Primary dural lymphoma masquerading as a meningioma

A 39-year-old woman noted progressive blurred vision in the right eye for 1 year. The right eye had visual acuity of 20/25, an afferent pupillary defect, pale optic nerve, and cecocentral scotoma. Magnetic resonance imaging findings were consistent with en plaque meningioma of the planum sphenoidale, which encircled the right optic nerve at the optic canal. The tumor was internally debulked to preserve the optic nerve. Histopathologic and molecular analysis revealed a low-grade B-cell lymphoma. Further evaluation showed no evidence of systemic disease. Primary dural lymphomas are a distinct entity that may mimic meningioma and cause vision loss.