4D treatment plan optimization and motion detection via radiography

通过射线照相进行 4D 治疗计划优化和运动检测

• 批准号: 85275969
• 负责人: Professor Dr. Christoph Bert
• 金额: --
• 依托单位: Strahlenklinik
• 依托单位国家: 德国
• 项目类别: Clinical Research Units
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/85275969?language=en
• 关键词: 4D; treatment; plan; optimization; motion

Ion beam radiotherapy, narrow scanning beams are used to deliver highly localized dose distributions to the patient. In treatments of organs moving during the beam delivery interplay effects between the two motions occur, resulting in undesired dose distributions. To minimize those effects, several motion mitigation techniques were proposed. This project concentrates on gating (beam delivered only in a particular motion phase) and tracking (target motion followed by the beam).To enable their clinical implementation, dedicated 4D treatment planning as well as a high precision detection of the actual target position is necessary.Within the first PhD-project we plan to implement 4D optimization of treatment plans for scanned ion beam therapy. These offer the advantage that the additional degrees of freedom given by the moving target are exploited in the optimization process. We will focus on 4D optimization for beam tracking with the aim to achieve tracking without energy variation and beam gating.For determination of the internal target position, we will investigate ion radiography in second PhD-work. Radiography provides the potential of high contrast images gained at low dose. The pixelized semiconductor detector “Timepix” will be used to register single ions behind the patient. Based on the measurement of their energy deposition in the detector, direction and fluence, imaging techniques will be developed. The technique with the best performance to visualize moving targets at a minimal dose to the patient will be identified.If successful, the techniques of dedicated 4D treatment plan optimization and target position detection will allow improved radio-therapeutic treatments of tumors in moving organs like lung, liver and pancreas by scanning ion beams. The techniques will be clinically implemented at the HIT facility in Heidelberg in the near future, what enables to exploit this high-end radiotherapy for radioresistant tumors in those new locations.

离子束放射治疗，窄扫描束用于向患者提供高度局部的剂量分布。在治疗光束传输过程中移动的器官时，两种运动之间会发生相互作用，导致不期望的剂量分布。为了最大限度地减少这些影响，提出了几种运动缓解技术。该项目专注于选通（仅在特定运动阶段传递光束）和跟踪（光束跟随目标运动）。为了实现其临床实施，需要专门的 4D 治疗计划以及对实际目标位置的高精度检测。在第一个博士项目中，我们计划对扫描离子束治疗的治疗计划实施 4D 优化。这些提供的优点是在优化过程中利用了移动目标给出的附加自由度。我们将重点关注射束跟踪的 4D 优化，旨在实现无能量变化和射束选通的跟踪。为了确定内部目标位置，我们将在第二个博士工作中研究离子射线照相术。射线照相术提供了以低剂量获得高对比度图像的潜力。像素化半导体探测器“Timepix”将用于记录患者身后的单个离子。基于对探测器中能量沉积、方向和注量的测量，将开发成像技术。将确定以最小剂量对患者显示移动目标的最佳性能技术。如果成功，专用 4D 治疗计划优化和目标位置检测技术将能够通过扫描离子束改进肺、肝和胰腺等移动器官中肿瘤的放射治疗。这些技术将在不久的将来在海德堡的 HIT 设施进行临床实施，从而能够在这些新地点利用这种高端放射疗法治疗放射抗性肿瘤。