Thyroglossal duct cysts are collections of fluid in the neck and are usually located halfway up the neck in the midline, not along one side or the other. Often, these cysts seem to move in coordination with actions such as swallowing or sticking out the tongue.
Thyroglossal duct cysts are formed during a child’s development when the thyroid gland, located near the front of the neck, descends into the neck from an area near the base of the tongue. The resulting cyst connects to a small tract, or tube, which goes through the hyoid bone, higher in the neck, and eventually connects to the base of the tongue. This occurs before birth however, the thyroglossal duct cyst may not be recognised until later in life. The cyst may look like a small mass or a collection of fluid, and the affected area may become infected and red. However most thyroglossal duct cysts are painless and do not have any overlying skin changes.
Symptoms of thyroglossal duct cysts
Thyroglossal duct cysts often present as small, round or oval masses or lumps in the centre of the front part of the neck. They usually appear in preschool-aged children through adolescence. They affect males and females equally. The cysts can become larger over time, especially in children with an upper respiratory infection. Sometimes large cysts can cause difficulty swallowing or breathing.
Thyroglossal duct cysts can become infected, causing redness and tenderness in the area of the cyst. Rarely, the cysts create sinuses, or openings, to the skin through which the cysts drain on their own. In these cases, children will have a small opening in their skin near the cyst which drains fluid or mucus. This is uncommon, and typically follows an episode of infection.
Diagnosis of thyroglossal duct cysts
The diagnosis of a thyroglossal duct cyst is made by a health history and thorough physical exam. Your child will likely have an ultrasound to evaluate the mass.
Treatment of thyroglossal duct cysts
Thyroglossal duct cysts are benign and usually contain fluid that resembles mucus. Sometimes, an upper respiratory infection such as the common cold may cause the cyst to swell as it fills with additional fluid. This may be the first time that parents are able to see the cyst.
If the cyst becomes infected, surgeons will treat the infection first before removing the thyroglossal duct because the delicate connections between the cyst in the neck extending toward the base of the tongue are obscured by inflammation. Once the infection subsides, it will be necessary to remove the cyst.
Removal of a cyst before it becomes infected is preferable. Surgical treatment of thyroglossal duct cysts includes a small incision over the cyst, and if the tract connecting the cyst to the area near the base of the tongue is long, additional small incisions may be necessary.
When to call an ENT specialist
Please call your ENT doctor if your child has any of the following symptoms:
- Fever (a temperature of 101.5 degrees or higher)
- Any signs of infection, including redness, swelling or pain
- Any drainage from the incision
- Any pain that is not controlled with the prescribed pain medicine
- A mass or lump in the centre of the neck