Mechanical Engineering Department, University College London, London, WC1E 7JE, UK.
ibs.GRANADA, Instituto de Investigación Biosanitaria, 18012, Granada, Spain.
Sci Rep. 2022 May 6;12(1):7448. doi: 10.1038/s41598-022-11490-4.
Fractional viscoelastic rheological models, such as the Kelvin Voigt Fractional Derivative model, have been proposed in the literature for modelling shear wave propagation in soft tissue. In this article, our previously developed wave propagation model for transluminal propagation based on a Kelvin Voigt Fractional Derivative wave equation is experimentally validated. The transluminal procedure uses the transmission and detection of shear waves through the luminal wall. The model was compared against high-speed camera observations in translucent elastography phantoms with similar viscoelastic properties to prostate tissue. An ad hoc cross-correlation procedure was used to reconstruct the angular displacement from the high-speed camera observations. Rheometry and shear wave elastography were used for characterising the shear wave velocity dispersion curve for the phantoms. Fractional viscoelastic properties were derived after fitting the dispersion curve to its analytical expression. Propagation features and amplitude spectra from simulations and high-speed camera observations were compared. The obtained results indicate that the model replicates the experimental observations with acceptable accuracy. The model presented here provides a useful tool to model transluminal procedures based on wave propagation and its interaction with the mechanical properties of the tissue outside the lumen.
分数粘弹性流变模型，如 Kelvin Voigt 分数导数模型，已在文献中被提出用于模拟软组织中的剪切波传播。在本文中，我们基于 Kelvin Voigt 分数导数波动方程，对之前开发的用于腔内传播的波传播模型进行了实验验证。腔内过程利用通过腔壁的剪切波的传输和检测。该模型与具有类似前列腺组织粘弹性特性的半透明弹性体幻影中的高速摄像机观察结果进行了比较。使用特定的互相关程序，从高速摄像机观察结果中重建角位移。流变学和剪切波弹性成像用于描述幻影的剪切波速度频散曲线。分数粘弹性特性是通过将频散曲线拟合到其解析表达式来获得的。比较了模拟和高速摄像机观察的传播特征和幅度谱。获得的结果表明，该模型以可接受的精度复制了实验观察结果。本文提出的模型为基于波传播及其与腔外组织力学特性相互作用的腔内程序提供了有用的工具。
