Establishment of Local Diagnostic Reference Levels for Pediatric Neck CT at Nine University Hospitals in South Korea.

Abstract

Objective: To establish local diagnostic reference levels (DRLs) for pediatric neck CT based on age, weight, and water-equivalent diameter (WED) across multiple university hospitals in South Korea.

Materials and methods: This retrospective study analyzed pediatric neck CT examinations from nine university hospitals, involving patients aged 0-18 years. Data were categorized by age, weight, and WED, and radiation dose metrics, including volume CT dose index (CTDI_vol) and dose length product, were recorded. Data retrieval and analysis were conducted using a commercially available dose-management system (Radimetrics, Bayer Healthcare). Local DRLs were established following the International Commission on Radiological Protection guidelines, using the 75th percentile as the reference value.

Results: A total of 1159 CT examinations were analyzed, including 169 scans from Institution 1, 132 from Institution 2, 126 from Institution 3, 129 from Institution 4, 128 from Institution 5, 105 from Institution 6, 162 from Institution 7, 127 from Institution 8, and 81 from Institution 9. Radiation dose metrics increased with age, weight, and WED, showing significant variability both within and across institutions. For patients weighing less than 10 kg, the DRL for CTDI_vol was 5.2 mGy. In the 10-19 kg group, the DRL was 5.8 mGy; in the 20-39 kg group, 7.6 mGy; in the 40-59 kg group, 11.0 mGy; and for patients weighing 60 kg or more, 16.2 mGy. DRLs for CTDI_vol by age groups were as follows: 5.3 mGy for infants under 1 year, 5.7 mGy for children aged 1-4 years, 7.6 mGy for ages 5-9 years, 11.2 mGy for ages 10-14 years, and 15.6 mGy for patients 15 years or older.

Conclusion: Local DRLs for pediatric neck CT were established based on age, weight, and WED across nine university hospitals in South Korea.