Conventional ultrasound elastography only measures displacement in one direction and to estimate the shear wave speed, various techniques such as the phase-gradient method have been proposed. Our method utilizes lateral and axial velocities to create phase images. We used 12 directional filters to extract waves traveling in different directions. We then calculate the image autocorrelation from the directionally filtered phase images. We demonstrate that utilizing both lateral and axial displacement vector components and using the autocorrelation method in space can enhance the shear-wave velocity estimation. 2D velocity vector can be estimated using approaches like vector Doppler or transverse oscillations to be used with this method.
