Tangential sound field oscillations for 2D motion estimation in echocardiography

In this paper we present a quantitative study of a method for estimating 2D motion in echocardiography. This method is based on tangential oscillations (TO) of the sound field combined with a phase based motion estimator developed by our group. The feasibility study was presented last year at the IEEE ultrasonics symposium. Here the influence of deformation and depth of investigation are first quantitatively studied in simple simulations of a small 5 × 5 mm² square phantom displaced and deformed. RMSE study shows that the proposed method based on TO is more accurate than a conventional block matching (BM) with interpolation. A second set of more realistic simulations based on a left ventricle model during a whole cardiac cycle shows the same tendency. RMSE for TO remains beyond RMSE for BM in axial and lateral directions. The improvement goes up to 50%.