Magnetic Resonance Imaging Findings Of Meningioma With Brain Edema And Pathological Correlation

Background and Objectives: Meningiomas are mostly benign, slow growing and extra-axial tumor that arise from the meningeal covering of the brain and physically separated by the leptomeninges from the brain. The arachnoid matter, the subarachnoid space, and the pia matter as well as the cerebral cortex, represent the anatomical barriers protecting the brain from edema associated with meningiomas. Instead of being benign and extra-axial origin, meningiomas are often accompanied by perifocal brain edema.Various hypothesis had been proposed by different authors in different literature but the exact pathogenesis is not still clear. The aim of this study is to determine what kind characteristics on magnetic resonance imaging (MRI) are indicative of the meningiomas that produce brain edema. We tried to study the relationship between location, size, shape, tumor margin, signal intensity of peritumoral rim, signal intensity of tumors on T₂WI, enhancement pattern and edema on MRI findings and then correlated with histology findings that which grades of meningiomas were accompanied by edema. The histology grading was done according to WHO classification of 2000. The term peritumoral rim means an intensity that shows hypointensity on T₁ weighted imaging and either hyperintensiy or hypointensity on T₂ weighted imaging surrounding peritumoral and brain interface.