Figure 4a.  Thyroglossal duct cyst in a 41-year-old man. (a, b) Axial contrast-enhanced CT scans show a cystic mass in the anterior midline of the neck just above (a) and at the level of (b) the hyoid bone. (c) Axial T1-weighted MR image at the thyrohyoid membrane level shows hyperintensity of the mass, a finding suggestive of proteinaceous content or hemorrhage.