[Hydatid orbital cyst: a unique intra-orbital locality. A case report]

Orbital hydatidosis is uncommon, accounting for 1 to 2% of all localizations. It is caused by Echinococcus granulosis, a dog parasite tapeworm. We report an intra-orbital hydatid cyst observed in a five-year-old boy, presenting the main features of this unusual localization. Hydatid cyst should be evoked in case of tumorous exophthalmia in young patients, especially in children having lived in endemic zones. The preoperative diagnosis is based on clinical findings and ultrasonographic, computed tomographic and magnetic resonance imaging findings. The fronto-orbital approach is most commonly used for treatment. Infectious and functional prognosis depends on early surgery.