Agenesis of isthmus of thyroid gland in adult human cadavers: a case series

Abstract

The thyroid gland, a highly vascular endocrine gland, is composed of two lateral lobes connected by a narrow median isthmus thus giving an 'H' shaped appearance to the gland. A wide range of morphological variations and developmental anomalies of the thyroid gland have been reported in the literature. In our study, on the morphometric features of the thyroid gland it was found that, 6 out of 41 thyroid glands that were dissected, showed an absence of the isthmus. The respective lateral lobes were positioned independently on either side of the trachea. The incidence of agenesis of isthmus, along with the developmental and clinical significance are discussed herein under.

A Study on Visceral Abnormalities during Cadaveric Dissection

“…A high division of the thyroglossal duct can generate two independent thyroid lobes with the absence of isthmus. Incidence of agenesis of the thyroid isthmus has been reported to vary from 5% to 10% by Pastor et al ,8% to 10%, by Marshall,14.6% ,,by Dixit et al and33% by Ranade et al [6,7,8,9]. In our study we found it to be little low i.e.…”

“…Identification of completeness of fissure is important prior to lobectomy; because individuals with incomplete fissures are more prone to develop postoperative air leak [10,11].Prior awareness of abnormal position of hilum of kidney is very important for different renal surgeries..In planning biliary surgery or a portosystemic anastomosis, knowledge of abnormalities of lobes of liver is quite helpful for the surgeons. Agenesis of isthmus of thyroid gland can be associated with other types of dysorganogenesis, such as the absence of a lobe or the presence of ectopic thyroid tissue and hence in clinical practice when such a condition is diagnosed, it is necessary to perform a differential diagnosis against other pathologies such as autonomous thyroid nodule or thyroiditis [8].This study will definitely be helpful for the clinicians in planning and executing surgical and radiological interventions and also will be of great academic interest to all medical personnel.…”

Evidences of Thyroid Dysfunction in Case of Nodular Goiter (Ng)

“…Dixit et al [1] have described that thyroid gland is a highly vascular endocrine gland that is placed anteriorly in the neck, extending from the fifth cervical to the first thoracic vertebrae. Evered et al [2] have observed high serum TSH levels and normal T3 and T4 concentration in case of mild hypothyroidism while, Caldwell et al [3] have examined low serum TSH levels and high levels of T3 and T4 concentration in case of hyperthyroidism due to negative feedback mechanism.…”

Evaluation of Different Levels Thyroid Dysfunction in Patients having Diffuse Goiter from Rawalpindi and Islamabad

“…Thyroid gland is a highly vascular endocrine gland that is placed anteriorly in the neck, extending from the fifth cervical to the first thoracic vertebrae [1] have investigated that in case of mild hypothyroidism serum TSH also have been observed high and the values of T3 and T4 have remained in normal range.…”