Reker U
Laryngol Rhinol Otol (Stuttg). 1975 Sep;54(9):741-7.
Two different otological noxes add up in their effect. In some cases, however, the first one may cause a reduction of the noxious effect of the second one. Opinions are divided as to whether the susceptibility to noise of an ear with chronic otitis media is increased or decreased. From 14,300 audiograms we selected those 131 cases with unilateral chronic otitis media and, at the same time, with a typical noise-induced recruitment-positive c5-dip on the other side. There were 86 cases with larger bone conduction hearing loss on the ear with chronic otitis media. In these cases, the bone conduction hearing loss, by all differential diagnostic criteria, could be judged to be caused by the chronic otitis media. On the other hand, in all those 45 cases which, on the side with chronic otitis media, had a bone conduction loss in form of a c5-dip, this was in each single case less pronounced than on the other ear. Regarding the susceptibility to noise, the reduction of sound intensity by the conductive deafness seems to be more important than noxious effects of the chronic otitis. Generally a substantial bone conduction hearing loss with chronic otitis media and noise exposure should be attributed to effects of the otitis.
两种不同的耳部致病因素叠加会产生综合效应。然而，在某些情况下，第一种因素可能会降低第二种因素的有害影响。对于慢性中耳炎患者的耳朵对噪音的易感性是增加还是降低，存在不同观点。我们从14300份听力图中筛选出131例单侧慢性中耳炎患者，同时另一侧有典型的噪声性重振阳性C5凹陷。其中86例慢性中耳炎侧骨导听力损失更大。根据所有鉴别诊断标准，这些病例中的骨导听力损失可判断为由慢性中耳炎引起。另一方面，在所有45例慢性中耳炎侧骨导损失呈C5凹陷形式的病例中，每一例的这种情况都比另一侧轻。关于对噪音的易感性，传导性耳聋导致的声音强度降低似乎比慢性中耳炎的有害影响更重要。一般来说，慢性中耳炎合并噪声暴露导致的明显骨导听力损失应归因于中耳炎的影响。
