Eye
Orbit & optic nerve
Inflammatory pseudotumor
Author: Nat Pernick, M.D.
Last author update: 1 February 2014
Last staff update: 18 May 2022
Copyright: 2004-2023, PathologyOutlines.com, Inc.
PubMed Search: Inflammatory pseudotumor orbit
Table of Contents
Definition / general | Case reports | Treatment | Gross description | Gross images | Microscopic (histologic) description | Whole mount images | Microscopic (histologic) images | Positive stains | Differential diagnosisCite this page: Pernick N. Inflammatory pseudotumor. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/eyeorbitinflammatorypseudo.html. Accessed September 28th, 2023.
Definition / general
- May not be a specific disease process, but due to various causes (paranasal sinus tumors, Rosai-Dorfman disease, inflammatory fibrosclerosis, dysthyroid ophthalmopathy, cholesterol or keratin granulomas, traumatic fat necrosis, prior hemorrhage or abscess)
- More common than infectious granulomas
- Usually ages 20 - 49 years with good health and sudden onset of exophthalmos with variable lid or conjunctival edema
Case reports
- 50 year old man with intraocular inflammatory myofibroblastic tumor with ALK overexpression (Arch Pathol Lab Med 2004;128:e5)
Treatment
- Steroids (alleviate signs and symptoms)
- Excision
Gross description
- Indurated orbital mass, often surrounding optic nerve and enveloping extraocular muscles
Gross images
AFIP images
Fibrotic mass surrounds the eye
Microscopic (histologic) description
- General:
- Edematous tissue with excessive production of ground substance, chronic inflammatory cells, vascular proliferation and hyperplastic connective tissue
- May have periphlebitis with tissue eosinophilia
- Inflammatory myofibroblastic tumor:
- Combinations of fibroblasts and myofibroblasts in background of plasma cells and other inflammatory cells
- Rosai-Dorfman related:
- Large histiocytes, some with lymphocytophagocytosis, lymphocytes and plasma cells, often with prominent fibrosis
Whole mount images
AFIP images
Dense fibrotic tissue
Microscopic (histologic) images
AFIP images
Inflammation and fibrosis
Chronic inflammatory cells
Positive stains
- Inflammatory myofibroblastic tumor: smooth muscle actin, variable ALK
Differential diagnosis
