Row-Column-Based Coherence Imaging Using a 2-D Array Transducer: A Row-Based Implementation

Abstract

Reverberations from tissues around the heart often result in cluttered echocardiograms with reduced diagnostic value. As a consequence, some patients must undergo more expensive and, in some cases, invasive imaging modalities. Coherence-based beamforming can suppress the effect of incoherent reverberations compared with the coherent signal. In some cases, these incoherent reverberations are received by only a part of the aperture. However, the coherence-based techniques, when used on a 1-D array transducer, do not take this into account. We propose an extension of coherence imaging method when using a 2-D array transducer and test a row-based implementation of this extension on two in vitro scenarios and four in vivo cases. The results show that the proposed method improves the lateral resolution compared with the (already improved) resolution with conventional coherence imaging. Furthermore, it gives up to 28% increase in generalized contrast-to-noise ratio (gCNR) (improved detection probability) when incoherent reverberations are partly received by the transducer in the elevation direction.