Figure 2:
Effect of normalization on the region of interest (ROI) intensity histograms. Intensity histograms of the ROI segmentations from the scan (blue) and rescan (orange) of representative cases on both T2-weighted fluid-attenuated inversion recovery (T2W-FLAIR) and T1-weighted (T1W) postcontrast sequences of, A, a representative case and, C, a failure case. The first column shows ROI intensity histograms without preprocessing; the second column, after brain extraction and normalization via histogram matching; and the third column, after brain extraction and z score normalization. The overlap between the histograms is quantified by Jensen-Shannon divergence (JSD). B, D, Axial sections from the T2-weighted FLAIR and T1-weighted postcontrast scan and rescan after brain extraction of the corresponding cases, A, C, respectively.