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High-precision motion estimation has become essential in ultrasound-based techniques such as time-domain Doppler and elastography. Normalized cross-correlation (NCC) has been shown as one of the best motion estimators. However, a significant drawback is its associated computational cost, especially when RF signals are used. In this paper, a method based on(More)
Noninvasive quantification of regional arterial stiffness, such as measurement of the pulse wave velocity (PWV), has been shown to be of high clinical importance. Pulse wave imaging (PWI) has been previously developed by our group to visualize the propagation of the pulse wave along the aorta and to estimate the regional PWV. The objective of this paper is(More)
High frame-rate ultrasound RF data acquisition has been proved to be critical for novel cardiovascular imaging techniques, such as high-precision myocardial elastography, pulse wave imaging (PWI), and electromechanical wave imaging (EWI). To overcome the frame-rate limitations on standard clinical ultrasound systems, we developed an automated method for(More)
BACKGROUND Arterial stiffening is recognized to be associated with increased cardiovascular mortality and to be a major cause of several cardiovascular complications. Pulse wave velocity (PWV) has been widely accepted to be a reliable and robust measure of arterial stiffness. In this article, the novel ultrasound-based pulse wave imaging (PWI) method is(More)
The abdominal aortic aneurysm (AAA) is a common vascular disease. The current clinical criterion for treating AAAs is an increased diameter above a critical value. However, the maximum diameter does not correlate well with aortic rupture, the main cause of death from AAA disease. AAA disease leads to changes in the aortic wall mechanical properties. The(More)
Electromechanical Wave Imaging (EWI) is a non-invasive, ultrasound-based imaging method capable of mapping the electromechanical wave (EW) in vivo, i.e. the transient deformations occurring in response to the electrical activation of the heart. Optimal imaging frame rates, in terms of the elastographic signal-to-noise ratio, to capture the EW cannot be(More)
The Savitzky–Golay (SG) filters are generally used for smoothing and differentiation in many fields. The properties of the SG smoothing filters have been well studied. However, the properties of the SG differentiation filters or SG digital differentiators (SGDD, for the first order differentiation) are not developed well somehow, although they have been(More)
Arterial stiffness has been shown to be a good indicator of arterial wall disease. However, a single parameter is insufficient to describe the complex stress-strain relationship of a multi-component, non-linear tissue such as the aorta. We therefore propose a new approach to measure the stress-strain relationship locally in vivo noninvasively, and present a(More)
— Electromechanical imaging is a novel technique for the noninvasive mapping of electrical conduction waves in the left ventricle through the combination of ECG gating, high frame rate and RF-based displacement estimation techniques. In this paper, we identify and separate the electromechanical waves from the hemodynamically induced waves and determine the(More)
Pharmacokinetic rates have the potential to provide quantitative physiological and pathological information for biological studies and drug development. Fluorescence molecular tomography (FMT) is an attractive imaging tool for three-dimensionally resolving fluorophore distribution in small animals. In this letter, pharmacokinetic rates of indocyanine green(More)