调强放射治疗计划的调制程度评估。
Assessment of the modulation degrees of intensity-modulated radiation therapy plans.
机构信息
Department of Radiation Oncology, Veterans Health Service Medical Center, Seoul, Republic of Korea.
Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Republic of Korea.
出版信息
Radiat Oncol. 2018 Dec 13;13(1):244. doi: 10.1186/s13014-018-1193-9.
BACKGROUND
To evaluate the modulation indices (MIs) for predicting the plan delivery accuracies of intensity-modulated radiation therapy (IMRT) plans.
METHODS
A total of 100 dynamic IMRT plans that used TrueBeam STx and 102 dynamic IMRT plans that used Trilogy were selected. For each plan, various MIs were calculated, which included the modulation complexity score (MCS), plan-averaged beam area (PA), plan-averaged beam irregularity (PI), plan-averaged beam modulation (PM), MI quantifying multi-leaf collimator (MLC) speeds (MI), MI quantifying MLC acceleration (MI), and MI quantifying MLC acceleration and segment aperture irregularity (MI). To determine plan delivery accuracy, global gamma passing rates, MLC errors of log files, and dose-volumetric parameter differences between original and log file-reconstructed IMRT plans were obtained. To assess the ability of each MI for predicting plan delivery accuracy, Spearman's rank correlation coefficients (r) between MIs and plan delivery accuracy measures were calculated.
RESULTS
PI showed moderately strong correlations with gamma passing rates in MapCHECK2 measurements of both TrueBeam STx and Trilogy (r = - 0.591 with p < 0.001 and - 0.427 with p < 0.001 to with gamma criterion of 2%/2 mm, respectively). For ArcCHECK measurements, PI also showed moderately strong correlations with the gamma passing rates in the ArcCHECK measurements of TrueBeam STx and Trilogy (r = - 0.545 with p < 0.001 and r = - 0.581 with p < 0.001 with gamma criterion of 2%/2 mm, respectively). The PI showed the second strongest correlation with MLC errors in both TrueBeam STx and Trilogy (r = 0.861 with p < 0.001 and r = 0.767 with p < 0.001, respectively). In general, the PI showed moderately strong correlations with every plan delivery accuracy measure.
CONCLUSIONS
The PI showed moderately strong correlations with every plan delivery accuracy measure and therefore is a useful predictor of IMRT delivery accuracy.
背景
评估调制指数（MI）以预测调强放射治疗（IMRT）计划的计划交付精度。
方法
选择了 100 个使用 TrueBeam STx 的动态 IMRT 计划和 102 个使用 Trilogy 的动态 IMRT 计划。对于每个计划，计算了各种 MI，包括调制复杂度评分（MCS）、计划平均射束面积（PA）、计划平均射束不规则性（PI）、计划平均射束调制（PM）、量化多叶准直器（MLC）速度的 MI（MI）、量化 MLC 加速度的 MI（MI）以及量化 MLC 加速度和分段孔径不规则性的 MI（MI）。为了确定计划交付精度，获得了全局伽马通过率、日志文件中的 MLC 误差以及原始和日志文件重建的 IMRT 计划之间的剂量体积参数差异。为了评估每个 MI 预测计划交付精度的能力，计算了 MI 与计划交付精度测量值之间的 Spearman 等级相关系数（r）。
结果
PI 与 TrueBeam STx 和 Trilogy 的 MapCHECK2 测量中的伽马通过率呈中度强相关（分别与伽马标准为 2%/2 mm 的 r = -0.591（p < 0.001）和 r = -0.427（p < 0.001））。对于 ArcCHECK 测量，PI 与 TrueBeam STx 和 Trilogy 的 ArcCHECK 测量中的伽马通过率也呈中度强相关（分别与伽马标准为 2%/2 mm 的 r = -0.545（p < 0.001）和 r = -0.581（p < 0.001））。PI 与 TrueBeam STx 和 Trilogy 中的 MLC 误差呈第二强相关性（分别与 r = 0.861（p < 0.001）和 r = 0.767（p < 0.001））。总体而言，PI 与每个计划交付精度测量值呈中度强相关性。
结论
PI 与每个计划交付精度测量值呈中度强相关性，因此是预测 IMRT 交付精度的有用指标。
Zotero 插件