Brain Aneurysms: To Operate or Not to Operate?
Oct. 30, 2000 -- For those with a brain aneurysm, it can be a bit like living with a tiny time bomb ticking in their head. What's worse, they might not know it's there, it doesn't bother them, and maybe it never will. In fact, the risk of the aneurysm exploding is only one in 100 each year. But if it does blow up, the chances of surviving are only one in two, and the odds of surviving without severe brain damage are only one in four.
Having a brain aneurysm -- a blood-filled pouch bulging out from a weak spot in the wall of a brain artery -- is just like that. Some people with aneurysms have headaches or vision problems, but most have no symptoms until the aneurysm ruptures or bursts open, bleeding into the brain tissue and causing stroke, brain damage, or even death. Between 1% and 5% of Americans may have unruptured brain aneurysms, and about 15,000 Americans each year have a stroke from a ruptured aneurysm.
Should screening be done to find unruptured brain aneurysms? And if found, should there be an operation? Tackling these issues head-on, the American Heart Association Stroke Council task force published guidelines for aneurysm screening and treatment in the Oct. 31 issue of Circulation: Journal of the American Heart Association.
"The consequences of aneurysm rupture are so severe that deciding which patients to treat is very important," task force chair Joshua B. Bederson, MD, tells WebMD. "All treatments carry some risk, which is why we need to individualize treatment.
"No one can tell if an aneurysm is going to rupture just by looking at it," says Bederson, an associate professor of neurosurgery and director of cerebrovascular surgery at the Mount Sinai Hospital in New York City. The task force studied features of the patients, the aneurysms, and the surgeons to try to decide when an operation should occur.
The largest international study to date showed that unruptured aneurysms smaller than 10 mm -- about the size of a raisin -- had a tiny risk of rupture, provided the patient had no earlier history of bleeding from a brain aneurysm, and higher risks associated with surgical treatment.
"This surprised many experts who were accustomed to treating nearly all identified unruptured aneurysms," says S. Claiborne Johnston, MD, MPH, an assistant professor of neurology at University of California at San Francisco who reviewed the guidelines for WebMD. As the task force could not rule out the possibility of bleeding even from small aneurysms, it recommended that patients with small aneurysms be considered for surgery, depending on their age and other factors.
"I'm very supportive of surgery in younger patients, but more conservative in the oldest patients with the smallest aneurysms," Bederson says. "It boils down to how old is the patient, and what is their life expectancy?"