Noninvasive measurement of renal function with 99mTc-MAG3 gamma-camera renography based on the one-compartment model.
OBJECTIVE
The aim of this study was to develop a method for measuring renal function with 99mTc-MAG3 gamma-camera renography without blood or urine sampling and evaluate its feasibility.


METHODS
Twelve patients with nephrological disorders underwent 99mTc-MAG3 renography and para-aminohippurate clearance measurement. Plasma clearance of 99mTc-MAG3 (ClMAG) was calculated through early renal uptake of 99mTc-MAG3 after appropriate correction of parameters (background, measured attenuation coefficient of 99mTc, and the actual depth of kidneys measured with computed tomography), and on one-compartment assumption of the kinetics of 99mTc-MAG3. We compared the resultant ClMAG with standard effective renal plasma flow (ERPF), using the para-aminohippurate clearance method and with simulated ClMAG derived from the two-compartment model.


RESULTS
ClMAG calculated by the one-compartment model (283+/-131 ml/min, mean +/- SD) correlated with ERPF (r = 0.94, p <0.001), and was similar to the simulated ClMAG estimated from the two-compartment model in all patients (283+/-139 ml/min).


CONCLUSIONS
This alternative method, which employs theoretical modeling of the pharmacokinetics of 99mTc-MAG3, may provide easy, noninvasive measurement of individual renal function without blood sampling or in vitro equipment. Further studies should be warranted.
Oriuchi
N
N
Department of Nuclear Medicine, Gunma University School of Medicine, Maebashi, Japan.
Onishi
Y
Y
Kitamura
H
H
Inoue
T
T
Tomaru
Y
Y
Higuchi
T
T
Inoue
T
T
Endo
K
K
D003198:Computer Simulation; D015902:Gamma Cameras; D006801:Humans; D007674:Kidney Diseases / Q000000981:diagnostic imaging*; D008875:Middle Aged; D011866:Radioisotope Renography / Q000379:methods / Q000706:statistics & numerical data; D019275:Radiopharmaceuticals; D017596:Renal Plasma Flow, Effective; D017263:Technetium Tc 99m Mertiatide
D019275:Radiopharmaceuticals; D017263:Technetium Tc 99m Mertiatide