Intracranial meningiomas: correlations between MR imaging and histology.

The authors have examined the relationship between magnetic resonance imaging (MRI) and histopathological features in 35 surgically verified intracranial meningiomas. Tumor signals on T1-weighted images were rather similar regardless of the histologic subtype of the tumors. On T2-weighted images, hypointense meningiomas were mainly fibroblastic and hyperintense tumors were mainly syncytial and angioblastic, and partly transitional. Isointense tumors were mainly transitional and partly fibroblastic and syncytial. The authors conclude that the signal intensity of the MRI may be useful in the preoperative characterization of intracranial meningiomas. T1-weighted images may predict the presence of cysts and intratumoral blood vessels; whereas T2-weighted images can give information about histological subtype, vascularity and consistency. Meningiomas hyperintense to the cortex on T2 are usually soft, more vascular and more frequently of syncytial or angioblastic subtype; tumors hypointense or hypo-isointense on T2 tend to have a more hard consistency and are more often of fibroblastic or transitional subtype.