Fast MPF mapping protocol parametersa
| Parameter | 3D MT-Weightedb and Reference GRE | 3D T1-Weighted GRE | 3D PD-Weighted GRE |
|---|---|---|---|
| TR (ms) | 32 | 20 | 20 |
| TE (ms) | 6.3 (6.1) | 6.3 (6.1) | 6.3 (6.1) |
| Flip angle | 8° | 20° | 4° |
| FOV (mm2) | 250 × 250 (240 × 200) | 250 × 250 (240 × 200) | 250 × 250 (240 × 200) |
| Acquired/reconstructed in-plane resolution (mm2) | 1.5 × 1.5/0.8 × 0.8 | 1.5 × 1.5/0.8 × 0.8 | 1.5 × 1.5/0.8 × 0.8 |
| Acquired/reconstructed section thickness (mm) | 5/2.5 | 5/2.5 | 5/2.5 |
| No. of acquired reconstructed sections | 12/24 (40/80) | 12/24 (40/80) | 12/24 (40/80) |
| EPI factor | 9 | 9 | 9 |
| No. of averages | 2 | 2 | 2 |
| Acquisition time (min:sec) | 0:38 (1:55) | 0:12 (0:36) | 0:12 (0:36) |
Note:—PD indicates proton density.
↵a Data in parentheses correspond to the parameters for adult brain scans if different from fetal ones.
↵b Standard manufacturer's off-resonance saturation pulse (3-lobe sinc shape with Gaussian apodization) with the offset frequency of 1.1 kHz, effective flip angle of 520°, and duration of 15 ms was used in the MT-weighted sequence. Acquisition time includes both MT-weighted and reference images, which were sequentially acquired in a single scan using a standard manufacturer's option.