Comparison between incident and reflected of two modes waves correlation with various porosities and thicknesses of bone phantom

Abstract

The accuracy of the ultrasound measurement using through transmission technique to estimate bone quality based on fast and slow wave analysis is getting better but limited to the certain part of the skeletal site. Thus, the pulse echo technique with the application of fast and slow wave analysis is proposed to solve the problem as the technique only uses one transducer to operate. The objective of this paper is to conduct experiments using through transmission and pulse echo technique to study the relationship of fast and slow wave with various porosity of three different thicknesses of polyurethane foam. Fast and slow waves will be separated from the "incident" and "reflected" wave (mix wave) by utilizing bandlimited deconvolution method. Then, the ultrasound parameters for mix, fast and slow waves for both incident and reflection waves are computed, plotted against porosity for each thickness and the results is compared in terms of the correlation coefficient. The overall results show that, the slope of attenuation of the incident fast waves shows a good relation, while the slope of attenuation of the reflected slow waves shows a good association with porosity for every thickness. Besides, the reflected wave may affected by scattering effect more compared to the incident wave, thus, cause the correlation between reflected wave parameters with porosity is lower. The overall results suggest, considering fast and slow wave to estimate bone quality might help to improve the measurement accuracy for both techniques.