Project 4: Development and validation of Pencil Beam Scanning methodology for particle FLASH radiotherapy

项目摘要 本计画将利用笔形射束扫描技术，探讨闪光辐射的时空传递。 现代激光束扫描（PBS）技术可以提供空间非均匀（类高斯）笔形光束 在非常高的瞬时剂量率，以浅和深层次的肿瘤;然而，低剂量尾部的一个 笔形射束和用于大目标的相对较慢的体积扫描速度产生可变剂量率， 选择目标或正常组织位置。这种时空变化的影响仍然未知， 闪即使在相同的（平均）剂量率下，也存在可以提供FLASH治疗的简并性 通过不同的时间-剂量序列。有必要在以下背景下研究剂量输送的时间结构： FLASH治疗，以及测量和记录每个FLASH治疗，以便可以 更好地理解。我们的中心假设是，质子PBS可以优化，以提供FLASH增强 放射治疗与现有的加速器技术。该提案的目的是： 目的1 -研究时空变化和SOBP与通过PBS光束拍摄的关系。 目标2 -基于PBS的FLASH的时空生物有效剂量模型的开发 质子治疗 目标3 -开发快速剂量记录仪器、图像引导定位系统、质量 保证程序和端到端验证。 该项目的成功将证明使用质子将FLASH输送到大治疗体积的能力 PBS第一次。结合质子治疗准确向深部靶点输送剂量的能力， 这将允许将PBS FLASH质子治疗转化为早期临床试验研究。

Project Summary This project will investigate spatio-temporal delivery of FLASH radiation using pencil beam scanning technology. Modern Pencil Beam Scanning (PBS) technology can deliver spatially non-uniform (Gaussian-like) pencil beam in very high instantaneous dose rate to both shallow and deep-seated tumors; however, the low dose tail of a pencil beam and the relatively slow volume scanning speed for large targets generate a variable dose rate at selected target or normal tissue locations. The impact of this spatial-temporal variation is still unknown for FLASH. Even at the same (averaged) dose rate, degeneracy exists that the FLASH treatment can be delivered by different time-dose sequences. There is a need to study the timing structure of dose delivery in the context of FLASH treatment, as well as measuring and documenting each FLASH treatment so that the outcome can be better understood. Our central hypothesis is that proton PBS can be optimized to deliver FLASH enhanced radiotherapy with existing accelerator technology. The aims of the proposal are: Aim 1 - Investigation of spatio-temporal variations and SOBP versus shoot through PBS beams. Aim 2 - Development of a spatial-temporal biological effective dose model for PBS-based FLASH proton therapy. Aim 3 - Development of fast dose recording instrumentation, image guided positional systems, quality assurance procedures, and end-to-end validation. Success of this project will demonstrate the ability to deliver FLASH to large treatment volumes using proton PBS for the first time. Combined with the ability of proton therapy to accurately deliver dose to deep targets, this will allow translation of PBS FLASH proton therapy to early stage clinical trial studies.