Abstract

Background: The thyroid gland is a highly vascular endocrine gland. The gland consists of two lateral lobes and an isthmus connecting them across the midline, giving it an H-shaped appearance. Of all the endocrine glands, from widely noted to uncommon developmental anomalies are known to be associated with the thyroid glands. Literature has recorded different types of morphological disparities and developmental anomalies of the thyroid gland, which pose several clinical and surgical repercussions.
Objective: To discuss the morphometric features of thyroid gland and the incidence of agenesis of isthmus and its devel- opmental and clinical significances.
Materials and Methods: This study was conducted by dissection of the thyroid gland in 30 adult human cadavers all aged between 35 and 75 years, of which 25 were male and 5 female cadavers. Length and breadth of the right and left lobes and height of the isthmus were measured, and the presence of pyramidal lobe and levator thyroideae glandulae was noted. Result: The mean length of the right lobe measured 5.15 cm, and that of the left lobe measured 5.27cm. The mean breadth of the right lobe measured 3.5 cm, and that of the left lobe measured 3.7 cm. The mean length of the isthmus measured 1.55 cm. The pyramidal lobe and levator thyroideae glandulae were both present in four cadavers. There was no isthmus connecting the two lateral lobes in two cadavers. Conclusion: In order to ensure safe performance of surgical procedures in thyroid pathological conditions, agenesis of the isthmus of the thyroid gland should be accounted for.