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Can ultrasound differentiate between acute and chronic deep vein thrombosis? US with color spectral Doppler imaging cannot reliably differentiate between acute and chronic DVT, because in both cases the vein is not fully compressible. However, in general, as acute thrombus ages, it reorganizes and retracts. Sonographically, this can appear as irregular wall thickening, calcified retracted …

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Normal spectral Doppler waveform in a high resistance artery Flow within arteries supplying structures with variable flow demands, such as the extremities at rest and the bowel during fasting, have higher resistance triphasic waveforms. These waveforms are characterized by narrow systolic peaks, followed by an abrupt transition between systole and diastole with transient reversal of …

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normal spectral Doppler waveform in a vein Veins typically have low-level monophasic waveforms. There can be some pulsatility of the waveform in veins closer to the heart, such as the hepatic veins. A normal vein in the extremity will also have some respiratory and cardiac waveform variability.

How is extremity deep vein thrombosis diagnosed sonographically? US is the initial imaging study of choice for evaluating suspected upper or lower extremity deep vein thrombosis (DVT). In symptomatic patients, the sensitivity and specificity of US for DVT is at least 95% and 98%, respectively. The most important sonographic feature used to diagnose DVT is …

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Normal spectral Doppler waveform in a low resistance artery Flow within arteries supplying organs that require constant perfusion include arteries to the brain, liver, and kidneys. The waveforms in these arteries will have continuous monophasic forward flow toward the organ throughout diastole. They have broad systolic peaks, gradual transition between systole and diastole, and persistent …

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How does spectral Doppler Ultrasound detect vascular stenosis? Velocity measurements in a vessel help to detect stenosis. As a vessel narrows, the velocity in the vessel increases at the point of stenosis in order to maintain the same rate of blood flow through the stenosed region. The degree of vessel stenosis correlates best with the …

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What information can be obtained from the spectral Doppler waveform of a vessel? A spectral Doppler waveform of a vessel contains both quantitative and qualitative information regarding blood flow in the interrogated vessel. Quantitative measurements include absolute velocities (peak systolic velocity (PSV), end diastolic velocity [EDV]), velocity ratios, and acceleration times. Qualitative measurements include the …

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