Accurate, High Resolution 3D Dosimetry.

准确、高分辨率的 3D 剂量测量。

• 批准号: 6884580
• 负责人: MARK OLDHAM
• 金额: $ 24.95万
• 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 2007-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6884580
• 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（由申请人提供）：与高级放射治疗（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剂量梯度，符合三维（3D）不规则解剖表面。常规剂量计难以实现全面的验证，这是一个直接和实质性的问题。简而言之，放射治疗技术的快速发展并没有与验证这些治疗的能力的相应进步同步。一种潜在的解决方案是利用光学计算机断层扫描（光学ct）进行三维凝胶剂量测定。本提案的长期目标是研究、优化和发展凝胶剂量法，使其精度与其他标准相对临床剂量计（例如，离子室为3%）相当，同时保持3D （Imm3或更高）的高空间分辨率的独特特征。如果这是可能的，它将代表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。