Service de physique médicale et de radioprotection, Centre Intégré de Cancérologie, CHU de Québec - Université Laval et Centre de recherche du CHU de Québec, Québec, Québec, Canada; Département de Physique, de Génie Physique et d'Optique et Centre de Recherche sur le Cancer, Université Laval, Québec Québec G1V 0A6, Canada.
Service de physique médicale et de radioprotection, Centre Intégré de Cancérologie, CHU de Québec - Université Laval et Centre de recherche du CHU de Québec, Québec, Québec, Canada; Département de Physique, de Génie Physique et d'Optique et Centre de Recherche sur le Cancer, Université Laval, Québec Québec G1V 0A6, Canada.
Phys Med. 2023 Mar;107:102516. doi: 10.1016/j.ejmp.2022.102516. Epub 2023 Feb 16.
This work has the purpose of validating the Monte Carlo toolkit TOol for PArticle Simulation (TOPAS) for low-dose-rate (LDR) brachytherapy uses.
Simulations of 12 LDR sources and 2 COMS eye plaques (10 mm and 20 mm in diameter) and comparisons with published reference data from the Carleton Laboratory for Radiotherapy Physics (CLRP), the TG-43 consensus data and the TG-129 consensus data were performed. Sources from the IROC Houston Source Registry were modeled. The OncoSeed 6711 and the SelectSeed 130.002 were also modeled for historical reasons. For each source, the dose rate constant, the radial dose function and the anisotropy functions at 0.5, 1 and 5 cm were extracted. For the eye plaques (loaded with I sources), dose distribution maps, dose profiles along the central axis and transverse axis were calculated.
Dose rate constants for 11 of the 12 sources are within 4% of the consensus data and within 2% of the CLRP data. The radial dose functions and anisotropy functions are mostly within 2% of the CLRP data. In average, 92% of all voxels are within 1% of the CLRP data for the eye plaques dose distributions. The dose profiles are within 0.5% (central axis) and 1% (transverse axis) of the reference data.
The TOPAS MC toolkit was validated for LDR brachytherapy applications. Single-seed and multi-seed results agree with the published reference data. TOPAS has several benefits such as a simplified approach to MC simulations and an accessible brachytherapy package including comprehensive learning resources.
本工作旨在验证用于低剂量率（LDR）近距离放射治疗的蒙特卡罗工具包 TOol for PArticle Simulation（TOPAS）。
对 12 个 LDR 源和 2 个 COMS 眼贴（直径 10mm 和 20mm）进行了模拟，并与来自 Carleton 放射治疗物理实验室（CLRP）、TG-43 共识数据和 TG-129 共识数据的已发表参考数据进行了比较。模拟了 IROC 休斯顿源注册处的源。出于历史原因，还模拟了 OncoSeed 6711 和 SelectSeed 130.002。对于每个源，提取了剂量率常数、径向剂量函数和 0.5、1 和 5cm 处的各向异性函数。对于眼贴（装载 I 源），计算了剂量分布图、中央轴和横截面上的剂量分布曲线。
12 个源中的 11 个源的剂量率常数与共识数据的偏差在 4%以内，与 CLRP 数据的偏差在 2%以内。径向剂量函数和各向异性函数与 CLRP 数据的偏差大多在 2%以内。平均而言，眼贴剂量分布中 92%的体素与 CLRP 数据的偏差在 1%以内。剂量分布曲线在参考数据的 0.5%（中央轴）和 1%（横截面上）以内。
TOPAS MC 工具包已通过 LDR 近距离放射治疗应用的验证。单种子和多种子结果与已发表的参考数据一致。TOPAS 具有简化 MC 模拟的方法和易于访问的近距离放射治疗包等优点，包括全面的学习资源。
