Table 1.
Imaging Parameters used for Ungated Nonenhanced QISS FISS MRA
| Parameter | Pelvic MRA | Carotid MRA | Intracranial MRA |
|---|---|---|---|
| FISS TRf (ms) | 17.6 | 17.3 | 10.7 |
| TRb (ms) | 3.8 | 3.9 | 4.0 |
| TE (ms) | 1.9 | 1.9 | 2.0 |
| Flip angle (°) | 70 | 70 | 67 |
| FISS n | 3 | 3 | 1 |
| FISS RF spoiling | yes | no | no |
| QISS TI (ms) | 1600 | 505 | 400 |
| Field of view (mm × mm) | 400 × 400 | 256 × 256 | 256 × 256 |
| Reconstructed Matrix | 384 × 384 | 256 × 256 | 256 × 256 |
| rn, radial views | 147/441a | 132 | 192 |
| rθ, view angle increment (°) | 15.918/15.102a | 17.727 | 15.938 |
| Radial undersampling factorb | 4.1/1.4a | 3.0 | 2.1 |
| Slice thickness (mm) | 3 | 3 | 1 |
| Slice overlap (mm) | – | 1.5 | 0.5 |
| Imaging shots per slice | 1/3a | 1 | 4 |
| Bandwidth (Hz/pixel) | 930 | 930 | 975 |
| Number of slices | 120 | 120 | 120 |
| Scan time (per slice) | 2.07/6.21 sa | 1.01 s | 2.58 s |
| Scan time (total) | 9 min 40 s | 2 min 1 s | 5 min 10 s |
| FISS Gspoil duration (ms) | 1.4 | 5.1 | – |
| FISS Gspoil strength (mT/m) | 7.8 | 7.8 | – |
a
Values provided in the form: lower 40 slices / upper 80 slices.
b
With respect to satisfying the Nyquist sampling requirements. FISS Gspoil refers to an additional gradient applied between FISS modules (slice axis). n=number of bSSFP views acquired per FISS module; QISS=quiescent-interval slice-selective; TI=inflow time. Field of view and matrix values are after removal of oversampling in readout direction and without zero-filling interpolation.