Department of Electronic Engineering, Yunnan University, Kunming City, Yunnan Province, China.
Cardiovascular Department, The Second Affiliated Hospital of Kunming Medical University, Kunming City, Yunnan Province, China.
J Healthc Eng. 2017;2017:8154780. doi: 10.1155/2017/8154780. Epub 2017 Sep 5.
This paper presents an assessment of physical meanings of parameter and goodness of fit for homodyned K (HK) distribution modeling ultrasonic speckles from scatterer distributions with wide-varying spatial organizations.
A set of 3D scatterer phantoms based on gamma distributions is built to be implemented from the clustered to random to uniform scatterer distributions continuously. The model parameters are obtained by maximum likelihood estimation (MLE) from statistical histograms of the ultrasonic envelope data and then compared with those by the optimally fitting models chosen from three single distributions. Results show that the parameters of the HK distribution still present their respective physical meanings of independent contributions in the scatterer distributions. Moreover, the HK distribution presents better goodness of fit with a maximum relative MLE difference of 6.23% for random or clustered scatterers with a well-organized periodic structure. Experiments based on ultrasonic envelope data from common carotid arterial B-mode images of human subjects validate the modeling performance of HK distribution.
We conclude that the HK model for ultrasonic speckles is a better choice for characterizing tissue with a wide variety of spatial organizations, especially the emphasis on the goodness of fit for the tissue in practical applications.
本文评估了同态 K（HK）分布模型对超声散斑的参数物理意义和拟合优度，这些散斑来自具有广泛变化空间组织的散射体分布。
基于伽马分布，建立了一组 3D 散射体幻影，从聚类到随机再到均匀散射体分布连续实现。通过对超声包络数据的统计直方图进行最大似然估计（MLE），获得模型参数，然后与从三种单一分布中选择的最佳拟合模型的参数进行比较。结果表明，在散射体分布中，HK 分布的参数仍然具有各自独立贡献的物理意义。此外，对于具有规则周期性结构的随机或聚类散射体，HK 分布的拟合优度更好，最大相对 MLE 差异为 6.23%。基于人体颈总动脉 B 型图像超声包络数据的实验验证了 HK 分布的建模性能。
我们得出结论，对于具有广泛空间组织的组织，HK 模型是一种更好的选择，特别是在实际应用中强调对组织拟合优度的关注。
