Lymphoproliferative Disorders of the Orbit and Ocular Adnexa

Lymphoma is the most common malignancy to affect the orbit and is frequently a diagnostic challenge for the radiologist. Any orbital and/or ocular adnexal structure may be involved with lymphoproliferative disease, and many conditions, such as idiopathic orbital inflammation and metastatic disease, may have a similar appearance on CT or MR imaging. Almost all ocular adnexal lymphomas are of the non-Hodgkin B-cell type. These vary in aggressiveness from the low-grade mucosa-associated lymphoid tissue type lymphoma to the highly malignant mantle-cell lymphoma, which is a disseminated disease with a poor prognosis. In this review article, we describe the CT and MR imaging findings in the various types of ocular adnexal lymphomas, its differential diagnosis, and prognostic implications. Histopathologic and genetic characteristics are briefly covered. Treatments of some conditions are briefly discussed.Learning Objectives: To help the reader recognize the ubiquitous imaging findings in ocular adnexal lymphoproliferative diseases and to formulate a meaningful differential diagnosis vis-a-vis conditions with similar imaging appearances.