Katsuta Yoshiyuki, Kadoya Noriyuki, Fujita Yukio, Shimizu Eiji, Matsunaga Kenichi, Sawada Kinya, Matsushita Haruo, Majima Kazuhiro, Jingu Keiichi
1 Department of Radiology, Takeda General Hospital, Aizuwakamatsu, Japan.
2 Department of Radiation Oncology, Tohoku University Graduate School of Medicine, Sendai, Japan.
Technol Cancer Res Treat. 2017 Dec;16(6):1220-1225. doi: 10.1177/1533034617745250. Epub 2017 Dec 5.
Log file-based methods are attracting increasing interest owing to their ability to validate volumetric-modulated arc therapy outputs with high resolution in the leaf and gantry positions and in delivered dose. Cross-validation of these methods for comparison with measurement-based methods using the ionization chamber/ArcCHECK-3DVH software (version 3.2.0) under the same conditions of treatment anatomy and plan enables an efficient evaluation of this method. In this study, with the purpose of cross-validation, we evaluate the accuracy of a log file-based method using Elekta log files and an X-ray voxel Monte Carlo dose calculation technique in the case of leaf misalignment during prostate volumetric-modulated arc therapy. In this study, 10 prostate volumetric-modulated arc therapy plans were used. Systematic multileaf collimator leaf positional errors (±0.4 and ±0.8 mm for each single bank) were deliberately introduced into the optimized plans. Then, the delivered 3-dimensional doses to a phantom with a certain patient anatomy were estimated by our system. These doses were compared with the ionization chamber dose and the ArcCHECK-3DVH dose. For the given phantom and patient anatomy, the estimated dose strongly coincided with the ionization chamber/ArcCHECK-3DVH dose ( P < .01). In addition, good agreement between the estimated dose and the ionization chamber/ArcCHECK-3DVH dose was observed. The dose estimation accuracy of our system, which combines Elekta log files and X-ray voxel Monte Carlo dose calculation, was evaluated.
基于日志文件的方法正吸引着越来越多的关注，因为它们能够在叶片和机架位置以及所输送剂量方面以高分辨率验证容积调强弧形治疗的输出。在相同的治疗解剖结构和计划条件下，使用电离室/ArcCHECK - 3DVH软件（版本3.2.0）对这些方法与基于测量的方法进行交叉验证，能够有效地评估该方法。在本研究中，为了进行交叉验证，我们评估了在前列腺容积调强弧形治疗期间叶片未对准的情况下，使用医科达日志文件和X射线体素蒙特卡罗剂量计算技术的基于日志文件的方法的准确性。在本研究中，使用了10个前列腺容积调强弧形治疗计划。将系统的多叶准直器叶片位置误差（每个单排为±0.4和±0.8毫米）故意引入优化后的计划中。然后，由我们的系统估计对具有特定患者解剖结构的模体所输送的三维剂量。将这些剂量与电离室剂量和ArcCHECK - 3DVH剂量进行比较。对于给定的模体和患者解剖结构，估计剂量与电离室/ArcCHECK - 3DVH剂量高度吻合（P <.01）。此外，观察到估计剂量与电离室/ArcCHECK - 3DVH剂量之间具有良好的一致性。评估了我们结合医科达日志文件和X射线体素蒙特卡罗剂量计算的系统的剂量估计准确性。
