background: the recent developments in tissue doppler imaging (tdi) now more than ever permit the quantification of the myocardial function. in the current systems, tissue tracking or displacement curves are generated from color tissue doppler data through the instantaneous temporal integral of velocity-time curves. methods: the purpose of the present study was to assess regional myocardial dis...

A method for segmenting the 3D shape of curved needles in solid tissue is described. An actuator attached to the needle outside the tissue vibrates at frequencies between 600 Hz and 6500 Hz, while 3D power Doppler ultrasound imaging is applied to detect the resulting motion of the needle shaft and surrounding tissue. The cross section of the vibrating needle is detected across the series of 2D ...

The mechanical properties of the large arteries are important determinants in the circulation physiology. Quantities associated with vessel wall elasticity are of particular interest since they offer a possibility to separate diseased arteries from healthy. Pulse wave velocity (PWV) is a local measure of the arterial wall elasticity. This paper describes a new improved method for non-invasive l...

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...

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...

Polyphase is a common class of pulse compression waveforms in the radar systems. Oppermann code is one of the used codes with polyphone pattern. After compression, this code has little tolerant against Doppler shift in addition to its high side lobe level. This indicates that the use of Oppermann code is an unsuitable scheme to radars applications. This paper shows that the use of amplitude wei...

background: we sought to assess right ventricular (rv) systolic and diastolic functions via tissue doppler imaging (tdi) in order to discriminate right-to-left (bidirectional) from left-to-right intracardiac shunts. methods: a tissue doppler velocity study via doppler echocardiography was performed in 20 patients with left-to-right shunt (without evidence of significant pulmonary hypertension) ...

introduction:  in order to assess echocardiographic left ventricular functional indices in patients with differentiated thyroid carcinoma (dtc), after l-t4 withdrawal (short-term overt hypothyroidism) and during tsh suppressive therapy, we have evaluated cardiac hemodynamics in a single cohort study. methods: 24 patients with dtc were studied in two phases: 1: at least 4 weeks after l-t4 withdr...

Pulsed wave ultrasound systems can be used for determining blood's velocity non-invasively in the body. A region of interest is selected, and the received signal is range gated to measure data from the region. One complex sample value is acquired for each pulse emission after complex demodulation of the received signal. The time evolution and distribution of velocity can then be found by using ...