Bucher S F, Seelos K C, Stehling M K, Oertel W H, Reiser M
Neurologische Klinik und Poliklinik, Ludwig-Maximilians-Universität München, Klinikum Grosshadern.
Radiologe. 1995 Apr;35(4):228-36.
The techniques of in vivo functional magnetic resonance imaging (fMRI) have been established over the past few years. Signal changes resulting from small differences in the magnetic resonance signal caused by variations in the oxygenation state of the venous vasculature are used to map neuronal activity of the brain. While many of the advantages for using MRI for functional neuroimaging are quite obvious (high spatial and temporal resolution, direct anatomic correlation, noninvasiveness), the underlying mechanisms and problems are not fully known. This article focuses on selected topics of fMRI techniques and their problems, such as field strength B0, different types of sequences and their parameters, 2D and 3D data acquisition, different statistical methods and motion artifacts. The authors favor the use of a 1.5 T clinical scanner with EPI capabilities, 2D FLASH sequences with a TR < 60 ms, TE = 30-40 ms, alpha < 20 degrees for high resolution and sensitivity, fMRI and multislice EPI for high temporal and overview and fMRI as well as cross-correlation for post-processing.
在过去几年中，体内功能磁共振成像（fMRI）技术已经确立。静脉血管系统氧合状态变化引起的磁共振信号微小差异所导致的信号变化，被用于绘制大脑的神经元活动图。虽然使用MRI进行功能神经成像的许多优点相当明显（高空间和时间分辨率、直接解剖关联、非侵入性），但其潜在机制和问题尚未完全明确。本文重点关注fMRI技术的选定主题及其问题，如场强B0、不同类型的序列及其参数、二维和三维数据采集、不同的统计方法以及运动伪影。作者倾向于使用具有EPI功能的1.5T临床扫描仪、TR < 60 ms、TE = 30 - 40 ms、α < 20度的二维FLASH序列以实现高分辨率和高灵敏度，使用fMRI和多层EPI以实现高时间分辨率和全景成像，以及使用fMRI和互相关进行后处理。
