Diagnosis and visualization of renal artery stenosis with color-coded duplex sonography comparison between central and peripheral flow patterns.

Purpose: Comparison between central and peripheral flow patterns with color-coded duplex sonography in the diagnosis of renal artery stenosis. Materials and methods: In a prospective study with sixty-six patients systolic velocity (central examination) and acceleration index (peripheral examination) were determined using color-coded duplex sonography examination in order to detect and visualize renal artery stenosis. If the central and peripheral measurements were negative, no angiography was performed. in contrast, if one of the methods yielded a pathological finding, catheter angiography was performed to verify the results (21 patients), as well as in two other unclear cases. Results: An agreement between central and peripheral measuring was seen in 49 of 66 patients. In ten patients central and peripheral measurements showed different results. In seven cases the peripheral measurements were not clear. Compared to angiography, peripheral measurement showed a sensitivity of 60 %, a specificity of 75% and a positive predictive Value of 81.8%. In contrast, central examination had a sensitivity of 100 %, a specificity of 75% and a positive predictive value of 88.2%. Conclusions: Based on our preliminary results, the measurement of the systolic velocity peak seems to be an effective method to detect renal artery stenosis.