The tongue develops after the thyroid primordium so the foramen cecum becomes buried at the base of the tongue. The<unk> <unk>  then continues through the neck and lies anterior to the laryngeal cartilage. The<unk>  then passes anteriorly to the developing hyoid bone; however, as the bone continues to grow it can continue to grow posteriorly, become anterior, or even grow to surround the<unk> . The<unk>  is found very close to the medial line of the neck. The<unk>  continues in front of the thyrohyoid membrane, sternothyroid muscle, and sternohyoid muscle, before terminating in the inferior segment of the neck at the thyroid. Failures of<unk>  removal surgeries have proven that the suprahyoid region of the<unk>  can have many microscopic branches that connect to the base of the tongue. They exhibit variability between different cases; however, it is believed they are associated with the pharyngeal mucosa and muscles of the tongue. Embryological origin During the third week of development, the thyroid gland begins to develop from the floor of the pharynx. This primordium begins as an evagination between the first and second pharyngeal grooves, relatively where the anterior two-thirds of the tongue ends. This area is known as the foramen cecum and marks the origin of the<unk> <unk> . As the developing thyroid begins to travel to its intended destination, it remains connected to the tongue via the<unk> <unk> . By the seventh week of fetal development, the thyroid reaches its final position in the neck after growing through the mesoderm and musculature of the tongue, mouth, and neck. During the eighth to tenth week, the cells of the<unk>  normally begin growing inwards and fill the previously hollow tube, beginning from the inferior end. This inferior end of the<unk>  will then become the pyramidal lobe of the thyroid gland. The dividing cellular cords of the tubular<unk>  become the isthmus and lateral lobes of the gland to complete the formation of the rest of the gland. Once the<unk> <unk>  involutes, the cells will begin to degenerate and disappear. However, in the case of a<unk> , the tube remains hollow and continues to connect the foramen cecum to the thyroid gland.
Persistent thyroglossal duct
Tracheal agenesis
Salivary gland atresia
Patulous Eustachian tube
Salivary gland aplasia
Salivary gland hypoplasia
Laryngeal cleft
Omphalomesenteric duct cyst