Investigating a Closed Loop Neural Control System to Optimize Sacral Neuromodulation

Background and Hypothesis:Approximately 16% of the American population suffers from overactive bladder, with 25-40% patients reporting unsatisfactory results following first line treatments. Sacral neuromodulation is a well-established, minimally invasive treatment option for several forms bladder bowel dysfunction that are non-responsive to pharmacologic or behavioral therapies. While more broadly applicable stimulus parameters being investigated, precise set nerve fibers whose activity regulates optimal function(s) not known, leading high levels variability between within over time. We hypothesize efficacy durability could be rapidly improved by continuously tuning electrical waveform pattern stimulation recruit fiber populations mediate micturition.
 Experimental Approach:We aim access sacral (S2-4) nerves implant recording stimulating bipolar cuff electrodes (FNC-400-V-R-C-2C-30, Micro-Leads, Somerville, MA, USA) measure evoked CAP at various combinations pulse amplitude duration. Simultaneously, we will changes in pressure using transducer attached catheter amplifier. By measuring how responds all applied able use an Autonomous Neural Control algorithm identify compound action potential response produces most robust pressure.
 Results:We developed surgical protocol, currently pending PACUC approval, allows us decode encode specific signatures represent firing distinct subsets fibers, each differing diameter, degree myelination, activation threshold, conduction speed, presumably function.
 Conclusion Potential Impact:This study aims act as proof concept system selects based on required produce desired rather than patient tolerance parameters, ultimately improving therapy.