Table 1.
MRI Protocol at the First (Baseline) Survey.
| Sequence (Data type) | Measured property and commentary | Sequence parameters | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Representative images (number of participants) | Acquisition & slice | TR (ms) | TE (ms) | Inversion time (ms) | SENSE: AP RL |
b-value (s/mm2) | FOV (mm) | Matrix | Slice thickness (mm) | FA (degrees) | Acquisition time (s) | ||
| T1-weighted imaging (T1WI) (29) | Brain structures obtained by magnetization prepared-rapid gradient echo (MP-RAGE) | 12,164 | 3D Sagittal |
11 | 5.2 | 1068.3 | 2 2.5 |
N/A | 256 | 368 × 368 | 0.7 | 8 | 319 |
| Magnetic resonance angiography (MRA) (30) | Brain vascular structure | 12,050 | 3D Axial |
25 | 3.5 | 0 | 1(FH) 3 |
N/A | 200 | 384 × 249 | 1.1 | 18 | 247 |
| Diffusion tensor imaging (DTI) (31) | Interaction or connection of white matter fascicles in the brain | 10,443 | 2D Axial |
7173 | 83 | 0 | 2.5 N/A |
800 (32)2 |
224 | 112 × 112 | 2 | 90 | 318 |
| Pseudo-continuous arterial spin-labeling (pCASL)(32) | Cerebral blood flow1 | 10,461 | 2D Axial |
4023 | 11 | 0 | 2.1 N/A |
N/A | 240 | 64 × 64 | 7/1 | 90 | 247 |
| Fluid-attenuated inversion recovery (FLAIR) (33) | White matter lesions (collected in those aged >50 years only) | 2,428 | 3D Sagittal |
4800 | 276 | 1650 | 3 3.2 |
N/A | 256 | 212 × 212 | 1.2 | 90 | 264 |
Notes:
Parenthesized numerical references correspond to bibliographic citations elsewhere in the manuscript.
TR: repetition time, TE: echo time, SENSE: sensitivity encoding, FOV: field of view, FA: flip angle.
D: Dimension, AP: anterior and posterior directions, RL: right and left directions, FH: foot and head direction
N/A: Not applicable
TR, TE, and Inversion time could be variable according to the slice angle.
1 Post-labeling delay: 1,800 ms
2 The number in parentheses is the number of diffusion directions.