Validation of glutathione quantitation from STEAM spectra against edited 1H NMR spectroscopy at 4T:: application to schizophrenia

Objective: Quantitation of glutathione (GSH) in the human brain in vivo using short echo time H-1 NMR spectroscopy is challenging because GSH resonances are not easily resolved. The main objective of this study was to validate such quantitation in a clinically relevant population using the resolved GSH resonances provided by edited spectroscopy. A secondary objective was to compare several of the neurochemical concentrations quantified along with GSH using LCModel analysis of short echo time spectra in schizophrenia versus control. Materials and Methods: GSH was quantified at 4T from short echo STEAM spectra and MEGA-PRESS edited spectra from identical volumes of interest (anterior cingulate) in ten volunteers. Neurochemical profiles were quantified in nine controls and 13 medicated schizophrenic patients. Results: GSH concentrations as quantified using STEAM, 1.6 +/- 0.4 mu mol/g (mean +/- SD, n = 10), were within error of those quantified using edited spectra, 1.4 0.4 mu mol/g, and were not different (p = 0.4). None of the neurochemical measurements reached sufficient statistical power to detect differences smaller than 10% in schizophrenia versus control. As such, no differences were observed. Conclusions: Human brain GSH concentrations can be quantified in a clinical setting using short-echo time STEAM spectra at 4T.