Using an electrical bio-impedance method to detect and evaluate gastric motility for erosive gastritis patients

Abstract

In order to investigate the complex course of electricity and mechanism of erosive gastritis (EG), including its rhythm, transmission, gastric empty course and the influences of them, it is necessary to extract gastric motility feature indexes. Methods: According the clinic standardization, 30 volunteers of erosive gastritis were selected. The signal processing device was designed by Chongqing University of Posts and Telecommunications. Both signals impedance gastric motility (IGM) and EGG collected from body surface are decomposed by Multi-resolution Analysis (MRA). Wavelet transform is addressed to separate the IGM signal from breathing and blood flowing impedance signals. By the means of energy and frequency spectrum analysis technic, the signals can be classify according to the dominant power and dominant frequency. Some indexes such as frequency of EGG and IGM, signal power spectrum and dynamic spectrum, the rates of rhythm and power for the normal EGG and IGM and so on can also be calculated. Results: The experiments of gastric motility measurement and evaluation are executed including before teating and after a week. The parameters have changed significantly between health adult and patient (P<0.05). The volunteers feel that the symptom is not disappeared. The feature of EGG has changed significantly (such as power instability coefficient, frequency instability coefficient P<0.05), otherwise those of impedance signal has not (P>0.05). The results of the experiments show that the method based on the synchronous measurement of EGG and IGM can provide a non-invasive way to investigate and evaluate gastric motility situation correspond ing gastrointestinal physiology and pathology conditions. © 2009 Springer-Verlag.