Thyroglossal Cysts

Question 1

Definition

Answer 1

An epithelium-lined cyst found along the course of descent of the thyroid gland

Question 2

Aetiology/Risk factors

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
o RARE familial variants

Question 3

Epidemiology

Answer 3

· Present in CHILDREN and ADOLESCENTS

· Mean age of presentation: 5 yrs

· 3 x more common than branchial cysts

Question 4

Presenting 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 on physical examination

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
o Lymph node
o Dermoid cyst
o 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
o Helps differentiate from other structures