Background. ACE inhibitor renal scintigraphy is widely accepted as a useful test in screening of unilateral renal artery stenosis. Another screening examination is ultrasonography, which detects haemodynamic changes with evaluation of resistive index(R I). The aim of the present study was correlation of 99mTc-DTPA captopril renography and duplexul trasound findings in diagnosis of renal artery stenosis before angiography, that is used as „gold standard“. Angiography was performed in 35 patients and their findings were correlated with scintigraphy and ultrasonography. Methods and Results. 93 patients (49 male and 44 female) aged 27 to 84 years were examined. Ultrasonography was performed in all patients with evaluation of RI. Estimation of scintigraphy was performed in accordance with interpretative criteria of 99mTc-DTPA captopril renography, which were established at the 9th Symposium of radionuclides in nefro-urology (Santa Fé 1995) and Guideline for diagnosis of renovascular hypertension (1998). 1) Agreement positive and negative findings on scintigraphy and ultrasonography were in 61/93 patients (66 %). 2) Within the group of 35 patients with angiography, the correlation between scintigraphy and ultrasonography findings was found in 27 patients (77 %). 3) When scintigraphy and angiography were correlated, the correctly diagnosed renal artery stenosis was found in 27 patients with sensitivity (77 %). 4) When sonography and angiography were correlated, the correctly sonographicaly diagnosed renal artery stenosis was found in 26 patients with sensitivity (74 %). Conclusions. On the basis of our results and according to our experience with both examinations we can conclude, that screening of unilateral renal artery stenosis with using these nonivasive methods can help to select better the indicated patients for angiography.

        Key words: stenosis of renal artery, duplexson ography, 99mTc-DTPA renal scintigraphy with Captopril test.