Primary hydatid cyst of the infratemporal fossa.

Hydatid cyst disease is a rare parasitic disease caused by the larval stage of Echinococcus. This parasite in the larval stage can thrive in many parts of the body, most frequently in the liver. Head and neck involvement of the disease is rare. Herein, we present a case of primary hydatid cyst occurring in the infratemporal fossa, which is an extremely rare localization.