Thyroid isthmus agenesis

The thyroid gland is the largest of all endocrine glands and is placed anteriorly in the lower neck in level with fifth cervical and first thoracic vertebrae. It is "H" shaped with two large lateral lobes, connected by a narrow isthmus in the midline. The gland bears very important clinical significance; both physiologically and pathologically and; a wide range of variations and anomalies of the gland have been reported. We report a case of complete agenesis of thyroid isthmus found during routine cadaveric dissection for the purpose of teaching learning of medial undergraduates at our department. This anomaly is quite uncommon and bears important clinical importance in wide fields of surgical and medical specialties. The embryological basis of the anomaly is high separation of a thyroglossal duct, which can give rise to two independent thyroid lobes with no isthmus