Extramedullary hematopoietic lesion of the orbit presenting as a ring enhancing lesion.

A 47-year-old healthy man presented with symptoms of double vision and drooping of the right upper eyelid. Examination disclosed signs of vertical diplopia and right upper-eyelid ptosis. An MRI delineated a well circumscribed, ring enhancing mass within the right orbit. The mass with peripheral enhancement located within the orbit, generated a broad differential diagnosis. After an excisional biopsy was performed, the mass was revealed to be fibrosis with extramedullary hematopoiesis. Current differential diagnoses of ring enhancing orbital lesions do not include extramedullary hematopoiesis, but we present a unique presentation of extramedullary hematopoiesis presenting as a ring enhancing orbital mass.