Gel dosimetry for brachytherapy dose delivery validation

用于近距离放射治疗剂量输送验证的凝胶剂量测定

• 批准号: 508528-2017
• 负责人: Schreiner, John
• 金额: $ 6.99万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Collaborative Health Research Projects
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=664524
• 关键词: Gel; dosimetry; brachytherapy; dose; delivery

Modern radiation therapy has advanced through the development of techniques to better**shape radiation dose to tumour volumes while minimizing adverse dose effects to surrounding**normal tissue. In brachytherapy (Greek: near therapy) radiation sources are placed into the**tumour under robotic control. Placing a dose detector near the radiation source affects dose**in adjacent regions. For this reason, dose delivery validation in brachytherapy is usually**based on quality assurance of very simple geometries that are not as complex as those**clinically encountered during patient treatments.**A promising technique for dose measurement is gel dosimetry which is based on imaging**special gel systems which change when irradiated. The changes can be imaged with various**techniques available to our laboratory and provide the spatial distribution of the dose. The**gels mimic tissue and so the dose measured corresponds to the dose to a patient. As a result,**dose measurement is more accurate and we can validate a planned delivery for a given**patient before treatment starts.**We propose to: i) test current gel formulations for their effectiveness and shortcomings in**brachytherapy dosimetry and create, characterize and test new formulations designed**specifically for brachytherapy applications; ii) develop standard protocols and phantoms**specific to brachytherapy dose delivery; and, iii) develop software to evaluate and compare**gel-measured doses to measurements using conventional tools and to planned dose delivery.**Testing of planned delivery is performed daily in other radiation therapy delivery with x-ray**machines but is not yet available for brachytherapy. We will be the first to develop patient**specific dose delivery validation for brachytherapy.

现代放射治疗通过技术的发展而进步，以更好地将辐射剂量调整到肿瘤体积，同时最大限度地减少对周围正常组织的不良剂量影响。在近距离放射治疗（希腊语：近距离治疗）中，放射源在机器人控制下被放置到肿瘤中。在辐射源附近放置剂量探测器会影响相邻区域的剂量 **。因此，近距离放射治疗中的剂量输送验证通常 ** 基于非常简单的几何形状的质量保证，这些几何形状不像患者治疗过程中临床遇到的几何形状那么复杂。一种有前途的剂量测量技术是凝胶剂量测定法，它是基于成像 ** 特殊的凝胶系统，当照射时会发生变化。这些变化可以用我们实验室可用的各种 ** 技术成像，并提供剂量的空间分布。** 凝胶模拟组织，因此测量的剂量对应于患者的剂量。因此，** 剂量测量更准确，我们可以在治疗开始前验证给定 ** 患者的计划输送。**我们建议：i）测试当前凝胶制剂在 ** 近距离放射治疗剂量测定中的有效性和缺点，并创建、表征和测试专门为近距离放射治疗应用设计的新制剂 **; ii）开发专门用于近距离放射治疗剂量输送的标准方案和体模 **; iii）开发软件，以评估和比较 ** 凝胶测量剂量与使用常规工具测量的剂量以及计划的剂量输送。在其他放射治疗输送中，使用X射线 ** 机器每天进行计划输送测试，但尚不适用于近距离放射治疗。我们将是第一个为近距离放射治疗开发患者特定剂量输送验证的公司。