A System and Method for Online High-Resolution Mapping of Gastric Slow-Wave Activity

Abstract

High-resolution (HR) mapping employs multielectrode arrays to achieve spatially detailed analyses of propagating bioelectrical events. A major current limitation is that spatial analyses must currently be performed “off-line” (after experiments), compromising timely recording feedback and restricting experimental interventions. These problems motivated development of a system and method for “online” HR mapping. HR gastric recordings were acquired and streamed to a novel software client. Algorithms were devised to filter data, identify slow-wave events, eliminate corrupt channels, and cluster activation events. A graphical user interface animated data and plotted electrograms and maps. Results were compared against off-line methods. The online system analyzed 256-channel serosal recordings with no unexpected system terminations with a mean delay 18 s. Activation time marking sensitivity was 0.92; positive predictive value was 0.93. Abnormal slow-wave patterns including conduction blocks, ectopic pacemaking, and colliding wave fronts were reliably identified. Compared to traditional analysis methods, online mapping had comparable results with equivalent coverage of 90% of electrodes, average RMS errors of less than 1 s, and CC of activation maps of 0.99. Accurate slow-wave mapping was achieved in near real-time, enabling monitoring of recording quality and experimental interventions targeted to dysrhythmic onset. This work also advances the translation of HR mapping toward real-time clinical application.

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

“…The reduced computational complexity and fast execution time of our algorithm may be particularly beneficial for real-time clinical analysis (e.g., [36], [37]). Whereas the EMD-ICA method applied to surface electrode intestinal recordings was shown to increase the SAR (5.38 dB) by eliminating the cardiac component of high frequency noise [19], COBRA achieved a stronger reduction when applied to both synthetic (8.9 dB) and porcine in vivo (11.1 dB) data sets.…”

A system for automated quantification of cutaneous electrogastrograms

“…Application of the methods to a larger patient population will enable us to assess the clinical utility of cutaneous EGG. Similar to multi-electrode, real-time automated analysis in serosal slow wave recordings [10], [11], advances in recording techniques, along with mathematical modeling and signal processing algorithms may enable cutaneous EGG to discriminate dysrhythmic slow wave patterns and aid as a diagnostic.…”

“…The amplitude of the slow wave signal is another parameter that is seldom used as a discriminating factor, but has been shown to be vital for detecting dysrhythmic activity from serosal recordings [9]. Analysis of serosal signals have largely been automated, motivated via multi-electrode mapping, and techniques been implemented in real-time [10], [11]. However, the analysis of cutaneous EGG in most research centers is performed manually which is prone to bias and subjectivity.…”

Extending the automated gastrointestinal analysis pipeline: Removal of invalid slow wave marks in gastric serosal recordings

“…Its usage in clinical research is being driven by the development of automated and real time techniques for analysis, allowing researchers to traverse large amounts of data in a short period of time [18], [6], [11]. Noise is omnipresent and cannot be avoided or predicted accurately.…”