Nuclear magnetic resonance (NMR) signals with short T1 and T2, such as the 13C signal of glycogen, are difficult to localize in three dimensions without major signal loss. A pulse sequence that accomplishes the spatial localization of 1H-decoupled 13C NMR signals on a whole-body scanner within the Food and Drug Administration guidelines for specific absorption rates was designed. The method uses an optimized three-dimensional outer volume suppression scheme combined with one-dimensional image-selected in vivo spectroscopy and surface coil detection. The localization performance of the sequence was validated at 4 T with double chambered phantoms and 13C magnetic resonance imaging. Localized 13C spectra were acquired from human brain and muscle.
Bibliographical noteFunding Information:
The Center for MR Research is in part supported by a National Center for Research Resources (NCRR) biotechnology research resource grant P41RR08079 and the General Clinical Research Center at the University of Minnesota by NCRR grant M01RR00400. This research was supported by NIH grant R21 NS45519 from the NINDS and NIDDK (RG) and the Juvenile Diabetes Research Foundation International research grant 1-722-2001 (RG).