Implantable, transcutaneously powered neurostimulator system to restore gastrointestinal motility

This neurostimulator design addresses a deficiency in a promising new method for imposing a pre-designed and electrically-invoked motility patterns in the gastrointestinal (Gl) tract. Sequential Neural Gastrointestinal Stimulation (SNGES) has been shown to be effective in artificially restoring the motility of the stomach and the colon. However, the availability of an implantable device to implement this innovative stimulation protocol has been lacking. The work presented in this paper was aimed at designing a transcutaneously powered implantable device to facilitate SNGES testing. Discrete electrical components and a Complex Programmable Logic Device (CPLD) were used to rapidly prototype the neurostimulator. Transcutaneous Energy Transfer (TET) powered the device to eliminate the need for an implantable battery. This research resulted in the design, implementation, and testing of an innovative transcutaneously powered device that is small and safe enough to be chronically implanted in experimental animals or humans. The device conforms to the stimulation algorithm used in the SNGES method for restoring GI motility. A detailed design procedure addresses key issues such as charge balance, tissue heating, and biocompatibility. This design procedure lays the foundation for the future architecture of a mixed-signal ASIC based neurostimulator that would lead to further minimization of power consumption and size.