Abstract：
When a radiotracer is injected into a patient\'s body as part of a nuclear medicine investigation, the entire body is exposed to the ionizing radiation emitted, which can cause biological damage. Therefore, it is important to predict the internal radiation dose to properly balance the advantages of radiological examinations. Currently, various Monte Carlo tools, such as MCNP, Geant4, and GATE, are available to estimate internal radiation dosimetry-related quantities, such as S values (S) and specific absorbed fractions (SAF). Such codes make physics easier for physicists who are experienced with computer programming; however, programming and/or simulation inputs remain a time-consuming and intensive task. In this study, we present a newly developed Geant4-based code for internal dosimetry calculations, namely \"DoseCalcs\". To assess the performance of the geometrical methods and computational capabilities of our developed tool, we used the GDML, TEXT, STL, and C++ methods to model the ORNL adult phantom, and a voxel-based structure to construct the ICRP adult male. SAFs in the ORNL and ICRP adult male phantoms for eight discrete mono-energetic photons with energies ranging from 0.01 to 2 MeV are calculated with DoseCalcs and compared to ORNL and OpenDose reference data. The two phantoms showed good agreement with both references, which indicates the accuracy of DoseCalcs for subsequent use in estimating internal dosimetry quantities using a variety of geometrical methods.
摘要：
当放射性示踪剂作为核医学研究的一部分被注射到病人体内时，整个身体都暴露在发出的电离辐射中，会造成生物损害.因此,预测内部辐射剂量以适当平衡放射学检查的优势很重要。目前,各种蒙特卡洛工具，比如MCNP,Geant4和GATE,可用于估计内部辐射剂量测定相关量，如S值（S）和比吸收分数（SAF）。这些代码使物理更容易为物理学家与计算机编程的经验;然而，编程和/或仿真输入仍然是耗时且密集的任务。在这项研究中,我们提出了一个新开发的基于Geant4的内部剂量测定计算代码，即“DoseCalcs”。为了评估我们开发工具的几何方法和计算能力的性能，我们使用了GDML，文本,STL,和C++方法来模拟ORNL成人幻影，和基于体素的结构来构建ICRP成年男性。使用DoseCalcs计算了ORNL和ICRP成年男性体模中八个离散的单能光子的SAF，这些光子的能量范围为0.01至2MeV，并与ORNL和OpenDose参考数据进行了比较。这两个幻影与两个参考文献都表现出很好的一致性，这表明DoseCalcs的准确性，用于随后使用各种几何方法估计内部剂量测定量。
