Evaluation of Coherence-Based Beamforming for B-Mode and Speckle Tracking Echocardiography

© 2018 IEEE. Phase coherence methods have been proposed to improve the delay-and-sum (DAS) beamforming in terms of contrast and spatial resolution. However, they could be equally beneficial for speckle tracking echocadiography, given the higher variance they introduce in the speckle texture. The aim of this study was to compare, in a close-to-clinical scenario, the B-mode and speckle tracking performance of the DAS beamformer and 4 phase coherence methods: generalized coherence factor, phase coherence factor, sign coherence factor and short lag spatial coherence. Both simulation and experimental imaging of a tissue mimicking phantom were used to assess classical imaging metrics, whereas in-vivo imaging was performed to evaluate myocardial visibility and tissue tracking. Results showed improved resolution and contrast from the coherence beamformers, as well as a reduction of clutter noise, especially in the near field. Similarly, apical strain curves were more reliably estimated following coherence processing. Overall, these methods seem to better derive both morphological and functional imaging, although no method outperformed in all scenarios.status: publishe