Anisotropy Evaluation of In Vivo Tissue Elasticity Measurement by Using Wavenumber Filtering

Abstract

Tissue elasticity measurements by an ultrasonic wave are a promising technique to qualitative diagnosis of tumor or liver diseases. The elasticity in the soft tissue can quantitatively be estimated by velocity of a shear wave propagating through the tissue. For safer and more accurate estimation of the velocity, an elasticity imaging method using continuous vibration wave excitation has been proposed. This method utilizes wave number vector analysis to individually estimate the velocity of the shear waves generated by multiple reflections. In this paper, applicability of the wave number filtering method is discussed to separate the plural shear waves through a phantom experiment. Then, an in-vivo experiment shows possibility to extract anisotropic information of muscle fiber for applying the tissue elasticity measurement.