Table 2. Model Performance and Comparison Between Model and Tmax and ADC Methods.
| Perfusion Model | Median (IQR) | ||||||
|---|---|---|---|---|---|---|---|
| AUC | DSC | PPV | Sensitivity | Specificity | Volume Error, mL | ||
| Lesion | Absolute Lesion | ||||||
| Minimal (n = 32) | 0.90 (0.85 to 0.94) | 0.58 (0.31 to 0.67) | 0.71 (0.39 to 0.85) | 0.54 (0.36 to 0.80) | 0.97 (0.95 to 0.99) | −3 (−84 to 18) | 39 (13 to 107) |
| Tmax >6 s plus ADC <620 × 10−6 mm2/s | 0.80 (0.74 to 0.85) | 0.55 (0.40 to 0.65) | 0.46 (0.33 to 0.81) | 0.57 (0.47 to 0.74) | 0.94 (0.90 to 0.96) | 9 (−72 to 55) | 59 (23 to 100) |
| P value | <.001 | .37 | .002 | .43 | .002 | .04 | .61 |
| Major (n = 67) | 0.93 (0.89 to 0.96) | 0.48 (0.29 to 0.65) | 0.41 (0.21 to 0.64) | 0.74 (0.50 to 0.80) | 0.97 (0.95 to 0.99) | 16 (−3 to 29) | 19 (10 to 33) |
| ADC <620 × 10−6 mm2/s | 0.71 (0.59 to 0.78) | 0.45 (0.15 to 0.54) | 0.44 (0.13 to 0.72) | 0.42 (0.19 to 0.59) | 0.99 (0.98 to 1) | −8 (−34 to 6) | 12 (7 to 34) |
| P value | <.001 | .002 | .02 | <.001 | <.001 | <.001 | .26 |
| Partial (n = 41) | 0.90 (0.86 to 0.96) | 0.53 (0.36 to 0.68) | 0.59 (0.38 to 0.82) | 0.61 (0.42 to 0.81) | 0.96 (0.92 to 0.98) | 9 (−31 to 37) | 36 (15 to 66) |
| Unknown (n = 42) | 0.92 (0.86 to 0.96) | 0.52 (0.31 to 0.67) | 0.54 (0.33 to 0.76) | 0.60 (0.39 to 0.86) | 0.96 (0.94 to 0.99) | 6 (−11 to 32) | 26 (10 to 38) |
Abbreviations: ADC, apparent diffusion coefficient; AUC, area under the curve; DSC, Dice score coefficient; IQR, interquartile range; PPV, positive predictive value; Tmax, time to maximum of the residue function.