Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montreal, QC, Canada H2L 2W5.
J Biomech. 2010 May 28;43(8):1488-93. doi: 10.1016/j.jbiomech.2010.01.045. Epub 2010 Feb 19.
In the context of ultrasound dynamic elastography imaging and characterization of venous thrombosis, we propose a method to induce mechanical resonance of confined soft heterogeneities embedded in homogenous media. Resonances are produced by the interaction of horizontally polarized shear (SH) waves with the mechanical heterogeneity. Due to such resonance phenomenon, which amplifies displacements up to 10 times compared to non-resonant condition, displacement images of the underlying structures are greatly contrasted allowing direct segmentation of the heterogeneity and a more precise measurement of displacements since the signal-to-noise ratio is enhanced. Coupled to an analytical model of wave scattering, the feasibility of shear wave induced resonance (SWIR) elastography to characterize the viscoelasticity of a mimicked venous thrombosis is demonstrated (with a maximum variability of 3% and 11% for elasticity and viscosity, respectively). More generally, the proposed method has the potential to characterize the viscoelastic properties of a variety of soft biological and industrial materials.
在超声动态弹性成像和静脉血栓的特征描述中，我们提出了一种在均匀介质中诱发受限软异质体产生机械共振的方法。共振是由水平偏振剪切（SH）波与机械异质性的相互作用产生的。由于这种共振现象会将位移放大到非共振状态下的 10 倍，因此基础结构的位移图像对比度大大增强，从而可以直接对异质体进行分割，并由于增强了信噪比，因此可以更精确地测量位移。结合波散射的分析模型，验证了剪切波诱发共振（SWIR）弹性成像来描述模拟静脉血栓的粘弹性的可行性（弹性和粘性的最大可变性分别为 3%和 11%）。更一般地说，所提出的方法有可能对各种软生物和工业材料的粘弹性特性进行表征。
