This review on brain multiparametric quantitative MRI (MP-qMRI) focuses on the primary subset of quantitative MRI (qMRI) parameters that represent the mobile (“free”) and bound (“motion-restricted”) proton pools. Such primary parameters are the proton densities, relaxation times, and magnetization transfer parameters. Diffusion qMRI is also included because of its wide implementation in complete clinical MP-qMRI application. MP-qMRI advances were reviewed over the past 2 decades, with substantial progress observed toward accelerating image acquisition and increasing mapping accuracy. Areas that need further investigation and refinement are identified as follows: (a) the biologic underpinnings of qMRI parameter values and their changes with age and/or disease and (b) the theoretical limitations implicitly built into most qMRI mapping algorithms that do not distinguish between the different spatial scales of voxels versus spin packets, the central physical object of the Bloch theory. With rapidly improving image processing techniques and continuous advances in computer hardware, MP-qMRI has the potential for implementation in a wide range of clinical applications. Currently, three emerging MP-qMRI applications are synthetic MRI, macrostructural qMRI, and microstructural tissue modeling.

© RSNA, 2022

这篇关于脑多参数定量 MRI (MP-qMRI) 的综述重点关注代表移动（“自由”）和束缚（“运动限制”）质子池的定量 MRI (qMRI) 参数的主要子集。这些主要参数是质子密度、弛豫时间和磁化传递参数。扩散 qMRI 也被包括在内，因为它在完整的临床 MP-qMRI 应用中得到了广泛的应用。对过去 20 年 MP-qMRI 的进展进行了回顾，在加速图像采集和提高绘图精度方面观察到了实质性进展。需要进一步研究和完善的领域确定如下：(a) qMRI 参数值的生物学基础及其随年龄和/或疾病的变化；(b)隐含在大多数 qMRI 映射算法中的理论局限性，这些算法不区分体素与自旋包的不同空间尺度，是布洛赫理论的核心物理对象。随着图像处理技术的快速改进和计算机硬件的不断进步，MP-qMRI 具有在广泛的临床应用中实施的潜力。目前，三种新兴的 MP-qMRI 应用是合成 MRI、宏观结构 qMRI 和微观结构组织建模。

© 北美放射学会，2022