文章：

质子远距治疗多场景稳健性评估方法与测量结果的比较

Comparison of a Multi-Scenario Robustness Evaluation Method with Measurements for Proton Teletherapy

原文发布日期：6 September 2025

DOI: 10.3390/cancers17172927

类型: Article

开放获取: 是

英文摘要：

Background/Objectives: Multi-scenario calculational methods have been used to evaluate proton teletherapy plan robustness but few studies have been performed to determine the accuracy of these calculational methods. This study evaluates a multi-scenario method by comparing calculations to measurements made in phantoms that simulate the effects of possible uncertainties.Methods: Plans were made using four phantoms in which the delivered dose was highly sensitive to positional and penetration uncertainties. The effects of alignment and penetration uncertainties on the dose distributions of each of those phantoms were simulated by performing calculations using nine different uncertainty scenarios and comparing the calculations to measurements with induced physical alignment displacements. Measured dose distributions were obtained by exposing films placed inside the phantoms and extracting multiple linear profiles. The maximum and minimum doses obtained for each of the calculational scenarios were compared with the measured dose profiles. In addition, comparisons of DVHs for nominal and uncertainty scenarios were performed.Results: The results showed that, under the influence of uncertainties, the minimum dose for the four phantoms decreased by more than 20 Gy, the V95%coverage fluctuated by more than 10%, but the maximum dose parameter changed by less than 5 Gy. This was expected, as no margins for uncertainties were applied around the targets. The envelope bounded by the maximum and minimum possible calculated doses contained most of the measurements, although the shapes of the dose profiles displayed some mismatches for wedge and head phantoms. There were a few points where the measured maximum dose for bone and lung slab phantom cases was slightly higher than the maximum dose calculated from the nine scenarios.Conclusions: This study demonstrates that a nine-scenario method can adequately evaluate the robustness of simple mono-directional plans containing heterogeneities.

摘要翻译： 

背景/目的：多场景计算方法已被用于评估质子远距治疗计划的稳健性，但关于这些计算方法准确性的研究较少。本研究通过将计算与模拟潜在不确定性的体模测量结果进行比较，评估了一种多场景方法的准确性。方法：使用四个体模制定计划，这些体模中传递的剂量对位置和穿透不确定性高度敏感。通过采用九种不同的不确定性场景进行计算，并将计算结果与诱导物理位移的测量结果进行比较，模拟了对齐和穿透不确定性对各体模剂量分布的影响。测量剂量分布通过将胶片置于体模内曝光并提取多条线性剖面获得。将各计算场景获得的最大和最小剂量与测量的剂量剖面进行比较。此外，还对标称场景和不确定性场景的剂量体积直方图进行了比较。结果：结果显示，在不确定性的影响下，四个体模的最小剂量下降超过20 Gy，V95%覆盖率波动超过10%，但最大剂量参数变化小于5 Gy。这一结果符合预期，因为未在靶区周围设置不确定性边界。尽管楔形和头部体模的剂量剖面形状存在一些不匹配，但由计算的最大和最小可能剂量界定的包络包含了大部分测量结果。在骨和肺板体模案例中，少数测量点的最大剂量略高于九种场景计算的最大剂量。结论：本研究证明，九场景方法能够充分评估包含异质性的简单单向计划的稳健性。

原文链接：

Comparison of a Multi-Scenario Robustness Evaluation Method with Measurements for Proton Teletherapy