Accurate, High Resolution 3D Dosimetry.

准确、高分辨率的 3D 剂量测量。

• 批准号: 7035775
• 负责人: MARK OLDHAM
• 金额: $ 25万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-01 至 2008-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7035775
• 关键词: bioimaging /biomedical imaging; computed axial tomography; gel; image enhancement; image processing; measurement; polymers; radiation dosage; radiation therapy; radiation therapy dosage; technology /technique development; three dimensional imaging /topography

DESCRIPTION (provided by applicant): Dose distributions associated with advanced radiation treatments (e.g. intensity modulated radiation therapy, IMRT) typically exhibit complicated steep dose gradients that conform to irregular anatomical surfaces in three-dimensions (3D). Comprehensive verification is difficult to achieve with conventional dosimeters presenting an immediate and substantial problem. In short, rapid advances in the technology to deliver radiation treatments have not been paralleled by corresponding advances in the ability to verify these treatments. A potential solution has emerged in the form of 3D gel-dosimetry utilizing optical-computed-tomography (optical-CT). It is the long-term objective of this proposal to investigate, optimize and develop gel-dosimetry to a level where accuracy is comparable to that of other standard relative clinical dosimeters (e.g. ion-chambers at 3%) while maintaining the unique feature of high spatial resolution in 3D (Imm3 or better). Should this be possible, it would represent a key goal for radiation dosimetry, and could significantly improve and influence clinical practice. The proposal includes the development and use of a model to study the fundamentals of light transport through the gel and scanning system and the transfer of signal and noise to dose reconstruction. The model will also enable optimization of the system and provide a platform of knowledge to guide in the refinement of future gel dosimeters. Gel-dosimeters (polymer and radiochromic gels) will be characterized according to the physical factors affecting accuracy. Finally, an optical-CT gel-dosimetry system is constructed that is capable of high-resolution 3D dose measurement with accuracy consistent with other standard dosimeters. The utility, accuracy and feasibility of the finalized system will be demonstrated by application to dosimetric verification of advanced IMRT, radiosurgery and brachytherapy treatments in the clinic. Completion will result in a 3D dosimetry system capable of unprecedented comprehensive dosimetric verification, and applicability to the spectrum of modern radiation treatments, including IMRT, brachytherapy, radiosurgery and orthovoltage teletherapy.

描述(申请人提供)：与先进的放射治疗(例如，调强放射治疗，IMRT)相关的剂量分布通常表现出复杂的陡峭的剂量梯度，符合三维(3D)的不规则解剖表面。由于传统的剂量计是一个直接和实质性的问题，很难实现全面的验证。简而言之，提供放射治疗的技术的快速进步并不能与验证这些治疗的能力的相应进步相提并论。一个潜在的解决方案已经出现在利用光学计算机断层扫描(光学CT)的3D凝胶剂量测量的形式。这项建议的长期目标是调查、优化和发展凝胶剂量学，使其准确度可与其他标准相对临床剂量计(例如，3%的电离室)相媲美，同时保持3D(Imm 3或更高)高空间分辨率的独特功能。如果这是可能的，这将是辐射剂量学的一个关键目标，并可能显著改善和影响临床实践。 该提案包括开发和使用一个模型来研究通过凝胶和扫描系统的光传输的基本原理，以及信号和噪声向剂量重建的转移。该模型还将实现系统的优化，并提供一个知识平台来指导未来凝胶剂量计的改进。凝胶剂量计(聚合物和辐射变色凝胶)将根据影响准确度的物理因素进行表征。最后，构建了一个光学-CT凝胶剂量测量系统，该系统能够进行高分辨率的三维剂量测量，其测量精度与其他标准剂量计一致。最终系统的实用性、准确性和可行性将通过临床应用于先进的调强放疗、放射外科和近距离放射治疗的剂量学验证而得到验证。 完成后将产生一个3D剂量测量系统，能够进行前所未有的全面剂量学验证，并适用于现代放射治疗的频谱，包括调强放射治疗、近距离放射治疗、放射外科和正压远程治疗。