A<unk>  is a usually benign medical condition in which the<unk>  duct, a structure usually only found during embryonic development, fails to atrophy. The duct persists as a midline structure forming an open connection between the back of the tongue and the thyroid gland. This opening can lead to fluid accumulation and infection, which necessitate the removal of the duct.
Persistent thyroglossal duct
Tracheal agenesis
Salivary gland atresia
Patulous Eustachian tube
Salivary gland aplasia
Salivary gland hypoplasia
Laryngeal cleft
Omphalomesenteric duct cyst