Martin Gajdošík1,2, Karl Landheer1, Kelley M. Swanberg1, Fatemeh Adlparvar2, Guillaume Madelin2, Wolfgang Bogner3, Christoph Juchem1,4, and Ivan I. Kirov2,5,6
1Department of Biomedical Engineering, Columbia University, New York City, NY, United States, 2Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York City, NY, United States, 3High-Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria, 4Department of Radiology, Columbia University Medical Center, New York City, NY, United States, 5Department of Neurology, New York University Grossman School of Medicine, New York City, NY, United States, 6Center for Advanced Imaging Innovation and Research, Department of Radiology, New York University Grossman School of Medicine, New York City, NY, United States
1Department of Biomedical Engineering, Columbia University, New York City, NY, United States, 2Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York City, NY, United States, 3High-Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria, 4Department of Radiology, Columbia University Medical Center, New York City, NY, United States, 5Department of Neurology, New York University Grossman School of Medicine, New York City, NY, United States, 6Center for Advanced Imaging Innovation and Research, Department of Radiology, New York University Grossman School of Medicine, New York City, NY, United States
Hippocampal proton MR spectroscopy was
investigated for the feasibility and variability of metabolite concentrations
at long TE of 120 ms, using sLASER localization.
Figure 3: MRS acquisition and spectral analysis. (A)
Placement of the 3.4 mL voxel (26 x 10 x 13 mm3) in the left hippocampus (52
years, woman), containing mainly its body and tail. (B) Spectrum from the
hippocampus fitted with linear combination modelling. Note, no macromolecular
background in the residual signal. (C) Basis set used for quantification of
hippocampal metabolites.
Figure 1: Simplified
simulations of T2 relaxation of normalized signals for macromolecules (MM) and
metabolites. The average T2 relaxation times and ranges of macromolecules and
metabolites were calculated from literature3,14,15. Note that at TE
= 120 ms, most MM signal is gone, while on average 60% of the metabolite signal
remains. This demonstrates that relatively little metabolite signal was lost
while the specific choice of TE = 120 ms enabled easily quantifiable Glu+Gln
(Glx)) and m-Ins resonances.
