Department of Otolaryngology, Norfolk and Norwich University Hospital, Colney Lane, Norwich, United Kingdom.
Ear Hear. 2021 Sep/Oct;42(5):1109-1118. doi: 10.1097/AUD.0000000000001034.
The diagnosis of noise-induced hearing loss (NIHL) is reliant on the appraisal of audiometric data. A notch, dip or bulge, centered at the 4-kHz frequency is considered to be pathognomonic. However, guidelines applied to assist the diagnosis of NIHL often allow for a notch centered between the 3- and 6-kHz frequencies. The primary outcome of this review is to document the relationship between audiometric notching at particular frequencies and the populations in which they have been identified.
We included all population-based studies, cohort, cross-sectional, case-control, case-series, and case reports of adults and children, with exposure to noise and with a notch, dip or bulge. The review has been registered with Prospero (Registration: CRD42017079901) and prepared in line with the PRISMA guidelines.
We included 84 articles in the final systematic review. There were a total of 1,438,987 individuals, aged 7 to 80 years old. The studies were conducted in 26 different countries. Fourteen studies identified notching at 3 kHz, 63 studies identified notching at 4 kHz, and 47 studies identified notching at 6 kHz. The Newcastle-Ottawa risk assessment tool was performed on 82 of the studies emphasizing the high risk of bias in observational studies.
The overwhelming outcome of this systematic review demonstrates that the relationship between noise exposure and a 3- to 6-kHz audiometric notch is not straight-forward. A handful of articles have displayed a clear association between an individual's noise exposure and an audiometric notch. Unilateral notches, notches observed at 3 kHz and notches in the absence of continued high-intensity noise exposure must be scrutinized thoroughly. The ambiguous nature of NIHL directs its continued interest.
噪声性听力损失（NIHL）的诊断依赖于听力数据的评估。在 4 kHz 频率处出现的凹口、凹陷或凸起被认为是具有特征性的。然而，用于协助诊断 NIHL 的指南通常允许在 3 至 6 kHz 频率之间出现凹口。本综述的主要结果是记录特定频率处的听力图凹陷与已确定的人群之间的关系。
我们纳入了所有基于人群的研究、队列研究、横断面研究、病例对照研究、病例系列研究和成人及儿童噪声暴露病例报告，这些报告均有凹口、凹陷或凸起。该综述已在 Prospero 注册（注册号：CRD42017079901），并按照 PRISMA 指南进行准备。
我们最终的系统综述共纳入 84 篇文章。共有 1438987 人，年龄 7 至 80 岁。这些研究在 26 个不同的国家进行。14 项研究在 3 kHz 处发现凹陷，63 项研究在 4 kHz 处发现凹陷，47 项研究在 6 kHz 处发现凹陷。对 82 项研究进行了纽卡斯尔-渥太华风险评估工具评估，强调观察性研究存在高偏倚风险。
本系统综述的压倒性结果表明，噪声暴露与 3 至 6 kHz 听力图凹陷之间的关系并不简单。少数几篇文章显示出个体噪声暴露与听力图凹陷之间存在明确的关联。必须仔细审查单侧凹陷、在 3 kHz 处观察到的凹陷以及在没有持续高强度噪声暴露的情况下出现的凹陷。NIHL 的模糊性质使其持续受到关注。
