Orbital involvement in multiple myeloma. A new angiographic presentation.

A 49-year-old black female presented with proptosis, orbital pain, decreased visual acuity, and a left frontal bone mass. This lesion resembled a meningioma by computerized tomography and carotid angiography. Following craniotomy, a tissue diagnosis was made of plasmacytoma, with systemic myeloma found by bone marrow biopsy. This case was unusual in its radiographic appearance as plasmacytomas are usually avascular. This case illustrates that orbital plasmacytomas may radiographically mimic other orbital tumors such as meningiomas, melanomas, and orbital carcinomas, and that definitive diagnosis must often depend on histopathologic study.