New and safer brain stimulation treats depression
Bilateral epidural prefrontal cortical stimulation (EpCS), a new brain stimulation technique developed by MUSC researchers, has been found to help patients with treatment resistant depression. The study, lead by Ziad Nahas, M.D from the Medical University of South Carolina, found that the new and safer brain stimulation treatment significantly improved depression in a small study group.
Depression treatment using EpCS is targeted in the anterior frontal poles and the lateral prefrontal cortex of the brain. According to Dr. Nahas, “We focused on these two regions because they are part of a larger brain networks critical in regulating mood. Both play complementary roles integrating emotional and cognitive experiences and offer a distinct opportunity for targeted antidepressant treatments.” Nahas explains, “Cortical stimulation has several advantages provided that it shows efficacy in treating depression. It is reversible, non-destructive and potentially safer than other forms of invasive brain stimulation since the stimulating paddles don’t come in direct contact with the brain.”
The team studied four patients who had EpCS implanted over the right and left anterior frontal poles and the lateral prefrontal cortex. Treatment was individualized, and based on the patient’s responses, who were asked to signal when they felt a mood change that would indicate treatment of depression. The EpCS device implanted in the brain is connected to two small generators in the upper chest.
All of the patients in the study had been resistant to depression treatment using medications, psychotherapy, electroconvulsive therapy, or transcranial magnetic stimulation, vagus nerve stimulation.
The EpCS device was set to deliver an electrical current at periodic intervals for the study, at levels below seizure threshold. No stimulation was delivered at night.
After seven months, the researchers found a 54.9 percent improvement in depression symptoms in the group, based on the Hamilton Rating Scare for Depression, and 60.1 percent improvement of depression based on the Inventory of Depressive Symptoms Self Report.
The researchers say “Now that we have a proof of concept, we should aim at studying bilateral EpCS in larger placebo-controlled studies.”
The newer and safer brain stimulation treatment could offer new hope for patients who suffer from treatment resistant depression. Ten to thirty percent of patients given antidepressant medication and other therapy either fail to respond or their symptoms keep coming back.