医疗成象磁共振设备.第1部分:测定实际成象质量参数

[中文适用范围]： 该国际标准规定了测定许多基本医疗 MR 设备图像质量参数的测量程序。本标准中规定的测量程序适用于： - 验收测试中的质量评估； - 稳定性测试中的质量保证。此外，本标准中规定的测量程序也可用于型式试验，尽管这不是本标准的目标。本标准不涉及： - 验收测试和稳定性测试所需的性能水平； - 如果没有另外说明，大于 4 T 的高场 MR 设备的图像质量评估； - 图像质量受 MR 兼容性问题影响； - 特殊诊断程序，例如血流成像、灌注、扩散、放射治疗和图像引导治疗应用； - 型式试验。该标准的范围也仅限于测量测试设备中的图像质量特征，而不是患者图像中的图像质量特征。本标准中规定的测量程序针对： a) 制造商，可以通过执行本标准中描述的验收和稳定性方法来证明符合性， b) 测试机构，可以使用本标准中描述的方法确认 MR 设备的性能， c) 监管机构，可以参考本标准，以及 d) 想要使用本标准中描述的方法进行验收和稳定性测试的责任组织。该标准中定义的基本图像质量参数和测量方法是： - 信噪比、 - 均匀性、 - 切片厚度和切片轮廓、 - 几何失真、 - 空间分辨率和 - 重影。本标准描述了首选的测量程序。它还在附录 A 中描述了替代方法。优选的测试方法可以用替代方法替代。如有必要，可以使用本标准中未描述的其他方法，前提是这些其他测试方法已记录并对照标准中描述的方法进行验证。其他测试方法的验证需要分析测试对相同感兴趣参数的敏感性，并分析测试对其他不相关参数的不敏感性，并且应证明对相同感兴趣参数具有相似或更好的敏感性水平，并且针对不相关参数的相似或更好的鲁棒性水平。所有方法均应产生定量结果。附录 B 中描述了首选方法和替代方法的基本原理及其缺陷。该标准还提出了适用于涉及基本图像质量参数的 MR 设备质量保证计划的稳定性测试的要求。没有首选的稳定性测试方法来提供使用现有自动化程序（如果可用）的灵活性，但建议的测试方法示例可在附录 A 中找到。如有必要，可以使用本标准中未描述的其他稳定性测试方法。由于责任组织质量保证计划的需求可能会有所不同，因此鼓励责任组织确定必要的测试范围、测试质量和数据分析的敏感性等。该标准强调一致的可重复性、自动化测量有助于趋势分析和对一小组重要参数进行频繁快速测试的工具，这些参数对 MR 设备的整体操作特性敏感。 [外文原描述]： This international standard specifies measurement procedures for the determination of many essential medical MR equipment image quality parameters. Measurement procedures as addressed in this standard are suitable for: - quality assessment in the acceptance test; - quality assurance in the constancy test. In addition, the measurement procedures specified in this standard may also be useful for type tests, although that is not an objective of this standard. The scope of this standard is also limited to measuring image quality characteristics in test devices, not in patient images. The measurement procedures specified in this standard are directed to: a) manufacturers, who can demonstrate compliance by performing acceptance and constancy methods as described by this standard, b) test houses, which can confirm performance of mr equipment using methods described in this standard, c) regulatory authorities, who can reference this standard, and d) responsible organisations who want to perform acceptance and constancy tests using methods described in this standard. The essential image quality parameters and measurement methodologies defined in this standard are: - signal-to-noise ratio, - uniformity, - slice thickness and slice profile, - geometric distortion, - spatial resolution, and - ghosting. This standard describes the preferred measurement procedures. It also describes alternative methods in Annex A. The preferred test methods may be substituted with the alternative methods. If necessary, other methods not described in this standard may be used, provided these other test methods are documented and validated against the methods described in the standard. Validation of other test methods requires an analysis of test sensitivity to the same parameter of interest and an analysis of the insensitivity of the test to other unrelated parameters and should demonstrate a similar, or better, level of sensitivity to the same parameter of interest and a similar, or better, level of robustness against unrelated parameters. All methods shall produce quantitative results. This standard also presents requirements for constancy tests suitable for MR equipment quality assurance programs concerning essential image quality parameters. There are no preferred constancy test methods, to provide flexibility in using existing automated procedures where available, but suggested examples of test methods are found in Annex A. If necessary, other constancy test methods not described in this standard may be used. Since the needs of responsible organisations' quality assurance programs may vary, responsible organisations are encouraged to determine the necessary scope of tests, quality of the tests, and the sensitivity of the data analysis etc. This standard places an emphasis on consistently repeatable, automated measuring tools that facilitate trend analysis and the frequent quick testing of a small set of important parameters which are sensitive to the overall operating characteristics of the mr equipment.