Department of Environment Systems, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan.
Development Team, Pixie Dust Technologies, Inc., Tokyo, Japan.
Adv Exp Med Biol. 2022;1364:119-143. doi: 10.1007/978-3-030-91979-5_6.
The investigation of cancellous bone using ultrasound measurements is not an easy task due to the solid complex trabecular structure filled with fluid-like bone marrow. It is expected that the ultrasound propagated in cancellous bone contains valuable information about the complex structure. In this chapter, the methods to derive useful information by the two-wave phenomenon-based ultrasonic assessment of cancellous bone is introduced. First, the measurements and mathematical descriptions of the two-wave phenomenon are presented in Sect. 6.1. Here, a conventional mathematical method to understand the phenomenon and fundamental results of the experimental measurements are introduced. Next, in Sect. 6.2, the computational simulation methods using models representing real bone structures, the numerical or statistical separation techniques of the two waves, and machine learning techniques for deriving material information are discussed. Finally, in Sect. 6.3, the results and the current limitations of the clinical assessment with a device using the two-wave phenomenon are introduced.
由于充满类似流体的骨髓的固体复杂小梁结构，使用超声测量研究松质骨并非易事。预计在松质骨中传播的超声波包含有关复杂结构的有价值信息。在本章中，将介绍基于双波现象的超声评估松质骨来获取有用信息的方法。首先，在第 6.1 节中介绍了双波现象的测量和数学描述。在这里，介绍了一种常规的数学方法来理解该现象和实验测量的基本结果。接下来，在第 6.2 节中，讨论了使用表示真实骨骼结构的模型的计算模拟方法，用于分离两波的数值或统计技术以及用于得出材料信息的机器学习技术。最后，在第 6.3 节中，介绍了使用双波现象的设备进行临床评估的结果和当前局限性。
