Prospective Comparison of Ultra-Low-Dose Versus Standard-Dose Computed Tomography for Esophageal Foreign Body Detection.
The objective of this study was to verify the non-inferiority of ultra-low-dose computed tomography (ULD-CT) versus standard-dose CT (SD-CT) for esophageal foreign body (EFB) detection and to quantify dose-quality trade-offs. This prospective, randomized, blinded-reader study enrolled 180 patients (120 adults, 60 children) presenting with suspected EFB ingestion. Patients were randomized to ULD-CT (100 kV/50 mA, adaptive statistical iterative reconstruction-V 80% + deep learning image reconstruction) or SD-CT (120 kV/200 mA, filtered back projection + adaptive statistical iterative reconstruction-V 30%) groups. All patients underwent endoscopic or surgical reference-standard evaluation within 12 h of CT imaging, with 30-day follow-up for negative findings. The primary endpoint was the area under the curve (AUC); secondary endpoints included image quality metrics, radiation dose, and incidental findings. Both protocols achieved excellent diagnostic performance, with sensitivity/specificity of 97.8%/100% for ULD-CT and 98.9%/100% for SD-CT. The AUC was 0.985 for ULD-CT versus 0.991 for SD-CT (difference < non-inferiority margin). The effective dose was reduced by 63% with ULD-CT (P < 0.001). The signal-to-noise ratio decreased by 37% (P < 0.001), yet diagnostic acceptability (score ≥3) was maintained at 94.4% versus 97.8% (P = 0.070). Incidental findings were identified in 54 patients (30.0%), including 19 potentially actionable findings (10.6%) and 6 high-significance findings requiring urgent evaluation. Ultra-low-dose CT demonstrates non-inferior diagnostic accuracy compared with SD-CT for EFB detection while reducing radiation exposure by over 60%. These findings show potential for ULD-CT as a first-line modality for suspected EFBs pending multicenter validation.