[Diagnosis and visualization of renal artery stenosis by color-coded Doppler ultrasonography. Comparison of 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.