Vagus Nerve Stimulation
It has been found that an estimate of about 1% of the world’s population suffer from Epilepsy. 30% of these patients are treated with medication. Before Vagus Nerve Stimulation was introduced the only option to treat epilepsy was Surgery. However, not everyone would be a suitable candidate for a surgery and surgery is not really a solution for medically refractory seizures.
Vagus Nerve Stimulation was designed to help prevent seizures, wherein a small device (similar to a pacemaker) is implanted in the chest just under the skin. The primary function of it would be to send regular mild pulses of electrical energy to the brain through the vagus nerve. This device is also known as a “pacemaker for the brain”.
The vagus nerve is part of the autonomic nervous system that controls all the non-voluntary functions of the body, like breathing, heart rate, etc.� The nerve passes through the neck and connects the chest and abdomen to the lower part of the brain.
Causes
Some of the causes why seizures occur are listed below:
- Tumor
- Low blood sugar / sodium
- Head injuries
- Drug abuse
- Stroke / Hemorrhage
- Birth injuries
Procedure
An incision is made along the outer side of the chest on the left side and the device is implanted under the skin. Next, the surgeon makes a second incision, horizontally, in the left side of the lower neck along a crease of the skin. The surgeon then carefully winds the wire from the stimulator around the vagus nerve. The brain itself is not involved in this surgery.
The device that is implanted is a flat round battery which is about an inch and a half across with a thickness of 10-13 millimeters (depending on the model that is used). The surgery lasts for about 60-90 minutes and the patient would be under general anesthesia.
Associated Risks
As with any surgery, there would be a certain degree of risks related to Anesthesia. In addition there could be rare complications like bleeding during the surgery.
Recovery
Once the procedure is completed the patient is shifted to a recovery room. A one night stay at the facility may be required.
Before the patient is discharged, the neurologist programs the strength and timing of the impulses according to the need of the individual. The settings can be changed and programmed without entering the body just by using a programmed wand that is connected to a laptop.
The device is programmed such that it turns on for a period of time and then turns off for another stretch of time. The device runs continuously usually with 30 seconds of stimulation alternating with 5 minutes of no stimulation.
Holding a magnet near the device causes it to become active. For people with warnings before their seizures, activating the device with the help of a magnet can help stop the seizure.
It has also been seen that patients without warning signs, experience improved seizure control.
