Coherent Plane-Wave Compounding Based on United Coherence Factor

Abstract

We present a united coherence factor beamformer for coherent plane-wave compounding (CPWC). CPWC is capable to reach an image quality comparable to the conventional B-mode imaging with a much higher frame rate and could be further applied to Doppler imaging. Conventional coherence factor (CF) based beamformers for CPWC use only either the spatial coherence or angular coherence information, which limits the image quality. To take full advantage of the radio frequency (RF) data for better image quality, this paper proposes a united coherence factor (uCF) using both spatial and angular information for CPWC. The proposed uCF is applied to simulated, phantom and in vivo imaging data. We evaluate the performance of the proposed method by lateral resolution and contrast. For simulated images, the contrast ratio (CR) improvements are over 80%. In the phantom images, the maximum improvements of the lateral full width at half maximum (FWHM) and CR are 10% and 105%, respectively. To compare the most core differences, the spatial and angular methods are also presented in this paper. uCF is superior in lateral resolution improvement and contrast among the beamformers. In addition, the proposed uCF performance also shows good performance in the power Doppler experiment with improved image quality, which is further verified by the spatial similarity matrix of the Doppler image. Thus, the proposed method (uCF) has a great potential to be applied in CPWC for image quality improvement.