[Histiocytic disorders with orbital involvement].

The eosinophilic granuloma of bone is the most common type of histiocytic disorder involving the orbital area. Imaging data typically show bony defects with an intra-orbital soft-tissue extension. Surgical debulking is most often required. Rosai-Dorfman disease is commonly associated with uni- or bilateral orbital locations. The other histiocytic disorders are very rare, but some have a poor prognosis such as Erdheim-Chester disease.