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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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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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On nonlinear effects in holographic-modulated ultrasound
Applied Physics Letters, 2022Holographic acoustic lenses (HALs), also known as acoustic holograms, are used for generating unprecedented complex focused ultrasound (FU) fields. HALs store the phase profile of the desired wavefront, which is used to reconstruct the acoustic pressure field when illuminated by a single acoustic source.
Ahmed Sallam, Shima Shahab
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Nonlinear and linear propagation of diagnostic ultrasound pulses
Ultrasound in Medicine & Biology, 1999The effect of nonlinear propagation in fluid followed by soft tissue was studied both theoretically and experimentally for a most crucial case in obstetrical ultrasonography. For this purpose, short pressure pulses, with the duration time of 1.3 micros and a carrier frequency of 3 MHz, radiated by a concave transducer into water, with maximum ...
L, Filipczyński +3 more
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Nonlinear viscoelastic properties of tissue assessed by ultrasound
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2006A technique to assess qualitatively the presence of higher-order viscoelastic parameters is presented. Low-frequency, monochromatic elastic waves are emitted into the material via an external vibrator. The resulting steady-state motion is detected in real time via an ultra fast ultrasound system using classical, one-dimensional (1-D) ultrasound speckle
Ralph, Sinkus +7 more
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Automatic lesions segmentation in ultrasound nonlinear imaging
IEEE International Conference on Image Processing 2005, 2005Doppler has been used for many years for cardiovascular exploration in order to visualize the vessels walls and anatomical or functional diseases. The use of ultrasound contrast agents makes it possible to improve ultrasonic information. Nonlinear ultrasound imaging highlights the detection of these agents within an organ and hence is a powerful ...
Adelaide Kissi +3 more
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Nonlinear acoustics in biomedical ultrasound
AIP Conference Proceedings, 2015Ultrasound is widely used to image inside the body; it is also used therapeutically to treat certain medical conditions. In both imaging and therapy applications the amplitudes employed in biomedical ultrasound are often high enough that nonlinear acoustic effects are present in the propagation: the effects have the potential to be advantageous in some
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Nonlinear propagation of ultrasound in superfluid3He
Journal of Statistical Physics, 1985After introducing the physics of sound propagation in normal and superfluid3He, nonlinear phenomena are discussed. These bear close resemblance to optical effects, including saturation of the absorption, amplitude dependence of the group velocity, pulse break-up, and pulse compression.
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Nonlinearities in ultrasonic flow measurement
Flow Measurement and Instrumentation, 2008Abstract The governing equations of flow acoustics including nonlinearities are solved and analyzed in terms of ultrasonic flow-measurement properties. The effect of nonlinearities for sound propagation is expected to be most significant for gas-flow measurement applications as gas-sound speeds are much smaller while fluid flows generally are much ...
Willatzen, Morten, Kamath, Hemant
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Diagnosis of osteoporosis using nonlinear ultrasound
IEEE Symposium on Ultrasonics, 2003, 2004Our aim is to diagnose osteoporosis by using nonlinear acoustics to detect microscopic cracks in human bone. We constructed a system to measure 2nd harmonic generation in human heel bone, where special care was taken to suppress 2nd harmonics generated in the electronics.
L. Hoff +3 more
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