Open AccessModeling of the Acoustic Field Produced by Diagnostic Ultrasound Arrays in Plane and Diverging Wave Modes
Author(s) -
Ting-Yu Lai,
Matthew Bruce,
Michalakis A. Averkiou
Publication year - 2019
Publication title -
ieee transactions on ultrasonics, ferroelectrics and frequency control/ieee transactions on ultrasonics, ferroelectrics, and frequency control
Language(s) - English
Resource type - Journals
eISSN - 1525-8955
pISSN - 0885-3010
DOI - 10.1109/tuffc.2019.2908831
Subject(s) - second harmonic imaging microscopy , ultrashort pulse , harmonic , physics , plane wave , acoustics , phased array , nonlinear system , optics , microbubbles , image quality , high harmonic generation , medical imaging , image plane , ultrasound , second harmonic generation , engineering , computer science , telecommunications , laser , quantum mechanics , artificial intelligence , antenna (radio) , image (mathematics)
Recent advances in ultrafast contrast imaging have facilitated innovations, such as superresolution imaging and ultrafast contrast-enhanced Doppler imaging. Combining plane and diverging wave imaging (PWI/DWI) with tissue harmonic imaging (THI) may offer improvements in image quality in applications such as 3-D THI and harmonic color flow. However, no studies have reported simulations of the nonlinear acoustic fields produced by diagnostic arrays in either plane or diverging wave mode. The aim of this study is to model three typical diagnostic arrays that are used in clinical practice and research, Verasonics L11-4v linear array, C5-2v convex array, and P4-2v phased array with the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation. We have two specific objectives: first, to investigate whether there is increased bubble destruction due to the nature of the plane and diverging fields in contrast imaging; and second, to investigate the feasibility of combining PWI/DWI and THI by quantifying the second harmonic generated by these fields. We showed in linear simulations that using such arrays for ultrafast contrast imaging produced pressures that are greater in the near field and lower in the far field than those of focused beams and thus may induce more near-field bubble destruction. In nonlinear simulations, the second harmonic produced by ultrafast THI was found to be 2-16 dB lower than that of focused beams for all arrays considered when operated at the same MI. This moderate difference of the second harmonic between PWI/DWI and focused ultrasound suggests that it is feasible to combine PWI/DWI and THI.