VNS involves the surgical implantation of a stimulator device – similar to implanting a pacemaker.
It is a small device that is implanted in the upper chest, and it regularly sends out electrical signals to the vagus nerve and brain. The VNS may be used when a person has poor seizure control and is not a candidate for epilepsy surgery.
By stimulating the vagus nerve, the VNS can help reduce the number and severity of seizures. About one third of people experience a 30 to 50 percent reduction in the number of seizures. Many people also experience a marked reduction in the severity of each seizure and faster recovery from a seizure. Less than 10 percent become seizure free. Also, the response to the VNS is not immediate and it can take several months to show its full effectiveness. Its effectiveness improves over time.
Other benefits include improvement in mood, alertness and overall quality of life. It has also shown positive effects on behaviour.
