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Mouse models of human disease are increasingly used to study the nature of cardiovascular diseases such as atherosclerosis. The pulse wave velocity (PWV) provides an indirect measure of arterial stiffness and can be useful for characterizing disease progression. In this study, the PWV was measured noninvasively in the left common carotid artery of seven(More)
To overcome frame rate limitations in high-frequency ultrasound microimaging, new data acquisition techniques have been implemented for 2-D (B-scan) and color flow visualization. These techniques, referred to as retrospective B-scan imaging (RBI) and retrospective color flow imaging (RCFI) are based on the use of the electrocardiogram (ECG) to trigger(More)
A new approach for fabricating high frequency (> 20 MHz) linear array transducers, based on laser micromachining, has been developed. A 30 MHz, 64-element, 74-microm pitch, linear array design is presented. The performance of the device is demonstrated by comparing electrical and acoustic measurements with analytical, equivalent circuit, and finite-element(More)
In this paper, radial modulation imaging of microbubbles is investigated at high frequency. A modulation pulse frequency of 3.7 MHz with an amplitude ranging from 0 to 250 kPa, and a 1.3-MPa 20-MHz broadband imaging pulse were used. Radial modulation effects were observed on a population of flowing microbubbles and quantified using a Doppler-type processing(More)
PURPOSE The purposes of this study were to establish the physiological interpretation of the shape parameter of the dynamic contrast-enhanced ultrasound (DCE-US) lognormal perfusion model and to evaluate the clinical significance of the parameter in a sample of patients undergoing antiangiogenic therapy for metastatic renal cell carcinoma (mRCC). (More)
PURPOSE To develop and implement an evidence-based protocol for characterizing vascular response of renal cell carcinoma (RCC) to targeted therapy by using dynamic contrast material-enhanced (DCE) ultrasonography (US). MATERIALS AND METHODS The study was approved by the institutional research ethics board; written informed consent was obtained from all(More)
New medical imaging contrast agents that permit multiple imaging and therapy applications using a single agent can result in more accurate diagnosis and local treatment of diseased tissue. Solid nanoparticles (NPs) (5-150 nm in size) have emerged as promising imaging and therapy agents, as have micrometer-scale, perfluorocarbon gas-filled microbubbles (MBs)(More)
We report a single-step approach to producing small and stable bubbles functionalized with nanoparticles. The strategy includes the following events occurring in sequence: (i) a microfluidic generation of bubbles from a mixture of CO(2) and a minute amount of gases with low solubility in water, in an aqueous solution of a protein, a polysaccharide, and(More)
This work investigates the effect of ultrasound exposure parameters on the sonoporation of KHT-C cells in suspension by perflutren microbubbles. Variations in insonating acoustic pressure (0.05 to 3.5 MPa), pulse frequency (0.5 to 5.0 MHz), pulse repetition frequency (10 to 3000 Hz), pulse duration (4 to 32 micros) and insonation time (0.1 to 900 s) were(More)
Plane-wave imaging offers image acquisition rates at the pulse repetition frequency, effectively increasing the imaging frame rates by up to two orders of magnitude over conventional line-by-line imaging. This form of acquisition can be used to achieve very long ensemble lengths in nonlinear modes such as pulse inversion Doppler, which enables new imaging(More)