Orbital chordoid meningioma: a rare subtype of meningioma.

A 34-year-old woman presented with progressive proptosis of the right eye for 2 years. MRI revealed a well-demarcated mass in the right intraconal space, which was isointense on T(1)- and hyperintense on T(2)-weighted images with bright uniform enhancement. The mass was resected through a lateral orbitotomy. Histopathologic examination revealed cords and clusters of spindle and epithelioid cells embedded in a myxoid matrix, with vacuolated eosinophilic cytoplasm and round nuclei. The tumor cells were diffusely positive for epithelial membrane antigen and vimentin. These findings helped confirm the diagnosis of chordoid meningioma, a rare variant of meningioma with a greater risk of recurrence and aggressive growth. Many of the clinical manifestations and imaging findings were indistinguishable from those of cavernous hemangiomas, solitary fibrous tumors, neurofibromas, and other variants of meningiomas. Given the prognostic significance of chordoid meningioma, extra care and attention should be given during surgery, histopathologic assessment, and follow-up.