Establishing diagnostic reference levels for pediatric fluoroscopic examinations in a tertiary hospital.

Abstract

Diagnostic reference levels (DRLs) identify unusually high patient radiation exposures and are required for dose optimisation. DRLs for pediatric fluoroscopic examinations are not widely determined in Australia. Our objectives were to establish DRLs for pediatric fluoroscopic examinations in a South Australian tertiary hospital and compare these to previously published data and to explore relationships between patient dose area product (DAP), age and fluoroscopy times. Dose data from 365 pediatric patients undergoing 5 fluoroscopic examinations were retrospectively collected for a 3-year period commencing January 2018 to develop local DRLs. Relationships between DAP, age and fluoroscopy time were explored using scatterplots, Spearman's correlation, and regression analyses. Local DRLs were significantly lower than data published previously, possibly reflecting technological and procedural advancements. Each 1-year increase in patient age was associated with a 0.77 μGy·m2 increase in DAP for barium meal and follow-through studies (95% confidence interval [CI]=0.055, 1.48) (P=0.04), and a 1.37 μGy·m2 increase in DAP for barium swallow studies (95% CI=0.61, 2.12) (P<0.001). A low correlation was demonstrated between DAP and fluoroscopy time for micturating cystourethrography studies (r=0.35, 95% CI=0.15, 0.51, P<0.001) and barium meal and follow-through studies (r=0.37, 95% CI= -0.011, 0.65, P=0.05). Age and fluoroscopy time were not significantly related. This study provides updated Australian pediatric fluoroscopic DRLs, with the intention of promoting a national database for benchmarking pediatric doses. The local DRLs can be used for dose comparisons and optimisation between facilities.