How does it work?
The device is programmed to deliver electrical impulses in two ways:
• Automatically: the device is programmed by the doctor with a small computer. The doctor can change the amount of electricity and the frequency in which it is delivered. A common stimulation pattern is 30 seconds of stimulation every 5 minutes around the clock. The device is reprogrammed routinely and the setting is titrated up slowly. That means that the patient needs to visit the doctor periodically for the parameters of the device to be adjusted.
• Magnet: the patient or the caregiver carries a magnet that can activate the VNS. The magnet is mainly used when there is an indication that a seizure might occur or at the beginning of the seizures to try to abort it. Other uses of the magnet include stopping the impulses if the person with the VNS is having difficulty eating or has to do some public speaking and wants to avoid becoming hoarse when the device is on.
It is not completely understood the way in which this device and the electrical impulses it emits work. However, it is believed that they reach the brain and the result is the release of the same chemical (GABA) which is protective against seizures