肌肉中剪切波速度受力影响的有限元分析

Finite element analysis of shear wave velocity influenced by force in muscle

背景:肌肉中力分布的问题一直是研究的热点,且体外实验证明人体肌肉杨氏模量受外力影响变化明显,但活体生物肌肉中检测力的分布难度较大。剪切波弹性成像技术是一项有前景的非侵入性的成像诊疗手段,近年来被引入肌肉受力问题的研究中。目的:通过建立一个超弹性有限元肌肉模型证明剪切波速度和肌肉受力之间的关系,为剪切波弹性成像技术用于检测肌肉中力分布问题提供理论基础。方法:根据体外实验数据,建立超弹性肌肉有限元模型,轴向施加恒定荷载,研究不同受力情况下肌肉组织中剪切波速度变化。结果与结论:仿真结果显示随着荷载增大剪切波速度从6.1 m/s增加至13.1 m/s,且外力与速度线性相关,证明了剪切波弹性成像技术,可通过测量剪切波速度量化肌肉中里的分布。

BACKGROUND： Force distribution in muscle is still a hotspot. The in vitro experiments show that the Young＇s modulus of human muscle changes obviously under the influence of external force. However, it is difficult to detect force distribution in vivo. Shear wave elastography is a promising non-invasive imaging diagnostic method, which has been introduced into the study on muscle force distribution.OBJECTIVE： To testify the relationship between shear wave velocity and stress by establishing the hyperelasticity finite element model for muscles, so as to provide a theoretical basis for the application of shear wave elastic imaging to detect the force distribution in muscle. METHODS： The hyperelasticity finite element model was established based on in vitro experimental data. The shear wave speeds in muscle tissues under tension were studied by applying different statistic loads in axial direction.RESULTS AND CONCLOSION： The results showed that the shear wave speeds increased from 6.1 m/s to 13.1 m/s as the load increased. The speed was linearly related to the load. Therefore, shear wave elastography can measure the force distribution in muscle by measuring shear wave speeds.