Regional survey of pediatric patient doses from CT examinations in Tehran, Iran

Objectives: To establish regional diagnostic reference levels (RDRLs) for typical paediatric CT examinations in Tehran, Iran and compare them with established international data. In addition, the aim was to develop a method of analyzing local scan parameters for further optimization. Methods: The dose assessment was performed in terms of weighted CT dose index (CTDIw) and dose length product (DLP) for head, sinus, chest, abdomen and pelvis CT examinations using standard methods. CTDI were measured in a polymethyl methacrylate (PMMA) Head and Body phantoms. RDRLs were derived from mean survey values for different age categories in 19 CT facilities in Tehran, Iran. Results: The mean range of CTDIw for all age categories were 41.77-53.04,24.37-26.55, 12.45-13.48 and 13.18-18.25 for Brain, Sinus, Chest and Abdomen-pelvis, respectively. .Related DLPs were 325.5-495, 181.5-222.7, 143.2-250.6 and 198.5-488.4, respectively. Conclusion: Many hospitals were incorporating adult scanning parameters for children, resulting in very high effective doses. The great variations of CTDIw and DLP observed among hospitals and relatively high values of DLP in some centers are evidence that radiation doses of Paediatric patients from CT examinations need to be optimized.