Caritas St. Elizabeth's Medical Center, Department of Psychiatry, 736 Cambridge St., Boston, MA 02135, USA.
J Magn Reson. 2011 Feb;208(2):210-8. doi: 10.1016/j.jmr.2010.11.003. Epub 2010 Nov 13.
Proton magnetic resonance spectroscopy has the potential to provide valuable information about alterations in gamma-aminobutyric acid (GABA), glutamate (Glu), and glutamine (Gln) in psychiatric and neurological disorders. In order to use this technique effectively, it is important to establish the accuracy and reproducibility of the methodology. In this study, phantoms with known metabolite concentrations were used to compare the accuracy of 2D J-resolved MRS, single-echo 30 ms PRESS, and GABA-edited MEGA-PRESS for measuring all three aforementioned neurochemicals simultaneously. The phantoms included metabolite concentrations above and below the physiological range and scans were performed at baseline, 1 week, and 1 month time-points. For GABA measurement, MEGA-PRESS proved optimal with a measured-to-target correlation of R(2)=0.999, with J-resolved providing R(2)=0.973 for GABA. All three methods proved effective in measuring Glu with R(2)=0.987 (30 ms PRESS), R(2)=0.996 (J-resolved) and R(2)=0.910 (MEGA-PRESS). J-resolved and MEGA-PRESS yielded good results for Gln measures with respective R(2)=0.855 (J-resolved) and R(2)=0.815 (MEGA-PRESS). The 30 ms PRESS method proved ineffective in measuring GABA and Gln. When measurement stability at in vivo concentration was assessed as a function of varying spectral quality, J-resolved proved the most stable and immune to signal-to-noise and linewidth fluctuation compared to MEGA-PRESS and 30 ms PRESS.
质子磁共振波谱有可能提供关于精神和神经疾病中γ-氨基丁酸（GABA）、谷氨酸（Glu）和谷氨酰胺（Gln）改变的有价值信息。为了有效地使用这项技术，重要的是要确定该方法的准确性和可重复性。在这项研究中，使用具有已知代谢物浓度的体模来比较二维 J 分辨 MRS、单回波 30ms PRESS 和 GABA 编辑 MEGA-PRESS 测量上述三种神经化学物质的准确性。体模包括代谢物浓度高于和低于生理范围，扫描在基线、1 周和 1 个月时间点进行。对于 GABA 的测量，MEGA-PRESS 证明是最优的，其测量与目标的相关性 R(2)=0.999，J 分辨提供 GABA 的 R(2)=0.973。所有三种方法都证明在测量 Glu 方面是有效的，R(2)=0.987（30ms PRESS），R(2)=0.996（J 分辨）和 R(2)=0.910（MEGA-PRESS）。J 分辨和 MEGA-PRESS 分别产生了良好的 Gln 测量结果，R(2)=0.855（J 分辨）和 R(2)=0.815（MEGA-PRESS）。30ms PRESS 方法在测量 GABA 和 Gln 方面证明是无效的。当评估作为不同光谱质量函数的体内浓度测量稳定性时，J 分辨被证明比 MEGA-PRESS 和 30ms PRESS 更稳定，对信号噪声和线宽波动更具有免疫力。
