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 that travel to your brain at regular intervals to prevent seizures.
The responsive neurostimulator (RNS) is implanted in the skull, and 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.
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.
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.
Vagus nerve stimulation 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.footnote 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.footnote 1
The responsive neurostimulator (RNS) is an option for some people whose seizures do not respond to other treatments. RNS reduces the frequency of seizures by about half, and the benefits seem to increase over time.footnote 2
Nerve stimulation is considered safe.
of the vagus nerve stimulator occur in some people when the device stimulates the nerve. They include:
Other possible risks of both types of nerve stimulators include:
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.
Complete the special treatment information form (PDF)(What is a PDF document?) to help you understand this treatment.
CitationsEnglot 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.Thomas GP, Jobst BC (2015). Critical review of the responsive neurostimulator system for epilepsy. Medical Devices: Evidence and Research, 2015(8): 405-411. DOI: 10.2147/MDER.S62853. Accessed May 19, 2016.
ByHealthwise StaffPrimary Medical ReviewerJohn Pope, MD - PediatricsE. Gregory Thompson, MD - Internal MedicineMartin J. Gabica, MD - Family MedicineSpecialist Medical ReviewerSteven C. Schachter, MD - Neurology
Current as ofOctober 14, 2016
Current as of:
October 14, 2016
John Pope, MD - Pediatrics & E. Gregory Thompson, MD - Internal Medicine & Martin J. Gabica, MD - Family Medicine & Steven C. Schachter, MD - Neurology
To learn more about Healthwise, visit Healthwise.org.
© 1995-2017 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Last modified on: 8 September 2017