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    Brain Aneurysms: To Operate or Not to Operate?


    "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?"

    Patients age 65 or older had four to five times as many complications from surgery -- including death -- as did patients younger than age 45. And as older patients have a shorter remaining life span than do younger patients, they have a shorter period of being at risk for aneurysm rupture.

    Almost half of patients die within 30 days of aneurysm rupture, and about half of the survivors have irreversible brain damage. "So if your brain aneurysm ruptures, you have only a one in four chance of doing well," Bederson says.

    Aneurysms that are large, growing, or causing symptoms are more likely to rupture. Other factors favoring surgery include history of rupture from another aneurysm or having a relative with an aneurysm. If unruptured aneurysms are not operated on, they should be followed periodically with brain scans to see if they are getting larger.

    "It's important to seek out a center that has a good record of treating aneurysms," Bederson says. "But determining which centers have a good record can be difficult, even for a surgeon, let alone for a layperson."

    Surgeons and hospitals have no central board accrediting them on their performance of aneurysm surgery, nor are they required to publish their own track record in this area. Studies in medical journals suggest that the death rate ranges from zero to 7%, and the complication rate from 4% to 15%.

    Although "the treatment of an unruptured [brain] aneurysm is generally very safe, and the outcome is usually good," Bederson explains that centers performing more than 10 aneurysm surgeries per year had less than half the death rate of centers rarely performing aneurysm surgery (5% vs. 11%).

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