MRI Engineering Core, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA.
Medical Physics, Department of Radiology, Faculty of Medicine, University Freiburg, Freiburg, Germany.
J Magn Reson Imaging. 2023 Jan;57(1):57-70. doi: 10.1002/jmri.28421. Epub 2022 Sep 8.
In magnetic resonance imaging (MRI), spatial field gradients are applied along each axis to encode the location of the nuclear spin in the frequency domain. During recent years, the development of new gradient technologies has been focused on the generation of stronger and faster gradient fields for imaging with higher spatial and temporal resolution. This benefits imaging methods, such as brain diffusion and functional MRI, and enables human imaging at ultra-high field MRI. In addition to improving gradient performance, new technologies have been presented to minimize peripheral nerve stimulation and gradient-related acoustic noise, both generated by the rapid switching of strong gradient fields. This review will provide a general background on the gradient system and update on the state-of-the-art gradient technology. EVIDENCE LEVEL: 5 TECHNICAL EFFICACY: Stage 1.
在磁共振成像(MRI)中,沿每个轴施加空间磁场梯度,以在频率域中对核自旋的位置进行编码。近年来,新梯度技术的发展一直集中在生成更强和更快的梯度场,以实现更高空间和时间分辨率的成像。这有利于成像方法,如脑扩散和功能 MRI,并使超高强度 MRI 能够进行人体成像。除了提高梯度性能外,还提出了新技术来最小化外周神经刺激和梯度相关的声噪声,这两种噪声都是由强梯度场的快速切换产生的。本综述将提供梯度系统的一般背景知识,并介绍最新的梯度技术。证据水平:5 技术功效:第 1 阶段。