What is this?
- This is the thyroid gland.
- The thyroid gland is located below the thyroid cartilage with the thyroid isthmus below the cricoid cartilage, invested in pretracheal fascia.
- It is attached to the 2nd to 4th tracheal rings by Berry's ligament, hence why it moves up on swallowing.
- During development, the thyroid gland descends from the foramen caecum (2/3 along the length of the tongue from the tip) to pass forward and loop around beneath the hyoid bone.
- Incomplete descent, therefore, can lead to a lingual or pyramidal thyroid gland.
- An enlarged thyroid may expand downwards, resulting in a retrosternal thyroid.
- Incomplete closure of the pathway of descent may also result in a thyroglossal duct cyst, which can become infected.
- During removal, the middle 1/3 of the hyoid bone should also be excised to prevent recurrence.
- A thyroglossal cyst is a differential for a midline neck mass.
- It will rise up on protrusion of the tongue on examination.