Measurement of viscoelastic properties of tissue-mimicking material using longitudinal wave excitation

This paper presents an experimental framework for the measurement of the viscoelastic properties of tissue-mimicking material. The novelty of the presented framework is in the use of longitudinal wave excitation and the study of the longitudinal wave patterns in finite media for the measurement of the viscoelastic properties. Ultrasound is used to track the longitudinal motions inside a test block. The viscoelastic parameters of the block are then estimated by 2 methods: a wavelength measurement method and a model fitting method. Connections are also made with shear elastography. The viscoelastic parameters are estimated for several homogeneous phantom blocks. The results from the new methods are compared with the conventional rheometry results.