Acquired subglottic ductal cysts following prolonged intubation in preterm infants have been reported with increasing frequency during the past two decades. This paper reviews the subglottic ductal cysts diagnosed in 15 pediatric patients between 1989 and 1993--the largest such review. Eighty percent were observed in preterm low-birth weight infants following prolonged intubation, and all but 3 of the patients had major intubation trauma of the larynx--an association not previously reported. The cysts were usually multiple and arose in the posterolateral subglottis. Most were small and did not cause significant airway obstruction, but associated intubation changes were sufficiently severe to necessitate tracheotomy in 10 patients. The cysts observed in our study did not enlarge and in 4 patients were observed to spontaneously resolve or shrink in size--trends not previously reported. Subglottic ductal cysts noted in preterm infants after prolonged intubation most commonly occur in association with laryngeal intubation trauma and are likely a component of intubation trauma. Although these cysts may resolve without therapy, careful follow-up and treatment of potentially obstructing subglottic ductal cysts is recommended.