC Department of Neurosurgery online or call 1-877-986-9862 to make an appointment.