Dual ectopic thyroid.

Ectopic thyroid is an uncommon embryological aberration characterized by the presence of thyroid tissue in a site other than in its usual pre-tracheal region. It occurs along the path of descent of the developing thyroid primodium from the foramen cecum. It most commonly presents itself as a lingual thyroid and is the only thyroid in 70% of all cases. It is extremely rare for two ectopic foci of thyroid tissue to be present simultaneously. The authors report a recent case of dual ectopic thyroid present in the lingual and infrahyoid areas with no thyroid tissue in the pre-tracheal area in a 15-year-old girl. The patient had originally been scheduled for surgery under the impression of thyroglossal duct cyst; however, a pre-operative computed tomography scan of neck and thyroid scans revealed the presence of dual ectopic thyroid, thus preventing unnecessary surgery. Therefore, thyroid scan, along with either neck CT or neck ultrasonogram, should be performed routinely to avoid unnecessary surgery if the clinical picture is at all compatible with thyroid ectopia.