Université de Bordeaux, Centre Lasers Intenses et Applications (UMR CNRS/CEA 5107), Talence, France.
Université de Bourgogne Franche-Comté, Laboratoire Chrono-Environnement (UMR CNRS 6249), Besançon Cedex, France.
Med Phys. 2024 Jul;51(7):5007-5019. doi: 10.1002/mp.17016. Epub 2024 Mar 13.
Monte Carlo simulations have been considered for a long time the gold standard for dose calculations in conventional radiotherapy and are currently being applied for the same purpose in innovative radiotherapy techniques such as targeted radionuclide therapy (TRT).
We present in this work a benchmarking study of the latest version of the Transport d'Ions Lourds Dans l'Aqua & Vivo (TILDA-V ) Monte Carlo track structure code, highlighting its capabilities for describing the full slowing down of -particles in water and the energy deposited in cells by -emitters in the context of TRT.
We performed radiation transport simulations of -particles (10 keV -100 MeV ) in water with TILDA-V and the Particle and Heavy Ion Transport code System (PHITS) version 3.33. We compared the predictions of each code in terms of track parameters (stopping power, range and radial dose profiles) and cellular S-values of the promising radionuclide astatine-211 ( ). Additional comparisons were made with available data in the literature.
The stopping power, range and radial dose profiles of -particles computed with TILDA-V were in excellent agreement with other calculations and available data. Overall, minor differences with PHITS were ascribed to phase effects, that is, related to the use of interaction cross sections computed for water vapor or liquid water. However, important discrepancies were observed in the radial dose profiles of monoenergetic -particles, for which PHITS results showed a large underestimation of the absorbed dose compared to other codes and experimental data. The cellular S-values of computed with TILDA-V agreed within 4% with the values predicted by PHITS and MIRDcell.
The validation of the TILDA-V code presented in this work opens the possibility to use it as an accurate simulation tool for investigating the interaction of -particles in biological media down to the nanometer scale in the context of medical research. The code may help nuclear medicine physicians in their choice of -emitters for TRT. Further research will focus on the application of TILDA-V for quantifying radioinduced damage on the deoxyribonucleic acid (DNA) molecule.
蒙特卡罗模拟长期以来一直被认为是常规放射治疗中剂量计算的金标准，目前正被应用于靶向放射性核素治疗（TRT）等创新放射治疗技术中。
本研究旨在对最新版的 Transport d'Ions Lourds Dans l'Aqua & Vivo（TILDA-V）蒙特卡罗径迹结构代码进行基准测试，突出其在描述β粒子在水中的完全减速以及β发射体在 TRT 背景下细胞内沉积能量的能力。
我们使用 TILDA-V 和粒子与重离子输运代码系统（PHITS）版本 3.33 对水中的β粒子（10keV-100MeV）进行了辐射输运模拟。我们比较了每个代码在径迹参数（阻止本领、射程和径向剂量分布）和有前途的放射性核素砹-211（ ）的细胞 S 值方面的预测结果。还与文献中的可用数据进行了额外的比较。
TILDA-V 计算的β粒子的阻止本领、射程和径向剂量分布与其他计算和可用数据非常吻合。总体而言，与 PHITS 的微小差异归因于相位效应，即与用于水蒸气或液态水的相互作用截面的使用有关。然而，在单能β粒子的径向剂量分布中观察到了重要的差异，PHITS 结果与其他代码和实验数据相比，对吸收剂量的估计明显不足。TILDA-V 计算的 的细胞 S 值与 PHITS 和 MIRDcell 预测的值相差在 4%以内。
本研究对 TILDA-V 代码的验证为在医学研究中，将其作为研究β粒子在生物介质中相互作用的精确模拟工具提供了可能性，其空间分辨率可达纳米级。该代码可能有助于核医学医师在 TRT 中选择β发射体。进一步的研究将集中在 TILDA-V 在量化 DNA 分子放射性损伤方面的应用上。
