Pediatric dose assessment in common CT examination towards establishment of related regional DRL in Mazandaran, Iran

Background: Computed Tomography (CT) is main contributor of population dose from diagnostic X-ray examinations. Children are more radiosensitive than adults, thus optimization of CT examination in these patients is essential. The purpose of this study was to evaluate dose delivered to pediatric patients’ undergoing CT examination of the common examinations and also establishing local Diagnostic Reference Levels (DRLs). Materials and Methods: Questionnaires were designed for data collection at seven public hospitals and information about patient, protocol and CT system were recorded during 2013 and 2014. Dose measurement was performed in four age groups: 0-1, 1-5, 5-10 and 10-15 years old and two CT dose quantity including CTDIw   and DLP were calculated. Results: Values  of 40, 48, 59.5, 59.5 mGy; 16.9, 16.9, 17.14, 17.14 mGy; 17, 17, 17, 17 mGy; 17, 17, 19.2, 19.2 mGy in terms of CTDIw and 448, 538, 758, 758 mGy cm; 129, 129, 154, 167 mGy cm; 184, 225, 306, 315 mGy cm; 289, 408, 595, 670 mGy cm in terms of DLP as regional DRL for brain, sinus, chest, abdomen and pelvic examinations were obtained respectively. Conclusion: The variations in dose of some examination were considerable. As the role and usage of CT technology continues to expand, it is important that all practitioners adapt optimized protocols, especially for pediatrics scanning, following proposed reference levels