Abstract #3434

Precision & Repeatability of In Vivo GABA & Glutamate Quantification

Ruth L. O'Gorman¹, Richard Edden², Lars Michels¹, James B. Murdoch³, Ernst Martin¹

¹University Children's Hospital, Zrich, Switzerland; ²Russell H. Morgan Department of Radiology & Radiological Sciences, Johns Hopkins University, Baltimore, MD, United States; ³Toshiba Medical Research Institute, Mayfield Village, OH, United States

This study investigates the reliability of GABA and glutamate (Glu) concentrations, derived with MEGA-PRESS and quantified using three different analysis methods. The reliability and sensitivity of the GABA levels are also assessed both with and without metabolite ing to correct for macromolecular contributions to the GABA+ peak at 3 ppm. Overall LCModel provided the best precision for both GABA and Glu. However, the uncorrected LCModel GABA values appear to overestimate the GABA concentrations, although the CRLB values for the LCModel fit were higher for the corrected spectra.