Thyroglossal duct cyst (TDC) arises from in the remnant of the thyroglossal duct anywhere in the line from the foramen cecum at the base of the tongue to the thyroid bed and is more common at the level of the hyoid bone. Infection is the most common complication of TDC. Malignancy is another rarer complication that occurs in 1-4% of cases.

Ultrasound is considered the first imaging modality for diagnosis of TDC in children.