A United Sign Coherence Factor Beamformer for Coherent Plane-Wave Compounding with Improved Contrast

Chen Yang,Yiwen Xu,Yaoyao Cui,Tingyi Jiang,Yang Jiao

doi:10.3390/app10072250

Abstract

In this study, we present a united sign coherence factor beamformer for coherent plane-wave compounding (CPWC). CPWC is capable of reaching an image quality comparable to the conventional B-mode with a much higher frame rate. Conventional coherence factor (CF) based beamformers for CPWC are based on one-dimensional (1D) frameworks, either in the spatial coherence dimension or angular coherence dimension. Both 1D frameworks do not take into account the coherence information of the dimensions of each other. In order to take full advantage of the radio-frequency (RF) data, this paper proposes a united framework containing both spatial and angular information for CPWC. A united sign coherence factor beamformer (uSCF), which combines the conventional sign coherence factor (SCF) and the united framework, is introduced in the paper as well. The proposed beamformer is compared with the conventional 1D SCF beamformers (spatial and angular dimension beamformers) using simulation, phantom and in vivo studies. In the in vivo images, the proposed method improves the contrast ratio (CR) and generalized contrast-to-noise ratio (gCNR) by 197% and 20% over CPWC. Compared with other 1D methods, uSCF also shows an improved contrast and lateral resolution on all datasets.

Highlights

Medical ultrasound is a widely used clinical diagnostic method due to its convenience, safety, and real-time nature
The boundary of the artery is sharper with united sign coherence factor beamformer (uSCF), which is meaningful in a 70 dB dynamic range
The result of in vivo data proves the effectiveness and robustness of uSCF from the side. These results clearly suggest that the sign coherence factor (SCF) beamformers in coherent plane-wave compounding (CPWC) should be calculated from data before superposition among all the angles, which is in the approach of uSCF

Summary

Introduction

Medical ultrasound is a widely used clinical diagnostic method due to its convenience, safety, and real-time nature. During the past few decades, the line-per-line acquisition has become the mainstream method for clinical ultrasound imaging [1]; the frame rate is generally limited. There are some applications which require kHz frame rates to record the tissue motion [2,3] exceeding the ability of the conventional line-per-line method. Montaldo et al proposed to use several tilted-plane-wave transmissions to overcome this restriction, which is called coherent compounding [2]. Coherent plane-wave compounding (CPWC) has become a promising technique in ultrafast ultrasound imaging [2,6]

Methods

Results

Discussion

Conclusion