Fig. 6

Imaging of brain metastases by CT with contrast, MRI with contrast and IOUS. Arrows 1 refer to the fleshy tumor and arrows 2 refer to brain edema. Case a: Well-defined fleshy mass with heterogeneous enhancement and central necrosis in CT and MRI. Well-defined fleshy mass with hyper-echogenic periphery and hypo-echogenic center in IOUS. Case b: Ill-defined mass with heterogeneous enhancement in CT and well defined with homogenous enhancement in MRI. Well-defined fleshy mass mostly hypo-echogenic in IOUS. Case c: Ill-defined mass with heterogeneous enhancement in CT and well defined with heterogeneous enhancement in MRI. Well-defined fleshy mass with heterogeneous hyper-echogenicity in IOUS. The ultrasound criteria of high-grades tumors as noted in these cases are irregular contours, necrosis, brain edema, hypo-echogenicity, and heterogeneity