- 有料閲覧
- 文献概要
- 1ページ目
Ⅰ.緒言
騒音性難聴の発生及び進展には種々の要因が関与して来るが,その一つと考えられているものに既存の伝音難聴がある。
既存の伝音障害と音響外傷との関係についてはLarsen1),Goldner2)等,本邦では堀3),村上4),富永5),土肥6),草川7),藤野8),萩場9)等の報告がある。これ等を大別すると既存の伝音難聴は音響外傷に対して防禦的に働く,促進的に働く,あるいは影響なしとする3つの説に分れる。著者は既存の中耳伝音障害が音響外傷の発生に如何なる影響を与えているかを検討する目的で,騒音下の従業員中より一側に明らかな音響曝露以前より存在する中耳性難聴を有し,一側または両側に音響外傷によると推定される内耳性難聴が存在する例を選出して種々検討を加えてみた。
To what effect the noise trauma may have on the ear which is already affected with conduction hearing loss is studied on 8 selected cases. These were affected with hard of hearing from exposure to noise in whom there were preestablished loss of hearing in one ear from previous history of otitis media. In 4 cases the loss was negative when measured by the standard of airbone gap and bone conduction; in 3 cases the apparent loss appeared to be somewhat defensive in character; in 1 case alone the effect seemed to be porgressively active. Due to the fact that there are numerous causes entering into this condition which would make it premature to drow any conclusion from the results of these few cases. Further study of this subject is highly desirable.
Copyright © 1963, Igaku-Shoin Ltd. All rights reserved.