The relationship between secretory otitis media (SOM) and hypertrophy of adenoid is generally believed to exist, but it has not clearly been demonstrated. On the other hand, we already showed that the suppression of the growth of pneumatization was closely related to the persistent state of otic inflammation like SOM in the early stages of growth. According to our pneumatization theory, 433 children who had SOM at the age 3 to 15 years were classified by the degree of pneumatization on x-ray films, and 276 children who had a large mastoid air cell system were treated only with conservative treatment. After this treatment, 229 cases of this group were in good condition but the other 47 cases were changed to the operative treatment because of the difficulty of treatment by conservative treatment. In these two groups, the degree of the hypertrophy of adenoid was compared on x-ray films and the rate of hypertrophied cases was significantly higher in the 47 cases than in the 229 cases (p<0.05). Children in both groups were suffuring from primary SOM because of their good pneumatization, and in these primary cases the hypertrophied adenoid was a large factor on controlling the disease.
