Vagus Nerve Stimulation
Vagus nerve stimulation (VNS) is a treatment offered by the Center for Neuromodulation at Mount Sinai. This type of neuromodulation has been widely used since the 1990s to treat medically refractory epilepsy, that is, epileptic seizures that are not well-controlled by medications or other interventions. It is also used for patients who cannot tolerate the side effects of anti-seizure medications.
How does Vagus Nerve Stimulation work?
The vagus nerve is one of twelve cranial nerves, it being the longest running from the base of the brain all the way to the abdominal cavity. The vagus nerve has both motor and sensory functions.
Less invasive than deep brain stimulation, vagus nerve stimulation involves surgically implanting a small device under the skin in the chest, in a similar fashion to a heart pacemaker. That device, called a pulse generator, is attached to an insulated wire that sends mild electrical signals to the left vagus nerve in the neck. This is because the brain is not involved in surgery.
Those signals travel continuously along the vagus nerve into the brain stem and are then transmitted to various neural circuits in the brain. The electrical signals produced by the pulse generator are not felt by the patient, just as the normal electrical signals that tell your feet how to move when you walk occur below the threshold of human sensory perceptions.
Advanced Treatment for Epilepsy and Depression
Many patients who undergo VNS for the treatment of their epilepsy find they can reduce the amount of medications they need to take to control their seizures, thus reducing the side-effects of those medications. Patients are sometimes given a magnet that can be placed close to the pulse generator in their neck when a seizure is imminent or in progress to thwart a seizure or lessen its severity.
Vagus nerve stimulation is also used to treat major depression that is not well controlled by medication or psychotherapy or eletroconvulsive therapy.
“Studies suggest that at the three-year mark approximately 40 to 50 percent of patients who undergo this procedure for depression report a significant reduction of symptoms,” says Dr. Brian Kopell, Director of the Center for Neuromodulation.
VNS is done under general anesthesia and typically involves an overnight stay in the hospital, although the surgery can be done as a same day procedure. After the surgery, a neurologist programs the settings of the pulse generator—the frequency, amplitude and width of the electrical impulses—to match the unique needs of each patient.
Center for Neuromodulation
5 East 98th Street
New York, NY 10029