Table 1.
MRI parameters used in the current study
| MRI sequence | TR/TE (ms) | FOV (mm) | Resolution (mm) | Matrix | Flip angle | Slice thickness (mm) |
|---|---|---|---|---|---|---|
| Sagittal T2W TSE | 2659/120 | 140 | 0.46 × 0.6 × 3.0 | 304× 234 | 90 | 3 |
| Axial T2W TSE | 4434/120 | 140 | 0.46 × 0.6 × 3.0 | 304× 234 | 90 | 3 |
| Coronal T2W TSE | 2174/120 | 140 | 0.46 × 0.6 × 3.0 | 304× 234 | 90 | 3 |
| Axial DW MRIa | 5770/52 | 160 | 1.25 × 1.25 × 3.0 | 112× 108 | 90 | 3 |
| 3D MR PRESSb | 980/100 | 72 | 6.0 × 6.0 × 6.0 | 10× 10 | 90 | 6 |
| Axial pre-contrast T1 | 5.5/2.1 | 260 | 0.86 × 1.18 × 6.0 | 256× 186 | 5 | 6 |
| Axial 3D DCEc | 5.5/2.1 | 260 | 0.86 × 1.18 × 6.0 | 188× 96 | 15 | 6 |
FOV, field of view; TE, echo time; TR, repetition time; TSE, turbo spin echo.
aAxial DW multi-slice images with 20 slices taken with 5 evenly spaced B values from 0 to 750 s/mm2 and ADC maps were calculated.
b3D MR point resolved spectroscopy; water and fat signals were suppressed before data collection; each spectrum (1024 complex points) was obtained from a voxel size of 6 × 6 × 6 mm3 tissue with spectral width of 2000 Hz. Second-order shimming was used to maximize magnetic field homogeneity in the localized volume.
cAxial DCE images before, during, and after a single-dose injection of gadopentetate dimeglumine (Magnevist, Berlex, Wayne, NJ, USA) at a dose of 0.1 mmol/kg through a peripheral vein at a rate of 3 ml/s via a mechanical injector (Spectris MR Injection System, Medrad, Pittsburgh, PA, USA). The DCE acquisition consisted of a 10-slice, 3D T1W fast-field echo with a phase encoding direction from left to right without fat saturation. Four unenhanced sets (13 s) and approximately 96 contrast-enhanced sets of images were acquired sequentially without a delay between acquisitions. A total of 1000 images were obtained during DCE MRI (temporal resolution = 3.1 s).