Test-Retest Precision of Brain Metabolites in Healthy Participants using 31P-MRS and 1H MEGA-PRESS at 3T Multi-nuclear MRI System

Motivation: MRS enables non-invasive quantification of brain metabolites, but its reliability is crucial for accurate interpretation. Goal(s): This study assessed the test-retest of 31P-MRS and 1H-MEGA-PRESS in measuring phosphorus-31 metabolites, GABA, GSH using a 3T system. Approach: 32 participants underwent two scanning sessions within three days. GABA+, Glx, GSH, and ten 31P metabolites were analyzed based on CV and Bland-Altman plots. Results: The CV of GPE, GPC, -ATP, -ATP, pH and Mg2+ was below 10%, PE, PC, -ATP, Pi, GPTC was over 10%. The CV of GABA+/Cr, GABA+/water, Glx/Cr, Glx/water were below 4%; GSH/Cr, GSH/water were 11.904% and 16.525%. Impact: This study reveals the range of reliability of MEGA-edited GABA+, Glx and 31P-MRS techniques in application.