Influence of Brain Threshold on Gray-Level Normalization Parameters
| Method | α Variations (%) (mean ± SD) | β Variations (%) (mean ± SD) |
|---|---|---|
| Max | 0 | — |
| Mean | 1 ± 2 | — |
| Med | 1 ± 2 | — |
| Lin-1 | 1 ± 1 | — |
| DSC-1 | 1 ± 1 | — |
| Lin-2 | 6 ± 2 | 4 ± 2 |
| DSC-2 | 10 ± 3 | 6 ± 2 |
Brain threshold was varied in range (30%–50%) of maximum brain value. For each method, statistics were calculated within patient population from absolute value of α and β variations.