Objectives: The aim of the study was to establish normal values of NORA20 and OE20 in EC diuretic renogram for children ≤12 years of age and to compare the mean values of NORA20 and OE20 of normal renal units with that of obstructed renal units. 99m Tc – Ethylene dicysteine (EC) diuretic renogram is used to evaluate pelviureteric junction obstruction (PUJO). Commonly used parameters such as Tmax and T½, are available for semi-quantitative assessment of PUJO, but these are dependent on renal function and can be abnormal in cases with poor renal function and no obstruction. To overcome this limitation, NORA20 and OE20 were introduced as independent renal drainage parameters. However, no normal values for NORA (Normalized Residual Activity) and OE (Output Efficiency) are established for EC diuretic renogram. Material and Methods: In children equal to and below 12 years of age who underwent EC diuretic renogram in the department of Nuclear Medicine, 278 normal renal units were analyzed to establish the normal values of the parameters, and the values were compared with those obtained from 96 obstructed renal units. Results: The mean value of NORA20 was found to be 0.3577 (Standard deviation SD 0.1592), and of OE20 was found to be 92.2084 (SD 3.6717). A statistically significant difference was found between the mean values of the normal and obstructed renal units in both the parameters (P < 0.0001). Conclusion: Normal values of NORA20 and OE20 have been established in the pediatric age group for EC diuretic renogram and were found to be 0.3577 (0.1592) and 92.2084 (3.6717), respectively.
Palo et al. (Sat,) studied this question.