Pure tone audiometry is a new method for evaluating congenital malformation of the middle and outer ear (CMMOE)

Abstract

Background: The preoperative evaluation of Congenital Malformation of the Middle and Outer Ear (CMMOE) is very important. Jahrsdoerfer score commonly used at present, based on CT scanning images of the temporal bone, is often unable to accurately evaluate deformity and hearing level.

Aims/Objectives: To investigate and promote a straightforward and easily accessible assessment method, pure tone audiometry, for the evaluation of CMMOE.

Material and Methods: A total of 223 cases (244 ears) CMMOE with hearing data were retrospectively analyzed. Among them, 180 cases (197 ears) underwent exploratory tympanoplasty with clear conditions: ossicle numbers in 136 cases (147 ears) and morphology in 128 cases (138 ears) and vestibular window development in 137 cases (146 ears), and CT scans of temporal bone in 113 cases (120 ears). 1). The correlation was analyzed between ossicle numbers, ossicle morphology, Jahrsdoerfer score groups and their corresponding Average Air-Conduction Threshold of pure tone (AACT) at 0.5–4 KHz. 2) The AACT difference is compared among the above groups respectively and between the developed and undeveloped groups of vestibular window at 0.5–4 KHz and each frequency of 0.125–8 KHz. Spearman method was used for correlation analysis (calculating coefficient r and p values). For the data followed a normal distribution, a one-way analysis of variance (ANOVA) and t-test were employed, otherwise, Kruskal Wallis multiple local rank coincidence test and Wilcoxon rank sum test were used. p <0 .05 was considered statistically significant.

Results: 1) The correlation coefficients between the groups of ossicle number scores, ossicle morphology scores, Jahrsdoerfer scores and their corresponding AACT are r = −0.187 (p <0 .05), r = −0.073 (p >0 .05) and r = −0.079 (p > 0.05), respectively. 2) Comparison of AACT difference based on ossicle number or morphological scores and Jahrsdoerfer scores with p > 0.05 among all groups, respectively. The AACT difference between the developed and undeveloped vestibular window groups is 5.5 (63.5/69.0) dB HL(p < .05) at 0.5–4KHz, out of 0.125–8 KHz frequency 1, 2, 4 KHz were 5.7 (65.0/70.7) dB HL, 8.4 (60.7/69.1) dB HL and 2 (61.5/63.5) dB HL, respectively, all p < 0.05, the other frequencies with all p > 0.05.

Conclusions and Significance: 1) Ossicle number was correlated with AACT, but not for ossicle morphology and Jahrsdoerfer scores. 2) There was no significant difference in AACT corresponding to ossicle number or morphology scores and Jahrsdoerfer scores groups, but the patients with undeveloped vestibular window had poorer hearing than those with developed ones. Therefore, the AACT can evaluate the development of ossicle and vestibular window, and more directly reflect the hearing level than Jahrsdoerfer score. Pure tone audiometry is simple, widely used, and easily accessible, which making it a new assessment method of CMMOE.

Chinese Abstract

背景: 先天性中外耳畸形(CMMOE)的术前评估非常重要。 目前常用的Jahrsdoerfer评分是根据颞骨的CT扫描图像, 往往无法准确评估畸形程度和听力水平。

目的: 调查并提倡一种直接且易于获得的评估方法, 用于评估 CMMOE。这种方法即纯音测听。

材料与方法: 对223例(244耳)CMMOE的听力数据进行回顾性分析。 其中180例(197耳)接受探查性鼓室成形术, 其病况明确: 136例(147耳)小骨数量及128例(138耳)形态及137 例(146 耳)前庭窗发生, 113 例(120 耳)颞骨 CT 扫描。 1)。 1)分析了小骨数量、小骨形态、Jahrsdoerfer 评分组和它们相应的在 0.5–4KHz时的纯音平均气导阈值 (AACT) 之间的相关性。 2) 分别比较上述各组之间以及前庭窗发育组和不发育组之间在0.5-4KHz和每个频率0.125-8KHz的 AACT 差异。 运用斯皮尔曼方法进行相关分析(计算系数r和p值)。 对于呈正态分布的数据, 运用了单向方差分析 (ANOVA) 和 t 检验; 否则, 运用了Kruskal Wallis多重局部秩符合检验和Wilcoxon秩和检验。 p<.05 被认为具有统计显著性。

结果: 1)听小骨数量评分组、听小骨形态评分组、Jahrsdoerfer 评分组与相应的 AACT 之间的相关系数分别为 r= −0.187 (p<.05)、r= −0.073 (p>.05) 和r= −0.079 (p>.05)。 2)基于小骨数量或形态学评分和 Jahrsdoerfer 评分的AACT差异的比较都为 p>.05。前庭窗发育和未发育组之间的差异在0.5–4KHz 处为 5.5 (63.5/69.0) dB HL (p<.05), 在 0.125–8KHz 频率 1、2、4KHz 处分别为 5.7 (65.0/70.7) dB HL、8.4 (60.7/69.1)dB HL 和 2 (61.5/63.5) dB HL , 所有都是 p<.05, 其他频率处p>.05。

结论及意义: 1)小骨数量与AACT相关, 但小骨形态和 Jahrsdoerfer 分数不是如此。 2)与听小骨数量或形态评分和 Jahrsdoerfer 评分组对应的AACT之间并无显著差异, 但前庭窗发育不良的患者与前庭窗发育良好的人相比听力较差。 因此, AACT 可以评估听小骨和前庭窗发育情况, 比 Jahrsdoerfer 评分更能直接反映听力水平。 纯音测听简单, 应用广泛且易于获取, 使其成为CMMOE的一种新的评估方法。

Keywords:

• Congenital malformation of the middle and outer ear (CMMOE)
• pure tone audiometry
• malformation evaluation
• ossicle development
• vestibular window development
• Jahrsdoerfer score

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by National Clinical Medical Center Special Project: YiHui Zou 202100003 and National Logistics Support Department Special Family Planning Project: YiHui Zou 22JSZ14.