Shear wave speed recovery in sonoelastography using crawling wave data.
The crawling wave experiment, in which two harmonic sources oscillate at different but nearby frequencies, is a development in sonoelastography that allows real-time imaging of propagating shear wave interference patterns. Previously the crawling wave speed was recovered and used as an indicator of shear stiffness; however, it is shown in this paper that the crawling wave speed image can have artifacts that do not represent a change in stiffness. In this paper, the locations and shapes of some of the artifacts are exhibited. In addition, a differential equation is established that enables imaging of the shear wave speed, which is a quantity strongly correlated with shear stiffness change. The full algorithm is as follows: (1) extract the crawling wave phase from the spectral variance data; (2) calculate the crawling wave phase wave speed; (3) solve a first-order PDE for the phase of the wave emanating from one of the sources; and (4) compute and image the shear wave speed on a grid in the image plane.
Lin
Kui
K
Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
McLaughlin
Joyce
J
Renzi
Daniel
D
Thomas
Ashley
A
D000465:Algorithms; D016477:Artifacts; D003198:Computer Simulation; D004301:Doppler Effect; D004548:Elasticity; D054459:Elasticity Imaging Techniques; D016014:Linear Models; D009038:Motion; D009991:Oscillometry; D012815:Signal Processing, Computer-Assisted; D014465:Ultrasonics; D014732:Vibration; D014783:Viscosity