Dastikas Rokas, Jreije Antonio, Gricienė Birutė
Faculty of Medicine, Vilnius University, Vilnius, Lithuania.
Vilnius University Hospital Santaros Klinikos, Vilnius, Lithuania.
Acta Med Litu. 2025;32(1):120-125. doi: 10.15388/Amed.2025.32.1.12. Epub 2025 Feb 18.
Computed tomography is a highly informative diagnostic tool, but its use poses the challenge of managing potentially high radiation exposure to patients. Children are particularly vulnerable to the harmful effects of ionizing radiation, and the growing use of paediatric (CT) scans has been linked to an elevated lifetime risk of cancer and an increased mortality. The aim of this study was to evaluate local radiation exposure doses in paediatric thoracic and abdominal-pelvic CT exams, to establish (DRL) curves, propose local diagnostic reference levels, and compare them with the existing literature and the European Guidelines on Diagnostic Reference Levels for Paediatric Imaging (PiDRL).
A dataset of thoracic and abdominal-pelvic CT exams performed on children was analysed. Scan data entries were grouped according to the patient weight in the following intervals: 5 to 14 kg, 15 to 29 kg, 30 to 49 kg, and 50 to 79 kg. In each weight group, the minimum, first quartile, median, third quartile, and the maximum values of (CTDI) and the (DLP) were calculated. The relationship between CTDI, DLP, and the patient body weight was assessed by using exponential curves.
The local DRLs were established for thoracic CT exams, while, for abdominal-pelvic CT exams, the DRL curve was set as a substitute due to limited data. The proposed local DRL values for thoracic computed tomography examinations are 2.0, 2.4, 3.6, and 5.0 mGy for CTDI and 40, 60, 116, and 156 mGy•cm for DLP in the corresponding weight groups of 5 to 14 kg, 15 to 29 kg, 30 to 49 kg, and 50 to 79 kg. The median values of CTDI for paediatric abdominal-pelvic computed tomography were 2.8 mGy in the 5-to-14 kg weight group, 3.6 mGy in the 15-to-29 kg group, 4.8 mGy in the 30-to-49 kg group, and 7.9 in the 50-to-79 kg group. The median DLP values were 81, 127, 203, and 304 mGy•cm, respectively.
The set local DRLs for thoracic and the median dose values in abdominal-pelvic CT exams are generally lower than the European DRLs. The derived DRL curves fulfil the same purpose as weight-group DRLs, serving as benchmarks for dose optimization.
计算机断层扫描是一种信息丰富的诊断工具，但其使用给管理患者潜在的高辐射暴露带来了挑战。儿童尤其容易受到电离辐射的有害影响，儿科计算机断层扫描（CT）的使用日益增加与终生患癌风险升高和死亡率增加有关。本研究的目的是评估儿科胸部和腹部盆腔CT检查中的局部辐射暴露剂量，建立诊断参考水平（DRL）曲线，提出局部诊断参考水平，并将其与现有文献以及欧洲儿科影像诊断参考水平指南（PiDRL）进行比较。
分析了对儿童进行的胸部和腹部盆腔CT检查的数据集。扫描数据条目根据患者体重按以下区间分组：5至14千克、15至29千克、30至49千克和50至79千克。在每个体重组中，计算了容积CT剂量指数（CTDI）和剂量长度乘积（DLP）的最小值、第一四分位数、中位数、第三四分位数和最大值。通过使用指数曲线评估CTDI、DLP与患者体重之间的关系。
为胸部CT检查建立了局部DRL，而对于腹部盆腔CT检查，由于数据有限，将DRL曲线作为替代。对于胸部计算机断层扫描检查，在相应的5至14千克、15至29千克、30至49千克和50至79千克体重组中，建议的局部CTDI诊断参考水平值分别为2.0、2.4、3.6和5.0毫西弗，DLP诊断参考水平值分别为40、60、116和156毫西弗·厘米。儿科腹部盆腔计算机断层扫描CTDI的中位数在5至14千克体重组中为2.8毫西弗，在15至29千克组中为3.6毫西弗，在30至49千克组中为4.8毫西弗，在50至79千克组中为7.9毫西弗。DLP的中位数分别为81、127、203和304毫西弗·厘米。
设定的胸部局部DRL以及腹部盆腔CT检查中的中位数剂量值通常低于欧洲的DRL。得出的DRL曲线与体重组DRL具有相同的目的，可作为剂量优化的基准。
