A customer was telling me today about his dad's pacemaker. Modifications are made by the doctor by telephone with the earpiece held over the heart. Apparently the doctor uses a device that emits audio tones for various programming functions. This way the pacemaker can be fine tuned to the recipient’s particular needs, even as they change over time. On a similar vein, my mother recently had a spinal cord stimulator implanted. Used for relief of severe and chronic pain, it blocks the pain signal to the brain by emitting a number of patterns of electrical stimulation to two electrodes implanted along the spinal cord. The battery and stimulator are implanted in the back, and the battery lasts for six years. Minor surgery is required to replace it! Adjustments are made with a radio transmitter contained in a hand-held wand that is waved over the area of the implant. I think about a dozen different stimulation patterns can each be run exclusively, or simultaneous to some or all other patterns. Really, it is amazing technology. Without this technology, my mom can't live without IV morphine and permanent hospitalization.