Ultrafast Ultrasound Imaging Using Combined Transmissions With Cross-Coherence-Based Reconstruction

Abstract

Plane-wave-based ultrafast imaging has become the prevalent technique for non-conventional ultrasound imaging. The image quality, especially in terms of the suppression of artifacts, is generally compromised by reducing the number of transmissions for a higher frame rate. We hereby propose a new ultrafast imaging framework that reduces not only the side lobe artifacts but also the axial lobe artifacts using combined transmissions with a new coherence-based factor. The results from simulations, in vitro wire phantoms, the ex vivo porcine artery, and the in vivo porcine heart show that our proposed methodology greatly reduced the axial lobe artifact by 25±5 dB compared with coherent plane-wave compounding (CPWC), which was considered as the ultrafast imaging standard, and suppressed side lobe artifacts by 15 ± 5 dB compared with CPWC and coherent spherical-wave compounding. The reduction of artifacts in our proposed ultrafast imaging framework led to a better boundary delineation of soft tissues than CPWC.

Two-Dimensional Spatial Coherence for Ultrasonic DMAS Beamforming in Multi-Angle Plane-Wave Imaging

“…Though CPWC imaging provides a trade-off between the frame rate and the image quality, its image quality heavily depends on the number of PW transmit angles. With only a few PW transmit angles, the suppression of side-lobe clutter and axial-lobe artifacts is generally unsatisfactory, and thus leads to ghost artifact in the image [4].…”

“…In multi-angle PW imaging, it can be calculated from the output of JTR-MV beamforming in both the transmit and receive dimensions [11]. Other definitions of focusing factor include generalized coherence factor (GCF) [12], short-lag spatial coherence (SLSC) [13,14], normalized autocorrelation factor (NAF) [15], and cross-coherence factor [4]. These factors are calculated using received echoes from multi-angle PW transmissions and then applied to the final CPWC image output to suppress low-quality pixels.…”

Imaging Scheme for 3-D High-Frame-Rate Intracardiac Echography: A Simulation Study

“…First, the azimuthal beam divergence and central frequency in a range of 20 • -45 • and 5-8 MHz, respectively, are mutually optimized to provide an acceptable tradeoff among the imaging opening angle, transmit beam quality, and spatial resolution. Transmit beam quality in diverging wave imaging is known to be susceptible to the occurrence of so-called axial lobes or secondary pulses [37], [38], related to imperfect signal cancellation of 308 late-arriving element signals from arrays with pitch larger than 309 half a wavelength. Since the quality of the transmitted wave is 310 very important for our image quality, we will first investigate 311 and optimize the temporal profile of the transmitted diverging 312 wave in our simulations.…”

Adaptive Virtual Source Imaging Using the Sequence Intensity Factor: Simulation and Experimental Study

“…Zheng et al [25] proposed a signal eigenvalue factor based on eigenvalue decomposition to improve image resolution and contrast for synthetic aperture ultrasound imaging. Cross coherence factor was devised by combing plane-and spherical-wave transmissions to reduce artifact caused by sidelobes in ultrafast ultrasound imaging [26]. A normalized autocorrelation factor was proposed for coherent planewave compounding to enhance lateral resolution and contrast [27].…”