The device is currently only made by Cyberonics, Inc. However, other "wearable" devices are being tested and developed by other companies that involve transcutaneous stimulation and do not require surgery. Implantation of the Cyberonics VNS device is usually done as an out-patient procedure. The procedure goes as follows: an incision is made in the upper left chest and the generator is implanted into a little "pouch" on the left chest under the clavicle. A second incision is made in the neck, so that the surgeon can access the vagus nerve. The surgeon then wraps the leads around the left branch of the vagus nerve, and connects the electrodes to the generator. Once successfully implanted, the generator sends electric impulses to the vagus nerve at regular intervals. The left vagus nerve is stimulated rather than the right because the right plays a role in cardiac function such that stimulating it could have negative cardiac effects.
Although the use of VNS for refractory depression has been endorsed by the American Psychiatric Association, the FDA's approval of VNS for refractory depression remains controversial. According to Dr. A. John Rush, vice chairman for research in the Department of Psychiatry at the University of Texas Southwestern Medical Center at Dallas, results of the VNS pilot study showed that 40 percent of the treated patients displayed at least a 50 percent or greater improvement in their condition, according to the Hamilton Depression Rating Scale. Many other studies concur that VNS is indeed efficacious in treating depression. However, these finding do not take into account improvements over time in patients without the device. In the only randomized controlled trial VNS failed to perform any better when turned on than in otherwise similar implanted patients whose device was not turned on. To better understand the opinions of the medical professionals relating to this treatment option a compilation has been prepared from the responses to CMS (Medicare) during the write-in period from 08/07/2006 - 09/06/2006 entitled " Letters from the Medical Professionals".
Other brain stimulation techniques used to treat depression include Electroconvulsive therapy (ECT) and Cranial electrotherapy stimulation (CES). Deep brain stimulation is currently under study as a treatment for depression. Transcranial magnetic stimulation (TMS) is under study as a therapy for both depression and epilepsy. Trigeminal Nerve Stimulation (TNS) is being researched at UCLA as a treatment for epilepsy.
An investigational treatment option for uncontrolled epileptic seizures is now being evaluated. Using the RNS System from NeuroPace, an implanted device provides “responsive stimulation” to the area of the brain that triggers the seizures, attempting to stop the seizure before it causes symptoms. The RNS System is being evaluated at approximately 28 different sites throughout the United States
Business developments.(Vagus Nerve Stimulation therapy system of Cyberonics Inc. )(Hillenbrand Industries Inc. makes new appointments)
Aug 01, 2005; Business developments ICD problems get Senate attention The cardiovascular device arena tends to blaze the technology trail in...