title: Very short echo time improves the precision of glutamate detection at 3T in 1H magnetic resonance spectroscopy.
abstract: OBJECTIVE
  To examine the precision of glutamate detection using a very short echo time (TE) phase rotation STEAM (PR-STEAM) sequence.
  
  
  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%).
  
  
  CONCLUSIONS
  In the absence of spectral editing, glutamate is best detected in the human brain at 3T using very short TEs.
authors.affiliation: Department of Radiology, Children's Healthcare of Atlanta, Atlanta, Georgia 30322, USA.
authors.forename: S Andrea
authors.initials: SA
authors.lastname: Wijtenburg
authors.forename: Jack
authors.initials: J
authors.lastname: Knight-Scott
mesh_terms: D000328:Adult; D000465:Algorithms; D018698:Glutamic Acid / Q000032:analysis*; D006179:Gyrus Cinguli / Q000737:chemistry*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008875:Middle Aged; D011522:Protons; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D011522:Protons; D018698:Glutamic Acid