Comparative evaluation of aberration effects in crawling wave sonoelastography and comb-push ultrasound shear elastography

Various quantitative ultrasound techniques allow the estimation of elastic parameters in tissues using mechanical or acoustic radiation forces. However, it has previously been reported that the presence of phase aberration compromises elasticity measurement results when propagating in inhomogeneous media. In this study, a comparative evaluation of the effects of phase aberration when estimating shear wave speed from homogeneous and inclusion phantoms was performed using comb-push ultrasound shear elastography (CUSE) and crawling wave sonoelastography (CrW). In CUSE, acoustic radiation force induced shear wave fields are applied and in CrW, pulsed wave Doppler techniques are used to monitor the shear waves produced by mechanical vibrators. The evaluations were performed using a Verasonics ultrasound scanner and four propanediol-based aberration layers. The estimated mean shear wave speed values in the presence of aberration had maximum coefficient of variation of 37% in CrW and 96% in CUSE. The experimental results suggest that CrW outperformed CUSE in homogeneous phantoms, and both reconstructions from CUSE and CrW were adversely affected as the aberrator strength increased.