ABCD MRI Structural Imaging Protocol

Details of the ABCD magnetic resonance imaging (MRI) protocol have been described previously [73 (link)]. Briefly, imaging data were collected on either a Siemens Prisma, Phillips, or GE 750 3T scanner using 32-channel head or 64-channel head/neck coils. T1-weighted scan parameters were as follows: Siemens - matrix size 256 × 256, 176 slices, FOV 256 × 256, resolution (mm) 1 × 1 × 1, TR 2500 ms, TE 2.88 ms, flip angle 8°, total scan time 7:12; Phillips - matrix size 256 × 256, 225 slices, FOV 256x240, resolution (mm) 1 × 1 × 1, TR 6.31 ms, TE 2.9 ms, flip angle 8°, total scan time 5:38; and GE - matrix size 256 × 256, 208 slices, FOV 256 × 256, resolution (mm) 1 × 1 × 1, TR 2500 ms, TE 2 ms, flip angle 8°, total scan time 6:09.
Tabulated data representing T1-weighted measurements of subcortical volume (VOL), cortical thickness (CT), and surface area (SA) as derived from the Desikan parcellation atlas [34 (link)] in FreeSurfer v5.3 (http://surfer.nmr.mgh.harvard.edu/) were downloaded from the NDA. ABCD-recommended imaging inclusion criteria were followed to ensure the inclusion of high-quality MRI scans, and this excluded participants with serious MR findings and participants whose T1-weighted images or FreeSurfer parcellations failed to pass ABCD DAIC quality control. Regional MRI metrics were averaged across hemispheres.