Doppler sonography in renal artery stenosis: An evaluation of intrarenal and extrarenal imaging parameters

A prospective comparison of different direct and indirect Doppler parameters with angiography was performed to determine the most useful Doppler parameters and threshold values for the detection of significant (≥60%) renal artery stenosis (RAS). The best combination of parameters was found to be the use of direct parameters of peak systolic velocity (PSV) greater than 180 or 200 cm/s and renal aortic ratio (RAR) greater than 3.0 with a sensitivity and specificity at 92% and 88%, respectively.