https://www.selleckchem.com/products/Dexamethasone.html Thirty-two patients (47%) were seen by a specialist and 19 had surgery. The majority of patients (55%) had headache as their presenting symptom. There were no statistically significant differences in the clinical presentation between those who received surgery and those who were observed clinically. CONCLUSIONS Silent sinus syndrome can present at any age. The majority of cases of maxillary sinus hypoplasia will have the orbital floor changes characteristic of SSS. Headaches are a common presenting symptom. Close follow up of pediatric patients is advised and early intervention may be favorable to prevent long term orbital changes and complications. OBJECTIVES Acute otitis media (AOM) is the most common infectious disease in infants and children. However, there have been few studies on the recent prevalence and trends of pediatric AOM in Korea. This study aimed to evaluate the prevalence and trends of pediatric AOM in Korea. METHODS The data for patients with AOM in 2012, 2015, and 2017 were extracted from the Health Insurance Review and Assessment Service's Big Database. The prevalence rate, recurrence rate, and data on gender, region, month, and medical facilities of AOM were evaluated. RESULTS The prevalence rate (per 1000 persons) decreased from 152.7 in 2012 to 137.4 in 2017. The recurrence rate declined from 34.0% in 2012 to 28.2% in 2015. In 2015, the recurrence rate of 0-2 years group decreased significantly. In 2017, the prevalence of AOM of 3-6 years group decreased the most. The prevalence is higher in urban areas and recurrence rate is higher in rural areas. But those are no significant difference. AOM is more common in male, mainly in winter and spring. CONCLUSIONS AND SIGNIFICANCE The prevalence and recurrence rate of pediatric AOM in Korea are gradually decreasing. The decrease of prevalence resulted from declination in AOM recurrence of 0-2 years group in 2015 and AOM occurrence of 3-6 years gro