Wolfgang Bogner1, Marek Chmelik1,
Ovidiu Cristian Andronesi2, Stephan Gruber1, Siegfried
1MR Center of Excellence, Radiology, Medical
University, Vienna, Austria; 2Martinos Center for Biomedical
Imaging, Radiology, Massachusetts General Hospital, Havard Medical School,
Charlestown, MA, United States
image-selected in vivo spectroscopy (ISIS)
sequence was developed for acquisition of localized 31P-MRS at 7T in vivo.
For accurate localization (negligible contamination and chemical shift error)
even with B1 inhomogeneous surface coils gradient offset independent
adiabatic (GOIA) inversion pulses with high bandwidth were used. To allow
short TR without increases in contamination due to T1 smearing an E-ISIS
acquisition scheme was combined with adiabatic BIR-4 excitation. This allows
localized 31P-MRS in clinically feasible measurement time (~3-4 min) and good
spatial resolution (~2-2.5 cm isotropic) with high reproducibility.