Similar to a
pacemaker, a stimulator device for epilepsy is implanted under the skin, either near your collarbone or on your skull. A wire (lead) under the
skin connects the device to electrodes implanted in your brain or attached to nerves that go to your brain. The doctor programs
the device either to produce weak electrical signals that travel to your brain at regular intervals or to notice abnormal electrical activity in the brain and send electrical signals to that area of the brain. These signals help prevent the electrical
bursts in the brain that cause seizures.
What To Expect After Treatment
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 partial seizures, who have not responded well to
antiepileptic medicines, and who are not candidates for epilepsy
Nerve stimulation is used in combination with other treatment. Nerve stimulation does
not eliminate the need for medicine. But it can help reduce the risk of
complications from severe or repeated seizures.
How Well It Works
Most of the evidence supports the use of vagus nerve stimulation. It reduces the frequency of
seizures that don't respond well to medicine and may make them less severe. About 2 out of 4 people say they notice that they have fewer seizures after surgery. But about 1 out of 4 people say they do not notice any benefit after surgery.1
The benefits of 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.
Studies show that VNS may also be effective in children.1
Nerve stimulation is considered safe. Side effects
occur in some people when the device stimulates the nerve. They include:
Hoarseness or slight voice changes.
Other risks of nerve stimulation have to do with the surgery to place the electrodes and the stimulator, including:
Numbness or tingling.
Pain where the stimulator device is placed under the skin.
Depression and memory impairment (with deep brain stimulation, or DBS).
What To Think About
Nerve stimulation is not a cure for
epilepsy, and it does not work for everyone. It does
not replace the need for antiepileptic drugs. It is most likely to be available
at an epilepsy center.
Englot DJ, et al. (2011). Vagus nerve stimulation for epilepsy: A meta-analysis of efficacy and predictors of response. Journal of Neurosurgery, 115(6): 1248–1255.
How this information was developed to help you make better health decisions.