Atypical C-T Features of Intracranial Meningiomas and Pathological Correlation

ABSTRACT

Most intracranial meningiomas present on the C-T as typical features with homogeneous, occasionally lobulated mass of density equal or greater than of surrounding brain tissue. After contrast injection, there is uniform and homogeneous enhancement in the density. Infrequently a significant number present as atypical features which are regional inhomogenecity of tumor mass on C-T and common source of error in the diagnosis of meningioma. The authors reviewed 25 consecutive meningiomas, all confirmed pathologically. 7 cases have been encountered as atypical features on the C-T. Among them, 2 cases of peritumoral low density were diagnosed as meningioma with C-T only. 5 cases(2 cases of peritumoral cyst, 2 cases of intratumoral cyst, 1 case of peritumoral bleeding) were misdiagnosed initially as malignant lesion based on C-T findings. Those C-T patterns have been found to correlate with certain histologic and morphologic alternation in tumor anatomy. Close correlation with pathological findings of tumor necrosis, cystic changes and hemorrhage was noted.