Novel methods and instruments for accurate tracking of ionizing radiation delivery for medical physics applications

这项工作的目标是创造新的工具和方法，以确保能够安全和准确地提供复杂的放射治疗，从而提高成功的机会。目前正在追求三个具体目标。(1)研制一种可在线测量三维辐射剂量的辐射剂量探测器。这将是第一个能够以毫米级精度实时测量完整放射治疗的探测器。它用于放射治疗质量控制将是对目前仅在有限数量的平面上测量剂量的方法的改进，这使得很大一部分剂量分布没有得到验证。(2)研制一种用于体内精确测量的微型组织当量探测器阵列。这种不显眼的探测器阵列将在患者接受治疗时提供精确的辐射剂量测量。此外，我们新的信号处理方法将允许在测量期间检查探测器响应的完整性。完整性检查对于活体测量很重要，因为机械应力或其他危险可能导致错误的剂量读数。(3)自动跟踪放射治疗过程中发生的解剖变化。将开发一种软件来分析在放射治疗过程中定期获取的图像，以检测解剖变化的幅度和位置。然后，我们将把这些变化与计划的剂量分布和处于危险中的敏感器官的位置联系起来，以检测与预期计划的偏差并相应地进行调整。

The goal of this work is to create new instruments and methods for guaranteeing that complex radiation treatments can be delivered safely and accurately thus improving chances of success. Three specific aims are being pursued. (1) To develop a radiation dose detector capable of online measurement of radiation doses in three dimensions. This would be the first detector capable of measuring a complete radiation treatment in real-time with millimeter-size precision. Its use for radiotherapy quality control would be an improvement over the current approach of measuring the dose only in a limited number of planes, which leaves a large part of the dose distribution unverified. (2) To develop a miniature tissue-equivalent detector array for accurate in vivo measurement. This unobtrusive detector array will provide precise radiation dose measurements while patients are being treated. Furthermore, our novel approach for signal processing will allow checking the integrity of the detector response during measurements. Integrity checks are important for in vivo measurements because mechanical stress or other hazards could cause erroneous dose readings. (3) To automatically track anatomical changes happening during the course of radiation treatments. A software will be developed to analyze images acquired regularly during the course of radiation treatments to detect the amplitude and location of anatomical changes. We will then put these changes in relation with the planned dose distribution and the location of sensitive organs at risk to detect deviation from the intended plan and adapt it accordingly.