Table 1 The scale used for subjective image quality analysis
Grade | Visibility | Noise | Artifact | Overall |
|---|---|---|---|---|
1 | Not visible | Undiagnostic | Undiagnostic | Unacceptable |
2 | Mostly not visible or blurred | Strong noise but still diagnostic | Strong artifacts but still diagnostic | Average |
3 | Mostly visible but partially blurred | Acceptable noise | Acceptable artifacts | Fair |
4 | Subtle heterogeneity or blurring | Minimal noise | Minimal artifacts | Very good |
5 | Homogeneous internal intensity with sharp edges | No noise | No artifact | Excellent |