[Ultrasonography and CT of thyroglossal duct cysts].

A retrospective analysis of pathologically proved 7 cases of thyroglossal duct cysts was performed in an attempt to determine the characteristics of these lesions using both ultrasonography (US) and computed tomography (CT). US showed cystic mass with variable internal echoes or debris in 6 of 7 cases and internal septation in two. CT showed hypodense mass in all 4 cases of which attenuation value were higher than that of water, and rim-enhancement of the wall in one case. CT and US also showed calcification of the wall in one patient. To our knowledge, calcification of the wall of thyroglossal duct cyst was not reported previously. These findings described above may be due to complicated inflammation, and may enable to differentiate the thyroglossal duct cyst from the other neck masses.