A cerebral aneurysm is an abnormally dilated segment of a blood vessel. In some cases, the entire blood vessel widens and expands to resemble a balloon-like structure. The exact cause of many cerebral aneurysms is not clear and they can occur in patients of any age, including some which may occur as a congenital (“you are born with it”) defect in the lining of the blood vessels, which result in a continued enlargement of the aneurysm over time.
Risk Factors
Several factors can cause weakening of the blood vessel wall, including trauma, brain tumor and arteriovenous malformation (abonormal blood vessel development) from birth. Factors which have been shown to increase the risk of aneurysm rupture include smoking, high blood pressure, excessive alcohol consumption and atherosclerosis.
Symptoms
Occasionally an enlarging aneurysm can cause symptoms such as visual changes, seizures, facial pain and headache, due to the compression of the aneurysm on surrounding brain structures. CT or MRI imaging can be used to help diagnose a cerebral aneurysm as well as definitive diagnosis by a cerebral angiogram dye study, in the Interventional Radiology department. Unfortunately, the rupture of a cerebral aneurysm is usually sudden and occurs without warning. Symptoms of a ruptured aneurysm include:
- Loss of consciousness
- Severe headache with nausea or vomiting
- Numbness or decreased sensation in any part of the body
- Blurred vision
- Drooping eyelids
- Seizure
- Extreme lethargy
Once an aneurysm ruptures, blood accumulates in the brain and can compress and damage surrounding tissue. The tissue injury can also cause a spasm in the vessel, resulting in constriction and decreased blood flow to the surrounding brain area. The effect of a ruptured cerebral aneurysm can be serious neurological impairment or death. Early treatment of a ruptured or “leaking” cerebral aneurysm will follow the patient care model for “acute hemorrhagic stroke” including evaluation by the Emergency Response System (paramedics), Emergency Room evaluation and Neurosurgery consultation, rapid CT scan and prompt Interventional Radiology treatment as indicated.
Treatment
Early identification of a cerebral aneurysm and treatment is the goal to prevent further “expansion” of the aneurysm and potential rupture. The final goal of the treatment is to remove or cut off the blood supply to the cerebral aneurysm. In collaboration with neurosurgery, a decision will be made to consider surgical intervention and or Interventional Radiological-assisted treatment options by embolization (blocking off the artery by placing small coils or particulate “glue-like” matter) through a catheter placed into the cerebral artery, which is feeding blood supply to the aneurysm.
Often a combination of the two therapies is used, pre-surgical embolization to decrease the blood flow and surgical intervention to “clip” the cerebral artery aneurysm. Certain brain tumors are also treated in collaboration with our neurosurgery physician staff. This includes a pre-surgical Interventional Radiology embolization of the cerebral artery that feeds the brain tumor and subsequent surgical removal of the brain tumor mass, to decrease the risk of surgical intra-crainial bleeding. The procedure is most commonly performed in the Interventional Radiology department using general anesthesia, but has been performed with intravenous sedation, depending on the anatomical location of the aneurysm and neurological status of the patient.
Outcomes
Patients will have follow-up cerebral angiograms at six months and 1-year post-embolization and are followed by their neurosurgeon/neurologist/primary care physician for any changes in neurological status.