Langerhans cell histiocytosis located in the orbit

: Langerhan's cell Histiocytosis of the orbit. Langerhan's cell Histiocytosis is a rare condition that affects children and less frequently young adults. It is characterized by a proliferation of histiocytes derived from Langerhan's cells. Orbital involvement is described in 20% of cases where orbital eosinophilic granuloma located in the frontal bone is the most frequent. The malignant nature of this disease is not established. Its evolution is unpredictable and spontaneous regression after simple biopsy were described. The authors report four cases of Langerhan's cell Histiocytosis and will discuss on the clinical and radiological aspects as well as on the evolution of orbital histiocytoses X.