[Intrarenal duplex sonography in detecting flow changes after renal PTA].

PURPOSE

Changes of the intrarenal Doppler signal were analysed before and after renal balloon dilatation to assess the technical success of PTRA.

MATERIALS AND METHOD

In 33 patients, intrarenal Doppler signal was depicted before and after renal PTA. Doppler flow curve was analysed by using the acceleration index (AI), acceleration time index (AT) and resistance index (RI); for all indices side ratios (AI-R, AT-R and RI-R) were calculated. Balloon dilatation was angiographically successful in all cases. Average stenosis graded 71% before and 21% after PTA.

RESULTS

By definition of limits for all indices used, a single patient was graded as non-stenotic before balloon dilatation by application of AI/AI-R and no patient was graded nonstenotic by AI/RI-R. After renal PTA, all indices significantly changed towards normal findings and by application of both AI/AI-R and AI/RI-R, only a single patient was graded stenotic after PTA.

CONCLUSION

Intrarenal Doppler signal analysis reliably allows to detect flow changes following renal PTA in patients with renal artery stenosis. It may therefore be used as a noninvasive method to monitor flow improvement after renal PTA and during follow-up.