Lipoma of the orbit

A 72-year-old woman presented with a history of painless, slowly progressive proptosis of the right eye which had developed during five years. The only functional defect was double vision in right gaze. A previous biopsy had only shown orbital fat. Magnetic resonance tomography showed a mass in the latero-superior orbit with high signal intensity similar to that of orbital fat. The tumor was completely resected by means of a lateral orbitotomy. Histology showed an encapsulated tumor composed of mature adult lipocytes with no mitotic cells or pleomorphism.Lipomas are extremely rare in the orbit. In the authors' case, the distinction between tumor and normal orbital fat was possible because the tumor was encapsulated. Thus total excision could be performed.