With the rapid increase in clinical treatments with MRI-linacs, a consistent, harmonized and sustainable ground for reference dosimetry in MRI-linacs is needed. Specific for reference dosimetry in MRI-linacs is the presence of a strong magnetic field. Therefore, existing Code of Practices (CoPs) are inadequate. In recent years, a vast amount of papers have been published in relation to this topic. The purpose of this review paper is twofold: to give an overview and evaluate the existing literature for reference dosimetry in MRI-linacs and to discuss whether the literature and datasets are adequate and complete to serve as a basis for the development of a new or to extend existing CoPs.

This review is prefaced with an overview of existing MRI-linac facilities. Then an introduction on the physics of radiation transport in magnetic fields is given. The main part of the review is devoted to the evaluation of the literature with respect to the following subjects:

• beam characteristics of MRI-linac facilities;

• formalisms for reference dosimetry in MRI-linacs;

• characteristics of ionization chambers in the presence of magnetic fields;

• ionization chamber beam quality correction factors; and

• ionization chamber magnetic field correction factors.

The review is completed with a discussion as to whether the existing literature is adequate to serve as basis for a CoP. In addition, it highlights subjects for future research on this topic.

随着MRI-直线加速器临床治疗的迅速增加，需要为MRI-直线加速器的参考剂量法提供一致，协调和可持续的基础。MRI直线加速器的参考剂量测定法特有的是存在强磁场。因此，现有的行为准则（CoP）不足。近年来，与该主题相关的大量论文已经发表。本文的目的是双重的：概述和评估MRI直线加速器参考剂量学的现有文献，并讨论文献和数据集是否足够和完整，以作为新文献或文献的基础。扩展现有的CoP。

这篇综述的开头是对现有MRI-直线加速器设施的概述。然后介绍了磁场中辐射传输的物理学。审查的主要内容是针对以下主题的文献评估：

•MRI直线加速器设施的光束特性；

•MRI直线加速器参考剂量测定的形式主义；

•存在磁场时电离室的特性；

•电离室光束质量校正因子；和

•电离室磁场校正因子。

通过讨论有关现有文献是否足够作为CoP的基础来完成审查。此外，它突出显示了有关此主题的未来研究主题。