鼓膜チューブ挿入児の音響耳管検査成績 チューブ抜去時期の検討

Abstract

The present study investigated the eustachian tube function in children with otitis media with effusion (OME) and also evaluated the effectiveness of adenoidectomy in such patients. The subjects consisted of 32 children with OME, all of whom underwent tube insertion and adenoidectomy, resulting in an improved hearing level to a range of 0-10dB. Sonometric auditory function test was carried out on the patients whose tube was in place and the middle ear was well aerated. Normal transmission of sound was observed in 71.4% of these children. However, it was seen in only 2% of the children not surgically treated. Satisfactory tubal function was noted in patients whose ventilation tubes remained in place for a period of 250 days or longer. It is, therefor, suggested that the optimal timing of tube extraction should be approximately eight months post-operatively, at which time the eustachian tube appears to tart functioning well.Our second study measured intranasal pressure in children with OME when they performed Toynbee's manuever. Some children were treated with adenoidectomy with tube insertion and the others were not surgically treated, and the results were 5.66±2.92mm H2O and 3.93±1.79mm H2O, respectively. A significantly high intranasal pressure seen in patients with OME who had undergone adenoidectomy seems to account for the effective nasopharyngeal closure that had occurred as a result of improved movement of the soft palate including the levator veli palatine muscle. From these findings, it was concluded that adenoidectomy facilitates opening the tubal lumen by the tensor veli palatine muscle.