Max Planck Institute for Biological Cybernetics, Spemannstr. 41, Tuebingen 72076, Germany; IMPRS for Cognitive and Systems Neuroscience, Eberhard Karls University of Tübingen, Tübingen, Germany.
Max Planck Institute for Biological Cybernetics, Spemannstr. 41, Tuebingen 72076, Germany; IMPRS for Cognitive and Systems Neuroscience, Eberhard Karls University of Tübingen, Tübingen, Germany.
Neuroimage. 2018 Mar;168:211-221. doi: 10.1016/j.neuroimage.2016.12.065. Epub 2016 Dec 23.
Magnetic resonance spectroscopic imaging (MRSI) is a promising technique for mapping the spatial distribution of multiple metabolites in the human brain. These metabolite maps can be used as a diagnostic tool to gain insight into several biochemical processes and diseases in the brain. In comparison to lower field strengths, MRSI at ultra-high field strengths benefits from a higher signal to noise ratio (SNR) as well as higher chemical shift dispersion, and hence spectral resolution. This study combines the benefits of an ultra-high field magnet with the advantages of an ultra-short TE and TR single-slice FID-MRSI sequence (such as negligible J-evolution and loss of SNR due to T relaxation effects) and presents the first metabolite maps acquired at 9.4T in the healthy human brain at both high (voxel size of 97.6µL) and ultra-high (voxel size of 24.4µL) spatial resolutions in a scan time of 11 and 46min respectively. In comparison to lower field strengths, more anatomically-detailed maps with higher SNR from a larger number of metabolites are shown. A total of 12 metabolites including glutamate (Glu), glutamine (Gln), N-acetyl-aspartyl-glutamate (NAAG), Gamma-aminobutyric acid (GABA) and glutathione (GSH) are reliably mapped. Comprehensive description of the methodology behind these maps is provided.
磁共振波谱成像（MRSI）是一种很有前途的技术，可用于绘制人脑内多种代谢物的空间分布图谱。这些代谢物图谱可用作诊断工具，深入了解大脑中的一些生化过程和疾病。与较低场强相比，超高场强的 MRSI 具有更高的信噪比（SNR）和更高的化学位移弥散度，因此具有更高的光谱分辨率。本研究结合了超高场磁体的优势和超短 TE 和 TR 单回波 FID-MRSI 序列的优势（如由于 T 弛豫效应导致的 J 演化可忽略不计和 SNR 损失），并首次在 9.4T 超高场强下获得了健康人脑的代谢物图谱，在分别为 11 和 46 分钟的扫描时间内，空间分辨率分别达到高（体素大小为 97.6µL）和超高（体素大小为 24.4µL）。与较低场强相比，这些图谱显示出更多具有更高 SNR 的解剖细节更丰富的图谱，可显示更多代谢物。可可靠绘制 12 种代谢物图谱，包括谷氨酸（Glu）、谷氨酰胺（Gln）、N-乙酰天门冬氨酸谷氨酸（NAAG）、γ-氨基丁酸（GABA）和谷胱甘肽（GSH）。为这些图谱提供了全面的方法描述。
