What causes a brain aneurysm to rupture?
If the expansion of the aneurysm reaches a point where the wall becomes too thin, the aneurysm will rupture and bleed into the space around the brain. This event is called a subarachnoid hemorrhage (SAH). This catastrophic event requires immediate and urgent medical attention.
After the first hemorrhage, about 46% of patients die. If the aneurysm is not repaired in time and a second hemorrhage occurs, about 80% of patients die.
Symptoms and causes of a brain aneurysm
Brain aneurysms may be asymptomatic (no symptoms) or rarely symptomatic (with symptoms). Symptoms associated with brain aneurysms depend on the location of the aneurysm in the brain.
Although a cerebral aneurysm may be present without symptoms, the most common initial symptom of a cerebral aneurysm is a subarachnoid hemorrhage (SAH). SAH is bleeding into the subarachnoid space (the space between the brain and the membranes that cover the brain). A ruptured cerebral aneurysm is the most common cause of SAH. SAH is a medical emergency and may be the cause of a hemorrhagic (bleeding) stroke.
Learn about unruptured brain aneurysms.
Treatment for ruptured aneurysms
At Johns Hopkins, we treat brain aneurysms using one of two methods, or a combination of methods, depending on the type of aneurysm and the individual patient, and may include:
- Microsurgical clipping for brain aneurysms
- Endovascular coiling for brain aneurysms
- Artery occlusion and bypass