In 2007, Watanabe et al. published grading of degenerative changes of the intervertebral disc by MRI. It is based on T2 weighted axial sections.
| Grade | T2 signal intensity (SI) of nucleus pulposus | T2 signal intensity (SI) of anulus fibrosus | Distinction of nucleus pulposus and anulus fibrosus |
|---|---|---|---|
| Grade I |
|
|
clear with regular borders |
| Grade II |
|
|
clear with irregular borders |
| Grade III |
|
|
unclear |
| Grade IV |
|
|
absent |
1. Watanabe A, Benneker LM, Boesch C, Watanabe T, Obata T, Anderson SE. Classification of intervertebral disk degeneration with axial T2 mapping. AJR Am J Roentgenol. 2007 Oct;189(4):936–42.