Objective- Analysis of the PSV (peak systolic velocity), EDV (end diastolic velocity) and RI (Resistant Index) in external ophthalmic and the long ciliary ophthalmic arteries in the cat by pulse Doppler. Design- Descriptive study Animals- 12 short haired “Tomcats” weighted about 3.9± 0.9 Kg no e general and optic disease in clinical, paraclinical and ophthalmoscopic examinations. Pr...

OBJECTIVE To compare the clinical utility of contrast-enhanced color Doppler US in the differentiation of retinal detachment (RD) from vitreous membrane (VM) with that of various conventional US modalities, and to analyze the enhancement patterns in cases showing an enhancement effect. MATERIALS AND METHODS In 32 eyes examined over a recent two-year period, RD (n=14) and VM (n=18) were confir...

INTRODUCTION Serial monitoring of patients participating in clinical trials of carotid artery therapy requires noninvasive precision methods that are inexpensive, safe and widely available. Noninvasive ultrasonic duplex Doppler velocimetry provides a precision method that can be used for recruitment qualification, pre-treatment classification and post treatment surveillance for remodeling and r...

The performance of a Doppler estimation scheme for CDMA land mobile satellite systems under realistic channel conditions is studied by computer simulation. The scheme can be applied in Doppler compensation of the received signals, to aid in the code acquisition under the severe Doppler conditions offered by the satellite channel. The proposed scheme is based on a continuous-wave pilot carrier p...

This paper studies energy and spectral efficient Doppler diversity transmissions in the presence of imperfect channel state information (CSI). Fast time-varying fading in high-mobility communication systems introduces Doppler diversity that can benefit system performance. On the other hand, it is more difficult to estimate and track fast time-varying channel; thus, channel estimation errors mig...

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 ...

OBJECTIVE To determine if colour Doppler ultrasonography can characterise the nature of intraarticular echogenic structures and synovial villi more precisely than conventional ultrasonography. METHODS This is a prospective study on 20 patients--10 with rheumatoid arthritis and 10 with osteoarthritis. Colour Doppler ultrasonography of the knee joints was performed prior to total prosthetic rep...

Doppler devices can provide clinically useful information about blood flow. This paper describes how a pulse-Doppler instrument has been linked to a B-scan machine so that flow patterns in any ultrasonically accessible vessel can be monitored from the skin surface. The same transducer is used for both modes of investigation to enable accurate and reliable positioning of the sample-volume. After...

BACKGROUND Myocardial strain is a measure of regional deformation, and by definition, negative strain means shortening and positive strain, elongation. This study investigates whether myocardial strain can be measured by Doppler echocardiography as the time integral of regional velocity gradients, using sonomicrometry as reference method. METHODS AND RESULTS In 13 anesthetized dogs, myocardia...