Cerebral Aneurysm

Definition

Definition of Cerebral Aneurysm
A cerebral or brain aneurysm is a cerebrovascular disorder in which weakness in the wall of a cerebral artery or vein causes a localized dilation or ballooning of the blood vessel.

Symptoms

Symptoms of Cerebral Aneurysm
A small, unchanging aneurysm will produce little, if any, symptoms. Before a larger aneurysm ruptures, the individual may experience such symptoms as a sudden and unusually severe headache, nausea, vision impairment, vomiting, and loss of consciousness, or the individual may be asymptomatic, experiencing no symptoms at all.

If an aneurysm ruptures, it leaks blood into the space around the brain. This is called a “subarachnoid hemorrhage.” Depending on the amount of blood, it can produce:

1. a sudden severe headache that can last from several hours to days
2. nausea and vomiting
3. drowsiness and/or coma

Causes

Causes of Cerebral Aneurysm
Aneurysms may result from congenital defects, preexisting conditions such as high blood pressure and atherosclerosis (the buildup of fatty deposits in the arteries), or head trauma. Cerebral aneurysms occur more commonly in adults than in children but they may occur at any age. They are more common in women than in men, by a ratio of 3 to 2.

Diagnosis

Diagnosis of Cerebral Aneurysm
Diagnostic tests include:

1. Computerized tomography (CT): A CT scan, a specialized X-ray exam, is usually the first test used to determine if you have bleeding in the brain. The test produces images that are 2-D "slices" of the brain. With this test, you may also receive an injection of a dye that makes it easier to observe blood flow in the brain and may indicate the site of a ruptured aneurysm. This variation of the test is called CT angiography.
2. Cerebrospinal fluid test: If you've had a subarachnoid hemorrhage, there will mostly likely be red blood cells in the fluid surrounding your brain and spine (cerebrospinal fluid). Your doctor will order a test of the cerebrospinal fluid if you have symptoms of a ruptured aneurysm, but a CT scan hasn't shown evidence of bleeding. The procedure to draw cerebrospinal fluid from your back with a needle is called a lumbar puncture or spinal tap.
3. Magnetic resonance imaging (MRI): An MRI uses a magnetic field and radio waves to create detailed images of the brain, either 2-D slices or 3-D images. The use of a dye (MRI angiography) can enhance images of blood vessels and the site of a ruptured aneurysm. This imaging test may provide a clearer picture than a CT scan.
4. Cerebral angiogram: During this procedure, also called a cerebral arteriogram, your doctor inserts a thin, flexible tube (catheter) into a large artery - usually in your groin - and threads it past your heart to the arteries in your brain. A special dye injected into the catheter travels to arteries throughout your brain. A series of X-ray images can then reveal details about the conditions of your arteries and the site of a ruptured aneurysm. This test is more invasive than others and is usually used when other diagnostic tests don't provide enough information.

Treatment

Treatment of Cerebral Aneurysm
Emergency treatment for individuals with a ruptured cerebral aneurysm generally includes restoring deteriorating respiration and reducing intracranial pressure. Currently there are two treatment options for securing intracranial aneurysms: Surgical clipping or endovascular coiling. If possible, either surgical clipping or endovascular coiling is usually performed within the first 24 hours after bleeding to occlude the ruptured aneurysm and reduce the risk of rebleeding.

Prognosis

Prognosis of Cerebral Aneurysm
The prognosis for a patient with a ruptured cerebral aneurysm depends on the extent and location of the aneurysm, the person's age, general health, and neurological condition. Some individuals with a ruptured cerebral aneurysm die from the initial bleeding. Other individuals with cerebral aneurysm recover with little or no neurological deficit. The most significant factors in determining outcome are grade (see Hunt and Hess grade above) and age. Generally patients with Hunt and Hess grade I and II hemorrhage on admission to the emergency room and patients who are younger within the typical age range of vulnerability can anticipate a good outcome, without death or permanent disability. Older patients and those with poorer Hunt and Hess grades on admission have a poor prognosis. Generally, about two thirds of patients have a poor outcome, death, or permanent disability.

Prevention

Prevention of Cerebral Aneurysm
Consult with your doctor.