BACKGROUND Quantitation of valvular regurgitation remains a challenge. The accuracy of quantitative Doppler is controversial, and its ability to measure regurgitant volume is unknown; therefore, it is not widely used. METHODS AND RESULTS In 120 patients (20 without regurgitation, 19 with aortic regurgitation, and 81 with mitral regurgitation), the stroke volume through the mitral annulus and ...

Power ratios were derived from the principle of ultrasonic Doppler velocimetry to determine a ratio of the volume of vortices to the total vessel volume under the ultrasonic beam. This ratio also equals the ratio of the cross-sectional area of vortices to the vessel lumen. In vitro pulsatile flow experiments were performed in a Reynolds number range of 1,230-4,320 with axisymmetric constriction...

Background: To evaluate the role of 3D, 4D and color Doppler ultrasound (US) in the assessment of early human development. Materials and Methods: 380 women with uncomplicated early pregnancy between 5 and 14 weeks were evaluated by 3D, 4D and color Doppler US. Results: Regression analysis revealed exponential rise of the gestational sac volume with gestational age throughout the first trimester...

Using Monte Carlo simulations for a semi-infinite medium representing a skeletal muscle tissue, it is demonstrated that the zero- and first-order moments of the power spectrum for a representative pixel of a full-field laser-Doppler imager behave differently from classical laser-Doppler flowmetry. In particular, the zero-order moment has a very low sensitivity to tissue blood volume changes, an...

The rapid continuing development of 3-dimensional ultrasound imaging technologies has extended capabilities of fetal cardiac scanning beyond 2-dimensional imaging technologies and now provides a wide array of analytic possibilities. The acquisition of the 3D volume information is based on initial application of 2-dimensional imaging techniques including grey scale, Doppler, Power Doppler and B-...

Aim: Our aim was to gain an idea about testicular injury by comparing the reduced volume, which is one of indirect indicators damage in undescended testes, and evaluating microvascular blood flow superb imaging, also determine whether imaging modes could detect more detail decreased volume testes. Material methods: We compared testes via conventional Doppler color monochrome techniques with con...

A crucial role during the implementation of volume visualization is to identify the optimal transfer function, since the vital information and structure can be highlighted and revealed. The boundary of the volume is shared by respective portion of the two materials formed out of it, which causes undesirable thickening and ambiguity of the boundary explored via traditional LH (Low and High) hist...