The United States Food and Drug Administration is to allow two pilots studies into the use of the Vagal Nerve Stimulator (VNS) to treat patients with chronic migraine headaches and Rapid Cycling Bipolar Disorder.
This news comes shortly after the latest news concerning the trials of using VNS to treat depression.
The vagal or vagus nerve is one of the many nerves which carry messages to and from the brain. Nerve fibres in the vagal or vagus nerve carry information from the body’s organs to the brain and are connected to the area of the brain believed to be involved in producing seizures. It is suggested that stimulation of the vagal or vagus nerve may be able to disrupt epileptic activity.
The VNS is a pulse generator, similar to a heart pacemaker, inserted into an opening in the chest. The generator is linked, via an under-the-skin cable to an electrode inserted into an opening at the side of the neck.
This electrode is then fitted around the vagal or vagus nerve. The generator is then programmed to continuously stimulate the nerve at varying frequencies, typically for 30 seconds every 5 minutes. The frequency can be adjusted to the individual patient’s needs after the operation by the doctor, using a small magnet. Patients who experience an aura or warning before a seizure can also use this special magnet to manually activate the generator.
Chairman of Cyberonics, the manufacturers of the VNS, Robert P. Cummins, said:
"Observations from VNS mechanism of action research and anecdotal reports of improvement in headaches in epilepsy and depression patients suggest that VNS may be an effective treatment for chronic migraine headache. We expect to begin the chronic migraine headache pilot within the next few months.".