Fujii K, Nomura K, Muramatsu Y, Takahashi K, Obara S, Akahane K, Satake M
Department of Radiological Sciences, Nagoya University Graduate School of Medicine, 1-1-20, Daikominami, Higashi-ku, Nagoya, Japan Department of Radiology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, Japan
Department of Radiology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, Japan.
Radiat Prot Dosimetry. 2015 Jul;165(1-4):166-71. doi: 10.1093/rpd/ncv074. Epub 2015 Apr 5.
The aim of this study was to validate the computed tomography dose index (CTDI) and organ doses evaluated by Monte Carlo simulations through comparisons with doses evaluated by in-phantom dosimetry. Organ doses were measured with radio-photoluminescence glass dosemeter (RGD) set at various organ positions within adult and 1-y-old anthropomorphic phantoms. For the dose simulations, the X-ray spectrum and bow-tie filter shape of a CT scanner were estimated and 3D voxelised data of the CTDI and anthropomorphic phantoms from the acquired CT images were derived. Organ dose simulations and measurements were performed with chest and abdomen-pelvis CT examination scan parameters. Relative differences between the simulated and measured doses were within 5 % for the volume CTDI and 13 % for organ doses for organs within the scan range in adult and paediatric CT examinations. The simulation results were considered to be in good agreement with the measured doses.
本研究的目的是通过与体模内剂量测定法评估的剂量进行比较，验证蒙特卡罗模拟评估的计算机断层扫描剂量指数（CTDI）和器官剂量。使用放射性光致发光玻璃剂量计（RGD）在成人和1岁拟人化体模内的不同器官位置测量器官剂量。对于剂量模拟，估计了CT扫描仪的X射线光谱和蝴蝶结滤波器形状，并从获取的CT图像中导出了CTDI和拟人化体模的3D体素数据。使用胸部和腹部-骨盆CT检查扫描参数进行器官剂量模拟和测量。在成人和儿科CT检查中，扫描范围内器官的体积CTDI模拟剂量与测量剂量之间的相对差异在5%以内，器官剂量相对差异在13%以内。模拟结果与测量剂量被认为具有良好的一致性。
