ONLINE SETUP OF CONFORMAL RADIOTHERAPY USING AMFPIS

使用 AMFPIS 在线设置适形放射治疗

• 批准号: 6475849
• 负责人: KWOK L LAM
• 金额: $ 22.08万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-12-27 至 2003-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6475849
• 关键词: abdomen neoplasm; autoradiography; bioengineering /biomedical engineering; bioimaging /biomedical imaging; biomedical equipment development; brain imaging /visualization /scanning; breast neoplasms; clinical biomedical equipment; clinical research; computer assisted patient care; computer program /software; digital imaging; head /neck neoplasm; health services research tag; human subject; image enhancement; lung neoplasms; neoplasm /cancer radiation therapy; online computer; radiation therapy dosage; respiratory imaging /visualization

A basic assumption for full realization of conformal radiotherapy (CRT) is that accurate daily patient treatment setup localization and online treatment monitoring leads to improved targeting of tissues tagged for treatment. Validation of this concept would facilitate significant reductions in treated volumes, allowing investigations of improved local control with higher delivered doses at safe levels of normal tissue toxicity. Electronic portal imaging devices (EPIDs) were in large part developed to fulfill this promise. However, in practice current EPIDs suffer from poor image quality relative to radiographic film, high dose (for fields often hot used for treatment themselves), and lack of integration with automated treatment planning and delivery systems. Thus, daily patient setup variations are not generally accounted for at the time of treatment, but assessed off-line with respect to target margins settled upon as compromises between the desires of CRT and treatment efficiency. Such applications, while useful, do not realize dramatic reduction in treatment volumes. It is a hypothesis of this study that major factors inherent in the lack of online use of EPIDs lie in the current detector technology. Over the last decade there has been great interest in two- dimensional sensor arrays based on thin-film electronics for use in x-ray imaging. Recently variety of these area devices (generically categorized as active matrix flat panel imagers (AMFPIs) have become available for basic investigation, as have a few clinical EPID prototypes employing AMFPIs. These devices promise to |improve the quality of megavoltage portal images via low contrast detail sensitivity similar to film, doses smaller than conventional EPIDs or film, and digital image presentation in a sufficiently rapid fashion for online verification and monitoring of tumor position for CRT. It is the long term objective of the current study to investigate the basic hypothesis that AMFPIs have t e required characteristics to make online patient setup and online treatment monitoring possible; thus fulfilling the quest for minimal target volume expansion for inclusion of daily treatment variations. The investigation will include testing the hypotheses that: a) the improvement in image quality of AMFPIs will result in superior image feature localization accuracy and speed and at a lower dose than current EPIDs or film systems; b) the improvements serve as sufficient conditions for clinical implementation of online daily setup and online monitoring of treatments, and c) the improvements will reduce variations in treatment fields thus allowing reduced treatment volumes.

完全实现保形放疗的基本假设 （CRT）是准确的日常患者治疗设置定位和在线 治疗监测可改善标记的组织的靶向 治疗。对此概念的验证将有助于大幅减少 在经过处理的卷中，可以通过调查改进的局部控制 在正常组织毒性的安全水平下，较高的剂量剂量。电子的 门户成像设备（Epids）在很大程度上是为实现这一目标的 承诺。但是，实际上当前的EPID遭受图像质量差 相对于射线照相膜，高剂量（对于通常用于田间的田地 本身治疗），并且缺乏与自动处理的整合 计划和交付系统。因此，每天的患者设置变化不是 通常在治疗时考虑，但与 尊重目标边缘，因为欲望之间的妥协 CRT和治疗效率。这样的应用程序虽然有用，但却没有意识到 治疗量的急剧减少。这是这项研究的假设 缺乏在线使用EPID的主要因素在于 探测器技术。在过去的十年中，人们对两个人产生了极大的兴趣 - 尺寸传感器阵列基于薄膜电子设备用于X射线 成像。这些区域设备的最近多种多样（通常归类为 主动矩阵平板成像仪（AMFPI）已用于基本 研究，使用AMFPI的一些临床流行原型。这些 设备有望通过低 对比细节敏感性类似于胶片，剂量小于常规的剂量 Epids或Film和数字图像以足够快的方式演示 用于在线验证和监测CRT的肿瘤位置。是 当前研究的长期目标研究基本假设 AMFPI具有使在线患者设置和 在线治疗监测可能；从而实现了最小的追求 目标体积扩大，包括每日治疗变化。这 调查将包括测试以下假设：a） AMFPI的图像质量将导致出色的图像特征本地化 与当前的EPID或膜系统相比，准确性和速度以及剂量较低； b） 这些改进是临床实施的足够条件 在线每日设置和在线监视治疗，c）改进 将减少治疗领域的变化，从而减少治疗 卷。