Abstract:
Objective: This study was to investigate the main characteristics and related factors of wideband absorbance (WBA) in children with normal hearing and to obtain age-specific reference range of WBA. Methods: 384 children between 0-12 years old (615 ears) who visited the Beijing Children\'s Hospital, Capital Medical University from October 2019 to February 2021 were enrolled, including 230 males (376 ears) and 154 females (239 ears), with totally 306 left ears and 309 right ears. Wideband tympanometry (WBT) was performed and normative WBA data were analyzed by SPSS 24.0 statistical software. Repeated measures and multivariate analysis of variance were applied to the data from 16 points at 1/3-octave frequencies (226, 324, 408, 500, 667, 841, 1 000, 1 297, 1 682, 2 000, 2 670, 3 364, 4 000, 5 339, 6 727 and 8 000 Hz) to evaluate the effects of frequency, age, external auditory canal pressures, gender and ear on WBA. Results: According to the WBT frequency-absorbance curve, the subjects were divided into seven groups: 1-month old group, 2-month old group, 3-month old group, 4-5 month old group, 6-24 month old group,>2-6 year old group and>6-12 year old group. The WBA of normal-hearing children underwent a series of developmental changes with age at both ambient pressure and tympanometric peak pressures. WBA results for 1-month group and 2-month old group exhibited a multipeaked pattern, with the peaks occurring around 2 000 and 4 897 Hz, and a notch around 3 886 Hz. WBA results for 3-month group and 4-5 month old group exhibited a single broad-peaked pattern, with the peak occurring between 2 000-4 757 Hz. The WBA of 1-month old group to 4-5 month old group decreased gradually at low frequency (226-408 Hz) and 6 727 Hz, and increased at middle to high frequency (2 670-4 000 Hz). The WBA of 6-24 month old group were significantly lower than that of 2-month old group to 4-5 month old group at all frequencies except 3 364 and 4 000 Hz. WBA results for 6-24 month old group,>2-6 year old group and>6-12 year old group exhibited a single-peaked pattern, and the peak frequency of WBA moved to the lower frequency successively. From 6-24 month old group to>6-12 year old group, the WBA gradually increased at low to middle frequencies (667-2 670 Hz) and 8 000 Hz, and decreased at middle to high frequencies (3 364-5 339 Hz). Among the 16 frequencies of all age groups, the difference between WBA under ambient pressure and tympanometric peak pressure were -0.09-0.06, and 43.75%-81.25% frequency points had statistically significant difference, which was mainly manifested in that WBA under ambient pressure were lower than that under tympanometric peak pressure at 226-1 682 Hz. There was no significant ear effect on all of the age groups. Similarly, there was no significant gender effect except for 3-month old group and 4-5 month old group. Conclusions: The WBA of normal-hearing children measured at ambient pressure and tympanometric peak pressure varied across the frequencies with age from 1 month to 12 years old, and different frequencies followed different change patterns (increase vs. decrease) in WBA. There was also significant external auditory canal pressures effect on all of the age groups. The establishment of age-specific reference range of WBA for 0-12 years old normal-hearing children in this study would be useful for clinical practice of determining normative data regarding WBT.
目的: 分析0~12岁听力正常儿童宽频鼓室图能量吸收率(wideband absorbance,WBA)随年龄变化的特征及影响因素,获得与年龄相适应的参考值,为宽频鼓室图(wideband tympanometry,WBT)的临床应用提供参考。 方法: 对首都医科大学附属北京儿童医院2019年10月至2021年2月0~12岁听力正常儿童384例(615耳)进行环境压力和峰压下WBT测试,其中男230例(376耳)、女154例(239耳),左耳306例、右耳309例。应用SPSS 24.0软件对226~8 000 Hz区间1/3倍频程的16个频率点(226、324、408、500、667、841、1 000、1 297、1 682、2 000、2 670、3 364、4 000、5 339、6 727、8 000 Hz)的WBA值进行统计分析,以频率和测试压力(环境压力和峰压)为组内因素,年龄、性别、侧别为组间因素进行重复测量资料的方差分析和多元方差分析,探讨其对WBA的影响。 结果: 绘制各年龄段儿童的WBT频率-吸收率曲线,将走势相近的曲线进行整合,最终分为7个年龄组:1月龄组、2月龄组、3月龄组、4~5月龄组、6~24月龄组、>2~6岁组与>6~12岁组。频率、年龄、测试压力对WBA有显著影响:(1)1月龄组与2月龄组的频率-吸收率曲线呈双峰型,峰值分别在2 000和4 897 Hz附近,在3 886 Hz处有一个切迹,3月龄组与4~5月龄组为宽峰型,峰值在2 000~4 757 Hz之间;1月龄组至4~5月龄组的WBA在低频(226~408 Hz)及6 727 Hz逐渐降低,中高频(2 670~4 000 Hz)升高;6~24月龄组的WBA在除3 364和4 000 Hz外的频率范围较2月龄组至4~5月龄组显著降低;6~24月龄组、>2~6岁组与>6~12岁组的频率-吸收率曲线呈单峰型,其WBA峰值频率依次向较低频率移动,6~24月龄组至>6~12岁组的WBA在低中频(667~2 670 Hz)及8 000 Hz逐渐升高,中高频(3 364~5 339 Hz)逐渐降低。(2)各年龄组16个频率中,环境压力下和峰压下的WBA差值在-0.09~0.06之间,43.75%~81.25%的频率处差异具有统计学意义(P值均<0.05),主要表现在226~1 682 Hz环境压力下的WBA低于峰压下。除3月龄组和4~5月龄组外,性别对WBA的影响不显著;左右侧别对各年龄组WBA的影响均不显著。 结论: 不同频率处WBA随年龄增长遵循不同的变化模式,测试压力对WBA有显著影响,本研究建立了环境压力和峰压下0~12岁听力正常儿童WBA参考范围,可为WBT临床规范性数据的设定提供参考。.