A comparison of pediatric and adult CT organ dose estimation methods.
A comparison of pediatric and adult CT organ dose estimation methods.
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DOI：
10.1186/s12880-017-0199-3
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发表时间：
2017-04-26
影响因子：
2.7
通讯作者：
Dauer LT
中科院分区：
文献类型：
--
作者：
Gao Y;Quinn B;Mahmood U;Long D;Erdi Y;St Germain J;Pandit-Taskar N;Xu XG;Bolch WE;Dauer LT
计算机断层扫描（CT）占美国人口医疗暴露的50%。儿童由于受照射年龄小和组织辐射敏感性增加，被认为患辐射诱发肿瘤的风险较高。器官剂量估计对于儿童和成人患者癌症风险评估至关重要。本研究的目的是通过与目前可用的儿科和成人CT器官剂量估计软件和方法进行比较，确认VirtualDose软件。五个年龄组的儿童患者和成人患者模拟三个器官剂量估计。模拟头部、胸部、骨盆-骨盆和胸腹-骨盆CT扫描，并比较扫描范围内外器官的剂量。对于成人，将VirtualDose与ImPACT和CT-Expo进行了比较。对于儿科患者，将VirtualDose与CT-Expo进行了比较，并与文献中基于尺寸的方法进行了比较。还使用VirtualDose计算了儿童与成人的有效剂量比，并与ImPACT中提供的有效剂量比范围进行了比较。剂量估计值之间的射野内器官剂量差异小于60%。对于扫描范围外的器官或分布的器官，可能会出现5倍的差异。VirtualDose与基于尺寸的方法在所研究器官的20%差异范围内一致。在VirtualDose和ImPACT之间，比较了儿童与成人的有效剂量比，胸部扫描的差异小于21%，而头颈部扫描和骨盆扫描的差异超过40%。对于儿科患者，2 cm扫描范围变化可能导致部分扫描器官的剂量差异为5倍。VirtualDose针对CT-Expo和ImPACT进行了验证，扫描范围内器官的剂量差异相对较小，而扫描范围外器官的剂量差异较大。使用基于尺寸的方法可以估计患者特定的器官剂量，并且VirtualDose与所研究器官的基于尺寸的方法一致。仔细选择CT方案的范围对于儿科和成人患者的器官剂量优化是必要的。
Computed Tomography (CT) contributes up to 50% of the medical exposure to the United States population. Children are considered to be at higher risk of developing radiation-induced tumors due to the young age of exposure and increased tissue radiosensitivity. Organ dose estimation is essential for pediatric and adult patient cancer risk assessment. The objective of this study is to validate the VirtualDose software in comparison to currently available software and methods for pediatric and adult CT organ dose estimation. Five age groups of pediatric patients and adult patients were simulated by three organ dose estimators. Head, chest, abdomen-pelvis, and chest-abdomen-pelvis CT scans were simulated, and doses to organs both inside and outside the scan range were compared. For adults, VirtualDose was compared against ImPACT and CT-Expo. For pediatric patients, VirtualDose was compared to CT-Expo and compared to size-based methods from literature. Pediatric to adult effective dose ratios were also calculated with VirtualDose, and were compared with the ranges of effective dose ratios provided in ImPACT. In-field organs see less than 60% difference in dose between dose estimators. For organs outside scan range or distributed organs, a five times’ difference can occur. VirtualDose agrees with the size-based methods within 20% difference for the organs investigated. Between VirtualDose and ImPACT, the pediatric to adult ratios for effective dose are compared, and less than 21% difference is observed for chest scan while more than 40% difference is observed for head-neck scan and abdomen-pelvis scan. For pediatric patients, 2 cm scan range change can lead to a five times dose difference in partially scanned organs. VirtualDose is validated against CT-Expo and ImPACT with relatively small discrepancies in dose for organs inside scan range, while large discrepancies in dose are observed for organs outside scan range. Patient-specific organ dose estimation is possible using the size-based methods, and VirtualDose agrees with size-based method for the organs investigated. Careful range selection for CT protocols is necessary for organ dose optimization for pediatric and adult patients.