BACKGROUND The complete continuous-wave Doppler mitral regurgitant velocity curve should allow reconstruction of the ventriculoatrial (VA) pressure gradient from mitral valve closure to opening, including left ventricular (LV) isovolumic contraction, ejection, and isovolumic relaxation. Assuming that the left atrial pressure fluctuation is relatively minor in comparison with the corresponding L...

Oculoplethysmography-carotid phonoangiography and periorbital directional Doppler sonography are two techniques widely used in the noninvasive evaluation of possible carotid artery disease. Recent advances with sonographic Doppler devices now permit measurement of blood velocities in the extracranial carotid arteries by direct scanning with a color coded Doppler imaging system. A prospective st...

Background. The complete continuous-wave Doppler mitral regurgitant velocity curve should allow reconstruction of the ventriculoatrial (VA) pressure gradient from mitral valve closure to opening, including left ventricular (LV) isovolumic contraction, ejection, and isovolumic relaxation. Assuming that the left atrial pressure fluctuation is relatively minor in comparison with the corresponding ...

This algorithm uses the GPS satellite system for navigation. It is an innovative algorithm, because it employs only the Doppler measurements and starts with a known initial location of the receiver. Initially, this algorithm was developed for fixed point GPS transmitters. In the paper we have successfully attempted to adapt this algorithm for moving satellites. This algorithm appears to perform...

We developed and assessed a real-time 3-dimensional (3D) digital Doppler method for measurement of flow volumes through the mitral valve in children. A total of 13 children (aged 10.46 +/- 2.5 years; 8 boys/5 girls) were enrolled. An ultrasound system (Sonos 7500, Philips, Andover, Mass) was used to acquire raw 3D velocity data for flow measurement based on Gaussian control surface theorem [flo...

References 1. Curry GR, White DN: Color coded ultrasonic differential velocity arterial scanner (Echoflow). Ultrasound Med Biol 4: 27-35, 1978 2. Barnes RW, Russell HE, Bone GE, Slaymaker EE: Doppler cere­ brovascular examination: Improved results with refinements in tech­ nique. Stroke 8: 468-71, 1977 3. Gee W, Mehigan JT, Wylie EJ: Measurement of collateral cerebral hemispheric blood pressure...

Conventional methods used for measuring regional renal blood flow, such as laser-Doppler flowmetry, are highly invasive, and each measurement is restricted to a discrete location. The aim of this study was to determine whether ultrasound imaging in conjunction with enhanced contrast agent (microbubbles; Vevo MicroMarker, VisualSonics) could provide a viable noninvasive alternative. This was ach...

References 1. Curry GR, White DN: Color coded ultrasonic differential velocity arterial scanner (Echoflow). Ultrasound Med Biol 4: 27-35, 1978 2. Barnes RW, Russell HE, Bone GE, Slaymaker EE: Doppler cere­ brovascular examination: Improved results with refinements in tech­ nique. Stroke 8: 468-71, 1977 3. Gee W, Mehigan JT, Wylie EJ: Measurement of collateral cerebral hemispheric blood pressure...