Klockhoff I, Lyttkens L
Scand Audiol. 1982;11(4):257-60. doi: 10.3109/01050398209087476.
Screening audiometry in children not infrequently reveals a 4 kHz dip. Evidence for noise trauma as the etiological background of this 4 kHz dip have been presented in the literature. Thirty children with hearing defects of this characteristic type and no history of noise exposure were studied. Their mean age was 14 years and the average observation time 4.2 years. Slight progression of hearing impairment (greater than 15 dB at two frequencies) was noted in 3 children (10%). A history of hearing defects in the family was found in 76%, as against 17% in a control group. Abnormal elevation of stapedius reflex thresholds was observed in 83% of the material. It is concluded that in children with a 4 kHz dip and no history of significant exposure to noise, genetic disposition is the predominant etiological element underlying the hearing defect. There was no indication of increased sensitivity to general noise exposure, but as always in sensorineural high frequency hearing loss avoidance of significant exposure to noise is to be recommended.
儿童听力筛查中时常会发现4kHz处听力下降。文献中已提出噪声性损伤作为这种4kHz听力下降病因背景的证据。对30名具有这种特征性听力缺陷且无噪声暴露史的儿童进行了研究。他们的平均年龄为14岁，平均观察时间为4.2年。3名儿童（10%）出现了听力障碍的轻微进展（两个频率处听力损失大于15dB）。76%的患儿有家族听力缺陷病史，而对照组这一比例为17%。在83%的研究对象中观察到镫骨肌反射阈值异常升高。得出的结论是，对于有4kHz听力下降且无显著噪声暴露史的儿童，遗传易感性是听力缺陷的主要病因。没有迹象表明对一般噪声暴露的敏感性增加，但对于感音神经性高频听力损失，一如既往地建议避免大量噪声暴露。
