Trends in Use of Advanced Imaging in Pediatric Emergency Departments, 2009-2018.

Importance: There is increased awareness of radiation risks from computed tomography (CT) in pediatric patients. In emergency departments (EDs), evidence-based guidelines, improvements in imaging technology, and availability of nonradiating modalities have potentially reduced CT use.
Objective: To evaluate changes over time and hospital variation in advanced imaging use.
Design, Setting, and Participants: This cross-sectional study assessed 26 082 062 ED visits by children younger than 18 years from the Pediatric Health Information System administrative database from January 1, 2009, through December 31, 2018.
Exposures: Imaging.
Main Outcomes and Measures: The primary outcome was the change in CT, ultrasonography, and magnetic resonance imaging (MRI) rates from January 1, 2009, to December 31, 2018. Imaging for specific diagnoses was examined using all patient-refined diagnosis related groups. Secondary outcomes were hospital admission and 3-day ED revisit rates and ED length of stay.
Results: There were a total of 26 082 062 visits by 9 868 406 children (mean [SD] age, 5.59 [5.15] years; 13 842 567 [53.1%] male; 9 273 181 [35.6%] non-Hispanic white) to 32 US pediatric EDs during the 10-year study period, with 1 or more advanced imaging studies used in 1 919 283 encounters (7.4%). The proportion of ED encounters with any advanced imaging increased from 6.4% (95% CI, 6.2%-6.2%) in 2009 to 8.7% (95% CI, 8.7%-8.8%) in 2018. The proportion of ED encounters with CT decreased from 3.9% (95% CI, 3.9%-3.9%) to 2.9% (95% CI, 2.9%-3.0%) (P < .001 for trend), with ultrasonography increased from 2.5% (95% CI, 2.5%-2.6%) to 5.8% (95% CI, 5.8%-5.9%) (P < .001 for trend), and with MRI increased from 0.3% (95% CI, 0.3%-0.4%) to 0.6% (95% CI, 0.6%-0.6%) (P < .001 for trend). The largest decreases in CT rates were for concussion (-23.0%), appendectomy (-14.9%), ventricular shunt procedures (-13.3%), and headaches (-12.4%). Factors associated with increased use of nonradiating imaging modalities included ultrasonography for abdominal pain (20.3%) and appendectomy (42.5%) and MRI for ventricular shunt procedures (17.9%) (P < .001 for trend). Across the study period, EDs varied widely in the use of ultrasonography for appendectomy (median, 57.5%; interquartile range [IQR], 40.4%-69.8%) and MRI (median, 15.8%; IQR, 8.3%-35.1%) and CT (median, 69.5%; IQR, 54.5%-76.4%) for ventricular shunt procedures. Overall, ED length of stay did not change, and hospitalization and 3-day ED revisit rates decreased during the study period.
Conclusions and Relevance: This study found that use of advanced imaging increased from 2009 to 2018. Although CT use decreased, this decrease was accompanied by a greater increase in the use of ultrasonography and MRI. There appears to be substantial variation in practice and a need to standardize imaging practices.