A subarachnoid hemorrhage (SAH) is a type of brain hemorrhage that often occurs between the brain and the membrane that protects it. A SAH is a medical emergency.
If you suspect you have a subarachnoid hemorrhage, call 911 immediately or get to your nearest emergency department.
The brain has three layers of protective membranes called meninges. The outermost layer is the dura mater, the middle layer is the arachnoid, and the layer closest to the brain is the pia mater. A subarachnoid hemorrhage occurs when bleeding happens in the space below the arachnoid layer.
Most often, the hallmark symptom of a subarachnoid hemorrhage is experiencing what feels like the worst headache you've ever had. Other symptoms may include:
Recognizing the symptoms of a subarachnoid hemorrhage and getting a prompt diagnosis and treatment is vital to improving recovery outcomes.
To diagnose a subarachnoid hemorrhage, your doctor will first ask about your symptoms and review your medical history.
Your doctor will work to locate the source of the bleeding by using imaging testing such as a CT scan or an MRI. They may also order one of the following advanced diagnostic tests for a subarachnoid hemorrhage:
Once diagnosed, the goal is to stop the bleeding, prevent further complications and promote healing. Your treatment plan might involve:
The most common risk factor of a subarachnoid hemorrhage is a brain aneurysm, which is a balloon in your blood vessel that eventually bursts.
Other underlying risk factors of a subarachnoid hemorrhage include:
In some cases, there may not be an underlying cause of a subarachnoid hemorrhage.
The prognosis for subarachnoid hemorrhage depends on the severity of the bleeding and the timing of your treatment. Some people recover fully with no long-term effects, while others may experience permanent brain damage.
Your doctor may recommend:
While predicting a subarachnoid hemorrhage can be tricky, taking preventive measures can help prevent them. These include:
Most strokes are preventable and many of the risk factors are controllable. Our stroke risk quiz helps you estimate your chance of experiencing a stroke, find ways to minimize your risk and get an idea of what to do next based on your results.
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