Thyroglossal cysts

Question 1

Define

Answer 1

DEFINITION: an epithelium-lined cyst found along the course of descent of the thyroid gland

Question 2

CAuses

Answer 2

The thyroglossal duct is an embryonic remnant of the path of descent of the thyroid gland from the mouth down to its normal position during development

The duct normally disappears in the 6th week, but if some tissue remains, it could develop into a cyst

Risk Factors

• RARE familial variants

Question 3

epidemiology

Answer 3

Presents in CHILDREN and ADOLESCENTS

Mean age of presentation: 5 yrs

3 x more common than branchial cysts

Question 4

Symptoms

Answer 4

A swelling/lump is noticed in the midline of the anterior neck

Usually ASYMPTOMATIC

May be tenderness or rapid enlargement due to infection

Question 5

Signs

Answer 5

Midline, smooth, rounded swelling

Typically found between the thyroid notch and the hyoid bone

Moves upwards on protrusion of the tongue

Moves upwards with swallowing

Can be transilluminated

Differential Diagnosis

• Lymph node
• Dermoid cyst
• Ectopic thyroid tissue

Question 6

Investigations

Answer 6

NONE may be necessary if the patient is euthyroid

If the cyst is suprahyoid, TFTs should be performed to exclude a lingual thyroid - because removal of the lingual thyroid will make the patient hypothyroid

Ultrasound/MRI

• Helps differentiate from other structures