Diagnosis: Congenital cyst of the newborn
The differential diagnosis for a congenital supraglottic mass includes lesions both intrinsic and extrinsic to the larynx. Vallecular masses, such as a thyroglossal duct cyst when it primarily involves the base of the tongue or a vallecular cyst as a result of obstruction of submucosal mucous glands in the region, are the more common supraglottic masses that originate outside of the larynx. Thyroglossal duct cysts characteristically contain thyroid follicles that can be identified by histologic examination. Laryngoceles and laryngeal cysts are congenital anomalies that are intrinsic to the larynx. Expansion of the saccule with air creates a laryngocele, and imaging reveals an air-filled dilatation that directly communicates with the ventricle, distinguishing this diagnosis from a laryngeal cyst.
Radiology Quiz Case 1: Diagnosis. Arch Otolaryngol Head Neck Surg. 2012;138(1):88-89. doi:10.1001/archoto.2011.224-b