Figure 5. Imaging characteristics of each group after 2, 4, 8 w according to the X-ray and MRI. (A) Representative images of X-ray film. (B) Analysis of %DHI (DHI fold of control) based on X-ray (n=8). (C) Representative images of MRI. (D) Analysis of disc degeneration grades according to the Pfirrmann classification based on MRI (n=8). The values are expressed as mean ± SD. **P<0.01 vs control group; ^P<0.05 vs melatonin group; ^^P<0.01 vs melatonin group; ##P<0.01 vs puncture group; &&P<0.01 vs 2w puncture group.