Diffusion-weighted images (DWIs) were collected on 3 Tesla GE Echospeed system (General Electric Medical Systems, Milwaukee, WI). DWIs were acquired using an echo-planar imaging sequence, and a double echo option to reduce eddy-current related distortions. To reduce impact of EPI spatial distortion, an 8-Channel coil and ASSET (Array Spatial Sensitivity Encoding techniques, GE) with a SENSE-factor (speed-up) of 2 was used. Eighty-five axial slices parallel to the AC-PC line covering whole brain were acquired, in 51 diffusion directions with b=900 s/mm2. 8 baseline scans with b=0 were also acquired. The scan parameters were: TR 17000 ms, TE 78 ms, FOV 24 cm, 144×144 matrix, 1.7 mm slice thickness, producing isotropic 1.7×1.7×1.7 mm voxels. The total scanning time was approximately 17 minutes.
