Department of Radiology, University of Minnesota, Minneapolis, Minnesota, USA.
Mallinckrodt Institute of Radiology, Washington University at St. Louis, St Louis, Missouri, USA.
Med Phys. 2024 Oct;51(10):7038-7046. doi: 10.1002/mp.17351. Epub 2024 Aug 21.
Measurement of static magnetic field (B) homogeneity is an essential component of routine MRI system evaluation. This report summarizes the work of AAPM Task Group (TG) 325 on vendor-specific methods of B homogeneity measurement and evaluation. TG 325 was charged with producing a set of detailed, step-by-step instructions to implement B homogeneity measurement methods discussed in the American College of Radiology (ACR) MRI Quality Control Manual using specific makes and models of MRI scanners. The TG produced such instructions for as many approaches as was relevant and practical on six currently available vendor platforms including details of software/tools, settings, phantoms, and other experimental details needed for a reproducible protocol. Because edits to these instructions may need to be made as vendors enter and exit the market and change available tools, interfaces, and access levels over time, the step-by-step instructions are published as a living document on the AAPM website. This summary document provides an introduction to B homogeneity testing in MRI and several of the common methods for its measurement and evaluation. A living document on the AAPM website provides vendor-specific step-by-step instructions for performing these tests to facilitate accurate and reproducible B homogeneity evaluation on a routine basis.
磁场（B）均匀性的测量是磁共振成像（MRI）系统常规评估的重要组成部分。本报告总结了美国医学物理师协会（AAPM）工作组 325 关于特定供应商的 B 均匀性测量和评估方法的工作。TG325 的任务是使用特定制造商和型号的 MRI 扫描仪，为美国放射学院（ACR）MRI 质量控制手册中讨论的 B 均匀性测量方法制定一套详细的、逐步的实施说明。TG 针对目前市场上可用的六个供应商平台上的许多相关和实用的方法制定了这些说明，包括软件/工具、设置、体模和其他重现性协议所需的详细信息。由于供应商的进入和退出市场以及可用工具、接口和访问级别随时间的变化，这些说明可能需要进行编辑，因此逐步说明以在线文档的形式发布在 AAPM 网站上。本摘要文件介绍了 MRI 中的 B 均匀性测试以及几种常用的测量和评估方法。AAPM 网站上的在线文档提供了特定供应商的逐步说明，用于执行这些测试，以方便在常规基础上进行准确和可重现的 B 均匀性评估。
