Large scale study shows success of epilepsy surgery

Apr 11 2006

In one of the largest epilepsy surgery studies ever conducted, Mayo Clinic researchers have found that 81 percent of patients with intractable epilepsy become totally or nearly seizure-free six months following epilepsy surgery. Ten years later, 72 percent remained totally or nearly seizure-free.

Findings are published in the April issue of Journal of Neurosurgery.

"I think this is very exciting because the surgery not only can stop the seizures following the operation, but it can stop them for the long term," says Gregory Cascino, M.D., Mayo Clinic neurologist and study investigator.

Aaron Cohen, M.D., lead study investigator, agrees. "This shows us seizure surgery is durable -- it remains effective and safe over time." Dr. Cohen is a former Mayo Clinic neurosurgical resident who is now a neurosurgical fellow at University of Arkansas for Medical Sciences.

Epilepsy affects 3 million Americans. Thirty to 40 percent have intractable epilepsy: medications alone do not control the seizures, and the seizures have a disabling effect on quality of life.

"All other forms of treatment, specifically maximum anticonvulsant treatment, have failed for these patients," says Fredric Meyer, M.D., chair of Mayo Clinic Department of Neurologic Surgery and study investigator. "Often these patients are on two to three anticonvulsants and are still suffering from intractable epilepsy prior to surgery."

To conduct this study, the researchers analyzed the cases of 399 consecutive patients who underwent epilepsy surgery to remove the focal region of their disease in the brain at Mayo Clinic in Rochester, Minn., between 1988 and 1996. There were 214 females and 185 males, and the average age at surgery was 30.

Prior to surgery, quality of life is poor for these patients, the Mayo Clinic researchers explain.

"These patients typically can't drive or use dangerous machinery, have difficulties with work or can't work at all, or can't complete their education," says Dr. Cascino. "They usually would have several seizures per month and may be prone to having spells with loss of consciousness. They can injure themselves from seizures, drown or have sudden unexpected death due to epilepsy."

Quality of life typically improves dramatically after surgery, says Dr. Meyer. "If these patients have improved seizure control after surgery, which most of them do, then there is an incredible paradigm shift toward a better quality of life," he says. "These patients break out from the stigmata of epilepsy and find employment, often drive, and lead a productive life."

Risk with epilepsy surgery is relatively low: 4 percent of patients studied had medical problems due to anesthesia or other neurological complications during surgery. Risk varies by seizure type, where the seizure focal region is located, and other factors, according to Dr. Meyer.

Though epilepsy surgery is not risk free, Dr. Cascino notes that patients with intractable epilepsy are continually at risk already before surgery due to their disease. "This is a big operation for a big medical problem," he says. "These patients are medically, physically and socially affected by their disease."

Dr. Cascino says that it is cost-effective for society when surgery can stop a patient's seizures, due to the significant number of epilepsy patients who are unemployed or underemployed because of their seizures.

An appropriate candidate for epilepsy surgery is in good health, with the exception of epilepsy; is not responding to seizure medications; the region of the brain affected by the disease can be pinpointed; and the affected region of the brain can be safely extracted without damaging the surrounding area. Though 30 percent to 40 percent of epileptics might be candidates, the surgery is underutilized, according to Dr. Cascino. He says the surgery is available at medical centers designated level IV comprehensive epilepsy centers by the National Association of Epilepsy Centers (http://www.naecepilepsy.org). For those who are not surgical candidates, other treatment options are available, says Dr. Cascino.

"Patients suffering from epilepsy should seek an evaluation at an epilepsy center and not give up hope," says Dr. Meyer. "There may be very excellent options to help them."