DOI: https://doi.org/10.36347/sjmcr.2024.v12i12.049

Pages: 2209-2212

The thyroid gland is made up of two conical-shaped lateral lobes connected by a middle, narrower isthmus. It is initially recognised in embryos with around 20 somites as a median thickening of endoderm located in the pharynx's floor, dorsal to the aortic sac and between the first and second pharyngeal pouches. The thyroid gland isthmus and lateral lobes are formed by the bifurcation of the thyroglossal duct tip and subsequent division of the tissue mass. Out of 23 cadavers dissected for routine undergraduate teaching, 1 cadaver with agenesis of thyroid isthmus was observed. The thyroid gland consisted of two lateral lobes, namely right and left, with no isthmus. The presence of a pyramidal lobe from the left lobe of the thyroid gland was noted, with the levator glandulae thyroidea connected to the pyramidal lobe of the thyroid gland. The presence of a facial sheath was observed in place of the isthmus of the thyroid gland, exposing the second and third tracheal rings underlying it. When making a diagnosis, it's critical to take into account the potential for ectopic thyroid tissue or the relationship between isthmus agenesis and thyroid lobe agenesis.