The thyroglossal duct is an embryological anatomical structure forming an open connection between the initial area of development of the thyroid gland and its final position.
The thyroid gland starts developing in the oropharynx in the fetus and descends to its final position taking a path through the tongue, hyoid bone and neck muscles. The connection between its original position and its final position is the thyroglossal duct. This duct normally atrophies and closes off before birth but can remain open in some people.
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