Redefining anatomy in a case of midline subhyoid ectopic thyroid.

Abstract

Ectopic thyroid is an uncommon embryological aberration of the thyroid descent. Subhyoid median ectopic thyroid gland is a result of incomplete descent of the thyroid anlage and is characterized by a cosmetically unacceptable ovoid mass of thyroid tissue in the midline overlying the thyroid cartilage and thyrohyoid membrane. A normally placed thyroid gland is not detectable and in most cases all functioning thyroid tissue is located within the mass. Most of the ectopic thyroids are usually mistaken for a thyroglossal cyst and excised. Severe myxedema follows removal. Many cases have been reported in the literature, none of which was recognized prior to operation. All patients were operated upon for removal of a thyroglossal duct cyst. The diagnosis was missed at operation and in these cases severe myxedema was universal. The cause of the myxedema was not always immediately recognized. Therefore, many diagnostic tests including thyroid function test, ultrasound of the neck, and thyroid scanning had been recommended in the preoperative evaluation of a thyroglossal cyst. Here, we present a case of ectopic thyroid mass which was the only thyroid tissue present in the neck. So, division and repositioning of the thyroid mass thereby redefining the anatomy was done with good cosmetic results.