A brain (cerebral) aneurysm is a bulging, weak area in the wall of an artery that supplies blood to the brain. In most cases, a brain aneurysm causes no symptoms and goes unnoticed. In rare cases, the brain aneurysm ruptures, releasing blood around the base of the brain and causing a type of stroke called a subarachnoid hemorrhage. Patients experience a severe headache known as a “thunderclap headache.” Urgent medical evaluation is necessary after aneurysms become symptomatic.
A person may inherit the tendency to form aneurysms, or aneurysms may develop because of hardening of the arteries (atherosclerosis) and aging. Some risk factors that can lead to brain aneurysms can be controlled, others cannot. The following risk factors may increase your risk for an aneurysm or, if you already have an aneurysm, may increase your risk of it rupturing:
Symptoms of a ruptured brain aneurysm often come on suddenly. If you have any of the following symptoms or notice them in someone you know, call 911 or other emergency services right away:
If you have non-emergency questions about brain aneurysms, call the Virginia Mason Neuroscience Institute at (206) 341-0420.