“…Relatively similar T1 and T2 relaxation parameters among pathologic brain lesions, brain edema, and fibrotic tissue are obtained on T2WI, as compared with CE-T1WI (20). It is also known that the differences in signal intensities among the clusters are not sufficient to separate tumor components, such as solid, cystic, or hemorrhagic components, perilesional edema, and perilesional tumor infiltration, automatically on T2WI (10,22). According to the aforementioned reports, the T2WI-based semiautomatic segmentation method would be less reproducible in the groups with perilesional edema, with poorly demarcated inner margins of the necrotic portion, and with poorly demarcated outer tumor borders.…”