Can implant control seizures?

Researchers are testing the effectiveness of the Responsive Neurostimulator System (RNS) an implanted stimulator made by Neuropace in stemming seizures before they start in people with uncontrolled epilepsy. The RNS system contains a computer chip that is designed to detect abnormal electrical activity in the brain and delivers small amounts of electrical stimulation in response.

The system is implanted by a surgeon within the skull and beneath the scalp and then connected to two wires containing electrodes that are placed within the brain or resting on the brain surface in the area of the seizure focus. By continuously monitoring brain electrical activity, after identifying the 'signature' of a seizure's onset, the device delivers brief electrical stimulations with the intention of suppressing the seizure before any symptoms occur.

The study is being conducted by a team of researchers led by Michael Sperling at Thomas Jefferson University Hospital.An early study of the RNS system in 65 adults with medically uncontrolled epilepsy indicated that the device was safe.As part of this study, researchers are enrolling patients to determine if RNS was effective in predicting and preventing seizures in patients.The study participants will receive the implant but only half of them will have the device activated in the initial phase.

The others will have the device activated 16 weeks after surgery once the controlled phase was complete.'Patients who have the device activated one month after surgery will be monitored weekly at the epilepsy centre to tweak the chip's programming for optimal performance,' Dr. Skidmore said. Patients will also receive a device that was able to scan the chip for information about seizures just by holding a wand over the scalp. The information can then be downloaded by the patient onto a computer and sent via telephone to epilepsy researchers to review.