MR imaging criteria subgroup analysis of symmetric (%ΔA < 33.7%) NPC and BH
| Volume | Signal Asymmetry | Deep Mucosal White Line | Adenoid | |
|---|---|---|---|---|
| Test positive for NPC | Volume ≥ 5.01 cm3 | Signal asymmetry present | Focal loss of the deep mucosal white line | Septa absent or distorted (excluding septa distorted by cysts) |
| n = 153 (NPC = 22, BH = 131) | n = 153 (NPC = 22, BH = 131) | n = 83 (NPC = 20, BH2 = 63) | n = 72 (NPC = 16, BH2 = 56) | |
| True-positive (No.) | 20 | 11 | 16 | 16 |
| False-positive (No.) | 42 | 15 | 8 | 8 |
| True-negative (No.) | 89 | 116 | 55 | 48 |
| False-negative (No.) | 2 | 11 | 4 | 0 |
| Sensitivity (%) | 90.1 | 50.0 | 80.0 | 100.0 |
| Specificity (%) | 67.9 | 88.5 | 87.3 | 85.7 |
| Positive predictive value (%) | 32.3 | 42.3 | 66.7 | 66.7 |
| Negative predictive value (%) | 97.8 | 91.3 | 93.2 | 100 |
| Accuracy (%) | 71.2 | 83.0 | 85.5 | 88.9 |