When Seizure Medications Don’t Work, This Brain Implant Can Help

For about 1 in 3 people who have epilepsy, seizure medications don’t work. Known as drug-resistant epilepsy, this condition leaves you coping with unpredictable, disruptive seizures that can impact nearly every aspect of your daily life.

But a treatment called responsive neurostimulation (RNS) is starting to change that. And Hackensack Meridian Health offers it at its Level 4 comprehensive epilepsy centers, the highest level of accreditation from the National Association of Epilepsy Centers. This distinction means that you have access to the most extensive care available, including treatment for drug-resistant epilepsy.

“Hackensack Meridian Health prides itself in delivering exceptional care across all its facilities,” says Siddharth Kapoor, M.D., a neurologist and the regional chief for epilepsy at JFK University Medical Center. “With a collaborative team of epilepsy experts, we are unified in this mission to serve. Patients can freely move across the state and get their care anywhere that is convenient to them.”

Here's what to know about how RNS works and how it can help you. 

What Is Responsive Neurostimulation (RNS)?

A responsive neurostimulation device is like a pacemaker for the brain. It’s a small implant, roughly the size of a USB thumb drive, that sits within the skull and continuously monitors brain activity. When it detects abnormal patterns that could lead to a seizure, it delivers brief electrical pulses to disrupt or prevent the seizure from progressing. 

Unlike some treatments for drug-resistant epilepsy, RNS does not involve removing any part of the brain, says Alexander Buslov, M.D., a neurologist and the EEG lab director at Jersey Shore University Medical Center. And when seizures originate in two separate parts of the brain, it can target both, something that would be too high-risk with traditional surgery. 

“Just like everyone has a unique fingerprint, so is the location and starting point of seizures,” says Dr. Kapoor. “As doctors recognize the fingerprint of seizure onset, they program the device to target the seizure where it starts. Every day we use our fingerprint to unlock phones and doors, and just like that, we unlock the possibility of life free from seizures.”

How Does a Responsive Neurostimulation Device Work?

You’ll first go through a comprehensive evaluation, including a stay in the epilepsy monitoring unit, followed by neuropsychological testing and consultations with an epileptologist, a neurosurgeon and a nurse navigator.

Once cleared, a neurosurgeon implants the device into your skull and positions up to four electrodes in the areas of the brain where seizures originate. Surgery takes a few hours, and you’re typically home within two to three days.

 “There may be some pain and discomfort, but recovery is usually quick,” Dr. Kapoor says.

The system then collects brain activity data, which you upload at home for your doctor to review. You’re also given a handheld magnet to swipe over the device when you experience a seizure, says Dr. Buslov, helping physicians correlate reported symptoms with recorded brain activity. 

How Effective Is Responsive Neurostimulation for Epilepsy?

RNS has been shown to significantly reduce seizure frequency. An ongoing study found an 82 percent reduction in seizures after three years among 255 patients. 

And outcomes can improve the longer the device is in use. “Over time, we think the stimulation may be helping to rewire some of the brain’s circuitry,” says Dr. Buslov. “That could explain why the effect gets so much better.”

And because the system continuously gathers data, your physicians can also adjust and personalize treatment based on your brain activity patterns. 

“This is really personalized medicine,” says Dr. Buslov. “We’ve done an evaluation and identified the specific areas where the seizures are coming from for a patient, and we’re specifically targeting them. That looks very different from one RNS patient to the other.”

Dr. Kapoor adds another sign that the device works long-term: Most patients choose to keep it. “A second surgery is required to change the battery after a certain number of years, and the vast majority of patients undergo the second surgery to keep the device running.”

Who Is a Good Candidate for RNS?

RNS is FDA-approved for adults ages 18 and older whose seizures originate from one or two specific areas of the brain, says Dr. Buslov. You would generally need to have tried at least two anti-seizure medications at appropriate doses without achieving seizure control. If you receive the device, you’ll typically continue taking seizure medications alongside it.

But the medications may be lower doses or fewer in number, says Dr. Kapoor. And the bigger change is what becomes possible: "You may be able to drive because seizures are now under control."

RNS is not used for generalized epilepsy, in which seizures involve the entire brain.

Does RNS Have Side Effects?

As with any brain surgery, RNS implantation carries risks. The most significant is infection, which occurs in roughly 3 to 7 percent of cases, says Dr. Kapoor. If an infection occurs, it may require removal of the device. Bleeding has also been reported but is very uncommon.

For many people, the potential benefits can outweigh the risks. “Reducing seizures as impactfully as RNS does can change a person’s day-to-day life,” says Dr. Buslov. “For patients who are drug-resistant, almost any part of their life can be impacted by epilepsy, from driving a car to getting up on a ladder to change a light bulb. This gives them hope in ways they didn’t have before.” 

Next Steps & Resources:

• Meet our source(s): Alexander Buslov, M.D.; Siddharth Kapoor, M.D.
• Make an appointment online with a neurology provider near you, or call 800-822-8905.
• Learn more about our neuroscience services.