March 18, 2010 -- Deep brain stimulation may offer a new treatment option for fighting epileptic seizures in those who don't respond well to other therapies.
A new study shows deep brain stimulation, which involves implanting tiny electrodes in the brain that release electrical pulses, reduced the frequency of partial seizures and secondarily generalized seizures -- partial seizures that spread throughout the brain.
Overall, researchers say more than half of those treated experienced a reduction in epileptic seizures of at least 50%.
Earlier this month, an FDA advisory panel recommended approval of deep brain stimulation as an epilepsy treatment based on the results of this study.
Epilepsy is a common neurological disorder that causes recurrent seizures that can cause temporary loss of consciousness, convulsions, or confusion. Antiepileptic drugs are the standard treatment for controlling and reducing epileptic seizures, but the drugs don't work effectively for up to a third of people with epilepsy.
The study, published in Epilepsia, evaluated the safety and effectiveness of electrical deep brain stimulation in 110 adults who had epileptic seizures occurring at least six times per month and did not respond to antiepileptic drug treatment.
In the first phase of the study, researchers implanted electrodes in all of the participants, but only half received electronic stimulation for three months. The results showed that those who received deep brain stimulation had a 40% reduction in epileptic seizures compared with a 15% reduction in the group that did not receive electronic stimulation.
In addition, the seizures considered most severe by the participants were all reduced among those receiving stimulation.
After the initial three-month phase, all of the participants received
electronic deep brain stimulation and were followed for about two years. After
about two years, 54% of participants had a reduction in the frequency of their
seizures of at least 50%.
Fourteen participants (13%) were seizure-free for at least six months of the trial.
There were five deaths during the study, but none was believed to be device related. The most commonly reported side effects were depression and memory problems, which were usually extensions of previously existing problems according to researchers.
"Electrical deep brain stimulation (DBS) is a promising therapy for epilepsy," says researcher Robert Fisher, MD, PhD, director of the epilepsy center at Stanford University, in a news release. "While our study did not produce serious complications, DBS therapy is invasive and serious complications can occur."
Fisher says additional study is needed to determine who are the best candidates for deep brain stimulation and establish the optimal rates of stimulation.