Accelerated x-ray therapy planning system PEREGRINE

加速 X 射线治疗计划系统 PEREGRINE

• 批准号: 6787955
• 负责人: PAUL S NIZIN
• 金额: $ 10万
• 依托单位: NOMOS CORPORATION
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-04-08 至 2006-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6787955
• 关键词: artificial intelligence; bioengineering /biomedical engineering; computed axial tomography; computer assisted medical decision making; computer assisted patient care; computer program /software; computer simulation; computer system design /evaluation; electromagnetic radiation; mathematics; patient care planning; radiation dosage; radiation therapy; technology /technique development

DESCRIPTION (provided by applicant): Computerized radiation therapy planning systems (RTP) are essential in Radiation Oncology for quantitative evaluation of radiation doses prior to patient treatment. Among currently available computational methods, the Monte Carlo method of calculating dose distributionsis most universal and accurate. It is believed that Monte Carlo software packages will become a central part of future RTP systems. The limiting problem with current Monte Carlo codes is the length of time (CPU time) required for calculations even when using state-of-the-art hardware. An increase in efficiency of Monte Carlo codes has been demonstrated using algorithms known as variance-reduction techniques (VR techniques), but the calculation times are still too long for routine clinical use. While there is no single VR technique that would make Monte Carlo code clinically viable, a combination of such techniques usually results in improved performance. At present, the only commercial RTP system using Monte Carlo code for photon dose calculations is PEREGRINE from Lawrence Livermore National Laboratory and NOMOS Corporation. PEREGRINE uses several VR techniques. However, it is estimated that a further reduction in CPU time by a factor of 10 would be required to have a clinically efficient system. Our theoretical study and subsequent Monte Carlo results support a new variance-reduction technique (NVR) for photon-beam dose calculations. It is shown that NVR yields up to a 5-fold reduction in CPU time. The long-term objective of the project is to reduce PEREGRIN's CPU time from currently several hours to several; minutes. This will require a combination of NVR with other VR techniques. Within this scope, the specific aims of Phase I are: 1. Development, implementation and validation of a PEREGRINE-specific NVR algorithm. 2. Benchmarking of NVR over the range of clinically useful energies in homogeneous and heterogeneous phantoms. 3. Validation of NVR in the case of patient-specific Monte Carlo calculations using CT based patient anatomy.

描述（由申请人提供）：计算机化放射治疗计划系统（RTP）在放射肿瘤学中对于在患者治疗之前定量评估放射剂量至关重要。目前可用的计算方法中，计算剂量分布的蒙特卡罗方法最为通用和准确。人们相信蒙特卡罗软件包将成为未来RTP系统的核心部分。当前蒙特卡罗代码的限制问题是计算所需的时间（CPU 时间），即使使用最先进的硬件也是如此。使用称为方差减少技术（VR 技术）的算法已经证明了蒙特卡罗代码效率的提高，但计算时间对于常规临床使用来说仍然太长。虽然没有单一的 VR 技术可以使蒙特卡罗代码在临床上可行，但这些技术的组合通常会提高性能。目前，唯一使用蒙特卡罗代码进行光子剂量计算的商业RTP系统是来自劳伦斯利弗莫尔国家实验室和NOMOS公司的PEREGRINE。 PEREGRINE 使用多种 VR 技术。然而，据估计，要拥有一个临床高效的系统，需要将 CPU 时间进一步减少 10 倍。 我们的理论研究和随后的蒙特卡罗结果支持用于光子束剂量计算的新方差减少技术（NVR）。结果表明，NVR 可使 CPU 时间减少多达 5 倍。该项目的长期目标是将PEREGRIN的CPU时间从目前的几个小时减少到几个小时；分钟。这需要将 NVR 与其他 VR 技术相结合。在此范围内，第一阶段的具体目标是： 1. PEREGRINE 专用 NVR 算法的开发、实施和验证。 2. 在同质和异质体模的临床有用能量范围内对 NVR 进行基准测试。 3. 使用基于 CT 的患者解剖结构进行患者特定蒙特卡罗计算时的 NVR 验证。