TC-99M-MAG3 RENAL-FUNCTION SCINTIGRAPHY A ND CAPTOPRIL IN THE DIAGNOSIS OF RENOVASCULAR HYPERTENSION

In this study, the diagnostic value of renal function scintigraphy per formed both without and with ACE inhibition has been evaluated using t he new radio-pharmaceutical Tc-99m-MAG3. In cases of decompensated ren al artery stenoses, the typical scan finding with this tubular excrete d agent was shown to be a distinct parenchymal nuclide retention in co mbination with a delayed appearance of the radiotracer in the pelvic s ystem. Using this criterion in 43 patients with suspected renovascular hypertension, sensitivity and specificity were 89 and 88 %, respectiv ely. Bilateral positive findings were non-specific; excluding them fro m the study, specificity increased to 100 %. In renal insufficiency, c aptopril scans seem to be of reduced diagnostic value. Summarising our experiences, renal function scintigraphy using Tc-99m-MAG3 without an d with captopril was proved to be a reliable non-invasive method to de tect or exclude haemodynamically relevant renal artery stenosis.