Laboratoire de Mecanique et d’Acoustique, Centre National de la Recherche Scientifique UPR 7051, Marseille, France.
IEEE Trans Ultrason Ferroelectr Freq Control. 2011 Dec;58(12):2668-79. doi: 10.1109/TUFFC.2011.2129.
The structure factor model (SFM) is a scattering model developed to simulate the backscattering coefficient (BSC) of aggregated red blood cells (RBCs). However, the SFM can hardly be implemented to estimate the structural aggregate parameters in the framework of an inverse problem formulation. A scattering model called the effective medium theory combined with the SFM (EMTSFM) is thus proposed to approximate the SFM. The EMTSFM assumes that aggregates of RBCs can be treated as individual homogeneous scatterers, which have effective properties determined by the acoustical characteristics and concentration of RBCs within aggregates. The EMTSFM parameterizes the BSC by three indices: the aggregate radius, the concentration of RBCs with- in aggregates (the aggregate compactness), and the systemic hematocrit. The goodness of fit of the EMTSFM approximation in comparison with the SFM was then examined. Based on a 2-D study, the EMTSFM was found to approximate the SFM with relative errors less than 30% for a product of the wavenumber times the mean aggregate radius krΛκ <; 1.32. The main contribution of this work is the parameterization of the BSC with the RBC aggregate compactness, which is of relevance in clinical hemorheology because it reflects the binding energy between RBCs.
结构因子模型 (SFM) 是一种散射模型，用于模拟聚集红细胞 (RBC) 的反向散射系数 (BSC)。然而，很难在反问题的框架内实施 SFM 来估计结构聚集参数。因此，提出了一种称为有效介质理论与 SFM 相结合的散射模型 (EMTSFM) 来近似 SFM。EMTSFM 假设 RBC 的聚集可以被视为单个均匀散射体，这些散射体具有由聚集内 RBC 的声学特性和浓度决定的有效特性。EMTSFM 通过三个指标来参数化 BSC：聚集半径、聚集内 RBC 的浓度（聚集紧凑度）和系统血细胞比容。然后检查了 EMTSFM 逼近与 SFM 的拟合优度。基于二维研究，发现 EMTSFM 可以近似 SFM，相对误差小于 30%，当波数乘以平均聚集半径 krΛκ < 1.32 时。这项工作的主要贡献是用 RBC 聚集紧凑度来参数化 BSC，这在临床血液流变学中很重要，因为它反映了 RBC 之间的结合能。
