Method:Ear cannal volume (ECV), pure tone audiometry and distortion product otoacoustic emission(DPOAE) were carried out in 31 chidren(43 ears) with SOM before and 1 month after tube insertion,in the meantime Eustachian tube function was recorded.

• 方法:选择31例(43耳)临床诊断为SOM的患儿,分别在鼓膜置管术前及术后1个月,进行纯音听阈测试、畸变产物耳声发射(DPOAE)、鼓室导抗图(记录外耳道容积,ECV)测试;