Vagal nerve stimulation is a method of treating seizures in children by delivering a regularly-timed streams of electrical impulses to the vagus nerve, which connects the brain to a variety of organs throughout the body. These small electrical pulses have been shown to calm the irregular brain activity that causes seizures.
Because around one-third of children with epilepsy are not responsive to medication, or have intolerable side effects to it, and due to seriousness of surgery, a vagal nerve stimulator can serve to calm or reduce seizures in children for whom medication alone does not ease their seizures.
What Is Vagal Nerve Stimulation?
The vagus nerve runs from the brain down each side of a child’s neck and branches throughout their body. It controls autonomic organs such as the heart, intestines and lungs, and it is made up of neurological fibers that carry information from the brain to the organs and back.
By stimulating the nerves leading to the brain, seizures are typically lessened. Currently, a device similar to a pacemaker called a vagus nerve stimulator (VNS) is implanted in the child’s chest. It is connected with wires and electrodes to the vagus nerve located in the left side of the child’s neck. The device will regularly send out small electrical impulses and can also be activated directly using a magnet in case of a seizure.
How Does Vagal Nerve Stimulation Work?
A VNS is a small device that is inserted under the chest wall of the child, with very small wires connecting it to the vagus nerve on the left side of the child’s neck. Three small platinum electrodes are firmly attached to the nerve tissue to ensure the electrical pulses from the device are connected and that they won’t become disconnected due to physical activity.
Sometimes children will spend a night in the hospital after receiving a VNS implant, but typically a child will be released to go home. Depending on the child’s needs, the device is usually activated and programmed around a week after surgery during the first post-operative checkup. The device is typically set to a lower strength of stimulation at first, then adjusted over time according to how the child’s response.
Because the vagus nerve is part of the autonomic system and helps regulate and control organs like the heart and lungs, some children may experience hoarseness, coughing or mild trouble swallowing during the period of stimulation. Side effects like these don’t occur while the device is not sending an electrical pulse.
Who Benefits from Vagal Nerve Stimulation?
A VNS can benefit children who suffer from a wide range of seizures, but is most often recommended for those children whose seizures are debilitating or are life-threatening. Children who are considered for a VNS implant typically have already tried a number of anticonvulsive medications without success and are not determined to be suitable to receive brain surgery.
Vagal nerve stimulation devices that do not require surgery are being developed, but are not yet available in the United States, so this option is currently only available to children who are judged suitable for surgery. However, newer nonsurgical devices will expand this treatment to some children who may otherwise not qualify to receive it.