Table 1.
MRE protocol. Synoptic table summarizes the scanning parameters of MR pulse sequences. Coronal T1-weighted 3D gradient-echo liver acquisition with volume acceleration (LAVA) sequences with fat suppression were acquired before and after intravenous administration of paramagnetic contrast material (0.1 mmol/kg, followed by 20 mL of saline solution, both at a flow rate of 2 mL/s); in particular, the sequence was acquired at 60 and 120 s after contrast administration. An anti-peristaltic agent, scopolamine-N-butyl bromide (Buscopan® 20 mg; Boehringer Ingelheim, Milano, Italy), was administered intravenously just before post-contrast imaging to reduce peristaltic artifacts.
| MRI Protocol | Coronal T2W SSFSE | Coronal FIESTA | Coronal T2W Thick-slab SSFSE | Axial DWI SE EPI | Sagittal, Coronal, Axial T1W 3D GRE LAVA |
|---|---|---|---|---|---|
| Repetition time/Echo time (ms) | 705/90 | 4/1.7 | 2408/1103 | 3000/74 | 4.1/1.9 |
| Flip angle | 90° | 75° | 90° | 90° | 12° |
| Section Thickness (mm) | 6 | 6 | 70 | 8 | 3.4 |
| Interslice gap (mm) | 0.6 | 0.6 | — | 2 | 1.7 |
| Bandwidth (kHz) | 83.33 | 100 | 31.25 | 250 | 62.5 |
| Field of view (cm) | 44–48 | 44–48 | 44–48 | 42 | 44–48 |
| Matrix | 384 × 224 | 512 × 384 | 512 × 384 | 160 × 160 | 320 × 192 |
| N. of signal acquired | 0.57 | 1 | 1 | 2 | 0.7 |
| N. of images | 28 | 28 | 1 | 15 | 120 |
| Frequency direction | Right to left | Right to left | Right to left | Anterior to posterior | Superior to inferior |
| Acquisition time (s) | 24 | 22 | 2 | 27 | 23 |
| B-value (s/mm2) | — | — | — | 0–800 | — |
T2W = T2-weighted, T1W = T1-weighted, SSFSE = single-shot fast spin-echo, FIESTA = fast imaging employing steady-state acquisition, DWI = diffusion-weighted imaging, SE = spin-echo, EPI = echoplanar imaging, GRE = gradient-echo, LAVA = liver acquisition with volume acceleration.