from The Century Dictionary.
- Relating to the thyroid body or cartilage and the tongue: noting especially a duct existent in fetal life. See
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- adjective medicine Of or pertaining to the
from Wiktionary, Creative Commons Attribution/Share-Alike License
The connection of the diverticulum with the pharynx is termed the thyroglossal duct; its continuity is subsequently interrupted, and it undergoes degeneration, its upper end being represented by the foramen cecum of the tongue, and its lower by the pyramidal lobe of the thyroid gland.
The foramen cecum is the remains of the upper part of the thyroglossal duct or diverticulum from which the thyroid gland is developed; the pyramidal lobe of the thyroid gland indicates the position of the lower part of the duct.
As the fetus grows, the thyroid descends to the throat and attaches to the base of the tongue by the thyroglossal duct, which disappears as the fetus further develops.
A thyroglossal duct cyst is the most common congenital anomaly of the thyroid gland and midline masses in childhood (70% abnormality in childhood, 7% in adult).
Carcinomas arising from a thyroglossal duct cyst are rare (only 1% of thyroglossal duct cyst cases) and characterized by relatively non-aggressive behavior and rare lymphatic spread.