Nasopharyngeal Width and Its Association With Sleep-Disordered Breathing Symptoms in Children

OBJECTIVES: Although adenotonsillar hypertrophy is the main cause of sleep-disordered breathing in children, surrounding anatomic factors, such as the width of the nasopharynx, can affect upper airway patency. However, there have been no reports of the association of nasopharyngeal width with sleep-disordered breathing in children. This study was undertaken to measure nasopharyngeal width in children undergoing adenotonsillectomy for sleep-disordered breathing and to investigate the clinical implications of this factor. METHODS: This was a retrospective study with a follow-up period of 1 year, performed at a tertiary referral center. We reviewed the operative records of children who underwent adenotonsillectomy at our center for symptoms of sleep-disordered breathing, such as snoring, apnea, and mouth breathing. The nasopharyngeal width was measured immediately before adenotonsillectomy, which was performed under general anesthesia with a microscopy-assisted mirror view. Adenotonsillar hypertrophy was graded on a four-point scale, and symptoms of sleep-disordered breathing were evaluated by using the Korean version of the Obstructive Sleep Apnea-18 questionnaire before and after surgery. The relationships between the average nasopharyngeal width and patient age and sex, adenotonsillar hypertrophy, and the Korean version of the Obstructive Sleep Apnea-18 score were analyzed. RESULTS: The study included 549 children (343 boys) with a mean age of 6.0 years (range, 2 to 11 years). The average nasopharyngeal width was 11.9 mm (range, 7.0 to 18.0 mm) and increased with age (range, 11.2 to 13.3; β=0.264; P<0.001). At 1 year after surgery, children with a greater nasopharyngeal width at the time of surgery exhibited additional improvements in symptoms of obstruction relative to those at 1 month after surgery. CONCLUSION: The average nasopharyngeal width in children is approximately 11.9 mm and exhibits a slight increase with age. The width of the nasopharynx may be a factor associated with the degree of improvement in symptoms of sleep-disordered breathing after adenotonsillectomy.