Pogaku Mounika Bindu1, K. Srihari2, K. Venkatram Reddy3, R. S. Moorthy4, G. Rama Krishna Reddy5
Ectopic thyroid is a condition in which the thyroid tissue is present in locations other than the normal anterior neck region between the second and fourth tracheal cartilages. Its prevalence is 1 per 1,00,000-3,00,000 people. About 500 cases have been reported in the English literature mainly from Europe, Asia and America with a small number of reports coming from Africa. Ectopic thyroid tissue is a rare entity resulting from developmental defects in the migration of thyroid primordium from the foramen cecum at the base of the tongue to the infrahyoid portion of the neck between second and fourth tracheal cartilages. Ectopic thyroid tissue can occur anywhere along the course of the thyroglossal tract. Lingual thyroid is the most common type of ectopic thyroid accounting for 90% of cases. The most important differential diagnosis for ectopic thyroid is adenomas, metastatic thyroid tissue and hypertrophied lingual tonsil.