English

Abstract

Among the human endocrine glands the H Shaped Brownish Red thyroid gland is well known for its disturbed organogenesis leading to a wide variety of morphological variations ranging from commonly occurring thyroglossal duct cyst and persistence of pyramidal lobe and rarely seen hypoplasia, ectopy, hemiagenesis & agenesis of isthmus. During the Routine Prosection hours an Elderly male cadaver showed agenesis of isthmus of thyroid gland exposing the Arch-anterior part of cricoid cartilage & the upper four tracheal rings the two lateral lobes of the gland were seen as two separate lobes without any nexus between them. The LGT was seen arising from the upper part of anterior border of the thyroid cartilage and got inserted into the substance of the right lobe along the lower 2/3 rd of its anterior border. Hence the LGT is aptly termed as Thyreoglandularis type. There was no supra isthmic arterial arcade formed by the anterior branches of the right and left superior thyroid arteries. There was no ectopic thyroid tissue present in the neck along the course of thyroglossal duct from the root of the tongue to the glands position The agenesis of the isthmus with right lateral LGT are very rare morphological variations and only scanty cases have been documented in the literature. In the present era of machine vision, various non-invasive radiological investigations such as USG, CT, MRI can bring into light, these otherwise clinically silent variations. Once suspected the subject can be directed for a thorough screening of differential diagnosis such as autonomous thyroid nodule, thyroiditis, neoplastic masses and infiltrative diseases like amyloidosis.