Thyroglossal cyst is the most common congenital malformation of the mid-neck region, related to the existence of the thyroglossal duct. During the formation of the thyroid gland, if the thyroglossal duct does not disappear and persists after birth, it will cause thyroglossal cyst.

Thyroglossal duct cyst is a congenital anomaly caused by an embryonic abnormality during thyroid gland formation. This anomaly affects approximately 7% of the population and can occur at any age, especially in children.