Thryoglossal Cyst Flashcards
What is a thyroglossal cyst
They are the cystic remnants of the thyroglossal duct, found along the path of descent of the thyroid.
What are the features of a thyroglossal cyst
75% are in the midline
Smooth and rounded
Moves on protrusion of the tongue and on swallowing
Why does a thyroglossal cyst move on protrusion of the tongue
Because the cyst is usually related to the base of the tongue by a patent or fibrous track which runs through the central portion of the hyoid bone
What is your differential diagnosis for a thyroglossal cyst
DDX includes other midline lumps:
- Thyroid nodules and masses
- Enlarged lymph nodes
- Other cysts - dermoid and epidermoid
- Subhyoid bursae
Who is likely to get a thyroglossal cyst
Rare
Equally common in males and females
40% present in the first decade - rarely present at birth
When does the thyroid descend
At the 4th week of development
What are the pathological features of a thyroglossal cyst
Lined by stratified squamous of ciliated pseudostratified columnar epithelium
May also contain thyroid or lymphoid tissue - can undergo malignant change
What malignancy is associated with thyroglossal cysts
Thryoid papillary type
