Iterative Covariance-Based Removal of Time-Synchronous Artifacts: Application to Gastrointestinal Electrical Recordings

摘要: Objective: The aim of this study was to develop, validate, and apply a fully automated method for reducing large temporally synchronous artifacts present in electrical recordings made from the gastrointestinal (GI) serosa, which are problematic properly assessing slow wave dynamics. Such routinely arise experimental clinical settings motion, switching behavior medical instruments, or electrode array manipulation. Methods: A novel iterative Covariance-Based Reduction Artifacts (COBRA) algorithm sequentially reduced artifact waveforms using an updating across-channel median as noise template, scaled subtracted each channel based on their covariance. Results: Application COBRA substantially increased signal-to-artifact ratio (12.8 $\pm$ 2.5 dB), while minimally attenuating energy underlying source signal by 7.9% average ( $-$ 11.1 3.9 dB). Conclusion: shown be highly effective aiding recovery accurate marking events (sensitivity = 0.90 0.04; positive-predictive value 0.74 0.08) segments vivo porcine GI mapping data that would otherwise lost due broad range contaminating waveforms. Significance: Strongly with ultimately allowed rapid production isochronal activation maps detailing dynamics propagation intestine. studies can help characterize differences between normal dysrhythmic events, have been associated abnormalities, such intestinal ischemia gastroparesis. may generally applicable removing other biosignal processing domains.