Results 221 to 230 of about 19,521 (265)

Acoustic Nonlinear Behaviour of Microbubble Contrast Agent

Chinese Physics Letters, 2002
We have investigated the nonlinear characteristics of a microbubble contrast agent Sonazoid (Nycomed, Norway), including the second, third, 1/2-order, 3/2-order and 5/2-order harmonics. We have measured the 1/2-order subharmonic response to different transmission sound pressures.
Yu Jin-Fei, Lu Rong-Rong, Gong Xiu-Fen, William T Shi   +3 more
openaire   +1 more source

Shell waves and acoustic scattering from ultrasound contrast agents

IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2001
Ultrasound contrast agents are encapsulated microbubbles, filled either with air or a higher weight molecular gas, ranging in size from 1 to 10 microns in diameter. The agents are modeled as air-filled spherical elastic shells of variable thickness and material properties.
J S, Allen, D E, Kruse, K W, Ferrara
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Image enhancement by acoustic conditioning of ultrasound contrast agents

Ultrasound in Medicine & Biology, 2004
A novel contrast imaging technique has been developed for use with microbubble contrast agents. It employs two acoustic fields: there is an excitation field for conditioning microbubbles and an imaging field for detecting microbubbles. The maximum increases (due to microbubble conditioning) in scattered first and second harmonic signals were 14.5 and ...
William T, Shi, Flemming, Forsberg, Ronald, Bautista, Chris, Vecchio, Richard, Bernardi, Barry B, Goldberg   +5 more
openaire   +2 more sources

Acoustic fields and ultrasound contrast agents

The Journal of the Acoustical Society of America, 2015
Ultrasound contrast agents are encapsulated gas bubbles which oscillate nonlinearly upon acoustic excitation. Recent developments include targeted agents for molecular imaging applications and ultrasound contrast agents such those with polymer shells specifically designed for high frequency ultrasound applications.
openaire   +1 more source

Acoustic properties of ultrasonic contrast agents

Ultrasonics, 1996
Abstract Diameters of particles used as ultrasound contrast agents are limited by capillary diameters to about 8 μm, much smaller than the acoustic wavelength used in diagnostic ultrasound. Strong acoustic backscatter from such small particles is achieved by using gas-containing particles encapsulated in a shell.
openaire   +1 more source

Simultaneous optical and acoustical observations of contrast agents

1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118), 2002
The increasing interest in the use of encapsulated microbubbles for ultrasound contrast agents and drug delivery mechanisms requires an understanding of the insonified microbubble on a microscopic scale. With the use of a video microscopy system coupled to either a microscopic ultrasound flow phantom or a chamber for insonifying stationary bubbles, the
P. Dayton, K. Morgan, M. Allietta, A. Klibanov, G. Brandenburger, K. Ferrara   +5 more
openaire   +1 more source

Magneto-photo-acoustic imaging using dual-contrast agent

2010 IEEE International Ultrasonics Symposium, 2010
Magneto-photo-acoustic imaging — a technique that integrates ultrasound, photoacoustic and magneto-motive ultrasound imaging methods, was developed. To demonstrate the feasibility of magneto-photo-acoustic imaging, the initial experiments were performed using dual-contrast agent consisting of gold nanorods and iron-oxide nanoparticles. Tissue mimicking
Min Qu, Mohammad Mehrmohammadi, Ryan Truby, Kimberly Homan, Stanislav Emelianov   +4 more
openaire   +1 more source

Optical and acoustical studies of ultrasound contrast agents

Proceedings of the IEEE 25th Annual Northeast Bioengineering Conference (Cat. No. 99CH36355), 2003
Optical and acoustical studies of ultrasound contrast agents consisting of encapsulated gas microbubbles are outlined and reviewed. Research goals include determining how the shell properties affect bubble dynamics, manipulating the transport of bubbles in blood vessels and understanding bubble destruction from the applied acoustic field.
J. Allen, P. Dayton, J. Chomas, K. Ferrara   +3 more
openaire   +1 more source

Acoustic Behavior of a Reactivated, Commercially Available Ultrasound Contrast Agent

Journal of the American Society of Echocardiography, 2017
Commercially available microbubbles such as Definity contain octafluoropropane encapsulated in a lipid shell. This perfluorocarbon can be compressed into liquid nanodroplets at room temperatures and activated with transthoracic diagnostic ultrasound.
Songita A, Choudhury, Feng, Xie, Paul A, Dayton, Thomas R, Porter   +3 more
openaire   +2 more sources

Enhanced Targeting of Ultrasound Contrast Agents Using Acoustic Radiation Force

Ultrasound in Medicine & Biology, 2007
Contrast-enhanced ultrasound has shown significant promise as a molecular imaging modality. However, one potential drawback is the difficulty that ultrasound contrast agents (UCA) may have in achieving adhesion to target molecules on the vascular endothelium. Microbubble UCA exhibit a lateral migration toward the vessel axis in laminar flow, preventing
Joshua J, Rychak, Alexander L, Klibanov, Klaus F, Ley, John A, Hossack   +3 more
openaire   +2 more sources