Fibrous dysplasia is a self-limiting, benign congenital fibrous tissue disease of unknown etiology that progresses slowly. It is a disease in which normal bone tissue is gradually replaced by proliferating fibrous tissue. The disease can be mono-bone or poly-bone (involving more than two bones). The lesion is considered a structural deformity characterized by the absorption of normal bone tissue and its replacement by fibrous tissue and underdeveloped reticular trabeculae. This disease is not uncommon clinically, accounting for about 25% of bone neoplasms. Less of them originate in the orbit, but the lesion often invades the periorbital bones, causing secondary changes such as a reduction in the volume of the orbital cavity, and clinical symptoms appear. The lesion grows slowly and usually stops growing after puberty. If skeletal system lesions are accompanied by skin pigmentation and/or endocrine disorders, it is called Albright syndrome.