Orbital hydatid cyst.

Hydatid cysts rarely appear in the orbital cavity without the involvement of the other organs. Most of them are situated in the superolateral and superomedial angles of the orbit. Inferiorly located cysts are very uncommon. The authors report a case of a primary hydatid cyst of the orbit with inferolateral localization. The cyst was removed surgically via a frontotemporoorbitozygomatic approach combination with puncture-aspiration-injection-reaspiration technique. This case was considered as a primary infection, because there was no previous history of hydatid disease and no findings of liver and lung cysts on radiological examination. Physicians should include orbital hydatid cyst in the differential diagnosis of unilateral proptosis. To avoid complications that might occur during surgery, the cyst can be easily removed using the combination technique detailed in this report.