[Nasopharyngeal changes in 8-13 years old healthy children in China: a longitudinal study].

Nasopharynx is an important compartment of the upper airway. It is closely associated with the characteristic craniofacial skeletal pattern related to sleep breathing. The present study aimed to investigate the growth pattern of the nasopharynx during rapid puberty growth period. Thirty non-snoring children (aged 8 to 11 years old) were selected by means of questionnaires and clinical examination. Periodic yearly follow up using MRI, lateral cephalogram, and polysomnograph (PSG) was done in these children. Fifty-one final mixed longitudinal samples were consisted of 23 children completed three consecutive follow-up, and 5 children completed two consecutive follow-up. The yearly changes of the nasopharynx and craniofacial structures were measured. ANOVA was used to evaluate the yearly growth of the nasopharynx. Correlated analysis was used to explore the potential influencing factors of craniofacial structures. The rapid growth period of the nasopharynx located in the age range of 8-10 years old, during which the transverse dimension of the nasopharynx developed rapidly, while the rapid development of the sagittal dimension of the nasopharynx was around 12-13 years old. The growth of the nasopharynx was continuous. The changes in the cross-sectional area of the nasopharynx (⊿CSA) was positively correlated with the changes in distance between mandible of glossopharyngeus (⊿M), distance of hyoid to cervical anterior surface (⊿H-CVP), and anterior pharyngeal distance of glossopharyngeus (⊿AD) (=0.363, 0.363, 0.323, respectively, all <0.05). The changes in the volume of the nasopharynx (⊿V) was positively correlated with the changes in upper facial height (⊿N-ANS), ⊿M, and ⊿AD (=0.336, 0.413, 0.478, respectively, all <0.05). The changes in the sagittal dimension of the nasopharynx (⊿S) was negatively correlated with angulation in supramental and anatomical horizontal line (⊿SNB) (=-0.322, =0.045). The changes in the transverse dimension of the nasopharynx (⊿T) was negatively correlated with the changes in adenoid (⊿A) (=-0.411, =0.009). The growth and development of the nasopharynx was early and continuous, which could be affected by the development of either maxilla or mandible.