Department of Radiology, Children's Healthcare of Atlanta, Atlanta, Georgia 30322, USA.
J Magn Reson Imaging. 2011 Sep;34(3):645-52. doi: 10.1002/jmri.22638. Epub 2011 Jul 14.
To examine the precision of glutamate detection using a very short echo time (TE) phase rotation STEAM (PR-STEAM) sequence.
Spectrosopic data were acquired from the anterior cingulate gyrus in nine healthy adults using 6.5-msec TE PR-STEAM, 40-msec TE PRESS, 72-msec TE STEAM, and TE-Averaging with an effective TE of 105 msec on a clinical 3T magnetic resonance imaging (MRI) system. All data were quantified using LCModel and reported as ratios relative to total creatine.
Glutamate Cramer-Rao lower bounds were less than 8% for all sequences. The 6.5-msec TE PR-STEAM identified glutamate with the greatest precision (coefficient of variation [CV] of 7.1%), followed by TE-Averaging (CV of 8.9%), 40-msec TE PRESS (CV of 11.9%), and 72-msec TE STEAM (CV of 13.8%).
In the absence of spectral editing, glutamate is best detected in the human brain at 3T using very short TEs.
探究使用超短回波时间（TE）相位旋转刺激回波采集（PR-STEAM）序列检测谷氨酸的精度。
使用临床 3T 磁共振成像（MRI）系统，对 9 名健康成年人的前扣带回进行光谱数据采集，采用的序列有 6.5ms TE PR-STEAM、40ms TE PRESS、72ms TE STEAM 和 TE 平均（有效 TE 为 105ms）。所有数据均使用 LCModel 进行定量分析，并以相对总肌酸的比值进行报告。
所有序列的谷氨酸 Cramer-Rao 下限均小于 8%。6.5ms TE PR-STEAM 检测谷氨酸的精度最高（变异系数[CV]为 7.1%），其次是 TE 平均（CV 为 8.9%）、40ms TE PRESS（CV 为 11.9%）和 72ms TE STEAM（CV 为 13.8%）。
在没有谱编辑的情况下，在 3T 场强下，使用超短 TE 可最佳检测人脑内的谷氨酸。
