This is a mucus filled dilatation of the laryngeal saccule which may distort the aryepiglottic folds, false cord or laryngeal vestibule.
It is usually asymptomatic but may enlarge or become infected causing hoarse stridor and rapidly increasing airway obstruction.
Treatment is with excision of the cyst, or if this is not possible, a wide marsupialisation. Very rarely, tracheostomy may be required if the respiratory distress is severe.
Last reviewed 01/2018