Nerve Stimulation for Epilepsy
There are two types of stimulator devices for epilepsy. In both types, the devices send electrical signals to the brain to prevent the electrical bursts that cause seizures.
The vagus nerve stimulator (VNS) is implanted under the skin, near your collarbone. A wire (lead) under the skin connects the device to electrodes attached to the vagal nerve that goes to your brain. The doctor programs the device to produce weak electrical signals. These signals travel to your brain at regular intervals to prevent seizures.
The responsive neurostimulator (RNS) is implanted in the skull. Lead wires connect the device to the area of the brain that is causing the seizures. The doctor programs the device to notice abnormal electrical activity in the brain and send electrical signals to that area of the brain.
Nerve stimulation is used along with other treatment. It doesn't get rid of the need for medicine. But it can help reduce the risk of complications from severe or repeated seizures.
What To Expect
The nerve stimulator can start working right after the surgery. You may notice a slight bulge in the area where the device is. And the surgery will leave small scars where the wire leads were placed and where the device was implanted.
Why It Is Done
Nerve stimulation can be used in some people who have generalized or focal seizures, who haven't responded well to antiepileptic medicines, and who aren't candidates for epilepsy surgery.
How Well It Works
The vagus nerve stimulator (VNS) may reduce the frequency of seizures in some people with epilepsy.
The benefits of the VNS seem to increase over time.
For people who can sense when they are about to have a seizure, turning on the VNS using their hand-held magnet can sometimes prevent the seizure. It may also shorten a seizure already in progress.
The VNS may also work well in children.
The responsive neurostimulator (RNS) is an option for some people whose seizures don't respond to other treatments. RNS reduces the frequency of seizures by about half. And the benefits seem to increase over time.
Nerve stimulation is considered safe.
Side effects of the vagus nerve stimulator occur in some people when the device stimulates the nerve. They include:
- Throat pain.
- Hoarseness or slight voice changes.
- Shortness of breath.
Other possible risks of both types of nerve stimulators include:
- Numbness or tingling.
- Pain where the stimulator device is placed under the skin.