Comparison of ^<99m>Tc-MAG_3 Plasma Clearance Calculating Methods [Bubeck and Russell(1996)Methods]by Single Blood Sampling

This study was a comparison of the Bubeck and Russell(1996)methods, both of which are used to calculate ^<99m>Tc-MAG_3 plasma clearance by single blood sampling in consideration of the distribution volume of patients. Quadratic polynominal approximation showed a strong correlation between the plasma clearance values obtained by the two methods. The quantitative values obtained by the Bubeck method tended to be lower than those obtained by the Russell(1996)method in the high clearance range. However, in the low to medium clearance range(below 250 ml/min/1.73m^2), there was almost no difference between the values, and the relationship between the values obtained by the two methods could be expressed by a straight regression line. A comparison of plasma clearance values according to difference in blood sampling time(35 min and 44 min sampling)in adults showed that there was no significant change in clearance regardless of the state of renal function. Correlation of the renal uptake rate obtained by the Bubeck method using a gamma camera could be expressed by a good straight regression line that passed around the origin of the coordinates. The results showed that, although the plasma clearance values obtained by the Bubeck method tended to be underestimated in the high clearance range compared with the values obtained by the Russell(1996)method, there was a very good correlation between the values obtained by the Bubeck method and renal uptake rate.