Pediatric Computed Tomography Doses in Germany from 2016 to 2018 Based on Large-Scale Data Collection.

Purpose: Accumulating evidence from epidemiological studies that pediatric computed tomography (CT) exam-inations can be associated with a small but non-zero excess risk for developing leukemia or brain tumor high-lights the need to optimize doses of pediatric CT procedures. Mandatory dose reference levels (DRL) can support reduction of collective dose from CT imaging. Regular surveys of applied dose-related parameters are instru-mental to decide when technological advances and optimized protocol design allow lower doses without sacrificing image quality. Our aim was to collect dosimetric data to support adapting current DRL to changing clinical practice.Method: Dosimetric data and technical scan parameters from common pediatric CT examinations were retro-spectively collected directly from Picture Archiving and Communication Systems (PACS), Dose Management Systems (DMS), and Radiological Information Systems (RIS).Results: We collected data from 17 institutions on 7746 CT series from the years 2016 to 2018 from examinations of the head, thorax, abdomen, cervical spine, temporal bone, paranasal sinuses and knee in patients below 18 years of age. Most of the age-stratified parameter distributions were lower than distributions from previously-analyzed data from before 2010. Most of the third quartiles were lower than German DRL at the time of the survey. Conclusions: Directly interfacing PACS, DMS, and RIS installations allows large-scale data collection but relies on high data-quality at the documentation stage. Data should be validated by expert knowledge or guided ques-tionnaires. Observed clinical practice in pediatric CT imaging suggests lowering some DRL in Germany is reasonable.