Cystic malformations of the neck in children.

The most common cystic malformations of the neck are the result of abnormal embryogenesis involving the thyroglossal duct (TGD), lymphatic primordia and the branchial apparatus. When the basic embryology of these structures is considered, a reasonable differential diagnosis-and in some cases a definitive diagnosis-can be achieved based on the location and the imaging characteristics of the cystic mass.