Abstract
A case of severe obstructive sleep apnea syndrome caused by a dermoid cyst of the floor of the mouth is reported.
The patient was a 18-year-old woman with snoring and daytime sleepiness. On MRI, the tongue was pushed posteriorly by the presence of a large cystic lesion. On polysomnography, apnea and hypopnea were observed 526 and 212 times, respectively, during sleep, and the apnea hypopnea index was 82.0. The minimum SpO2 was 74%, and SpO2 decreased below 90% 207 times for a total of 4500 seconds during sleep. On contrast cephalography, the mean pharyngeal airway space was reduced. The diagnosis was severe obstructive sleep apnea syndrome resulting from a dermoid cyst. One week after removal of the cyst, apnea and hypopnea decreased to 67 and 140 times, respectively, and the apnea hypopnea index was 23.0. The minimum SpO2 became 87%, and the number and duration of SpO2 also decreased to 13 times and 170 seconds. No respiratory disturbance was observed 6 months postoperatively. The importance of respiration disturbance studies in patients with lesions causing constriction of the airways is stressed.
