Orbital hydatid cyst manifested as expanding exophthalmos following blunt orbital trauma

A 14-year-old boy suffered right blunt orbital trauma. X-ray revealed a compressed fracture of the right ethmoidal sinuses. Three months after the trauma, progressive, painless right proptosis developed. Ocular examination revealed a severe proptosis and pronounced down displacement of the right globe without signs of orbital inflammation. A well-demarcated, extraconal right orbital cystic mass was seen on computerized tomography scan. The cyst contents were aspirated and found to contain echinococcal scolices and "hydatid sand." Hypertonic saline was injected and the cyst was excised. Progressive proptosis after blunt orbital trauma in patients from endemic areas should be suspected of being an orbital hydatid cyst.