Evaluation of a material parameter extraction algorithm using MRI-based displacement measurement

The performance of an inversion algorithm is investigated when applied to m easured displacement data for a determination of the material parameters la mbda +2 mu/rho (longitudinal wave velocity squared) and mu/rho (shear wave velocity squared) throughout an inhomogeneous test phantom. The vector disp lacement components throughout a test phantom subject to monochromatic shea r excitation measured in time using magnetic resonance imaging (MRI) were t emporally Fourier transformed to extract the component of monochromatic exc itation, and the data was delivered to the inversion algorithm. A series of inversions is presented demonstrating the effects of subsequent wavenumber filtering, polarization selection, and variation in the size of the increm ental volume elements. The resulting performance is assessed, and recommend ations for future efforts are discussed.