3t verio mr scanner

An anatomical 3D T1-weighted MP-RAGE sequence with matrix size = 256 × 256 × 192; voxel size = 1 × 1 × 1 mm; TR/TE/TI = 1550/3.04/800 ms; flip angle = 9° was acquired for all patients using a Siemens Magnetom Trio 3T MR scanner or a Siemens 3T Verio MR scanner. In addition, a 3D T2-weighted isotropic sagittal sequence with matrix size 256 × 256 × 176; voxel size = 1 × 1 × 1 mm; TR/TE = 3200/409 ms; flip angle = 120° was also acquired for all subjects. All single-subject MRI sequences were corrected for gradient nonlinearities according to Jovicich et al. 2006 (link), in order to correct for spatial distortions and achieve optimal PET-MR co-registration. All the acquired MR images were examined for structural abnormalities, as a criterion for subject inclusion.

Participants completed a 10-minute rs-fMRI scan (280 volumes) acquired on a Siemens (Erlangen, Germany) 3T Verio MR scanner. During rs-fMRI scans, participants were instructed to close their eyes, but not to fall asleep. The participants were asked after the scan whether they fell asleep during the scan; all participants reported not falling asleep. Scans were acquired using a T2*-weighted gradient echo-planar imaging (EPI) sequence sensitive to blood-oxygen level dependent (BOLD) signal (TR=2.15 s, TE=26 ms, flip-angle=78°, in-plane matrix 64x64, number of slices=42, voxel size=3x3x3 mm, GRAPPA acceleration factor 2, no gap, interleaved slice order). Pulse and respiratory data were sampled at 50 Hz using the Siemens' Physiological Monitoring Unit.
A high-resolution 3D T1-weighted structural image was acquired using a sagittal, magnetization prepared rapid gradient echo (MP-RAGE) sequence (TE/TR/TI=2.32/1900/900 ms, flip angle=9°, in-plane matrix 256x256, number of slices=224, voxel size=0.9x0.9x0.9 mm, GRAPPA acceleration factor 2, no gap, acquisition time = 8 min 30 sec). A high-resolution 3D T2-weighted image was acquired using a sagittal, Turbo Spin Echo (TSE) scan of the whole head (TE/TR= 409/3200 ms, flip angle=120º, in-plane matrix 256x256, number of slices=176, voxel size=1x1x1 mm, GRAPPA acceleration factor 2, acquisition time = 4 min 43 sec).