Quality assurance for the geometric accuracy of cone-beam CT guidance in radiation therapy
Quality assurance for the geometric accuracy of cone-beam CT guidance in radiation therapy
复制标题
DOI：
10.1016/j.ijrobp.2007.06.086
复制
发表时间：
2008-01-01
影响因子：
7
通讯作者：
Jaffray, David A.
中科院分区：
文献类型：
--
作者：
Bissonnette, Jean-Pierre;Moseley, Doug;Jaffray, David A.
体积X射线图像引导放射治疗系统的引入允许改进对患者设置和内部器官运动中的几何变化的管理。随着这些系统成为常规的临床模式，我们提出了一个日常的质量保证（QA）计划，锥束计算机断层扫描（CBCT）与直线加速器集成。在这项工作中使用的图像引导系统相结合的直线加速器与传统的X射线管和非晶硅平板探测器安装从加速器中心束轴正交。本文重点介绍与CBCT系统几何精度密切相关的日常QA协议，并根据我们诊所使用的7种CBCT系统3年多的经验提出公差水平。每月的几何校准测试证明了弯曲运动的长期稳定性，其可重现性在+/- 0.5 mm（95%置信区间）内。日常QA程序表明，对于刚性体模，图像引导过程的准确度平均可在1 mm内，99%置信区间为+/- 2 mm。（C）2008 Elsevier Inc.
The introduction of volumetric X-ray image-guided radiotherapy systems allows improved management of geometric variations in patient setup and internal organ motion. As these systems become a routine clinical modality, we propose a daily quality assurance (QA) program for cone-beam computed tomography (CBCT) integrated with a linear accelerator. The image-guided system used in this work combines a linear accelerator with conventional X-ray tube and an amorphous silicon flat-panel detector mounted orthogonally from the accelerator central beam axis. This article focuses on daily QA protocols germane to geometric accuracy of the CBCT systems and proposes tolerance levels on the basis of more than 3 years of experience with seven CBCT systems used in our clinic. Monthly geometric calibration tests demonstrate the long-term stability of the flex movements, which are reproducible within +/- 0.5 mm (95% confidence interval). The daily QA procedure demonstrates that, for rigid phantoms, the accuracy of the image-guided process can be within 1 mm on average, with a 99% confidence interval of +/- 2 mm. (C) 2008 Elsevier Inc.