Fibrous dysplasia: findings in a pre-Columbian skull.

An ancient Peruvian specimen (600 to 800 years old) with fibrous dysplasia involving the left frontoethmoidal region is discussed. The skull is that of a woman aged 20 to 30 years exhibiting marked deformity of the left frontal bone, ethmoids, orbit, and nasal wall. Plane radiographs and tomographic views demonstrate a heavily calcified, expanding process in the frontal region and replacement of the ethmoids by less dense osseous tissue. This specimen represents the second reported instance of fibrous dysplasia occurring in the Americas, further documenting the antiquity of the disease on this continent. The lesion is probably monostotic and has characteristics similar to the process as it is known today.