ABSTRACT

Our aim in this study was to evaluate two methods used in the diagnosis of renal artery stenosis (RAS): color Doppler ultrasound (CDUS), which is non-invasive and easy to use, and computerized tomography (CT)-angiography (CTA). We also evaluated the efficiency of Doppler parameters.

We included patients who were clinically diagnosed for renal-vascular disease (RVD) in our Clinic from October 2007 to May 2010 and studied them with CDUS and CTA. According to renal CTA, patients were divided into two groups as having >50% or <50% of stenosis in the renal artery (RA). We then evaluated the distal and proximal criteria of CDUS.

In total, 62 RAs were evaluated; 83.9% of them showed <50% and 16.1% showed >50% stenosis as proven by CTA. In the evaluation of CDUS criteria considering the threshold value of 180 cm/s for peak systolic venous velocity (PSV), sensitivity, specificity and positive and negative predictive values were 80%, 94.2%, 72.7%, and 96.1%, respectively. Considering Renal Aortic Ratio (RAR) threshold value of 2.5, these values were 66.6%, 94.1%, 66.6%, and 94.1%, respectively, and evaluating distal criteria together (acceleration time [AT] >120 ms and acceleration index [AI] <3 m/s²), these values were 60%, 61.5%, 23.1%, and 88.9%, respectively.

RAR and increase in peak systolic volume of the RA in CDUS showed statistical significance (p<0.01) in the diagnosis of RAS. The most successful parameter in CDUS for diagnosis of RAS is RA PSV >180 cm/sec. AT and AI have no statistical significance (p>0.05) in diagnosis of RAS. When the CDUS is inadequate, CTA is the second choice in the diagnosis of RAS.