Uncommon Insidious Dumbbell-shaped Double Thyroglossal Duct Cyst.

As one of the most common congenital neck masses, thyroglossal duct cyst (TGDC) developed from the residual ductal epithelial cells in any remnants of thyroglossal duct. However, the reports of double TGDCs were rare. A 60-year-old male was referred to our department because of the presentation of an anterior neck mass. Only a hypodense oval mass inferior to hyoid bone was shown by computed tomography. During the Sistrunk operation, the dumbbell-shaped double TGDCs with the hyoid bone as the pivot were excised. No recurrence was observed. Before surgery, ultrasonography and computed tomography or magnetic resonance imaging should be conducted to verify the locations and sizes of TGDCs. During Sistrunk procedure, the rims of hyoid bone should be checked to avoid possible duct remnants.