Orbital osteoma in Gardner's syndrome.

A 30-year-old woman developed proptosis secondary to a left ethmoidal compact osteoma. At age 29 years, a mandibular eburnated (ivory) osteoma was excised. At age 25 years, multiple adenomatous polyps of the colon were resected. Her father, age 61 years, had multiple intestinal polyps and bilateral mandibular osteoma. A 24-year-old sister had an osteoma of the forehead. Gardner's syndrome is an autosomal dominantly inherited disorder characterized by intestinal polyposis, various skin and soft tissue tumors, and osteomas of the bony skeleton. Orbital osteomas occur rarely.