History: 35-year-old woman with right true vocal cord paralysis after thyroid surgery, now with a left false vocal cord and neck ‘mass’.
Laryngocele refers to a congenital anomalous air sac communicating with the cavity of the larynx, which may bulge outward on the neck.
Findings: Axial CT images through the larynx demonstrate a predominantly air-filled mass within the left anterior cervical space and supraglottic larynx. The mass extends through the thyrohyoid membrane into the left periglottic space at the level of the false cord.
Diagnosis: Mixed larynocele
Discussion: Laryngoceles are abnormal dilatations of the laryngeal ventricle or its more distal saccule (often referred to as the appendix of the ventricle). Most laryngoceles are acquired and develop when the laryngeal ventricle is obstructed either functionally of structurally. Functional obstructions develop from conditions associated with increased intraglottic pressure such as excessive coughing, playing a wind instrument, or glass blowing. Ventricular obstruction can also be from neoplasms or inflammatory masses that obstruct the opening of the laryngeal ventricle. Symptoms depend on the location of the laryngocele. Internal or simple laryngoceles are confined to the paraglottic space of the supraglottic larynx (usually medial to the thyroid cartilage), whereas mixed or external laryngoceles begin as internal laryngoceles but enlarge and extend through the thyroid membrane into the anterior cervical or submandibular spaces of the neck. Laryngoceles are located superficial to the strap muscles, whereas thyroglossal duct cysts are usually embedded within them. Surgery is required for large or symptomatic laryngoceles. Adults who develop laryngoceles should be closely evaluated to make sure that an obstructing cancer is not in the region of the laryngeal ventricle. Interestingly, this anomaly is a common finding in gorillas.
Aunt Minnie’s Pearls
- Laryngoceles originate at the laryngeal ventricle.
- Be sure that a mass is not the etiologic agent of the obstruction that leads to laryngocele formation.