VI Международная студенческая научная конференция Студенческий научный форум - 2014

The thyroid gland is the first endocrine organ to evolve in the vertebrates. It has right and left lobes and connected by narrow median isthmus which lies over the second, third and fourth tracheal rings.

A conical pyramidal lobe often ascends towards the hyoid bone from isthmus or the adjacent part of either lobe. It measures about 1,25 cm transversely and vertically. Its size and site vary greatly. Isthmus is topographically related with some important anatomical structures. So this study was carried out to determine the incidence of presence and variation in anatomical position of isthmus of thyroid gland of people of different age groups to establish a normal standard.

The study was carried out on 60 cadavers of different age groups age ranging from 11 to 70 years in Forensic Medicine Department

The collected specimens were divided into age group A (upto 18 years), group B (18 to 45 years), group C (above45 years). All specimens were examined morphologically by fine dissection method.

In the present study isthmus was present in 41 (68.33%) cases. In those thyroids which were devoid of isthmus, lobes were found to be merged with each other in the midline but in one case two lobes were found completely separated from each other. It was evident that the posterior relations of isthmus were widely variable. In only 18% cases it was found at its usual position- against the 2^nd-4^th tracheal rings. In the present study more frequent location of isthmus was found at 1^st-3^rd and 2^nd- 4^th tracheal rings. In both cases their incidences were 18.3%.

The present study will help to increase the information pool on the anatomy of thyroid gland of Eastern Ukraine people. To establish a normal standard for Eastern Ukrainepeople, further studies with large samples from different zones of the country are suggested.