Correlation of 99mTc-DTPA Renal Scintigraphy with ACE Inhibitorand Duplex Ultrasound Findings in Diagnosis of Renal Artery Stenosis

Overview

Background.
ACE inhibitor renal scintigraphy is widely accepted as a useful test in screening of unilateral renalartery stenosis. Another screening examination is ultrasonography, which detects haemodynamic changes withevaluation of resistive index(R I).The aim of the present study was correlation of 99mTc-DTPA captopril renography and duplexul trasound findingsin diagnosis of renal artery stenosis before angiography, that is used as „gold standard“. Angiography was performedin 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. Ultrasonographywas performed in all patients with evaluation of RI. Estimation of scintigraphy was performed in accordance withinterpretative criteria of 99mTc-DTPA captopril renography, which were established at the 9th Symposium ofradionuclides 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 findingswas found in 27 patients (77 %). 3) When scintigraphy and angiography were correlated, the correctly diagnosedrenal artery stenosis was found in 27 patients with sensitivity (77 %). 4) When sonography and angiography werecorrelated, 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 theindicated patients for angiography.

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