Leontiasis ossea, also known as Lion Face Syndrome and Leontiasis is a rare medical condition which is described as an overgrowth of the facial and cranial bones. It’s not a disease, but rather a symptom of different diseases such as Paget’s disease, hyperparathyroidism, fibrous dysplasia, syphilitic osteoperiostitis and renal osteodystrophy.
The Lion Face Syndrome is based on one of the forms of fibrous osteitis. In the common form one or other maxilla is affected. Maxilla grows quickly affecting eyes, mouth and nose. When the disease is progressing the option nerve will be compressed by the bone overgrowth and it may cause a vision loss. The overgrowth can lead to breathing and eating challenges. Less common form affects all the cranial bones as well as those of the face. Suffering from this form person loses all senses one by one and it leads to death from cerebral pressure.
The only possible treatment is the exposing the bone with overgrowth, chipping away pieces or excising.
The term Leontiasis ossea first was used by Roman physician Galen to describe facial soft tissue changes in patients with leprosy and elephantiasis.