What is thyroid Primordium?

The initial thyroid precursor, the thyroid primordium, starts as a simple midline thickening and develops to form the thyroid diverticulum. This structure is initially hollow, although it later solidifies and becomes bilobed.

What pouch does the thyroid come from?

The thyroid originates between the first and second pharyngeal pouches near the base of the tongue. In the third week of gestation, around day 20-24, endodermal cells of the primitive pharynx proliferate, creating the thyroid diverticulum.

Is thyroid an ectodermal?

Initial Thyroid Embryology The rudimentary lateral thyroid develops from neural crest cells, while the median thyroid, which forms the bulk of the gland, arises from the primitive pharynx. The thyroid gland forms as a proliferation of endodermal epithelial cells on the median surface of the developing pharyngeal floor.

What do the pharyngeal pouches become in humans?

The pharyngeal pouches develop into a series of structures that include the pharyngotympanic tube, middle ear cavity, palatine tonsil, thymus, the four parathyroid glands, and the ultimobranchial bodies of the thyroid gland.

What is a Sistrunk procedure?

The Sistrunk procedure consists of removing a thyroglossal duct cyst and surrounding tissues.

What arteries supply the thyroid gland?

The superior thyroid artery (STA) arising from the external carotid artery (ECA), and the inferior thyroid artery (ITA) branching from the thyrocervical trunk create the blood supply to the thyroid gland.

Do rats have thyroid glands?

The thyroid gland is the main target organ in rats, mice, and dogs.

Does the thyroid gland have a duct?

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. It is located exactly mid-line, between the anterior 2/3 and posterior 1/3 of the tongue.

What are the 5 pharyngeal arches?

The pharyngeal pouches separate the pharyngeal arches on the inner (endodermal) surface. There are five pairs of pouches, but only four give rise to structures in the adult….Pharyngeal Pouches.

What happens after Sistrunk procedure?

WHAT TO EXPECT AFTER SURGERY:

• Most children are fussy for the first few hours after surgery.
• Your child may get a red flushed look to his/her face and chest 1-2 hours after surgery.
• There will be an incision about 2-3 inches across the middle of the neck.
• Sometimes a soft drain is used.
• The wound may be slightly puffy.

Where is the tubercle of the thyroid gland?

The thyroid gland develops from 3 anlages: the larger median anlage and the paired smaller lateral anlages. The median anlage arises as an epithelial thickening in the ventral pharyngeal wall, in an area known as the tuberculum impar at the level of the second branchial arch.

How did the Zuckerkandl thyroid tubercle get its name?

The arrows indicate ZT and black dots indicate parathyroid glands. Although this tubercle is named after Austrian anatomist Emil Zuckerkandl, who described it in 1902 as processus posterior glandulae thyroideae, 6 it was first described by the German surgeon Otto Wilhelm Madelung in 1867 as the posterior horn of the thyroid.

Is the ZT a normal surgical landmark of the thyroid?

The ZT is a normal surgical landmark of the thyroid gland with important anatomic and radiologic variation.

How is the ultimobranchial body incorporated into the thyroid?

The ultimobranchial body is incorporated into the thyroid gland, disseminating its cells into the gland as the lateral and medial thyroid primordia fuse. The cause of the fusion is unknown, but the site at which these rudimentary structures fuse has been identified as the tubercle of Zuckerkandl.