Efficient spectral editing at 7 T: GABA detection with MEGA-sLASER.
At high field (7 T) spectral editing of γ-aminobutyric acid with MEGA-point-resolved spectroscopy is inefficient due to the large chemical shift displacement error. In this article, a new pulse sequence is designed which has minimal chemical shift displacement error to perform an efficient spectral editing of the γ-aminobutyric acid 3.0 ppm resonance at 7 T. The sequence consists of the conventional MEGA editing pulses and a semi-localized by adiabatic selective refocusing sequence. Phantom and in vivo measurements demonstrated an efficient detection of γ-aminobutyric acid. Using ECG triggering, excellent in vivo performance of the MEGA-semi-localized by adiabatic selective refocusing (MEGA-sLASER) provided well-resolved γ-aminobutyric acid signals in 27 mL volumes in the human brain at an echo time of 74 ms within a relatively short acquisition time (5 min). Furthermore, the high efficiency of the MEGA-sLASER was demonstrated by acquiring small volumes (8 mL) at an echo time of 74 ms, as well as long echo time measurements (222 ms in 27 mL volume).
Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands. A.Andreychenko@umcutrecht.nl
Anna
A
Andreychenko
Vincent O
VO
Boer
Catalina S
CS
Arteaga de Castro
Peter R
PR
Luijten
Dennis W J
DW
Klomp
D000465:Algorithms; D001923:Brain Chemistry; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D057054:Molecular Imaging / Q000379:methods*; D011522:Protons; D012815:Signal Processing, Computer-Assisted; D005680:gamma-Aminobutyric Acid / Q000032:analysis*
D011522:Protons; D005680:gamma-Aminobutyric Acid