Table 1:
Imaging parameters for ungated QISS and CE-MRA sequences
| Parameter | Ungated QISS-MRA | CE-MRA |
|---|---|---|
| Imaging mode | 2D | 3D |
| FLASH TR/TE (ms) | 15.0/4.7 | 3.09/1.2 |
| QISS sequence TR (ms) | 1100.8 | – |
| Acquisition matrix (Px) | 384 × 384 | 512 × 512 |
| Acquisition pixel (mm2) | 0.5 × 0.5 | 0.6 × 0.6 |
| In-plane interpolation | On | On |
| Slice thickness (mm) | 2.0 | 1.0 |
| No. of slices | 128 | 80 |
| Slice distance factor (%) | −33 | 20 |
| No. of averages | 1 | 1 |
| Receiver bandwidth (Hz/Px) | 303 | 540 |
| Flip angle | 30° | 30° |
| Slice orientation | Tilted transversal to coronal (45° tilt) | Coronal |
| K-space trajectory | Radial | Cartesian |
| No. of radial projections | 204 | – |
| No. of shots per slice | 3 | – |
| Phase oversampling (%) | 0 | 40 |
| Filter | Distortion correction (2D); prescan normalizer | Distortion correction (3D); prescan normalizer |
| B0 shim mode | Heart | Tune-up |
| Asymmetric echo | Off | On |
| RF pulse type | Normal | Normal |
| Gradient mode | Fast | Fast |
| RF spoiler | On | On |
| iPAT modus (acceleration factor/No. of reference lines) | – | 2/24 |
| Partial Fourier (phase and slice) | – | 6th/8th |
| Venous saturation slab thickness (mm) | 100 | – |
| Distance between venous saturation and imaging slab (mm) | 10 | – |
| TI (ms) | 530 | – |
| Acquisition time (min:sec) | 7:03 | 0:20 |
Note:—iPAT indicates integrated parallel imaging technique; TI, time from in-plane and venous saturation to the acquisition of central k-space (ky = 0); Px, pixel; –, sequence parameter is not available; TR, repetition time; TE, echo time; RF, radiofrequency; Hz, Hertz.