An unusual case of orbital hydatid cyst: a surgical emergency.

A rare case of a 19-year-old man with an orbital hydatid cyst is presented. The lesion caused rapid deterioration of vision and was not responsive to the systemic use of mebendazole. It was treated successfully with emergency surgery. Early detection, surgical excision, and the systemic use of albendazole are suggested for the treatment of orbital hydatid cysts.