We present herein 4D ultrafast ultrasound flow imaging, a novel ultrasound-based volumetric imaging technique for the quantitative mapping of blood flow. Complete volumetric blood flow distribution imaging was achieved through 2D tilted plane-wave insonification, 2D multi-angle cross-beam beamforming, and 3D vector Doppler velocity components estimation by least-squares fitting. 4D ultrafast ul...

In this paper we study the B-mode/Doppler duplex imaging problem. We begin by looking at the problem of determining the true velocity vector only. We develop a model for the power spectrum of a signal reeected by a line of point scatterers with a Poisson distribution. We show that with circularly symmetric apertures it is possible to use the expression of that power spectrum to determine the tr...

BACKGROUND Myocardial strain imaging using echocardiography can be a cost-effective method to quantify ventricular wall motion objectively, but few studies have compared strain measured with echocardiography against magnetic resonance imaging (MRI) in small animals. METHODS AND RESULTS We compared circumferential strain (CS) and radial strain (RS) measured with echocardiography (velocity vect...

n this issue of the Journal, Tugcu et al1 report that by using velocity vector imaging (VVI), as well as tissue Doppler imaging (TDI), subclinical regional right ventricular (RV) dysfunction is diagnosed in patients with obstructive sleep apnea (OSA) who do not have systemic or pulmonary arterial hypertension. They found that the VVIderived RV peak systolic myocardial velocity, strain/strain ra...

An integrated circuit that computes the velocity vector of a visual stimulus in one dimension is presented. The circuit combines optical sensors and associated electronics on a single silicon chip, processed with standard CMOS technology. The velocity is inferred from the time delay of the appearance of an image feature at two xed locations on the chip. The circuit operates quite robustly for h...

the six-degree equations of flight in their classic form do not provide a proper physical perception due to a number of interferences. nor do they render visible the important role of attack angles. in this study, attempts have been made to develop a complete set of 3d acceleration equations from the equations of normal and tangential acceleration αn=vωv, αt=v ̇. for this purpose, a coordinate s...

Ultrasound vibro-acoustography is a novel medical imaging modality that combines the high resolution of high-frequency ultrasound with the speckle-free images obtained using lowfrequency methods. This imaging modality relies on the nonlinear interaction of two high frequency beams at slightly different frequencies. We describe the physics of ultrasound vibroacoustography and outline a strategy ...