# A multi-institutional CT practices survey of pediatric head, chest, and abdomen-pelvis examinations

## TL;DR

This study surveys pediatric CT practices in Australia, Canada, and Norway to establish local radiation dose reference levels for safer imaging.

## Contribution

The study proposes country-specific local diagnostic reference levels for pediatric CT exams to guide dose optimization.

## Key findings

- Canadian and Norwegian CT dose levels were most similar, while Australian doses were generally lower except for older children's abdomen-pelvis exams.
- Size-specific dose estimates were significantly correlated with patient weight across all exams and countries.
- Local reference levels can serve as baselines for dose optimization and ongoing dose monitoring in pediatric CT.

## Abstract

Background: Pediatric patients are particularly vulnerable to the stochastic effects of ionizing radiation. Despite these risks, CT remains diagnostically essential in pediatric care. Diagnostic reference levels (DRLs) have been recommended as a radiation dose optimization tool to address these concerns. Purpose: This study aims to survey pediatric CT practices at different facilities in Australia, Canada, and Norway and to suggest local DRLs (LDRLs) at each facility as a baseline for future surveys. Materials and methods: Radiation dose indices, imaging, and demographic data were collected retrospectively at each facility using PACS for unenhanced CT head, contrast-enhanced chest, and contrast-enhanced abdomen-pelvis examinations in patients from 0 to 15 years of age. The LDRL values were determined for CT dose indices and size-specific dose estimate (SSDE) values. The Kruskal–Wallis test assessed the equality of populations across countries for all dosimetric quantities. Ordinary least squares regression was employed to express SSDE as a linear function of patient weight. Results: The LDRLs for Australian, Canadian, and Norwegian facilities were determined and examined for each age group. Canadian and Norwegian LDRL data were most similar, with Australian values being comparatively lower for all categories except for 11–15-year-old abdomen-pelvis examinations. The SSDE and patient weight were significantly positively correlated for each examination/country combination. Conclusion: The proposed local reference levels can provide local baselines for dose optimization and continuous dose assessment.