Abstract:
:A novel multiple quantum filtering method is proposed that uses a doubly selective pulse termed Delays Alternating with Nutations for Tailored Excitation (DANTE) for multiple quantum preparation. This method selectively prepares GABA-3 and GABA-4 into a multiple quantum state and suppresses all other resonances at 3.0 ppm in each single scan. Phantom tests demonstrated excellent GABA signal retention and complete suppression of overlapping metabolites. It is shown using numerical simulations that overlapping macromolecules are suppressed because the frequency of the first upfield 2pi rotation of the doubly selective DANTE pulse coincides with that of the macromolecules at 1.72 ppm. Excellent suppression of overlapping macromolecules was demonstrated in vivo. Using this method the concentration of GABA in the occipital lobe of healthy volunteers was measured to be 1.21 +/- 0.28 micromol/mL (mean +/-SD, N = 9).
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Shen J,Rothman DL,Brown Pdoi
10.1002/mrm.10104subject
Has Abstractpub_date
2002-03-01 00:00:00pages
447-54issue
3eissn
0740-3194issn
1522-2594pii
10.1002/mrm.10104journal_volume
47pub_type
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