Sleefe G E, Lele P P
Lab. for Med. Ultrasonics, MIT, Cambridge, MA.
IEEE Trans Ultrason Ferroelectr Freq Control. 1988;35(6):749-57. doi: 10.1109/58.9332.
The authors propose a robust model for characterizing the statistical nature of signals obtained from ultrasonic backscatter processes. The model can accommodate frequency-dependent attenuation, spatially varying media statistics, arbitrary beam geometries, and arbitrary pulse shapes. On the basis of this model, statistical schemes are proposed for estimating the scatterer number density (SND) of tissues. The algorithm for estimating the scatterer number incorporates measurements of both the statistical moments of the backscattered signals and the point spread function of the acoustic system. The number density algorithm has been applied to waveforms obtained from ultrasonic phantoms with known number densities and in vitro mammalian tissues. There is an excellent agreement among theoretical, histological, and experimental results. The application of this technique for noninvasive clinical tissue characterization is discussed.
作者们提出了一个稳健的模型，用于刻画从超声背向散射过程中获得的信号的统计特性。该模型能够适应频率相关的衰减、空间变化的介质统计特性、任意的波束几何形状以及任意的脉冲形状。基于此模型，提出了用于估计组织散射体数密度（SND）的统计方案。估计散射体数量的算法结合了背向散射信号的统计矩和声学系统的点扩散函数的测量值。该数密度算法已应用于从具有已知数密度的超声体模和体外哺乳动物组织获得的波形。理论、组织学和实验结果之间存在极好的一致性。讨论了该技术在无创临床组织表征中的应用。
