[Solitary eosinophilic granuloma of the external wall of the orbit]

Eosinophilic granuloma is a solitary form of histiocytosis X with a usually good prognosis. Sometimes spontaneous healing can even occur. The authors report a case of a 30-month-old boy who presented an eosinophilic granuloma of the lateral orbital wall. The correct diagnosis was obtained after computed tomographic scan followed by fine needle aspiration biopsy with histopathologic examination. The tumor increased rapidly, including a medial displacement of the globe and limitation of the eye movement. So chemotherapy (Vinblastine) with corticotherapy was performed. The clinical course was favorable, with no evidence of recurrence or systemic involvement. The originality of this case was the young age of the patient, the course and the efficacy of treatment. The authors emphasize the management of the disease.