Table 1.
Sequence Parameters.
| 3T | 7T | |||||||
|---|---|---|---|---|---|---|---|---|
| IR-SWIET1 | DIR2 | MP2RAGE3 | T2*wEPI4 | FLAIR5 | PSIR6 | MP2RAGE | T2*w GRE7 | |
| Orientation | Sagittal | Sagittal | Sagittal | Sagittal | Sagittal | Axial | Axial | Axial |
| 2D vs 3D | 3D | 3D | 3D | 3D | 3D | 2D | 3D | 2D |
| Voxel dimensions (mm) | 0.8x0.8 (reconstructed at 0.64x0.64) | 1.2x1.2 | 1x1 | 0.54x0.57 | 1x1 | 0.5x.0.53 | 0.5x0.5 | 0.5x0.5 |
| Slice thickness (mm) | 0.64 | 0.65 | 1 | 0.55 | 0.76 | 2 | 0.50 | 0.50 |
| FOV | 245 (SI) x229 (AP) x 160 (RL) | 250 (SI) x 250 (AP) x 167 (RL) | 256 (SI) x240 (AP) x176 (RL) | 240 (SI) x 240 (AP) x 168 (RL) | 224 (SI) x 224 (AP) x 237 (RL) | 240 (AP) x 239 (RL) x 110 (SI) | 224 (AP) x 168 (RL) x112 (SI) | 240 (AP) x 168 (RL) x30 (SI) |
| TI (ms) | 2650 | 2550/450 | 700/2500 | NA | 1650 | 400 | 800/2700 | NA |
| TR/TE (ms) | 58/32 | 5500/203 | 5000/2.9 | 54/29 | 4800/321 | 10010/17 | 6000/5 | 4095/11.4, 22.5, 33.6, 44.7, 55.8 |
| Flip angle (°) | 12 | 90 | 4/5 | 10 | 90 | 90 | 4/5 | 70 |
| Scan time (min:sec) | 5:08 | 10:44 | 8:16 | 4:15 | 4:55 | 8:30 | 10:32 (median of 4 acquisitions analyzed) | 11:26 per volume x3 for full supratentorial coverage |
1
Inversion recovery susceptibility weighted imaging with enhanced T2 weighting,
2
Double inversion recovery,
3
Magnetization-prepared 2 rapid gradient echo,
4
T2* weighted segmented echo-planar imaging,
5
Fluid-attenuated inversion recovery,
6
Phase-sensitive inversion recovery.
FOV – field of view, TI – inversion time, TR – repetition time, TE – echo time.