Spheno-Orbital Meningioma With an Orbital Cystic Component

A 65-year-old male presented with a 5-year history of right-sided eyelid swelling and retrobulbar pressure sensation. Ophthalmic examination revealed visual acuity of 20/20 bilaterally, with no ocular motility defects or signs of compressive optic neuropathy. There was right upper eyelid fullness and 3 mm of proptosis (Panel A). MRI of the orbits demonstrated an expansile mass at the right greater wing of the sphenoid with intracranial extension to the middle cranial fossa and a large intraconal cystic mass in the lateral orbit causing mass effect on the lateral rectus, globe, and optic nerve (Panel B). No optic nerve signal abnormality was detected. An orbitotomy and biopsy were performed to obtain a tissue diagnosis of the cystic lesion and sphenoid bone (Panel C). Histopathological analysis showed a meningothelial neoplasm composed of sheets of spindle cells and inflammatory infiltrate with a prominent cystic component, revealing a WHO Grade 1 spheno-orbital meningioma (Panel D). Mitotic activity was 2 per 10 high-power microscopic fields, and the Ki67 proliferation marker was focally increased. The patient then underwent a gross total resection of the spheno-orbital meningioma and decompression of the optic nerve via a right pterional craniotomy. Spheno-orbital meningiomas are typically solid, en-plaque tumors with sheetlike infiltrative growth. Only 3.5% of all intracranial meningiomas have a cystic component, and cystic spheno-orbital meningiomas are even rarer, with only 1 case reported in the literature. Once the diagnosis is established, surgical management includes gross total resection when able.FIG.: