Agenesis of the Thyroid Isthmus: A Case Report.
There are a large number of morphological variations of the thyroid gland. The thyroid glands original position is marked by the foramen caecum at the junction between the anterior two-thirds and posterior one-third of the tongue.
At the 4th week of intrauterine life, invagination of the endodermal cells of the ventral floor of
the primitive pharynx, gives rise to the thyroglossal duct. The duct descends to loop round the hyoid before its descent to the neck to give rise to two lateral buds which develop into the lateral lobes of the thyroid at the level of the second and third tracheal rings.
Variations in thyroid morphology are poorly understood and often associated with ectopic thyroids tissue and morphological anomalies in the gland. Mutation of thyroid transcription factor-2 has been identified as a factor leading to poor development of the gland.
Here, we discuss the case of a 25-year-old female who presented to the Ophthalmic Outpatient Department in a euthyroid state with a multinodular goitre, the isthmus agenesis
was an incidental finding during total thyroidectomy.
A 25-year-old Indian female patient presented with a single progressively enlarging swelling in the midline of the neck. The patient
reported to the OPD due to concern over the size of the neck
swelling. There was no associated difficulty in breathing or swallowing due to pressure exerted on the neck by the swelling. Patient
gave no history suggestive of change in weight, intolerance to heat
or cold, changes in the regular menstrual cycle or fatigue.
Otolaryngol Open J. 2020; 6(1): 5-7. doi: 10.17140/OTLOJ-6-160
