Study subjects
Fifty children (aged 12.2 ± 3.0 years) were included in the study. Table 1 summarizes the demographic characteristics of the enrolled children. In total, 38 cases of NP (76%) were located in the middle meatus, 11 cases of NP (22%) were located in the maxillary sinus, and one NP (2%) was located in the sphenoid sinus.