Correlation between lung maturity and backscatter coefficient calculations in fetal lung. Simulations

Abstract

Fetal lung maturity is a public health problem, and developing quantitative ultrasonic (QUS) techniques has become a possible way of assessing lung development. To estimate the feasibility of using quantitative medical ultrasound, we performed numerical simulations of radio frequency signals scattered from lung tissue. Given the distribution of sizes of alveoli, and wall lining thicknesses corresponding to different stages of lung maturity, we calculate the effective speed of sound using an effective medium approximation. The attenuation and backscattering coefficient is calculated from many-body scattering techniques. Also, for the attenuation and the backscattering coefficient, different statistical configurations are considered to determine the correlation between size of alveoli and acoustic properties. The results using QUS are compared to light scattering techniques (1). Our simulations are compared with ultrasonic measurements made with sponges with different pore sizes following the work of . Once the measurements are analyzed, the sponges are cut and analyzed under a dark-filed microscope to obtain the average size of pores. As a proof of concept, we show that quantitative medical ultrasound can provide information on fetal lung maturity accurately. (1) M. S. Durkee, G. K. Fletcher, C. Carlson, K. Matheson, S. K. Swift, et al. Opt. Lett. Vol. 43, No. 20, 5001 (2018).