Viscoelastic tissue mimicking phantom validation study with shear wave elasticity imaging and viscoelastic spectroscopy

Acoustic radiation force-based shear wave elasticity (SWE) methods are used to characterize soft tissue pathologies by quantifying tissue viscoelastic (VE) properties. To adequately evaluate SWE methods measurements of VE properties, it is important to characterize VE properties of tissue mimicking phantoms with an independent method. In this study a VE tissue mimicking phantom was developed and its concentration was modified to vary the shear viscosity. Three VE phantoms were studied with SWE and hyper frequency viscoelastic spectroscopy (HFVS). The VE properties were quantified by fitting a Kelvin-Voigt fractional derivative model to the measured shear wave speed. The mean shear elasticity of the three phantoms was from 3.4 to 3.7 kPa, the mean shear viscosity was from 1.7 to 17.4 Pa•s and the power of the fractional derivative model varied from 0.6 to 0.9.