MRI findings of intracranial meningioma: significance of Gd-DTPA enhancement

To assess the usefulness of Gd-DTPA MRI in the evaluation of the characteristics of intracranial meningiomas and in the correlation with their histopathologic pattern. We retrospectively analyzed the Gd-DTPA MRI findings in 22 cases of histologically-proven intracranial meningiomas. The images were assessed for signal intensity, internal texture, peritumoral edema, and enhancement characteristic. Computed tomograms were obtained in 18 cases and compared with MRI findings. T1-weighted images were not particularly useful for discriminating pathologic subtype, but signal intensity on T2-weighted images were relatively well correlated with histopathologic findings. A heterogeneous texture produced by tumor vascularity, calcification, cystic foci, hemorrhagic necrosis, or psammoma body was relatively well shown on Gd-DTPA T1-weighted image compared with that on T1-or T2-weighted image. Gd-DTPA T1-weighted images revealed a dural tail sign in 19 cases(83%). Angioblastic type was slightly hypointense on T1-weighted image and markedly hyperintense on T2-weighted image. Psammomatous type and fibroblastic type were isotense on both T1-and T2-weighted image. Fibroblastic type was more densely enhanced than the other. The transitional, atypical, and papillary types showed tendency of heterogeneous enhancement. Gd-DTPA MRI was a useful imaging modality in evaluation of the characteristics of meningiomas and correlated well with the pathologic patterns