NORMAL RANGES OF RENAL PHYSIOLOGICAL-PARAMETERS FOR TC-99M MERCAPTOACETYLTRIGLYCINE AND THE INFLUENCE OF AGE AND SEX USING A CAMERA-BASED METHOD

162 normal Chinese men and women underwent a Tc-99m MAG3 renal study. Seventy-two males and 90 females were evaluated in 5 age groups: group 1, 61-80 years; group 2, 51-60 years; group 3, 41-50 years; group 4, 31-40 years, and group 5, 21-30 years. Each subject was required to fi t the following criteria: (I) clinically no history of renal, urinary disorders and systemic diseases, normal blood pressure, kidney morphol ogy, urinary examination and serum creatinine, and (2) for the gamma c amera study normal hydration and renal images, and no pelvic, ureteric dilatation or retention of tracer should be found. The normal range o f common physiological parameters for Tc-99m MAG3 renal studies was me asured in normal subjects. The effective renal plasma flow (ERPF, came ra-based Schlegel method), percent function in each kidney (renal inde x, RI), time of peak renal parenchymal activity (T-max) and half time of parenchymal activity following the peak (T1/2) were evaluated. The T-max and T1/2 Were determined with regions of interest over the entir e kidney. The results showed that (1) between the sexes, there were no significant differences for any parameter; (2) between the age groups , the only significant difference was a decrease in ERPF, normalized f or body surface area, with increasing age (group 1, 511.3 +/- 91.2; gr oup 2, 559.5 +/- 102.1; group 3, 577.1 +/- 79.2; group 4, 607.8 +/- 10 1.1, and group 5, 610.2 +/- 109.2), and (3) the RI, T-max and T1/2 wer e symmetrical and did not vary between the sexes or age groups (left v s. right: RI = 49.6 +/- 2.2 vs. 50.4 +/- 2.2%, T-max = 3.63 +/- 1.13 v s. 3.75 +/- 1.11 min, and T1/2 = 5.38 +/- 1.65 vs. 5.83 +/- 1.88 min). We find that(1) ERPF for Te-99m MAG3 decreases with age in normal Chi nese, which is similar to the results of Western countries, and (2) th e RI, T-max and T1/2 were symmetrical and did not vary between the sex es or age groups in normal Chinese, and are also similar to the result s of Western countries.