Congenital lateral cervical cysts of infancy.

The etiology of lateral cervical cysts in infancy is complex. The cysts are congenital in origin and are derived from the third or fourth branchial apparatus. The authors describe two cases of congenital lateral cervical cysts with an internal opening in the pyriform sinus and possible origin in the third branchial arch. The embryology, clinical presentation, and operative management of this condition is reviewed.