Deep Brain Stimulation: Treating the Most Complex Epilepsy Cases

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Epilepsy is one of the most common neurological conditions, affecting up to 5 million Americans. People can be born with Epilepsy, or develop it at any point in life. It affects people of all backgrounds. And up to a third of Epilepsy patients aren’t able to control their seizures with medication. All seizures in Epilepsy are caused by abnormal electrical activity in the brain, but the parts of the brain affected, the type and severity of the seizures, can vary widely. “Epilepsy can range from people who, you’d never know they have seizures, to people who just drop,” says Eyiyemisi Damisah, MD, a neurosurgeon at Yale. While some patients may stare blankly for a few seconds during a seizure, for others with uncontrollable seizures, they could fall and convulse on the floor, making it difficult to do everyday things like driving, holding down a job, or participating in sports. “It is quite disruptive to one’s life,” Dr. Damisah says. For patients who haven’t found success in managing their seizures through medications, surgery is considered. “They’ll go to a neurosurgery workup to find out, can we identify where the seizures are coming from?” explains Franklin Brown, PhD, a neuropsychologist at Yale. He uses cognitive tests to help evaluate what part of the brain is being affected by the abnormal electrical activity. But only about 20 percent of these patients are candidates for resective surgery – in other words, removing areas of the brain where the seizures originate. “Sometimes there are seizures that come from locations where you can’t take part of the brain out, or they’re coming from multiple locations,” says Dr. Brown. Surgeons can’t remove affected areas of the brain if it could impact the patient’s language abilities or motor skills, for example. Deep Brain Stimulation is a newer type of surgery that allows surgeons to modulate electrical activity in the brain, rather than removing any of the brain tissue itself. “For those patients, Deep Brain Stimulation is critical,” explains Dr. Damisah. “Deep Brain Stimulation modulates the circuitry and helps control the seizures while sparing the critical areas of the brain.” The procedure, which is performed while the patient is asleep, involves placing electrodes in a central hub of the brain called the Thalamus. The electrical impulses are programmed and modulated via a small, battery-operated device similar to a pacemaker. The surgery is performed using intraoperative MRI guidance, which allows surgeons to see and navigate the brain in real time to ensure the correct placement of the electrodes within the Thalamus. DBS is used in conjunction with seizure medications, but patients may be able to decrease the dosage over time to lessen unpleasant side effects of the medication. Because Yale sees so many complex cases of Epilepsy, Dr. Brown describes it as an ideal place to go for treatment. DBS for Epilepsy has only been fully approved since 2018, but researchers at Yale continue to investigate to better understand the pathology and potential treatments for Epilepsy. “Yale has a very collaborative program, and this is also backed by intense scientific, basic and clinical research to actually push the field,” Dr. Damisah says. “This is an exciting time in Epilepsy,” says Dr. Damisah. “Almost everyone who has medication refractory Epilepsy has a treatment option.”