A Bayesian 3-compartment model for 99mTc-MAG3 clearance.
Because recent reports have questioned the traditional 2-compartment model for calculating tracer clearance after a single intravenous injection, a 3-compartment model was evaluated in this study.


METHODS
Bayesian statistics were used, which facilitated curve fitting by treating all subjects simultaneously. (99m)Tc-Mercaptoacetyltriglycine clearance data from 154 adults and 109 children were measured at several centers, typically 6-9 plasma samples spanning 5-90 min, and fitted by 2- and 3-compartment Bayesian models.


RESULTS
Clearance estimates were found to be systematically lower for the 3-compartment model than for the 2-compartment model. A single-sample procedure based on the 3-compartment model was found to eliminate most of the known discrepancy between formulas based on single-injection and continuous-infusion reference methods.


CONCLUSIONS
A 3-compartment model led to lower and probably more accurate clearance estimates than the conventional 2-compartment model. A new single-sample method is presented, based on the 3-compartment model as reference standard.
Russell
Charles D
CD
Division of Nuclear Medicine, University of Alabama Hospital, 619 S. 19th Street, Birmingham, AL 35233, USA. crussell@uab.edu
D000293:Adolescent; D000328:Adult; D001499:Bayes Theorem; D002648:Child; D002675:Child, Preschool; D003198:Computer Simulation; D006801:Humans; D007223:Infant; D007668:Kidney / Q000000981:diagnostic imaging / Q000378:metabolism*; D008657:Metabolic Clearance Rate; D008954:Models, Biological; D011786:Quality Control; D011866:Radioisotope Renography / Q000379:methods; D019275:Radiopharmaceuticals / Q000097:blood / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017263:Technetium Tc 99m Mertiatide / Q000097:blood / Q000493:pharmacokinetics*
D019275:Radiopharmaceuticals; D017263:Technetium Tc 99m Mertiatide