Factors associated with imaging modality choice in children with appendicitis

Background: The aim of this study was to evaluate a cohort of children undergoing imaging prior to appendectomy in order to identify factors that were associated with undergoing computed tomography (CT) alone as compared to ultrasound (US) alone or US and CT.

Materials and methods: The Kids' Inpatient Database was queried for children 1-18 y of age with imaging reported. Logistic regression models identified factors associated with CT-alone imaging modality.

Results: There were 6519 patients (69.5%) who underwent CT alone, 2076 (22.1%) who underwent US alone, and 782 (8.4%) who underwent US and CT. The negative appendectomy rates were higher for US alone (6.5%) and US and CT (6.6%) compared to the CT alone group (3.6%, P < 0.001). The perforated appendicitis rates were highest for the US and CT group (36.3%) compared to the CT alone group (31.8%) and the US alone group (29.8%, P = 0.004). Older patients were more likely to undergo CT alone compared to younger patients (odds ratio [OR] 1.44, 95% confidence interval [CI] 1.26-1.64). Girls were less likely to undergo CT alone compared to boys (OR 0.51, 95% CI 0.46-0.56). Hospital factors associated with lower CT-alone imaging included children's centers (OR 0.46, 95% CI 0.41-0.52), teaching hospitals (OR 0.53, 95% CI 0.48-0.60), and urban location (OR 0.40, 95% CI 0.32-0.49).

Conclusions: Though patient factors such as age and sex influence imaging use, children's centers are associated with lower CT-alone imaging compared to non-children's centers. As focus increases on limiting CT use in children, opportunities for improvement based on hospital factors exist.