A Case of Subglottic Cyst Showing Discrepancy Findings Between Bronchoscopy and Computed Tomography

Abstract

The subglottic cyst is relatively rare. A boy born at 28 weeks of gestation had a birth weight of 1,202 g and required five days of endotracheal intubation during the neonatal period. At one year and two months of age, he developed a severe respiratory obstruction resulting in cardiopulmonary arrest, which required resuscitation. Flexible bronchoscopy under general anesthesia with a laryngeal mask revealed a small cyst on the right side of the subglottic space, but it was not considered to have been responsible for the critical airway obstruction. He showed frequent episodes of croup-like symptoms and was referred to us again at three years of age. Enhanced computed tomography showed a 5-mm cystic mass close to or inside the subglottic portion of the trachea, indicative of a subglottic cyst inside the trachea or a bronchogenic cyst compressing from the outside. We intended to excise the cyst via a cervical incision. As the cyst was not located outside the trachea, we performed meticulous unroofing of the subglottic cyst via laryngofissure with distal tracheotomy. During the follow-up period of one year, there was no recurrence of the cyst. However, another small cyst was found in the left subglottic area, but it did not increase in size during the subsequent six months of follow-up. One year and five months after tracheotomy, we cauterized the cyst using a diode laser and successfully decannulated the tracheostomy. We herein report our experience with the diagnosis and treatment of this patient with a subglottic cyst who had a somewhat unusual presentation of airway obstruction.