Table 1 Pfirrmann grading system of IVD on T2WI
From: Biochemical changes in lumbar facet joint and disc degeneration by T2* mapping
Grade | Signal intensity of nucleus pulposus and inner fibrosus | Signal difference between rear, inner and outer fibrosis | IVD height |
|---|---|---|---|
1 | Uniform high signal (nearly equal to CSF) | Obvious | Normal |
2 | High signal (higher than presacral fat, but lower than CSF) | Obvious | Normal |
3 | High signal (cracks in the nucleus pulposus observed) | Obvious | Normal |
4 | High signal (lower than presacral fat) | Not obvious | Normal |
5 | Low signal (equal to outer fibrosus) | Not obvious | Normal |
6 | Low signal | Not obvious | Reduce < 30% |
7 | Low signal | Not obvious | Reduce 30–60% |
8 | Low signal | Not obvious | Reduce > 60% |