Fig. 3.

Representative cases are shown. The left column shows a contrast-enhanced T1 image with the outline of a detected tumor. The right column image is a magnified image of the tumor and its surrounding area. The blue contour shows manual segmentation, while the red contour represents automated segmentation using the algorithm.A (case no. 30) is a case of left frontal base meningioma with a Dice index (DI) of 0.975, which is representative of highly accurate segmentation of the region bordering the superior sagittal sinus and falx cerebri.B (case no. 212) is a case of right convexity meningioma. Although the tumor was irregularly shaped, it was segmented with high accuracy (DI: 0.973).C (case no. 109) is a case of right parasagittal meningioma with a DI of 0.688 and poor segmentation. The tumor was small, and the contrast effect with the surrounding parenchyma was poor.