Extramedullary hematopoiesis involving the bilateral lacrimal fossae

Abstract

Extramedullary hematopoiesis is a complication of a number of myeloproliferative disorders. MR imaging of the orbits was performed in a patient with bilateral orbital swelling with known myeloproliferative disorder and myelofibrosis. The study revealed symmetric, bilateral enhancing masses in the lacrimal fossae extending into the nasolacrimal ducts. Biopsy demonstrated sclerotic extramedullary hematopoietic tumor.

Fig 1.

Coronal T1 (A and B), coronal T2 fat-saturated (C), and axial T1 fat-saturated postgadolinium (D) images of the orbits. Homogeneous, well-defined T1-hypointense masses are seen in the lacrimal fossae bilaterally (A), extending inferiorly into the nasolacrimal ducts (B). These masses are largely hypointense on T2-weighted imaging with heterogeneous areas of hyperintensity (C). Diffuse enhancement is seen after gadolinium administration (D).

Fig 2.

Histologic features. These masses were characterized by a proliferation of pleomorphic, large cells, and fibrosis that infiltrated, surrounded, and replaced the normal tissue. Every specimen consisted of attenuated, sclerotic connective tissue within which large, atypical cells (megakaryocyte-like) with lobulated nuclei were found as well as scattered lymphocytes and granulocytes.