ANNOUNCER: Epilepsy can be treated in a number of ways, but is most commonly controlled through the use of anti-seizure medications. Although there are a wide variety of effective medications on the market, they do not work for everyone. Some people with epilepsy develop what's known as medication-resistant or refractory epilepsy and are not able to become seizure free on anti-seizure drugs.
ORRIN DEVINSKY, MD: There are probably no fewer than half a million people in this country who have seizures that persist despite taking one, two, three or even more medications. So it's this group of people with refractory epilepsy who are not candidates for surgical therapy, who may have tried other approved devices, but whose lives continue to be significantly negatively affected by seizures and usually medication side effects together.
ANNOUNCER: There are currently several experimental devices in development that may offer some hope.
ORRIN DEVINSKY, MD: Two of the most promising ones, which are somewhat down the road are the Medtronic deep brain stimulator, which targets a part of the brain in the center called the thalamus, which has a very strong regulatory function in controlling activity throughout the brain, and it delivers small currents of electricity to that area in the hope of downplaying or reducing the amount of seizure activity.
There's another device made by a company, NeuroPace, that is targeting the outer portion of the brain, the area that seizures may come from. This device would also provide electrical stimulation, and the hope is, with either or both of these devices down the road, that they could be activated at the time a seizure is about to occur.
So the concept would be, if someone were about to have a seizure, the device would recognize it through a recording electrode, activate the current and shut down the seizure. And then, in the future, potentially even recognize the electrical signals that tell us a seizure's coming soon and then potentially stimulate them to even prevent the earliest generation of a seizure, nevermind shutting it down once it begins.
ANNOUNCER: Another new device in development is the intracranial anti-epileptic drug delivery system.
ORRIN DEVINSKY, MD: The intracranial anti-epileptic drug delivery system // is a device that would be able to store medication in small amounts in a reservoir, let's say in the upper chest, and then deliver it locally to a region of the brain from which seizures arose.
And the advantages of such a delivery system are multiple. For one, the medication would not need to be taken orally. It would not need to pass through the GI system and the liver and the bone marrow and the heart and the kidneys and the skin, which can all cause significant side effects for many people.
In addition, the drug going through the blood system, goes to all parts of the brain. And it may be that the seizures literally come from one or two percent of abnormal brain tissue and yet we're dousing 100 percent of the brain cells with the medication. How much better would it be to give five times the concentration of the medication to that two percent of already abnormal cells and not hit the other 90 percent of perfectly normal, well-functioning brain cells with medications that can have side effects, which is now what we currently do.
ANNOUNCER: As with any new medical product, safety is always a concern.
ORRIN DEVINSKY, MD: The safety of the intracranial anti-epileptic drug delivery system is too young to know. In principle, it should be very safe. I think, with any of the devices that go into the brain, whether it be one of the stimulation devices or a drug delivery device, perhaps the biggest fear would be that of infection, which, in well-controlled and experienced centers, should be less than one percent, but I think we need to get more experience to know what that number would be. Apart from that, I think the risks are probably quite low.
ANNOUNCER: Although it is uncertain when these devices will be available, experimental products such as these offer an opportunity to achieve a seizure-free existence to people with the most extreme forms of epilepsy.
ORRIN DEVINSKY, MD: I think, as one looks to the future and other techniques for the treatment of epilepsy, there will be several out there. Gene-based therapies, although we hoped they would be out here five years ago for cancer, for neurological disorders; they're not quite there yet. And yet the promise of gene therapies is enormous, so I think that's one form of therapy that will probably be out there soon.
There are many drugs in development, and then hopefully we will learn, with some of the devices that we have already, how to use them better and to target their effectiveness in a much greater way.