Quantification of renal function with a count-based gamma camera method using technetium-99m-MAG3 in children.
To evaluate renal function quantitatively without blood sampling in children, renal uptake by gamma camera renography using 99mTc-MAG3 was compared with plasma clearance by a single blood sample method as the reference.


METHODS
Twenty children (15 boys, 5 girls; aged 2-14 yr) with nephrourological diseases were examined prospectively in this study. The patient received an intravenous administration of 5 MBq/kg 99mTc-MAG3 which was prepared using a commercially available kit. Gamma camera renography was performed and the renal uptake per injected dose (%RU) of the 1-min period of postinjection was calculated from a background-corrected renogram curve by computer. The plasma clearance (Clmag) of 99mTc-MAG3 was calculated by the single blood sample method at 35 min postinjection.


RESULTS
The %RU of the 1-min period in the 1-3 min postinjection correlated well with Clmag. The best correlation was observed 1-2 min postinjection. The regression equation between total %RU (X) and Clmag (Y) (ml/min/1.73 m2) was Y = -98.509 + 20.373X (r = 0.910, s = 84.19) with standardization by BSA. The best fit regression equation between individual %RU (X) and Clmag (Y) (ml/min/1.73m2) was Y = -43.799 + 19.917X (p = 0.932, s = 43.27).


CONCLUSIONS
The renal uptake method based on separate counts by gamma camera renography using 99mTc-MAG3 does not require a blood sample for quantification of renal function and may be potentially more practical in children.
Department of Nuclear Medicine, Hokkaido University School of Medicine, Sapporo, Japan.
K
K
Itoh
K
K
Nonomura
T
T
Yamashita
K
K
Kanegae
M
M
Murakumo
T
T
Koyanagi
M
M
Furudate
D000293:Adolescent; D000465:Algorithms; D002648:Child; D002675:Child, Preschool; D005069:Evaluation Studies as Topic; D005260:Female; D015902:Gamma Cameras; D006801:Humans; D007223:Infant; D008297:Male; D011446:Prospective Studies; D011866:Radioisotope Renography / Q000379:methods*; D017596:Renal Plasma Flow, Effective; D017263:Technetium Tc 99m Mertiatide; D014570:Urologic Diseases / Q000000981:diagnostic imaging*
D017263:Technetium Tc 99m Mertiatide