Purpose or Case Report: Foreign body (FB) aspiration is a common medical emergency in children, which can be fatal. Prompt diagnosis is crucial to avoid complication. Bronchoscopy represents the gold standard for diagnosis; however, false negatives can lead to unnecessary invasive testing and exposes children to procedural risks. While lateral decubitus radiographs can assess for air trapping, this exam has low sensitivity for detecting airway foreign bodies. Thus, there is a need for a sensitive and specific diagnostic imaging test in the detection of airway FB. We developed and implemented a FB chest CT protocol that is characterized by low-dose relative to a standard chest CT and no intravenous contrast. We hypothesize that low-dose chest CT is a sensitive and specific modality for detection of airway FB in the pediatric population that may ultimately decrease the negative bronchoscopy rate.
Methods & Materials: The retrospective study was performed at a quaternary care children’s healthcare system in a major metropolitan city. There were 56 patients included, aged 0-18 years, who underwent low-dose chest CT and bronchoscopy for suspected FBA, between June 2022 and March 2025. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were used to evaluate the performance of low-dose chest CT compared to the gold standard. Radiation dose was an additional metric evaluated. A 95% confidence interval was calculated.
Results: A total of 56 patients were included (mean age 4.3 ± 4.3, 51.8% male). Low-dose CT was negative in 46/56 cases, with one false negative (1/46), proven positive by bronchoscopy. CT yielded positive results in 10/56 cases, which were all true positives. We observed a sensitivity of 90.9% (95% CI: 58.7-99.8), specificity of 100% (95% CI: 92.1-100), PPV of 100% (95% CI: 69.2-100), NPV of 97.8% (95% CI: 88.5-99.9), and accuracy of 98.2% (95% CI: 90.4-100). The median radiation dose with interquartile range for the exam was 0.41 [0.27 – 0.60] mSv.
Conclusions: Low-dose chest CT can accurately identify FB aspiration in children. Given its excellent specificity, NPV, and low radiation exposure, low-dose chest CT can safely rule out airway FB and may ultimately reduce unnecessary bronchoscopies in suspected airway FB evaluation.