Abstract:
:Metabolite signals with short T(1) or T(2) are difficult to localize with full sensitivity. This limitation was overcome with the development and implementation of a single-shot, complete three-dimensional "non-echo" localization method with reduced sensitivity to spatial B(1) variation, which is suitable for measuring signals with very short T(1) or T(2), e.g., the (13)C NMR signals of glycogen. The proposed method is based on a T(1)-optimized outer volume suppression scheme using pulses of the hyperbolic secant type applied at different power levels, which is robust over a fivefold range of T(1). Strong lipid, muscle glycogen, and glucose signals originating outside the rat brain were suppressed. Signals of glycogen, aspartate, glutathione, GABA C4, N-acetyl aspartate as well as the C3 and C4 signals of glutamate and glutamine with resolved homonuclear (13)C-(13)C coupling were fully resolved in vivo at 9.4 Tesla using higher-order shimming. The method can be extended to other nuclei and to localized MRS of humans.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Choi IY,Tkác I,Gruetter Rdoi
10.1002/1522-2594(200009)44:3<387::aid-mrm8>3.0.cosubject
Has Abstractpub_date
2000-09-01 00:00:00pages
387-94issue
3eissn
0740-3194issn
1522-2594pii
10.1002/1522-2594(200009)44:3<387::AID-MRM8>3.0.COjournal_volume
44pub_type
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