Ipsilateral keratoconus associated with long-standing primary hydatid cyst of the orbit.

Hydatid cyst is a cyclozoonotic infection of the larvae form of a platyhelminthes Echinococcus granulosus. The majority of hydatid cysts appear in the liver (65%) and lungs (25%). Kidneys and brain are other less common sites for this disease. Only 1% to 2% cases are seen in the maxillofacial region. These commonly appear as cystic lesions located in the mandible, maxillary sinus, orbit, infratemporal fossa, pterygopalatine fossa, parapharyngeal space, tongue, and parotid and submandibular salivary gland. Hydatid cysts of the orbit are rare and account for 1% of all hydatid cysts. The article presents hydatid cyst of the orbit in a 10-year-old child. Clinical features, investigations, surgical approaches, and adjuvant medical management have been emphasized. We believe that the lateral orbital route allows excellent exposure and safe removal of an intraorbital hydatid cyst located posteriorly, superiorly, and laterally without damaging the surrounding important orbital structures. Upper blepharoplasty incision results in good cosmetic outcome.