bipolar electrode
The vagus nerve stimulation (”VNS Therapy System”) surgery is a 90-minute out-patient procedure. It can be performed by a neurosurgeon, vascular surgeon or ENT. The components of the surgery include the following:
o A generator to provide the appropriate stimulation to the vagus nerve;
o A lead that is attached to both the generator and the vagus nerve;
o Associated equipment to assist with necessary implantation surgery;
o Equipment to assist with setting the stimulation parameters particular to the patient;
o Appropriate instruction manuals; and
o Magnets to suspend or induce stimulation manually
The implantation of the generator and lead into patients is generally performed on an outpatient basis. The battery contained in this generator has a finite life, which varies according to the model, the stimulation parameters and settings used for each patient. At or near the end of the useful life of a battery, a patient may, with the advice of a physician, choose to implant a new generator, with or without replacing the original lead.
Pulse Generator. The pulse generator is an implantable, programmable signal generator designed to be coupled with the bipolar lead to deliver electrical signals to the vagus nerve. The pulse generator is a battery powered device. Shortly before or upon depletion of the battery, the pulse generator may be removed and a new generator implanted in a short, outpatient procedure.
The Model 102, 102R, DemiPulse(TM) and DemiPulse(TM) Duo VNS Therapy pulse generators, the only pulse generators currently offered in the U.S., are similar in design and manufacture to a cardiac pacemaker. The generators are comprised of one printed circuit board and a battery hermetically sealed in a titanium case. Standard components are assembled on printed circuit boards using surface-mount technology. The assembled circuit boards are then tested and mounted with the battery in the titanium case, which is laser welded. A header to which the bipolar lead connects is added and each unit is subject to final release testing prior to being sterilized.
Bipolar Lead. The bipolar lead conveys the electrical signal from the pulse generator to the vagus nerve. The lead incorporates electrodes, which are self-sizing and flexible, minimizing mechanical trauma to the nerve and allowing body fluid interchange within the nerve structure. The lead’s two electrodes and anchor tether wrap around the vagus nerve and the connector end is tunneled subcutaneously to the chest where it attaches to the pulse generator. The leads are available in two sizes of inner spiral diameter to ensure optimal electrode placement on different size nerves.
Programming Wand and Software. Our programming wand and proprietary software are used to interrogate the device and to transmit programming information from a handheld computer to the pulse generator via electromagnetic signals. Programming capabilities include modification of the pulse generator’s programmable parameters (pulse width, amplitude, frequency and ON and OFF intervals) and storage and retrieval of telemetry data.
Tunneling Tool. The tunneling tool is a single use, sterile, disposable surgical tool designed to be used during surgical placement of the bipolar lead. The tool is used for subcutaneous tunneling of the lead assembly between the nerve site in the neck and the pulse generator site in the chest.
Accessory Pack. The accessory pack includes two resistor assemblies used to test the function of the device prior to implantation, the bipolar lead tie-downs and one hex screwdriver.
Charles Donovan was a patient in the FDA investigational trial of vagus nerve stimulation as a treatment for chronic or recurrent treatment-resistant depression. He was implanted with the vagus nerve stimulator in April of 2001. He chronicles his journey from the grips of depression thanks to vagus nerve stimulation therapy in his book:
Out of the Black Hole: The Patient’s Guide to Vagus Nerve Stimulation and Depression
His all inclusive book prepares depression sufferers to make an informed decision about this ninety-minute out-patient procedure. It is a “must read” before you discuss this treatment with your psychiatrist. A prescription for the procedure is required from an M.D. and it is covered by most insurance plans.
He is the founder of the [http://www.VagusNerveStimulation.com] Web Site and Bulletin.
Metroplasty with bipolar electrode
