新生儿与成人瞬态诱发耳声发射差异的频谱特性分析

Comparison of transient evoked otoacoustic emissions in newborns and adults with frequency specific approach

目的比较新生儿与成人瞬态诱发耳声发射（TEOAE）的差异，并分析其频谱特性。方法以短声刺激分别对120名通过听力筛查的新生儿（男58，女62）和32名平均纯音听阈（听力级）在20dB以内的成年人（男15，女17）行TEOAE检测，对于测试结果行频谱分析和半倍频程分析。结果①新生儿组TEOAE总强度（声压级，下同）为（15．18±4．39）dB，高于成人组的（9．51±4．12）dB，差异具有统计学意义（t=9．303，P〈0．05）。②新生儿的频带重复率、频带重复率非0比例、频带信噪比检出率及频带信噪比在第1频带（0．8kHz）最低，在3．2kHz最大；而成人在第5频带（4．0kHz）处最低，在1．5kHz最大。③新生儿与成人最大频带信噪比强度差为7．09dB，二者出现的频率位置相差约1．7kHz。④半倍频程分析显示新生儿TEOAE最大能量为（10．50±5．09）dB，在2828Hz处，而成人为（2．84±5．33）dB，在1414Hz处；二者最大反应在强度上相差7．66dB，出现的频率位置相差1414Hz。⑤成人1．5kHz区的TEOAE信号最强，之后其信噪比随频带增高而降低，而新生儿信噪比却呈现随频带增高而增强的特征；从第1频带到第5频带，新生儿与成人TEOAE强度的差值随频带增高也逐渐增大。结论成人TEOAE总强度低于新生儿。新生儿频带信噪比及半倍频程能量反应峰的分布频率及反应强度均高于成人。

Objective To investigate the difference of transient evoked otoacoustic emissions （TEOAE） between neonates and adults with the frequency-specific approach. Methods TEOAE were recorded from 112 newborns （62 females, 58 males） who passed hearing screening, and 32 adults （17 females, 15 males） tested with pure-tone threshold equal or less than 20 dBHL. Band reproducibility, signal-to-noise rate〈SNR） of frequency-band and haff-octave frequency analysis of TEOAE amplitude was recorded respectively. Results Significant differences were found in two groups, the higher entire TEOAE level found in newborn [ （15.18 ±4.39）dB SPL] was higher than that of adults group [ （9.51 ±4.12）dB SPL,P 〈0.05 ]. The lowest wave reproducibility and SNR were in first frequency band （0.8 kHz） for neonate, and then, in last frequency band （4.0 kHz） were for young adults. For newborns, the highest band reproducibility and SNR were presented at fourth frequency band （3.2 kHz）. However, for adults, the highest band reproducibility and SNR were presented at second frequency band （ 1.5 kHz ）. Frequency space of the SNR response peaks between neonates and adults was 1.7 kHz. The level difference was 7.09 dB SPL. Half octave frequency analysis shows a TEOAE response peaks in neonates was （ 10.50 ± 5.09） dB SPL at the 2828 Hz, and in adults, it was （2.84 ± 5.33） dB SPL at the 1414 Hz. Frequency space of the TEOAE response peaks between neonates and adults was 1414 Hz. Level differences of TEOAE response peaks was 7.66 dB SPL. TEOAE response peak in adult appear at 1.5 kHz, and then dropped down correlated to increase of frequency. From the first to the last testing frequency band, the difference of TEOAE level between neonate and adult was found to increase correlated to increase of frequency. Conclusions TEOAE response level in newborn is higher than that in adult group. Further, the decrease of TEOAE response level presented more sharpens with the frequency increasing in adult. The frequency of TEOAE response peak in neonate （3.2 kHz） is higher than adult （1.5 kHz）. The level of TEOAE response peak is also greater than adult.