The impact of aberration on high frame rate cardiac B-mode imaging

In echocardiography, especially in 3D echocardiography, achieving high frame rates is a major challenge. A suggested solution is parallel receive beamforming. Without any compensation, this approach is known to produce block-like artifacts, where each block corresponds to one parallel receive group. In this work, in vitro imaging, in vivo imaging, and simulations were used to investigate the artifacts. In vitro, imaging a tissue phantom, the artifacts were successfully compensated for. However, in vivo, imaging the heart, the compensation techniques no longer sufficed and the artifacts persisted. With in vivo imaging, aberrating tissue layers are present between the heart and the probe. To investigate the effects of aberration on a parallel receive system, an in vitro experiment was performed with and without a silicon phase aberrator in front of the probe. The aberrator caused the artifacts to appear even when compensation techniques were applied. Simulations confirmed the measured results and indicated that distorted beam profiles and decorrelation between parallel receive groups caused the artifacts. To quantify the magnitude of the artifacts, a correlation-based indicator was developed. The indicator separated images with and without artifacts and confirmed that the artifacts appeared from the combination of parallel receive beams and aberration.