A Proposal of Optimal Wavelet Based Smoothing for EGG Signal Trend Detection

Despite knowing the electrogastrography (EGG) for many years, there are still open issues regarding its measurement and processing. In the comparison with other electrophysiological signals, like is electrocardiography (ECG), we still miss a unified scheme for the placement of electrodes and EGG evaluation. In this paper, we analyze the possibilities of the Wavelet transformation for elimination of the ECG influence in the EGG records with the goal to obtain the EGG trend signal. In our analysis, we tested different settings of Wavelet based smoothing to evaluate an optimal setting for the Wavelet based smoothing filter. In this study, we bring an objective evaluation of the comparative analysis of individual Wavelet filters with the goal the EGG trend detection. EGG activity was measured via standardized laboratory conditions with system g.tec. All the measurements were done for set of 10 volunteers who consumed predefined same food to observe the gastric waves as for an empty stomach, and specific groceries.