Surgeons at Comprehensive Epilepsy Center Say Pacemaker-like RNS System Provides Innovative Approach to Stop Seizures Before They Start
NYU Langone Medical Center last month became the first hospital outside of a clinical trial site to implant a pacemaker-like device in the brain that may be a game-changer for patients with epilepsy.
The device, called the RNS System, was implanted April 17, 2014 in a patient with seizures that previously could not be controlled with medication, or intractable epilepsy, by Werner Doyle, MD, an associate professor in the Department of Neurosurgery at NYU Langone. The patient has recovered completely from the surgery.
The first-of-its-kind device is similar to an implantable cardioverter-defibrillator (ICD), which delivers electrical pulses to the heart to prompt it to beat a normal rhythm and provides a new alternative treatment to vagus nerve stimulation and surgical removal of the focus site – parts in the brain where the seizures originate -- for people with intractable epilepsy.
Prior to last month’s surgery, the only implants of the seizure-reducing medical device took place at U.S. medical centers that had previously researched the device’s effectiveness and safety, making NYU Langone the first non-study hospital in the U.S. and New York metropolitan area to offer the RNS System to patients.
"Medically intractable epilepsy is often a debilitating disorder that puts sufferers at risk from sudden loss of consciousness and uncontrolled movements. It stigmatizes patients and restricts their independence," said Dr. Doyle. "Epilepsy surgery is an important therapeutic option for patients, which can significantly or completely control their seizures and return their lives to normal. The RNS device improves our ability to control seizures with surgery and now offers patients who may not have been surgical candidates in the past a surgical option."
According to the Centers for Disease Control and Prevention, about 2.3 million Americans suffer from epilepsy, with about one in 26 people expected to be diagnosed in their lifetimes. Approximately one-third of patients do not respond to medications and face major challenges with daily living. Uncontrolled seizures may interfere with normal activities such as working, going to school and driving. Patients also face increased risk for anxiety, depression, injury, brain damage, and in rare cases, death.
The RNS System, manufactured by NeuroPace Inc. of Mountain View, Calif., is a responsive stimulation device that’s implanted in the skull along with brain electrodes to detect abnormal electrical activity in the brain associated with seizures. After two or more weeks of recording the activity, doctors program the device to specifically respond to these abnormal signals by delivering imperceptible electrical pulses to the brain that normalize the activity. The device essentially "reboots" the portion of the brain where the seizure is originating, thereby effectively interrupting the abnormal electrical activity before it spreads or causes its unwanted effects.
The RNS System received pre-market approval from the Food and Drug Administration in November 2013 to treat patients’ seizures that have not been controlled by two or more antiepileptic medications.
In clinical trials performed at medical centers across the U.S., including at Saint Barnabas Medical Center in New Jersey by Dr. Doyle and Orrin Devinsky, MD, director of the Comprehensive Epilepsy Center at NYU Langone, 55 percent of patients experienced a 50 percent or greater reduction in seizures two years post implantation.
"The RNS System represents one of the most important and innovative therapies to treat people with epilepsy," says Dr. Devinsky. "This new surgical therapy uses information to target and shut down points in the brain where seizures start without removing tissue, providing a novel option for patients with uncontrolled seizures."