Forzini T, et al. - Via a retrospective, single-center study of children (aged under 16) free of the abdominal mass syndrome and severe scoliosis, the researchers assessed ureteral length (UL) as a function of the child’s age, using a contrast-enhanced computed tomography (CT) of the abdomen and pelvis, and calculated a new equation for predicting UL (and thus the optimal length of ureteral stents). The mean ULs were 9.7 and 9.91 cm on the right and left respectively before the age of 1 year; 20.10 and 21.08 cm at the age of 7; and 26.55 and 27.46 cm at the age of 16. Higher interobserver reproducibility of UL determination was observed. Therefore, the length of the double J catheter, on the basis of these results should be equal to the child’s age + 12 cm. Further, CT measurement of the UL in healthy children was reproducible and reliable for the judgment of the UL by age group. Hence, in ureteral surgery, the findings should improve the choice of the stent. The stent size suggested should be assessed during routine practice, in order to confirm the results.