A Proton Tomography System for Optimization of Proton Therapy

用于优化质子治疗的质子断层扫描系统

• 批准号: 10010030
• 负责人: Don F DeJongh
• 金额: $ 107.65万
• 依托单位: PROTONVDA LLC
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-04-01 至 2022-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10010030
• 关键词: Algorithmic Software; Anatomy; Clinical; Computer software; Computers; Data; Development; Diagnostic radiologic examination; Distal; Dose; Ensure; Environment; Film; Grant; Head; Image; Imaging Phantoms; Individual; Malignant Neoplasms; Measurement; Measures; Mechanics; Methods; Movement; Normal tissue morphology; Optics; Organ; Patient-Focused Outcomes; Patients; Phase; Positioning Attribute; Proton Radiation; Protons; Radiation Dose Unit; Radiation Oncology; Radiation therapy; Research Personnel; Risk; Rotation; Scanning; Site; Small Business Innovation Research Grant; System; Technology; Testing; Tissues; Toxic effect; Uncertainty; United States; Universities; X-Ray Computed Tomography; base; clinically relevant; data acquisition; data streams; detector; experience; image reconstruction; imaging system; improved; indexing; pre-clinical; proton beam; proton therapy; prototype; reconstruction; tomography; treatment planning; tumor

Abstract Proton therapy is rapidly expanding in the United States. Currently, the calculation of proton range in proton therapy patients is based on a conversion of CT Hounsfield Units of patient tissues to proton relative stopping power. Uncertainties in this conversion necessitate larger proximal and distal planned target volume margins. These larger margins increase the dose to nearby healthy tissues, causing unwanted and avoidable toxicities. Proton computed tomography (pCT) avoids these uncertainties by directly measuring proton stopping power, and this can drastically reduce the planned target volume, thus directly reducing toxicity. Proton radiography (pRad) has the capability to accurately align the patient to the proton beam and quantify anatomical consistency and proton range in the treatment position just prior to treatment, which will lead to more consistent target coverage, yielding improved patient outcomes. Clinical proton imaging systems must provide pCT as well as pRad capability. This project aims to achieve the advances that will ensure the full functionality of proton imaging in a clinical environment and demonstrate a proton imaging system with a path to FDA clearance. These key improvements in proton therapy are an essential requirement as the field of radiation oncology moves toward hypofractionation (higher dose treatments given in fewer fractions). ProtonVDA (https://www.protonvda.com/), with a recent Phase II SBIR grant, has demonstrated the first fully functional prototype of a system able to take and promptly display accurate pRad images with clinical proton pencil beam scanning systems using very low intensity to analyze individual protons. While a fully functional pCT system does not yet exist, this project will involve co-investigators from Loma Linda University with extensive experience with a preclinical pCT system. ProtonVDA’s technology will be used to develop a fully functional pCT prototype. Whereas pRad uses a single beam direction, pCT requires a complete set of angles spanning at least 180 degrees in the object reference frame. This can be achieved either with a fixed pCT system and proton beam while rotating the object or with a fixed object while rotating the pCT system along with the proton beam. In both cases, precise information on any mechanical movements within the beam delivery, imaging, and object reference frames is essential, because effects from axis misalignment or mechanical sagging can significantly degrade image quality. Therefore, the prototype will incorporate an optical tracking system to measure and correct for these movements. Project collaborators from Provision (https://provisionhealthcare.com/) have previously demonstrated the use of optical tracking for patient positioning. After development of the pCT system, tests using pCT-planned proton beams applied to phantoms containing dosimetric films will verify the clinically relevant accuracy of pCT.

抽象的 质子治疗在美国正在迅速扩张。目前，质子中质子射程的计算 治疗患者基于将患者组织的 CT 亨斯菲尔德单位转换为质子相对停止 力量。这种转换的不确定性需要更大的近端和远端计划目标体积裕度。 这些较大的边缘增加了附近健康组织的剂量，导致不必要的和可避免的毒性。 质子计算机断层扫描 (pCT) 通过直接测量质子阻止本领来避免这些不确定性， 这可以大大减少计划的目标体积，从而直接降低毒性。质子射线照相术 (pRad) 能够准确地将患者与质子束对齐并量化解剖学 治疗前治疗位置的一致性和质子范围，这将导致更多 一致的目标覆盖范围，改善患者的治疗效果。临床质子成像系统必须提供 pCT 以及 pRad 功能。该项目旨在实现确保完整功能的进步 质子成像在临床环境中的应用，并展示质子成像系统可通过 FDA 审批 清除。质子治疗的这些关键改进是放射领域的基本要求 肿瘤学朝着大分割方向发展（以更少的分割给予更高剂量的治疗）。 ProtonVDA (https://www.protonvda.com/) 最近获得了第二阶段 SBIR 资助，展示了第一个完全 能够使用临床质子拍摄并迅速显示准确的 pRad 图像的系统功能原型 笔形束扫描系统使用非常低的强度来分析单个质子。虽然功能齐全 pCT 系统尚不存在，该项目将涉及罗马琳达大学的联合研究人员 在临床前 PCT 系统方面拥有丰富的经验。 ProtonVDA 的技术将用于开发完全 功能性 PCT 原型。 pRad 使用单个光束方向，而 pCT 需要一组完整的角度 在对象参考系中跨越至少 180 度。这可以通过固定 pCT 来实现 系统和质子束，同时旋转物体或固定物体，同时旋转 PCT 系统 与质子束。在这两种情况下，都可以获得有关梁内任何机械运动的精确信息 传输、成像和物体参考系至关重要，因为轴未对准或 机械下垂会显着降低图像质量。因此，原型将采用光学 跟踪系统来测量和纠正这些运动。 Provision 的项目合作者 (https://provisionhealthcare.com/) 之前已经演示了光学跟踪对患者的使用 定位。开发出 pCT 系统后，使用 pCT 计划的质子束应用于模型进行测试 包含剂量测定胶片将验证 PCT 的临床相关准确性。