Table 1.
Sequence parameters
| T2-weighted FSE | Diffusion-weighted MRI | |||
|---|---|---|---|---|
| DWIBS | DWI-SPIR | DWI-SPAIR | ||
| Repetition time | 8456–9558 | 4808–4829 | 4971 | 4172–5241 |
| Echo time | 130–150 | 70 | 70 | 68–70 |
| Number of slices | 22–30 | 50 | 24 | 20–24 |
| Slice thickness (mm) | 3–5 | 5 | 5 | 5 |
| FOV (mm) | 200 | 440 | 320 | 320 |
| Acquired in plane resolution (mm × mm) | 0.78 × 1.14 | 2.50 × 3.11–3.18 | 1.82 × 2.31 | 1.82 × 2.27 |
| Sensitivity encoding factor | – | 1.9–2 | 1.9 | 1.9 |
| Echotrain length | 25 | 1 | 1 | 1 |
| Number of signal averages | 2–6 | 4 | 5 | 5 |
| Acquisition time (min:sec) | 4:37–6:30 | 10:37–12:20 | 05:33 | 05:51–06:44 |
| B-values | – | 0, (100), 500, 1000 | 0, 500, 1000 | 0, (25, 50, 100) 500,1000 |
| Fatsuppression technique | – | STIR | SPIR | SPAIR |
| Echo planar imaging factor | – | 53–55 | 55 | 61 |
Abbreviations: STIR short TI inversion recovery, SPIR spectral presaturation with inversion recovery, SPAIR spectral attenuated inversion recovery. During the study period, the DWIBS sequence was applied from September 2008 through December 2011, the DWI-SPIR sequence was used from December 2011 through June 2012, and the DWI-SPAIR sequence was used from June 2012 through the end of the study period (July 2014)