Table 3.
Description of selected radiomic features in the Rad-score model.
| Feature Index | Filter | Feature Class | Feature |
|---|---|---|---|
| 1 | Original | First order | Kurtosis |
| 2 | Original | First order | Total Energy |
| 3 | Original | GLCM | Informational Measure of Correlation 2 |
| 4 | Original | GLCM | Maximal Correlation Coefficient |
| 5 | Wavelet (LH) | GLRLM | Long Run Low Gray Level Emphasis |
| 6 | Wavelet (LH) | GLSZM | Large Area Emphasis |
| 7 | Wavelet (LH) | GLSZM | Large Area Low Gray Level Emphasis |
| 8 | Wavelet (LH) | GLSZM | Zone Variance |
| 9 | Wavelet (HL) | GLCM | Maximal Correlation Coefficient |
| 10 | Wavelet (HL) | NGTDM | Busyness |
| 11 | Wavelet (HH) | GLSZM | Small Area Low Gray Level Emphasis |
| 12 | Wavelet (LL) | First order | Skewness |
| 13 | Wavelet (LL) | NGTDM | Strength |
Note—For wavelet filtration, “H” and “L” represent high pass filter and low pass filter on the x and y directions.
GLCM = Gray Level Co-occurrence Matrix, GLRLM = Gray Level Run Length Matrix, GLSZM = Gray Level Size Zone Matrix, NGTDM = Neighboring Gray Tone Difference Matrix.