An automatic procedure for the extraction of parametric images of the myocardium from integrated ultrasonic backscatter signals

An automatic procedure for the extraction of quantitative parameters which characterize the Cyclic Variation (CV) of ultrasonic Integrated Backscatter Signal (IBS) within the cardiac cycle is proposed. After image realignment, the following CV parameters are quantified for each pixel, by harmonic analysis of the corresponding pixel intensity along the cardiac cycle: the modulus of the first (A0) and the second (AI) Fourier coefficient and their ratio (A1/A0), the phase (PI) of the first harmonic component. Parametric images are then computed. A population of 12 subjects was considered; automatic measures of CV parameters extracted from 6 regions of interest (11x11 pixel size) for each examined view were compared to the manual ones, obtained by classic acoustic densitometry analysis. The good linear correlation (r, A0:0.98; A1:0.99; A1/A0:0.98; P1:=0.97) verify the reliability of the proposed automatic approach.