Very short echo time improves the precision of glutamate detection at 3T in 1H magnetic resonance spectroscopy.

Purpose: To examine the precision of glutamate detection using a very short echo time (TE) phase rotation STEAM (PR-STEAM) sequence.

Materials And Methods: 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.

Results: 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%).

Conclusion: In the absence of spectral editing, glutamate is best detected in the human brain at 3T using very short TEs.