Computed tomography and the thyroglossal duct cyst.

Thyroglossal duct cysts (TDC) classically present as midline neck masses in close relation to the hyoid bone; yet--not uncommonly--their locations may be varied from the midline and from the hyoid. By means of the diagnostic modality of computed tomography (CT), high-resolution images of several cases of alternate presentations and locations of the TDC are examined. Included are examples of TDC in the suprahyoid, transhyoid, infrahyoid, and lateral positions. The potential value of CT in the diagnosis of the unusual cyst will be demonstrated and discussed.