99mTc-DMSA absolute uptake: normal pediatric values at 2-4 hours.

OBJECTIVE This study aims to determine if normal absolute uptake values of dimercaptosuccinic acid (DMSA) can be predicted accurately over the optimal time for imaging. METHODS Eighty-eight normal kidneys were analyzed from 44 children with a median age of 4 y. The mean time between injection and scan was 171.7 min. The absolute uptake of DMSA in milligrams was calculated for each kidney. RESULTS A strong positive linear relationship was found between the absolute uptake of DMSA and the amount of DMSA injected in milligrams (corr = 0.940 [P< 0.0005]), and the age of the child (corr = 0.770 (P<0.0005)). Multiple linear regression showed that these 2 factors accounted for 92.2% of the change in absolute DMSA uptake. CONCLUSION The absolute uptake of DMSA can be accurately predicted using a linear regression equation incorporating the amount of DMSA injected in milligrams and the patient's age. Time between injection and scan appears to play little role in the absolute uptake of DMSA over 2-4 h.