Vagus nerve stimulation (VNS) is a therapy option available to patients for whom other therapy options have failed. VNS delivers a small amount of electrical current to the left vagus nerve. The electrical impulses are thought to desynchronize the abnormal electrical brain activity, therefore preventing the seizure.

Vagus nerve stimulation therapy involves undergoing an operative procedure for placement of a vagus nerve stimulator. The vagus nerve stimulator is composed of a generator about the size of a heart pacemaker and two electrode wires. The generator is placed under the skin at the left fold of the axilla, or left frontal chest wall. The two electrodes are wrapped around the left vagus nerve on the neck, tunneled under the skin and connected to the generator. The generator is activated and adjusted by your child’s neurologist using a special computer wand and laptop computer with special software.

What is vagus nerve stimulation (VNS) therapy?
VNS is a therapy that provides relief of seizures in patients for whom other treatments have failed. In general, the stimulator is used for patients when: 

• Seizure surgery is not an option
• Seizures are uncontrollable with a combination of anti-epileptic drugs, usually three or more

How does VNS work?
It is like a “pacemaker” for the brain. The stimulator sends a mild electrical stimulation through the left vagus nerve to calm overly excited nerve cells in the brain.

What are the parts of the VNS System? 

• Generator
• Weighs about 2 ounces
• Size and shape of a cardiac pacemaker
• Two electrodes
• Magnet

What effect can the stimulation have on seizures?
The stimulator can: 

• Stop the onset of seizures
• Decrease the intensity of seizures
• Decrease the post-ictal state (the time immediately after having a seizure)

Fifty percent of those who receive VNS experience an improvement of 50% or more.

What will happen if I choose VNS therapy?
Your child will need to be admitted to the hospital to have the VNS system implanted by a pediatric neurosurgeon. Usually, it will be necessary for your child to stay in the hospital overnight following the surgery.

What will happen in surgery?
Once your child is under anesthesia, the neurosurgeon will make two incisions—a small incision over the left side of the neck and the other over the left side of the chest. In surgery, two electrodes will be connected to the left vagus nerve in the neck, tunneled under the skin and connected to the generator in the left side of the chest. The surgery will last about two hours.

Who programs the VNS system to deliver the stimulation?
Your child's neurologist will program the device to automatically deliver stimulation at timed intervals around the clock. The device is programmed using a laptop computer with specialized software and a programming wand.

Are there side effects of the VNS system?
Yes, primarily: 

• Mild hoarseness
• Tingling sensation in the neck
• Cough
• Trouble swallowing

What special precautions should be taken with the VNS system magnet? 

• Don’t put the magnet on a color TV
• Keep it separated from credit cards
• Keep it away from computers and computer disks
• Report increased use of the magnet to your child’s neurologist

*Note: This information is intended to be used in consultation with your health care provider. It does not replace specific instructions, directions or warnings given to you by your child’s physician.