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Nonlinear intravascular ultrasound contrast imaging
Ultrasound in Medicine & Biology, 2006Nonlinear contrast agent imaging with intravascular ultrasound (IVUS) is investigated using a prototype IVUS system and an experimental small bubble contrast agent. The IVUS system employed a mechanically scanned single element transducer and was operated at a 20 MHz transmit frequency (F20) for second harmonic imaging (H40), and at a 40 MHz transmit ...
Goertz, David E. +3 more
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Nonlinear propagation in doppler ultrasound
Ultrasound in Medicine & Biology, 1993The nonlinear propagation of ultrasound was demonstrated using Doppler transducers on two commercial duplex machines. The influence of nonlinear propagation on Doppler measurements was studied on both a flow phantom and a string phantom. It was found that although the pulse waveforms showed clearly different degrees of nonlinear distortion, no effect ...
S, Li, W N, McDicken, P R, Hoskins
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The nonlinear ultrasound needle pulse
The Journal of the Acoustical Society of America, 2018Recent work has established an analytical formulation of broadband fields which extend in the axial direction and converge to a narrow concentrated line. Those unique (needle) fields have their origins in an angular spectrum configuration in which the forward propagating wavenumber of the field (kz) is constant across any z plane for all of the ...
P, Ted Christopher, Kevin J, Parker
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Ultrasound coefficient of nonlinearity imaging
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2015Imaging the acoustical coefficient of nonlinearity, β, is of interest in several healthcare interventional applications. It is an important feature that can be used for discriminating tissues. In this paper, we propose a nonlinearity characterization method with the goal of locally estimating the coefficient of nonlinearity.
Van Sloun, Ruud +3 more
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Nonlinear ultrasound simulation for heterogeneous nonlinear coefficient media
The Journal of the Acoustical Society of America, 2013In medical ultrasound, the use of simulation tools is very common to develop and test new imaging strategies. The existing tools are mainly limited to the linear propagation of ultrasound waves in tissue. A specific difficulty is due to the fact that the nonlinearity of investigated media can be different at different depths and the local value of the ...
François Varray +3 more
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Nonlinear modeling of therapeutic ultrasound
1995 IEEE Ultrasonics Symposium. Proceedings. An International Symposium, 2002The authors describe experimental finite element modeling of tissue ablation by focused ultrasound. Emphasis is on nonlinear coupling of high intensity sound temperature, and tissue properties. The numerical basis for modeling nonlinearity is an incrementally linear, time-domain, finite element algorithm solving the electromechanical and bioheat ...
G. Wojcik +4 more
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Forty years of nonlinear ultrasound
Ultrasonics, 2002Nonlinear ultrasound forms an integrated discipline of nonlinear acoustics founded in 1755. A short outline of the state-of-the-art in nonlinear ultrasound in 1960 forms the introduction to this paper. Some of the most important contributions to the development in the theoretical, analytical and numerical basis of nonlinear ultrasound and in ...
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Nonlinear acoustics in diagnostic ultrasound
Ultrasound in Medicine & Biology, 2002The propagation of ultrasonic waves is nonlinear. Phenomena associated with the propagation of diagnostic ultrasound pulses cannot be predicted using linear assumptions alone. These include a progressive distortion in waveform, the generation of frequency harmonics and acoustic shocks, excess deposition of energy and acoustic saturation.
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Nonlinear Contrast Intravascular Ultrasound
2011Intravascular ultrasound (IVUS) is an established clinical tool for assessing coronary artery atherosclerosis. Its use has contributed to an improved understanding of the natural history of atherosclerosis1 and, increasingly, IVUS data are used as an endpoint in therapeutic trials.2 For diagnostic purposes, it is employed as an adjunct to angiography ...
David E. Goertz +3 more
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Numrical Simulation of Nonlinear Focused Ultrasound
2019 14th Symposium on Piezoelectrcity, Acoustic Waves and Device Applications (SPAWDA), 2019Numerical simulation is employed to characterize the sound field of high intensity focused ultrasound, whose results agree well with the analytical results. The sound field in nonlinear case seems to be much more complicated compared with that in linear case.
De-lin WU +6 more
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