Ge hdx 3t scanner

A GE HDx 3 T scanner (GE Healthcare, Milwaukee WI) was used for all MRI acquisition. An axial 3D fast spoiled gradient recalled (FSPGR) sequence was acquired (TR/TE/TI = 8/3/ 450 ms; Flip Angle = 20°; acquisition matrix = 256(AP)x192(LR)x172(SI), 1 mm isotropic voxels) for MEG co-registration.

MRI imaging for both samples (case–control and ALSPAC) was performed on the same GE HDx 3T scanner (GE Healthcare, Milwaukee WI) at Cardiff University Brain Research Imaging Centre. A T1-weighted brain scan was acquired for co-registration by an axial three-dimensional fast spoiled gradient recalled sequence (repetition time (TR)/echo time (TE)/inversion time (TI) = 8/3/450 ms; flip angle 20°; acquisition matrix 256(anterior–posterior) × 192(left–right) × 172(superior–inferior), 1 mm isotropic voxels), followed by a diffusion tensor imaging (DTI) sequence with a twice-refocused spin-echo echo-planar parallel to the AC-PC plane. Acquisition was peripherally gated to the cardiac cycle. Data were obtained from 60 slices of 2.4 mm thickness (field of vision 230 mm, matrix size 96 × 96, TE = 87 ms and parallel imaging (Array coil Spatial Sensitivity Encoding Technique (ASSET) factor 2), b-values 0 and 1200 s/mm²), encoding diffusion along 30 isotropically distributed directions and three non-diffusion-weighted scans according to an optimised gradient vector scheme.³⁰ (link) Part of the ALSPAC sample (n = 219) was acquired as 60 directions, of which the optimal 30 directions were selected³¹ (link) together with the first three b-value 0 images, to make this data-set equivalent to the above and to allow for joint processing of all data.