FDA has approved a device to treat epilepsy to help reduce the frequency of seizures in patients who have not responded well to medications. According to the Epilepsy Foundation, epilepsy affects nearly 3 million in the U.S and is the third most common neurological disorder, after Alzheimer’s disease, and stroke. About 40 percent of people with epilepsy are severely affected and continue to have seizures despite treatment.
Epilepsy produces seizures affecting varied mental and physical functions. Seizures happen when clusters of nerve cells in the brain signal abnormally, which may briefly alter a person’s consciousness, movements or actions.
The RNS Stimulator manufactured by Neuropace, Inc. located in Mountain View, California is a small neurostimulator implanted within the skull under the scalp. The neurostimulator is connected to one or two wires that are placed where seizures are suspected to originate within the brain or on the surface of the brain.
“The neurostimulator detects abnormal electrical activity in the brain and responds by delivering electrical stimulation intended to normalize brain activity before the patient experiences seizure symptoms,” said Christy Foreman, Director for the Office of Device Evaluation in FDA’s Center for Devices and Radiological Health.
FDA’s approval was supported by a three month randomized control trial of 191 patients with drug-resistant epilepsy. The study showed that three months after the implanted device was turned on, patients experienced nearly 38 percent reduction in the average number of seizures per month as compared to approximately 17 percent reduction in the average number of seizures per month in patients who had the implanted device turned off.
Patients with RNS Stimulators cannot undergo MRIs nor can they undergo diathermy procedures, electroconvulsive therapy (ECT), or transcranial magnetic stimulation (TMS). The energy created from these procedures can be sent through the neurostimulator and cause permanent brain damage, even if the device is turned off.