2D complex shear modulus imaging in Gaussian noise

Abstract

Dynamic shear-wave estimation of complex shear modulus (CSM) has demonstrated the ability to detect tumors. Ultrasound shear wave imaging is one of the methods for quantitatively estimating relevant elasticity parameters of tissues via the wave number and propagation attenuation of ultrasound waves. Maximum Likelihood Ensemble Filter (MLEF) has been efficiently applied for estimating the CSM parameters, but limited to one-dimensional (1D) scenario. This paper extends this method to detecting two-dimensional (2D) objects affected by Gaussian noise during the Doppler acquisition. A ray scanning method is used for modeling the propagation directions (lines) along each of which the MLEF is used for estimating the CSM parameters. The object 2D image is then reconstructed by transforming these estimated CSM parameters from the polar coordinates to Cartesian coordinates. it is not necessary to increase the ensemble size (which means an increase in the algorithm complexity) when the noise level is low.