What is Vagus Nerve Stimulator (VNS) Implantation?
A VNS is a device used to treat seizures when seizure drugs are not effective and surgery is not possible. VNS consists of a pacemaker-like generator that is implanted in the chest wall and is programmed by the physician to stimulate the vagus nerve in the neck. Thin wires are threaded under the skin and woven around the vagus nerve in the neck. This device often reduces the frequency of seizures and can also be activated by a patient or caregiver to stop seizures just as they are beginning.
Vagus nerve stimulation can work for any seizure type, but it is most often used for children with debilitating epilepsy. The VNS device often becomes more effective the longer it is in, and physicians typically know within six months if the VNS is helping to control the child’s seizures.
What to Expect Before VNS Implant Surgery
Children are given a general anesthesia prior to the surgery. Sometimes only a local anesthetic is used.
What to Expect During VNS Implantation
Two small incisions are required: one on the left lower side of the neck and a second along the left side of the chest. The VNS device, which is about the size of a silver dollar, is implanted into the chest wall.
The vagus nerve is located between the carotid artery and the jugular vein. Three small platinum electrodes are wrapped around the nerve and the wire is tunneled beneath the skin toward the left side of the chest. The electrode leads are attached to the generator, and the generator and leads are tested prior to closing the skin incisions.
What to Expect After VNS Implant Surgery
The generator may be turned on the day following the surgery or at the first post-surgical visit. We will assess your child in seven to 10 days for a wound check, and may turn on or adjust the generator. Parents will be shown how to use a magnet to control a seizure. Waving the magnet over the generator may stop or shorten a seizure.
Children who have VNS implant surgery usually return home the same day. Sometimes a hospital stay of one night is necessary.
Potential Complications of VNS Implantation in Children
Side effects of VNS therapy include hoarseness and discomfort in the neck when the generator is on. This indicates that the VNS is functioning. The incidence of children experiencing serious complications or unanticipated outcomes has been rare and outcomes have been excellent.