Over the last few years, magnetic resonance image-guided radiotherapy systems have been introduced into the clinic, allowing for daily online plan adaption. While quality assurance (QA) is similar to conventional radiotherapy systems, there is a need to introduce or modify measurement techniques. As yet, there is no consensus guidance on the QA equipment and test requirements for such systems. Therefore, this report provides an overview of QA equipment and techniques for mechanical, dosimetric, and imaging performance of such systems and recommendation of the QA procedures, particularly for a 1.5T MR-linac device. An overview of the system design and considerations for QA measurements, particularly the effect of the machine geometry and magnetic field on the radiation beam measurements is given. The effect of the magnetic field on measurement equipment and methods is reviewed to provide a foundation for interpreting measurement results and devising appropriate methods. And lastly, a consensus overview of recommended QA, appropriate methods, and tolerances is provided based on conventional QA protocols. The aim of this consensus work was to provide a foundation for QA protocols, comparative studies of system performance, and for future development of QA protocols and measurement methods.

中文翻译：

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Elekta Unity系统的机器QA：Elekta MR-直线加速器联盟的报告

在过去的几年中，磁共振图像引导的放射治疗系统已被引入诊所，可以进行日常在线计划调整。尽管质量保证（QA）与常规放射治疗系统相似，但仍需要引入或修改测量技术。迄今为止，关于此类系统的质量检查设备和测试要求尚无共识性指南。因此，本报告概述了此类系统的机械，剂量和成像性能的QA设备和技术，并提出了QA程序的建议，尤其是针对1.5T MR直线加速器的设备。给出了系统设计的概述以及QA测量的注意事项，特别是机器几何形状和磁场对辐射束测量的影响。回顾了磁场对测量设备和方法的影响，为解释测量结果和设计适当的方法提供了基础。最后，根据传统的质量检查协议，对推荐的质量检查，适当的方法和公差提供了共识性概述。这项共识性工作的目的是为质量保证协议，系统性能的比较研究以及质量保证协议和测量方法的未来发展提供基础。