Vagus nerve stimulation
This treatment strategy involves the concept of neuromodulation. Vagus nerve carries impulses to and from the brain. In a minor operation, the surgeon puts an electrical pacemaker under the skin of the chest. A wire or lead from that implant is connected to the vagus nerve in the neck. The implant works as a generator, sending intermittent impulses to the vagus nerve. The rate and strength of these impulses can be adjusted. A hand held magnet can also be used to increase the intensity of impulses when a seizure occurs. Newer implants use a cardiac rate detector. A slight increase in the heart rate serves as a hint of a seizure, and the implant automatically increase impulses.
The impulses sent by the generator interfere with the burst of impulses released when a seizure occurs. Vagus nerve stimulation is reported to be effective in at least 40% of the cases, where its efficacy is a measure of at least diminished frequency and severity of seizures, and not elimination of seizures. This therapy grants a feeling of control over the seizure and hence may improve quality of life for epileptic patients.
VNS therapy works as an adjuvant to drug therapy. It is only opted for when other interventions like medicine and surgery have failed to control seizure. In an ideal situation, VNS may help decrease the amount of drug load to control epilepsy. Some possible side-effects are:
- Heart palpitations
- Hoarseness of voice
- Difficulty in swallowing
- Sleep issues
- Tingling sensation
- Coughing and shortness of breath