Purpose: Development of a novel interactive visualization approach for the exploration of radiotherapy treatment plans with a focus on overlap volumes with the aim of healthy tissue sparing. Methods: We propose a visualization approach to include overlap volumes in the radiotherapy treatment plan evaluation process. Quantitative properties can be interactively explored to identify critical regions and used to steer the visualization for a detailed inspection of candidates. We evaluated our approach with a user study covering the individual visualizations and their interactions regarding helpfulness, comprehensibility, intuitiveness, decision-making and speed. Results: A user study with three domain experts was conducted using our software and evaluating five data sets each representing a different type of cancer and location by performing a set of tasks and filling out a questionnaire. The results show that the visualizations and interactions help to identify and evaluate overlap volumes according to their physical and dose properties. Furthermore, the task of finding dose hot spots can also benefit from our approach. Conclusions: The results indicate the potential to enhance the current treatment plan evaluation process in terms of healthy tissue sparing.

翻译：目的：开发一种新型交互式可视化方法，用于探索放射治疗计划中与健康组织保护相关的重叠体积。方法：我们提出一种将重叠体积纳入放射治疗计划评估过程的可视化方法。通过交互式探索定量属性，可识别关键区域，并利用这些属性引导可视化对候选区域进行详细检查。我们通过用户研究评估了该方法，涵盖各可视化及其交互在实用性、可理解性、直观性、决策支持和速度方面的表现。结果：与三位领域专家合作开展了用户研究，使用我们的软件对五个数据集（分别代表不同癌症类型及部位）进行任务测试并填写问卷。结果表明，可视化及其交互有助于根据物理特性与剂量属性识别和评估重叠体积。此外，该方法对寻找剂量热点任务亦有助益。结论：研究结果揭示了该方法在提升当前治疗计划评估中健康组织保护效果的潜力。