Cerebral (brain) aneurysms are weak bulging spots of the wall of an artery in the brain. Aneurysms can rupture leading to bleeding inside the head. It is estimated that intracranial aneurysms occur in 3 - 5% of people. About 30,000 aneurysms will burst each year in the U.S.
Approximately two million people living in the U.S. have unruptured aneurysms. Most people with aneurysms have no symptoms. Some aneurysms are at risk of growing larger and may rupture, which results in blood being released around the brain. This usually causes a sudden severe headache and can lead to severe neurological problems or even death. Treatment of aneurysms can include surgery or endovascular therapy.
Beaumont's interventional neuroradiologists can place a catheter (long, thin flexible plastic tubing) in the artery and guide it into the aneurysm. The goal of this treatment, known as aneurysm coil embolization or simply "coiling", is to block off the aneurysm by placing soft platinum coils through the catheter into the aneurysm.
By placing one or more small platinum coils through the catheter into the aneurysm, the body responds by forming a blood clot around the coil blocking off the aneurysm. By plugging the weak bulging section of the artery, the risk of rupture greatly decreases. Aneurysm coil embolization can be performed in both ruptured and unruptured aneurysms.
The procedure is done under general anesthesia and the anesthesia team is also present to closely monitor blood pressure, heart rate and rhythm in addition to blood oxygenation during the embolization procedure.
Coil embolization is most frequently used as a treatment for brain aneurysms where open surgery is associated with higher risk. Factors for deciding if a patient is a candidate for coiling treatment are the patient's age and health status as well as the location, size and shape of the aneurysm.
Benefits of Coil Embolization
Minimally invasive coil embolization allows treatment of cerebral aneurysms that previously were considered inoperable. This procedure is less invasive and requires significantly less recovery time than open surgery for aneurysm repair. The disadvantage of this procedure is the need for follow up for recurrence with MRA or cerebral angiography. The interventional neuroradiology staff will arrange the follow up exams.
Coil embolization of small aneurysms with small neck has better results than embolization of large or giant aneurysm with wide necks. Long term follow up has shown permanent success in more than 80% of aneurysms treated with coil embolization. A small percentage (approximately 10 - 15%) of aneurysms needs to be retreated with coils. A very small percent may have to be treated with traditional open surgery. View an animation of a coil embolization.
Risks of Coil Embolization
As with any invasive procedure in the blood vessels that supply the brain, there is a small risk of death or stroke, as well as less severe complications including infection, bleeding, allergic reaction and kidney failure. There is a 5 - 9% risk of stroke, aneurysm rupture and death.
Limitations of the Treatment
Technological advances such as the development of small stents and soft balloons have rendered the majority of aneurysms amenable to coil embolization. Unfortunately, large aneurysms with wide necks remain a challenge. Most neurosurgeons are knowledgeable about this widely available procedure as are an increasing number of neurologists.