Procedures
MR
RECRUITMENT
Before recruitment, all MR scanners were harmonized using phantom studies and adult volunteers, and spectroscopic data were acquired using previously validated cross-platform sequences that can be used in 3T scanners from all 3 common manufacturers.The MR protocol (acquisition time) included 3-dimensional T1- and T2-weighted MR imaging (15 minutes) in the axial and sagittal planes, diffusion tensor imaging (DTI) (7 minutes), proton MR spectroscopic metabolite peak area ratios (PARs) (7 minutes), and metabolite absolute concentrations (13 minutes). We acquired MR spectroscopy in a single 15 × 15 × 15 mm