(634.18) Rare Presentation of Left-sided Thyroglossal Duct: A Case Report on Embryological Persistence

Poster Board Number: C93
Introduction: AAA has separate poster presentation times for odd and even posters.
Odd poster #s – 10:15 am – 11:15 am
Even poster #s – 11:15 am – 12:15 pm

Min Young Kim (Oakland University William Beaumont School of Medicine), Avianna Arapovic (Oakland University William Beaumont School of Medicine), Gorune Geloian (Oakland University William Beaumont School of Medicine), Sarah George (Oakland University William Beaumont School of Medicine), Corey Shafer (Oakland University William Beaumont School of Medicine), Malli Barremkala (Oakland University William Beaumont School of Medicine)

Thyroglossal duct (TGD) plays an important role in guiding the embryonic development and migration of the thyroid gland down the midline of the trachea. By the tenth week of gestation, TGD is completely obliterated with the thyroid gland in its proper position. In about 7% of the population, TGD persists and forms a thyroglossal duct cyst (TGDC) within the midline of the pretracheal neck region and often presents as the most common congenital midline neck mass. A rare finding of TGD from posterior base of the tongue to left-lateral pyramidal lobe, outside its normal midline pathway, was observed in a 92-year-old male during routine cadaver dissection of first year medical student’s curriculum at Oakland University William Beaumont School of Medicine. Upon further inspection of the thyroid, there was no evidence of hyperplasia or lesion in the thyroid or the thyroglossal duct itself. The thyroid and associated structures were studied by first year medical students during dissection in 25 formalin fixed cadavers (13 male, 12 female, average age of 76-years-old). Four of the 25 cadavers did not present with a thyroid due to previous thyroidectomy. The pyramidal lobe was observed in four of the 25 cadavers (19.05%), and a thyroglossal duct was observed in 3 of the 4 cadavers in the pyramidal lobe subgroup. Within this subgroup, only one cadaver displayed a left-sided thyroglossal duct. Currently, clinical literature suggest findings of TGDCs in four general regions of intralingual, suprahyoid, thyrohyoid, and suprasternal, but all within the midline pathway of TGD. This case finding reinforces the importance of CT scanning when treating patients with TGDC by surgical removal.