Inflammatory Orbital Pseudotumor

Abstract

Later, particularly prior to the development of CT, the term was used for a variety of different orbital lesions now defined as distinct disease entities, such as foreign body reactions, inflammations within orbital capillary hemangiomas, dermoid cysts, etc. Essential qualifications were provided by Blodi and Gass (1968) and particularly by Jakobiec and Jones (1978), who defined inflammatory orbital pseudotumor as an “unspecific inflammation of orbital structures in the absence of systemic or local disease”. This definition must be further qualified since certain forms of inflammatory orbital pseudotumor, in particular ocular myositis and soft-tissue masses, may well be associated with proven systemic inflammatory disease, such as soft-tissue masses in panarteritis nodosa or Wegener’s granulomatosis, ocular myositis in rheumatoid arthritis or paraneoplastic syndromes.

“Birch-Hirschfeld (1905) is usually credited with defining the existence of a pseudotumor group of diseases. His classification included three types: (1) orbital tumor which subsides spontaneously, (2) exophthalmos which at operation had no distinct tumefaction causing it and which microscopically displays chronic inflammatory tissue, and (3) exophthalmos which at operation is caused by an abnormal orbital mass which has been created by a nonspecific inflammatory reaction.” (Jakobiec and Jones 1978)