Investigating ARFI Geometry effects on Shearwave Viscoelasticity Reconstructions

Biological tissues exhibit frequency-dependent shear wave dispersion (c(ph)(omega)) and absorption (alpha(omega)), which carries potential diagnostic value. However, the frequency content in different elastographic excitation and tracking schemes varies, presenting systematic uncertainty and biases in quantitative shear wave imaging. We propose a maximum aposteriori probability (MAP) estimator for a single track location (STL) elastography scheme to represent shearwave propagation. The estimator accommodates wavefront and rheological modeling to arrive at material property estimates for tissue mimicking phantoms. We show that a combination of cylindrical wave (CW) geometry and fractional Kelvin-Voigt rheology demonstrate consistent estimates across acquisition parameters. We report a reduction c(ph) reconstruction bias over a range of shear wave frequencies (200-800 Hz). Results are compared with an existing 2D Fourier transform-based inversion approach and group velocity as the state-of-the-art.