A 3D Ultrasound Model of Red Blood Cell Aggregation

An ultrasonic simulation method of erythrocyte aggregation with different levels in the blood is presented in this paper. Gamma distribution and Gaussian distribution are used simultaneity. A set of 3D ultrasound phantoms based on Gamma distribution gamma distributions is built to be implemented from the random to clustered scatterer distributions by adjusting the shape parameter $\alpha$ and scale parameter $\beta$ and the parameters of normal distribution. In the simulation study, firstly, Matlab platform is used to establish the geometric model, and the shape parameters $\alpha$ of gamma distribution are set as 1, 0.5, 0.1, 0.05, 0.02, 0.01, respectively. Secondly, the ultrasonic echo radio-frequency (RF) signals of each scattering model are obtained by the Field II software, and the echo envelope signals are calculated by the Nakagami distribution parameters. To verify the effectiveness and feasibility of the simulation model, in vitro experiments are carried out with the hematocrit levels of 40%. Six degrees of RBC aggregation suspension samples are acquired by diluting plasma concentration, and the plasma concentrations (the ratio of plasma to PBS-Plasma solutions) are 0%, 15%, 30%, 45%, 60%, 75%, respectively. The echoed ultrasound RF signals and their B-model images are obtained by using a 40-MHz linear array transducer in vitro experiments. Finally, Nakagami parameters $m$ and $\Omega$ of the backscattered RF signals of simulation experiments and in vitro experiments are calculated and compared. And the relative error of the normalized Nakagami $m$ and $\Omega$ between simulation and in vitro experiments are 0.00, 0.0050, 0.0003, 0.0019, 0.0026, 0.0050 and 0.00, 0.0795, 0.0054, 0.0715, 0.0241, 0.0832, respectively.