• Petra Hnilicová, Michal Považan, Bernhard Strasser, Ovidiu C Andronesi, Martin Gajdošík, Ulrike Dydak, Jozef Ukropec, Dušan Dobrota, Siegfried Trattnig, and Wolfgang Bogner.
• Comenius University in Bratislava, Jessenius Faculty of Medicine in Martin, Biomedical Center Martin, Division of Neurosciences, Martin, Slovakia.
• NMR Biomed. 2016 Nov 1; 29 (11): 1656-1665.

AbstractThe reproducibility of gamma-aminobutyric acid (GABA) quantification results, obtained with MRSI, was determined on a 3 T MR scanner in healthy adults. In this study, a spiral-encoded, GABA-edited, MEGA-LASER MRSI sequence with real-time motion-scanner-instability corrections was applied for robust 3D mapping of neurotransmitters in the brain. In particular, the GABA+ (i.e. GABA plus macromolecule contamination) and Glx (i.e. glutamate plus glutamine contamination) signal was measured. This sequence enables 3D-MRSI with about 3 cm3 nominal resolution in about 20 min. Since reliable quantification of GABA is challenging, the spatial distribution of the inter-subject and intra-subject variability of GABA+ and Glx levels was studied via test-retest assessment in 14 healthy volunteers (seven men-seven women). For both inter-subject and intra-subject repeated measurement sessions a low coefficient of variation (CV) and a high intraclass correlation coefficient (ICC) were found for GABA+ and Glx ratios across all evaluated voxels (intra-/inter-subject: GABA+ ratios, CV ~ 8%-ICC > 0.75; Glx ratios, CV ~ 6%-ICC > 0.70). The same was found in selected brain regions for Glx ratios versus GABA+ ratios (CV varied from about 5% versus about 8% in occipital and parietal regions, to about 8% versus about 10% in the frontal area, thalamus, and basal ganglia). These results provide evidence that 3D mapping of GABA+ and Glx using the described methodology provides high reproducibility for application in clinical and neuroscientific studies.© 2016 The Authors. NMR in Biomedicine published by John Wiley & Sons Ltd.

28 keywords...

hide…