<unk>  duct cysts most often present with a palpable asymptomatic midline neck mass usually below 65% of the time the level of the hyoid bone. The mass on the neck moves during swallowing or on protrusion of the tongue because of its attachment to the tongue via the tract of thyroid descent. Some patients will have neck or throat pain, or dysphagia. The persistent duct or sinus can promote oral secretions, which may cause cysts to become infected. Up to half of<unk> s are not diagnosed until adult life. The tract can lie dormant for years or even decades, until some kind of stimulus leads to cystic dilation. Infection can sometimes cause the transient appearance of a mass or enlargement of the cyst, at times with periodic recurrences. Spontaneous drainage may also occur. Differential diagnosis are ectopic thyroid, enlarged lymph nodes, dermoid cysts and goiter.<unk>  usually presents as a midline neck lump (in the region of the hyoid bone) that is usually painless, smooth and cystic, though if infected, pain can occur. There may be difficulty breathing, dysphagia (difficulty swallowing), or dyspepsia (discomfort in the upper abdomen), especially if the cyst becomes large. The most common location for a<unk>  is midline or slightly off midline, between the isthmus of the thyroid and the hyoid bone or just above the hyoid bone. A<unk>  can develop anywhere along a<unk>  duct, though cysts within the tongue or in the floor of the mouth are rare.A<unk>  will move upwards with protrusion of the tongue.Thyroglossal cysts are associated with an increased incidence of ectopic thyroid tissue. Occasionally, a lingual thyroid can be seen as a flattened strawberry-like lump at the base of the tongue. Complications Infection An infected<unk>  duct cyst can occur when it is left untreated for a certain amount of time or simply when a<unk>  duct cyst hasn't been suspected. The degree of infection can be examined as major rim enhancement has occurred, located inferior to the hyoid bone. Soft tissue swelling occurs, along with airway obstruction and trouble swallowing, due to the rapid enlargement of the cyst. With infections, there can be rare cases where an expression of fluid is projected into the pharynx causing other problems within the neck. File:Infected site.Post surgery infection on a<unk> , reaction from stitches. File:Post stitches infection.Post removal of stitches from surgery on a<unk>  infection<unk>  Fistula A<unk>  duct cyst may rupture unexpectedly, resulting in a draining sinus known as a<unk>  fistula.<unk>  fistula can develop when the removal of the cyst has not been fully completed. This is usually noticed when bleeding in the neck occurs, causing swelling and fluid ejection around the original wound of removal.<unk>  duct cyst carcinoma<unk>  with papillary excrescences (magnified at right), where microscopy showed papillary thyroid cancer. Rarely (in less than 1% of cases), cancer may be present in a<unk>  duct cyst. These tumors are generally papillary thyroid carcinomas, arising from the ectopic thyroid tissue within the cyst.
Thyroglossal cyst
Laryngeal cyst
Paradental cyst
Median mandibular cyst
Branchial cleft cyst
Colloid cyst
Vocal cord cyst
Gingival cyst