Kidney size estimation in Korean children with Technesium-99m dimercaptosuccinic acid scintigraphy

Purpose: Renal size is an important indicator to determine adequate organ growth in children. The aimof this study was to estimate renal size with Technesium-99m dimercaptosuccinic acid (DMSA) scanand propose a simple formula for predicting renal length in normal Korean children. Methods: This study included 346 children (148 boys and 198 girls; age range, 1 month to 17 years) inwhom renal length was measured using the DMSA scan. Patients with anatomical renal abnormalitiesor acute pyelonephritis were excluded. Children were divided into two groups: 214 children (61.8%)were less than a year old (group 1) and 132 (38.2%) were ≥1 year (group 2). Results: Renal length was larger on the left side than the right side, and there was no significantgender-related difference in renal length. We propose the following formula for renal length basedon the analysis of the 346 children in our study: the formula was as follows: 4.682×age (month)0.137,R2=0.780. In group 1, the formula was renal length (cm)=0.127×age (month)+5.144, R2=0.354, andin group 2, the formula was 0.334×age (year)+6.477, R2=0.829. Conclusion: It is difficult to establish simple formulae in infants (R2=0.354). Therefore, further studiesincluding relevant variables are needed for this age group. We proposed formulae to estimate renallength in Korean children over 1 year of age by using the DMSA scan.