[The use of ultrasonic methods for assessing renal blood flow]

A study of possibilities of different ultrasound (US) methods in the estimation of renal blood flow was made in 35 patients with angiographically documented renal artery stenosis. The validity of data obtained with US B-scanning and Doppler technique was estimated by comparison with direct artery diameter and US blood flow measurements made intraoperatively during reconstructive renal artery surgery in 25 patients. It was shown that US Doppler spectral characteristics obtained noninvasively before surgery and intraoperatively were identical. Posterior-lateral approach is optimal for Doppler examination. Differences between Doppler spectrum in the presence and absence of renal artery stenosis (RAS) were revealed. Among the RAS sensitive spectrum waveform characteristics were end-diastolic to peak systolic velocity ratios, pulsatility index, resistance parameter.