Congenital postauricular swelling in a child.

First branchial cleft cysts develop as a result of incomplete fusion of the cleft between the first and second branchial arches. In 1972, Work introduced a modified classification of these anomalies that recognized the existence of two types. Type I lesions, which are extremely rare, present as a cystic mass posterior to the pinna and concha. Type II lesions represent a duplication of both the membranous and cartilaginous portions of the external ear canal. They are associated with fistulas in the concha or in the external ear canal. Clinical and surgical management is often difficult because these anomalies have a variable relationship to the facial nerves. We describe a rare localization of a type I first branchial cleft cyst in a child and the clinical management with successive surgical treatment.