Table 1:
Imaging parameters of the enrolled patients.
| Original 4D-MRI | T1w 3D MRI | T2w 3D MRI | |
|---|---|---|---|
| No. of Patients | 39 | 27 | 27 |
| Contrast-enhanced | No | Yes | No |
| Acquisition mode | Free breathing | Free breathing | Gated |
| Sequence | TWIST-VIBE | Star-VIBE | TSE |
| Fat suppression | N/A | SPAIR | SPAIR |
| Turbo factor | N/A | N/A | 43 |
| Flip angle (°) | 5 | 9 | 72 |
| Echo trains per slice | N/A | N/A | 6 |
| Parallel imaging (factor) | CAIPIRINHA (4) | N/A | GRAPPA |
| Acceleration factor (PE) | 2 | N/A | 3 |
| Partial Fourier | 6/8 | 7/8 | N/A |
| TR (ms) | 3.44 | 2.83 | 1090.0 |
| TE (ms) | 1.23/2.45 | 1.48 | 84.0 |
| Bandwidth (Hz/pixel) | 1420 | 820 | 781 |
| Matrix size | 160 × 128 × 64 | 320 × 320 × 72 | 256 × 256 × 40 |
| Voxel size (mm) | 2.7 × 2.7 × 2.7 | 1.2 × 1.2 × 3.0 | 1.5 × 1.5 × 5.0 |
| Acquisition time | 0.69 s per 3D frame | 173 s | 60 s |
| No. of frames | 72 | N/A | N/A |
3D: Three-dimensional; 4D: Four-dimensional; CAIPIRINHA: Controlled aliasing in parallel imaging results in higher acceleration; GRAPPA: Generalized autocalibrating partial parallel acquisition; MRI: Magnetic resonance imaging; SPAIR: Spectral attenuated inversion recovery; T1w: T1-weighted; T2w: T2-weighted; TE: Echo time; TR: Repetition time; TSE: Turbo spin echo; TWIST: time-resolved imaging with interleaved stochastic trajectories; VIBE: volumetric interpolated breath-hold examination.