@article{jing_li_gu_zhong_yao_2023, title={Time-resolved passive cavitation mapping using the transient angular spectrum approach}, volume={153}, ISSN={["1520-8524"]}, DOI={10.1121/10.0018806}, abstractNote={Passive cavitation mapping (PCM), which generates images using bubble acoustic emission signals, has been increasingly used for monitoring and guiding focused ultrasound surgery. This study investigates a transient angular spectrum (AS) approach for PCM. The working principle of this approach is to backpropagate the received signal to the domain of interest and reconstruct the spatial–temporal wavefield encoded with the bubble location and collapse time. The transient AS approach is validated using an in silico model, water bath, and in vivo experiments. It is found that the transient AS approach yields similar results to delay and sum, but is considerably faster. The results obtained by this study suggest that the transient AS approach is promising for fast and accurate PCM.}, number={3}, journal={JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA}, author={Jing, Yun and Li, Mucong and Gu, Juanjuan and Zhong, Pei and Yao, Junjie}, year={2023}, month={Mar} }
 @article{li_gu_vu_sankin_zhong_yao_jing_2021, title={Time-Resolved Passive Cavitation Mapping Using the Transient Angular Spectrum Approach}, volume={68}, ISSN={["1525-8955"]}, DOI={10.1109/TUFFC.2021.3062357}, abstractNote={Passive cavitation mapping (PCM), which generates images using bubble acoustic emission signals, has been increasingly used for monitoring and guiding focused ultrasound surgery (FUS). PCM can be used as an adjunct to magnetic resonance imaging to provide crucial information on the safety and efficacy of FUS. The most widely used algorithm for PCM is delay-and-sum (DAS). One of the major limitations of DAS is its suboptimal computational efficiency. Although frequency-domain DAS can partially resolve this issue, such an algorithm is not suitable for imaging the evolution of bubble activity in real time and for cases in which cavitation events occur asynchronously. This study investigates a transient angular spectrum (AS) approach for PCM. The working principle of this approach is to backpropagate the received signal to the domain of interest and reconstruct the spatial–temporal wavefield encoded with the bubble location and collapse time. The transient AS approach is validated using an in silico model and water bath experiments. It is found that the transient AS approach yields similar results to DAS, but it is one order of magnitude faster. The results obtained by this study suggest that the transient AS approach is promising for fast and accurate PCM.}, number={7}, journal={IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL}, author={Li, Mucong and Gu, Juanjuan and Vu, Tri and Sankin, Georgy and Zhong, Pei and Yao, Junjie and Jing, Yun}, year={2021}, month={Jul}, pages={2361–2369} }
 @article{gu_jing_2021, title={mSOUND: An Open Source Toolbox for Modeling Acoustic Wave Propagation in Heterogeneous Media}, volume={68}, ISSN={["1525-8955"]}, DOI={10.1109/TUFFC.2021.3051729}, abstractNote={mSOUND is an open-source toolbox written in MATLAB. This toolbox is intended for modeling linear/ nonlinear acoustic wave propagation in media (primarily biological tissues) with arbitrary heterogeneities, in which, the speed of sound, density, attenuation coefficient, power-law exponent, and nonlinear coefficient are all spatially varying functions. The computational model is an iterative one-way model based on a mixed domain method. In this article, a general guideline is given along with three representative examples to illustrate how to set up simulations using mSOUND. The first example uses the transient mixed-domain method (TMDM) forward projection to compute the transient acoustic field for a given source defined on a plane. The second example uses the frequency-specific mixed-domain method (FSMDM) forward projection to rapidly obtain the pressure distribution directly at the frequencies of interest, assuming linear or weakly nonlinear wave propagation. The third example demonstrates how to use TMDM backward projection to reconstruct the initial acoustic pressure field to facilitate photoacoustic tomography (PAT). mSOUND (https://m-sound.github.io/mSOUND/home) is designed to be complementary to existing ultrasound modeling toolboxes and is expected to be useful for a wide range of applications in medical ultrasound including treatment planning, PAT, transducer design, and characterization.}, number={5}, journal={IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL}, author={Gu, Juanjuan and Jing, Yun}, year={2021}, month={May}, pages={1476–1486} }
 @article{gu_jing_2021, title={mSOUND: An Open Source Toolbox for Modeling Acoustic Wave Propagation in Heterogeneous Media (vol 68, pg 1476, 2021)}, volume={68}, ISSN={["1525-8955"]}, DOI={10.1109/TUFFC.2021.3091311}, abstractNote={In the above article <xref ref-type="bibr" rid="ref1">[1]</xref>, the authors regret that there were some mistakes pertaining to <xref rid="deqn1" ref-type="disp-formula">(1)</xref> –<xref rid="deqn2" ref-type="disp-formula"/><xref rid="deqn3" ref-type="disp-formula">(3)</xref> and <xref rid="deqn5" ref-type="disp-formula">(5)</xref>.}, number={10}, journal={IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL}, author={Gu, Juanjuan and Jing, Yun}, year={2021}, month={Oct}, pages={3257–3257} }
 @article{gu_jing_2020, title={A modified mixed domain method for modeling acoustic wave propagation in strongly heterogeneous media}, volume={147}, ISSN={["1520-8524"]}, DOI={10.1121/10.0001454}, abstractNote={In this paper, phase correction and amplitude compensation are introduced to a previously developed mixed domain method (MDM), which is only accurate for modeling wave propagation in weakly heterogeneous media. Multiple reflections are also incorporated with the one-way model to improve the accuracy. The resulting model is denoted as the modified mixed domain method (MMDM) and is numerically evaluated for its accuracy and efficiency using four distinct cases. It is found that the MMDM is significantly more accurate than the MDM for strongly heterogeneous media, especially when the phase aberrating layer is approximately perpendicular to the acoustic beam. Additionally, a convergence study suggests that the second-order reflection could be sufficient for cases involving high contrast inhomogeneities and large loss values (e.g., skulls). The method developed in this work could facilitate therapeutic ultrasound for treating brain-related diseases and disorders.}, number={6}, journal={JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA}, author={Gu, Juanjuan and Jing, Yun}, year={2020}, month={Jun}, pages={4055–4068} }
 @article{suo_govind_gu_dayton_jing_2019, title={Dynamic assessment of dual-frequency microbubble-mediated sonothrombolysis in vitro}, volume={125}, ISSN={["1089-7550"]}, DOI={10.1063/1.5083908}, abstractNote={Optimizing the use of high intensity focused ultrasound (HIFU) for recanalization of occluded blood vessels is an actively researched area. This yields an alternative therapy to the use of thrombolytic drugs in the treatment of ischemic stroke. HIFU treatment, used in conjunction with microbubbles (MBs) in the fluid stream, serves to augment the dissipation of the blood clot. In this study, using an in vitro approach, we implement a flow system to simulate the dynamic dispersion of blood clots using single-frequency focused ultrasound (SFFU) and dual-frequency focused ultrasound (DFFU). The effects of permutations of acoustic power and driving frequency (SFFU vs. DFFU) on the rate of disintegration and site-specific lytic action are quantified under the influence of fluid akin to that in a blood vessel, for specific microbubble concentrations. It is found that dual-frequency excitation in general produces a faster rate of clot dissipation in comparison to single-frequency excitation, and this observation is corroborated by cavitation signal detection. Our observations indicate that accelerated thrombolysis may be realized by the inertial cavitation threshold of DFFU being lower than that of SFFU. Furthermore, the thrombolytic effect with variance in microbubble concentration is studied for a fixed acoustic power. The efficacy of DFFU is not found to vary appreciably with an increase in microbubble concentration from 108 MBs/ml to 109 MBs/ml, possibly due to acoustic shadowing induced at increased concentrations.}, number={8}, journal={JOURNAL OF APPLIED PHYSICS}, author={Suo, Dingjie and Govind, Bala and Gu, Juanjuan and Dayton, Paul A. and Jing, Yun}, year={2019}, month={Feb} }
 @article{gu_jing_2019, title={Simulation of the Second-Harmonic Ultrasound Field in Heterogeneous Soft Tissue Using a Mixed-Domain Method}, volume={66}, ISSN={["1525-8955"]}, DOI={10.1109/TUFFC.2019.2892753}, abstractNote={A mixed-domain method (MDM) dubbed frequency-specific MDM (FSMDM) is introduced for the simulation of the second-harmonic ultrasound field in weakly heterogeneous media. The governing equation for the second harmonics is derived based on the quasi-linear theory. The speed of sound, nonlinear coefficient, and attenuation coefficient are all spatially varying functions in the equation. The fundamental frequency pressure field is first solved by the FSMDM and it is subsequently used as the source term for the second-harmonics equation. This equation can be again solved by the FSMDM to rapidly obtain the second-harmonic pressure field. Five 2-D cases, including one with a realistic human tissue map, are studied to systematically verify the proposed method. Results from the previously developed transient MDM are used as the benchmark solutions. Comparisons show that the two methods give similar results for all cases. More importantly, the FSMDM has a crucial advantage over the transient MDM in that it can be two orders of magnitude faster.}, number={4}, journal={IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL}, author={Gu, Juanjuan and Jing, Yun}, year={2019}, month={Apr}, pages={669–675} }
 @article{gu_jing_2015, title={Modeling of Wave Propagation for Medical Ultrasound: A Review}, volume={62}, ISSN={["1525-8955"]}, DOI={10.1109/tuffc.2015.007034}, abstractNote={Numerical modeling of medical ultrasound has advanced tremendously in the past two decades. This opens up a great number of opportunities for medical ultrasound and associated technologies. Numerous new governing equations and algorithms have emerged and been applied to studying various medical ultrasound applications, including ultrasound imaging, photo-acoustic imaging, and therapeutic ultrasound. In addition, thanks to the rapid development of computers, modeling acoustic wave propagation in three-dimensional, large-scale domains has become a reality. This article will provide an indepth literature and technical review of recent progress on numerical modeling of medical ultrasound. Future challenges will also be discussed.}, number={11}, journal={IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL}, author={Gu, Juanjuan and Jing, Yun}, year={2015}, month={Nov}, pages={1979–1993} }