Developments in radiotherapy physics for accurate, efficient and robust radiation measurements and dose calculations

我的研究领域是放射治疗物理学，这是一个致力于使用物理概念来治疗癌症和其他具有辐射的疾病的领域。我的研究项目集中在两个紧密相连的领域：辐射测量和患者的辐射剂量计算。我的研究计划的长期愿景是寻求对这两个领域所涉及的物理学的更多了解，然后将其转化为新的和/或改进的物理解决方案，以促进更准确、高效和可靠的辐射测量和剂量计算。带着这一愿景，我目前正在探索的目标描述如下。 治疗机产生的辐射的能谱对于剂量计算和理解辐射探测器很重要。我已经为这些极具挑战性的光谱测量开发了一种准确而实用的设备。我的研究小组将使用该设备来探索长期存在的物理问题，即名义上相同(或匹配)的治疗机之间的光谱差异。根据这些知识，我们将改进剂量机器匹配，并开发对机器变化具有健壮性的剂量计算模型。该小组将为其他具有独特特点的专用处理机探索类似的问题。对于辐射探测器阵列，我们将开发改进的方法，使其表征更加准确和稳健。 大多数放射治疗患者接受三种类型的扫描：一种是诊断疾病，一种是专门用于治疗计划和剂量计算的扫描，一种是治疗前的定位扫描。对于急需治疗的患者来说，这是低效的。我的研究小组正在探索一种雄心勃勃的新范式，使用诊断和/或定位扫描来进行治疗计划和剂量计算，消除对中期扫描的需要。在这一范例中存在许多物理挑战，包括扫描仪校准、扫描中的不良物理效应、患者解剖变化、疾病可见性和剂量计算的准确性。我正在利用我的专业知识，利用最先进的辐射设备、模拟方法、校正算法和图像变形软件，领导开发解决这些挑战的物理解决方案。 肠道等健康器官接受的辐射剂量对副作用和治疗结果很重要。由于肠道的流动性和扫描中的模糊性，准确估计肠道剂量是非常具有挑战性的，到目前为止效果有限。我的团队正在开发一个物理平台，其中包括对肠道日常变化的表征，以及一种使用其边界器官自动识别肠道的新方法。这些是我们实现准确的肠道剂量估计的基石。 上述领域的准确性、效率和稳健性的提高将导致更高质量、更具成本效益的放射治疗。

My research field is radiotherapy physics, a field devoted to the use of physics concepts to treat cancer and other diseases with radiation. My research program focuses on two strongly linked domains: radiation measurements, and radiation dose calculations in patients. The long-term vision of my research program is to seek greater understanding of the physics involved in these two domains, then translate this into novel and/or refined physics solutions that facilitate more accurate, efficient and robust radiation measurements and dose calculations. With that vision, the objectives that I am currently exploring are described below. The energy spectrum of the radiation generated by the treatment machine is important for dose calculations and for understanding radiation detectors. I have developed an accurate and practical device for these very challenging spectral measurements. My research group will use the device to explore long standing physics questions regarding the spectral differences among nominally identical (or matched) treatment machines. From this knowledge, we will improve dosimetric machine matching and develop dose calculation models that are robust against machine variations. The group will explore similar questions for other specialized treatment machines with unique characteristics. For radiation detector arrays, we will develop improved methods to make their characterization more accurate and robust. Most radiotherapy patients receive three types of scans: one to diagnose the disease, a special one for treatment planning and dose calculation, and one for positioning before treatment. This is inefficient for patients with urgent need for treatment. My research group is exploring an ambitious new paradigm to use diagnostic and/or positioning scans for treatment planning and dose calculation, eliminating the need for the middle scan. Numerous physics challenges exist in this paradigm, including scanner calibration, undesirable physics effects in scans, patient anatomy changes, disease visibility, and dose calculation accuracy. I am using my expertise to lead the development of physics solutions to these challenges using state-of-the-art radiation facilities, simulation methods, correction algorithms, and image deformation software. Radiation dose received by healthy organs such as the bowel is important for side effects and treatment outcomes. Accurate estimate of bowel dose is very challenging due to bowel mobility and ambiguity in scans, with limited success to date. My group is developing a physics platform that includes characterization of bowel daily changes, as well as a novel approach to automate bowel identification using its boundary organs. These are our building blocks towards accurate bowel dose estimates. The improved accuracy, efficiency and robustness in the areas above will lead to higher-quality, cost-effective radiotherapy.