Thyroglossal cyst arising from thyroglossal duct.

Aetiology:

Decent of thyroid anlage.

Pathology:

The cyst wall is lined by columnar epithelium sometimes squamous or cuboidal epithelium.

Sites:

Anywhere between base of tongue and thyroid isthmus.

1. Subhyoid (most common).
2. Suprahyoid.
3. Region of thyroid cartilage.
4. At level of cricoid cartilage.
5. Floor of mouth.
6. In substance of tongue.

Clinical features:

1)Age

a) Majority occurs in children younger than 10 years age, but it can occur at any age.

b) Patient may present with a painless lump in the midline of neck.

2)Inspection:

a) A swelling at the lower border of hyoid in midline or usually a little to the left.

b) Along long axis of neck.

c) Overlying skin is free and normal is color.

3)Palpation:

a) Fluctuant.

b) Transillumination: Rarely positive.

c) Swelling moves with deglutition and protrusion of tongue.

Treatment:
Sistrunk’s operation: :

Total excision of cyst or fistula with removal of central portion of the hyoid bone and core of tongue tissue around the tract in the suprahyoid tongue base to the foramen caecum. Simple excision of cyst without removal of its tract leads to recurrence.

Complications:

1)Recurrent infections when swelling increases in size and becomes painful.

2) Fistula.