ANATOMY
EXTRACRANIAL HEAD AND NECK
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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False
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True
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Either A or B
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None of the above
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Detailed explanation-1: -The tardus parvus (TP) waveform is a sonographic sign frequently observed in spectral Doppler of arteries distal to a stenosis or reconstituted arteries distal to an occlusion.
Detailed explanation-2: -At Doppler US, tardus parvus pattern was defined as a waveform with a resistive index (RI) of less than 0.5 and a systolic acceleration time longer than 0.08 second.
Detailed explanation-3: -Tardus parvus is the waveform appearance in which the systolic upstroke is delayed. This waveform shape is indicative of severe, proximal, or inflow, disease.
Detailed explanation-4: -A renal/aortic ratio greater than 3.5 predicts renal artery stenosis (RAS) greater than 60% with a sensitivity of 84% to 91% and a specificity of 95% to 97%. 14 Furthermore, several levels of peak systolic velocity (PSV), ranging from 100 to 200 cm/sec, have been proposed with different accuracies.