Motion decorrelation in echocardiography: Analysis from a realistic simulation

Echocardiography has been widely used to perform motion estimation in real time for heart function analysis. However, this imaging modality may induce a decorrelation between the real tissue motion and its ultrasonic speckle in the corresponding echocardiographic images. Most of the studies that investigate this problem are based on the assumption of a spatially invariant point spread function (PSF) which represents an oversimplification of the echographic acquisition process. Moreover, these studies use linear scanning which is not realistic in the context of echocardiography where the acquisitions are performed using sectorial probes. In this paper, we thus study the influence of echocardiographic equipment and acquisition geometry on the apparent motion through a realistic simulations using Field II. Contrary to the results obtained from an invariant PSF assumption, we show that decorrelation appears even in the case of a simple axial translation. Axial deformation is also studied and we show that the amount of decorrelation depends on the geometry of the probe.