VNS for Partial Epilepsy in Children

Partial epilepsy seizures disrupt the lives of children every day. Medications do not always help to control the epileptic seizures. In extreme cases, seizures from uncontrollable seizure disorders will cause severe brain damage over time. Vagus Nerve Stimulation (VNS), utilized in conjunction with medications, controls all types of seizures, including partial seizures. The VNS device is only about the size of a pacemaker but has a major role in improving the quality of life in epileptic children.

History

• During the 1930s, scientists realized that brain wave synchronization stopped when the vagus nerve was stimulated. The vagus nerve is one of the largest nerves leading into the human brain. Fifty years later, scientists had the technology to approach vagus nerve stimulation as a means to treat epilepsy. The Food and Drug Administration (FDA) approved the use of vagus nerve stimulation therapy for use in 1997.

Facts

• VNS therapy devices are small generators surgically implanted in the child's chest. Lead wires are threaded through the chest area to the neck. The wires are threaded up the neck and wrapped around the vagus nerve. The VNS is programmed to emit short pulses of energy for several seconds every few minutes, 24 hours a day. The frequency of the pulses varies according to the individual and doctors can change settings as needed.

Function

• Children who have partial seizures due to epilepsy often experience sensations warning them of an impending partial seizure. The children are taught to pass a small magnet over the VNS therapy device. Swiping the magnet over the VNS results in the generator emitting an extra pulse of energy to the brain through the vagus nerve. The extra pulsation stops the partial seizure, shortens the length of time of the seizure or minimizes the severity of the seizure. The magnets can be embedded into watches, key chains or belt tags for easy access.

Side Effects

• Children who have had a VNS implanted to assist in controlling partial seizures may experience hoarseness, a sore throat or infection at the incision site after surgery. Ongoing side effects of the VNS therapy device occur as the generator is sending pulses to the brain. The child may experience a tingling sensation in the neck, a tickling sensation in the throat, cough or experience a change in voice.

Considerations

• The VNS therapy device is monitored during doctor visits through a handheld computer and a wand that is placed over the device. Adjustments to the frequency of pulses emitted are completed at this time and the life of the battery is checked. VNS therapy devices operate due to batteries. The generator part of the device requires replacement every five to 10 years, depending on the frequency of the pulse it is programmed to emit and how often it is activated to stop partial seizures, resulting in drain on battery life. The procedure is performed under general anesthesia on an outpatient basis.