正常新生儿226Hz及1000Hz探测音鼓室导抗测试

探讨通过瞬态诱发耳声发射(TEOAE)筛查的正常新生儿低频（226Hz）及高频（1000Hz）探测音鼓室导抗图的特点、获得峰声导纳值等指标的正常值范围,为临床新生儿及婴幼儿中耳功能评估和诊断提供依据。方法采用中耳分析仪（GSI-33型）对足月顺产,并通过TEOAE筛查的正常新生儿分别进行低、高频探测音下的鼓室导抗测试,分析鼓室导抗图形态特征并对峰声导纳值等重要数据进行统计。结果在100例首次双耳通过TEOAE筛查的新生儿鼓室导抗测试中,低频鼓室导抗图以双峰型为主（占96%）,高频鼓室导抗图以单峰型为主（占90%）;低频探测音鼓室导抗图为双峰型而其高频探测音鼓室导抗图为单峰型的有174耳（占总耳数87%）;低频及高频探测音鼓室导抗图均为单峰型的仅有6耳（占总耳数3%）。结论正常新生儿低频探测音鼓室导抗图以双峰型为主,高频探测音鼓室导抗图以单峰型为主,应将两者结合来对新生儿及婴幼儿中耳功能进行评估;所获得相应的峰声导纳值、峰声导纳值处外耳道压力、外耳道容积等指标的正常值可以用于初步评估新生儿中耳功能状态。     

听力正常新生儿1000Hz声导抗分析

目的 分析通过耳声发射(OAE)听力筛查正常新生儿1000 Hz声导抗测试的特点,为新生儿听力筛查及新生儿中耳功能的评估提供参考依据.方法 采用GSI-70型自动耳声发射听力筛查仪对新生儿进行听力筛查,将双耳通过OAE听力筛查的正常新生儿按照纳入标准选为研究对象,共650例(1300耳),然后采用GSI TympStar VersionⅡ中耳分析仪对该研究对象进行中耳功能测试,收集探测音为1000 Hz的鼓室导抗图及其相关指标,对图形进行分型并计算各指标的95％医学参考值范围.结果 将纳入的1300耳的鼓室导抗图分类,其中1Y1B1G型732耳(占56.3％)、1Y3B1G型145耳(占11.2％)、0Y0B0G型269耳(占20.7％)、其他154耳(占11.8％).其中声导纳图Y中单峰型有967耳,计算单峰型声导纳图Y各指标的95％医学参考值范围,其中鼓室图峰压(tympanometric peak pressure,Tpp)为- 55.0～180.0 daPa、峰补偿静态声导纳值(peak compensated static acoustic admittance,Peak Ytm)为0.03 ～1.18 mmHo、鼓室图宽度(tympanometric width,TW)为70.0～230.0 daPa.结论 通过OAE听力筛查的正常新生儿1000 Hz探测音的声导纳图Y以单峰型为主.1000 Hz探测音的单峰型声导纳图Y的Tpp、Peak Ytm、TW的95％医学参考值范围可作为新生儿听力筛查及新生儿中耳功能评估时的参考依据.     

Evaluation of tinnitus patients with normal hearing sensitivity using TEOAEs and TEN test

Objectives

This study was designed to investigate the possibility of underlying cochlear damage whether outer hair cells (OHCs) or inner hair cells (IHCs) in tinnitus suffering patients with normal hearing sensitivity, using transient evoked otoacoustic emission (TEOAEs) and threshold equalizing noise (TEN) test, if any.

Methods

Twenty patients suffering from unilateral tinnitus with normal hearing sensitivity participated in this study. Their other ear acted as control ears. They were subjected to full history taking, otoscopy, basic audiologic evaluation, TEOAEs and TEN test.

Results

TEOAEs were abnormal in 85% of the tinnitus ears compared to 20% in control ears; this difference was statistically significant. The abnormal TEOAEs frequency bands in the tinnitus ears were statistically significant above 2000 Hz when compared to the control ears and were more common for the 4000 and 5000 Hz. This suggests that OHCs dysfunction may be important in the generation of tinnitus. TEN test demonstrated dead regions in the cochlea in 15% of the tinnitus ears only. This might be attributed to increased resistance of IHCs to damage compared to OHCs vulnerability. The affected frequency location was at 500 Hz in 5%, 3000 and 4000 Hz in 10% of tinnitus ears.

Conclusion

This work has shown a higher prevalence of OAE abnormalities in tinnitus patients with normal hearing in contrast to TEN test denoting the more vulnerability of OHCs to damage.     

High- and Low-Frequency Probe Tone Tympanometry in Chinese Infants

Objective To assess the utility of low- and high-frequency tympanometry in the diagnosis of middle ear dysfunction in Chinese infants. Methods Tympanograms were obtained with 226 Hz, 678 Hz and 1000 Hz probe tones from infants aged 5-25 weeks with normal auditory brainstem responses (ABRs)(15 infants,30 ears) and withprolonged wave Ⅰ latencies(17 infants, 20 ears), suggesting middle ear dysfunction, using a GSI Tympstar middle ear analyzer Version Ⅱ. Results The single-peaked tympanogram was the most characteristic type in both groups and seen in 25 ears (83.3%) in the normal ABR group and in 18 ears (90%) in the delayed wave Ⅰ group, respectively. The peak pressure, peak compensated static acoustic admittance and gradient of 226 Hz tympanometry were of no significant differences between the two groups. The 678 Hz tympanograms of admittance, susceptance and conductance demonstrated non-peak, single-, double- and tri-peaked patterns in both groups. The agreement between ABRs and 678 Hz tympanograms of admittance,susceptance and conductance were 70.0%, 58.0% and 64.0%(kappa=0.324, 0.234 and 0.118) respectively. For 1000 Hz probe tone, admittance,susceptance and conductance tympanograms showed single peaked patterns in 28 (93.3%), 25 (83.3%) and 26 (86.7%) of the 30 normal ears. Admittance, susceptance and conductance tympanograms using the 1000 Hz probe tone were flat in 15 (75%), 17(85%) and 13 (65%) of the ears in infants with prolonged wave Ⅰ latencies. For 1000 Hz admittance, susceptance and conductance Tympanograms, the agreement between tympanometry and ABR results were 90.0%, 92.0% and 86.0% with kappa at 0.783, 0.831 and 0.690, respectively. Conclusion 1000 Hz probe tone tympanometry is a promising middle ear function test for infants of 1-6 months age, while 226 Hz and 678 Hz probe tones are less efficient in detecting middle ear dysfunction in infants.     

中耳共振频率对鼓室积液的诊断价值

目的:探讨226 Hz静态鼓室图与中耳共振频率诊断鼓室积液的价值,观察两者结合可否提高诊断效能.方法:前瞻性研究对比观察分泌性中耳炎组和对照组,以耳镜检查、纯音测听及GSI-33型中耳分析仪测试结果为标准,将对照组共振频率90%的可信区间(5%～95%)设为正常范围,对分泌性中耳炎组的共振频率进行正常或不正常归类,并对其鼓室图形为B、C型或异型者进行鼓膜穿刺抽液,以抽出液体者为阳性.结果:中耳共振频率在900～1100 Hz之间为正常,分泌性中耳炎组的共振频率明显低于对照组(P＜0.01).B型曲线的抽液阳性率为83%,明显高于C型和异型曲线抽液阳性率(P＜0.05).共振频率正常者,其抽液阳性率为0.≤500 Hz者的鼓室积液阳性率明显高于＞500 Hz者(P＜0.01).结论:通过测试中耳共振频率对判断鼓室是否积液,尤其是对鼓室图形为C型或异型者有重要临床意义.     

Evaluation of cochlear involvement by distortion product otoacoustic emission in Behçet's disease

Objective

The aim of this study was to investigate cochlear involvement in patients with Behçet's disease.

Materials and methods

Twenty-six Behçet's disease patients (52 ears) and 24 sex and age-matched healthy control subjects (48 ears) were included in the study. Pure-tone audiometry at frequencies 250, 500, 1000, 2000, 4000, 6000 Hz, immittance measures including tympanometry and acoustic reflex testing and DPOAE (distortion product otoacoustic emission) testing were performed in the patients and controls.

Results

A sensorineural hearing loss was found in eight patients (30.7%) as it was bilateral in five and unilateral in three patients. Although no typical audiometric configuration was found, one patient had a flat type audiogram, and the others had a high frequency hearing loss. The DPOAE responses of the patients and controls were significantly different in all frequencies (p < 0.05).

Conclusion

These results indicate that cochlea is affected by damage of outer hair cells in Behçet's disease.     

High-frequency (1000 Hz) tympanometry in normal neonates

The characteristics of high frequency (1000 Hz) acoustic admittance results obtained from normal neonates were described in this study. Participants were 170 healthy neonates (96 boys and 74 girls) aged between 1 and 6 days (mean = 3.26 days, SD = 0.92). Transient evoked otoacoustic emissions (TEOAEs), and 226 Hz and 1000 Hz probe tone tympanograms were obtained from the participants using a Madsen Capella OAE/middle ear analyser. The results showed that of the 170 neonates, 34 were not successfully tested in both ears, 14 failed the TEOAE screen in one or both ears, and 122 (70 boys, 52 girls) passed the TEOAE screen in both ears and also maintained an acceptable probe seal during tympanometry. The 1000 Hz tympanometric data for the 122 neonates (244 ears) showed a single-peaked tympanogram in 225 ears (92.2%), a flat-sloping tympanogram in 14 ears (5.7%), a double-peaked tympanogram in 3 ears (1.2%) and other unusual shapes in 2 ears (0.8%). There was a significant ear effect, with right ears showing significantly higher mean peak compensated static admittance and tympanometric width, but lower mean acoustic admittance at +200 daPa and gradient than left ears. No significant gender effects or its interaction with ear were found. The normative tympanometric data derived from this cohort may serve as a guide for detecting middle ear dysfunction in neonates.     

Is sensorineural hearing loss with chronic otitis media due to infection or aging in older patients?

Objective

To clarify true incidence of sensorineural hearing loss in ears with chronic otitis media (COM).

Methods

Bone conduction (BC) hearing thresholds of 180 preoperative patients (207 ears) with COM and 226 normal individuals (289 ears) were measured by audiometry, and the percentage of ears with BC thresholds being higher than normal range was evaluated in the COM group. In the COM group, the size of the perforation on the eardrum (n = 196) and the cross-sectional area of the mastoid air cells based on the axial CT image (n = 103) were also measured and correlated with the results of BC threshold.

Results

The percentage of ears with BC thresholds being higher than normal range calculated from comparison to the control group tended to increase with age, ranging from 4.5% in the 20s to 34.1% in the 60s with an average of 26.6%. The increase in the BC thresholds did not correlate with the size of eardrum perforation, but correlated well with the size of the mastoid air cells.

Conclusion

These results may suggest that all measures for early cure, including surgery, should be considered as early as possible for patients with COM.     

A comparison of tympanometry with 226 Hz and 1000 Hz probe tones in children with Down syndrome

Background

For children with Down syndrome, the incidence of hearing loss may be as high as 78% [1], therefore the American Academy of Pediatrics recommends regular screening for the presence of hearing abnormalities. Tympanometry is used as an indication of middle ear pathology. In our experience, Down's patients’ tympanograms do not always correlate with otoscopic findings. Down's patients have joint laxity, small ear canals, anterior tympanic membrane orientation and softer tissue composition, all factors thought to affect tympanogram results in infants. Because the use of the 1000 Hz tympanometry is widely recognized as standard procedure in the evaluation of infants aged 0–6 months, we propose it may have greater reliability in testing patients with Down syndrome.

Objective

Compare the results of visual inspection of the tympanic membrane by a Pediatric Otolaryngologist to the results of tympanometry at traditional probe tone (226 Hz) and at the infant probe tone (1000 Hz).

Methods

Institutional Review Board – approved prospective study of 26 subject-ears in patients with Down syndrome aged 6 months–18 years but recent stable middle ear/Eustachian tube function using physical examination and tympanometric probe tones at 226 Hz and 1000 Hz.Subject-ears were examined with record of “clear of effusion,” showed the presence of “fluid,” or were to be “excluded.” Blinded to ear exam results, tympanometry was then completed with record of which Jerger classification tympanogram was found at each frequency.

Results

Although the sensitivity of each test was 1, the specificity of the 1000 Hz tympanometry (100%) in this study was markedly improved compared to the specificity of the 226 Hz tympanometry (71%) (p = 0.016).

Conclusions

This pilot study demonstrated evidence that tympanometry in children with Down syndrome may be more reliable at 1000 Hz than at 226 Hz in detecting the presence of middle ear effusion beyond infancy. Use of the 1000 Hz probe tone yielded fewer false positives for disease (type B tympanograms in the setting of absent middle ear disease). Further studies of a larger patient population are needed to corroborate these results.     

89例瞬态声诱发耳声发射筛查未通过婴幼儿听力学特点分析

目的 探讨听力筛查未通过而短声(click)诱发听性脑干反应阈值正常婴幼儿的听力学特点,进一步分析畸变产物耳声发射(DPOAE)不同频率异常与其他客观听力检查异常之间的关系.方法 瞬态声诱发耳声发射(TEOAE)听力筛查未通过而接受包括DPOAE、短声ABR、40 Hz听觉相关电位、226 Hz声导抗、1000 Hz声导抗和声反射等诊断性听力学检查的患儿共695例,以其中诊断性短声诱发ABR阈值正常的新生儿及婴幼儿89例(123耳)作为研究对象,根据DPOAE频率异常的不同分为A组(全频正常)、B组(低频异常)、C组(高频异常)和D组(全频异常).对比各项听力检查结果,分析DPOAE频率异常各组与其他5项客观听力检查(ABR Ⅰ波潜伏期、40 Hz听觉相关电位、226 Hz鼓室声导抗、1000 Hz鼓室声导抗及声反射)之间的相互关系.结果 123耳中所有6项听力检查均正常者7耳(5.7%);6项听力检查中有一项或一项以上异常者116耳(94.3%).男婴的异常率为93.9%(77/82),女婴的异常率为95.1%(39/41),二者差异无统计学意义(P＞0.05);左耳异常率为93.1%(54/58),右耳异常率为95.4%(62/65),二者差异无统计学意义(P＞0.05).各组耳数所占比例由高到低分别是D组48.0%(59/123)、B组27.6%(34/123)、A组16.3%(20/123)和C组8.2%(10/123).A组、B组和D组中异常率最高的检查项目均为声反射,异常率分别为40.0%,55.9%和66.1%;而C组中异常率最高的项目为ABR Ⅰ波潜伏期(50.0%).各组低频听力损失均以轻度为主,在B组中有1耳为中度听力损失,D组中有6耳为中度听力损失,1耳为重度听力损失.结论 听力筛查未通过而短声ABR反应阈值正常的婴幼儿,如果DPOAE全频异常,需要及时进行全面的听力学评估,而DPOAE全频正常、低频异常或高频异常者,需要进行跟踪随访.

Abstract：

Objective The presnt study was to evaluate the audiological characteristics of infants with normal auditory brainstem response thresholds in click and abnormal transiently evoked otoacoustic emissions. Relationships between test results of distortion product otoacoustic emissions(DPOAE) and other hearing testing methods were also evaluated. Methods The participants consisted of eighty-nine infants,with a total of 123 ears. All participants' TEOAE screening results were abnormal but diagnostic click ABR results were normal. The participants were classified into the following goups based on the test results from distortion product otoacoustic emissions: group A (normal all-frequency ), group B (abnormal lowfrequency), group C (abnormal high-frequency ), and group D (abnormal all-frequency ). Results Obtained from these groups were compared to results of other hearing tests including the latency of ABR wave Ⅰ, 40 Hz auditory event related potential (40 Hz AERP), 226 Hz and 1000 Hz tympanometry, and acoustic reflex. Results In six hearing tests in the 123 ears, seven ears (5.7%) were normal, while 116ears (94. 3% ) were abnormal. No significantly differences were detected between boys (93.9%) and girls (95. 1% ), as well as between left (93. 1% ) and right ears (95.4%). The proportion of abnormal test results ranked as follows: 59 ears in group D (48.0%), 34 ears in group B (27.6%), 20 ears in group A (16. 3% ), and 10 ears in group C (8.2%). The highest abnormal rates in groups A, B and D were acoustic reflex, which were 40. 0% for group A, 55.9% for group B and 66. 1% for group D respectively.The highest abnormal rate in group C was the latency of ABR wave Ⅰ ( 50. 0% ). Distribution of lowfrequency hearing loss in each group was mainly mild. However, one ear in group B was moderate hearing loss, six ears in group D were moderate hearing loss, and one ear in group D was severe hearing loss.Conclusions The present study showed that, of which infants with normal thresholds of ABR failed the hearing screening, comprehensively audiology assessment is needed. And of which infants with normal DPOAE in full frequency or abnormal in high frequency region or low frequency region need to be followed up.     

Quantitative analysis of cochlear active mechanisms in tinnitus subjects with normal hearing sensitivity: multiparametric recording of evoked otoacoustic emissions and contralateral suppression

Objective

Aim of this study was to investigate the possible role played by outer hair cells and cochlear efferent system functionality when tinnitus develops in normal hearing ears. A multiparametric approach was used, entailing recording and analysis of a set of otoacoustic emissions (OAEs): distortion product (DPOAEs), transient evoked (TEOAEs) and efferent-mediated TEOAE suppression in the presence of contralateral acoustic stimulation (CAS).

Methods

Fifty-four subjects with normal hearing sensitivity participated in the study. Twenty-three suffered from chronic subjective tinnitus whereas thirty-one did not have tinnitus and acted as control subjects. DPOAEs were measured with eliciting tones of frequency ratio 1.22 and intensity 65 and 55 dB SPL in the frequency range 0.5–8 kHz. TEOAEs were recorded with the ‘linear’ protocol using clicks at 60 dB peak SPL both in the absence and in the presence of CAS at two different intensities. DPOAE amplitude, TEOAE amplitude, and TEOAE suppression were analysed as relevant parameters.

Results

Significantly reduced DPOAE amplitude in the frequency range 1.5–8 kHz, lower TEOAE amplitude, and slightly decreased TEOAE suppression were measured in tinnitus subjects compared to non-tinnitus controls. In particular, 74% of tinnitus subjects exhibited abnormal DPOAEs, 13% had abnormal TEOAEs, whereas abnormal TEOAE suppression was found in 9% of patients.

Conclusion

Overall, the present work revealed the presence of abnormal OAEs, in particular at higher frequencies, in tinnitus subjects with normal hearing sensitivity. A minor (i.e., sub-clinical) outer hair cell dysfunction, particularly in high-frequency cochlear regions, might thus be assumed in normal hearing tinnitus subjects. In order to better put in light the possible role played by outer hair cells in low-frequency cochlear regions, or by the cochlear efferent system, additional analyses would be needed.     

2062例婴儿的听力检查结果分析

目的探讨3～6月龄婴儿听力障碍的诊断方法。方法对2005年1月～2007年6月在上海交通大学医学院附属上海儿童医学中心就诊的2062例(4124耳)3～6月龄婴儿有选择地进行客观听力测试,包括听性脑干反应(ABR)、畸变产物耳声发射(DPOAE)、声导抗等检查,3月龄时诊断为听力异常者6月龄时复查,收集、分析两次听力测试的资料。结果3月龄时13例(20耳)ABR异常、DPOAE正常,504例(825耳)ABR、DPOAE均异常;ABR异常的845耳中,482例(808耳)(37耳失访)6月龄时复查示:13例(20耳)ABR异常、DPOAE正常,406例(702耳)ABR、DPOAE均异常,47例(64耳)ABR、DPOAR均正常,16例(22耳)ABR正常,DPOAR异常;比较两次检查结果显示:698耳(86.4%)听力无变化,90耳(11.1%)听力改善,20耳(2.5%)听力下降;在ABR反应阈正常、DPOAE未通过者中有438耳同时行226Hz及1000Hz探测音声导抗测试,1000Hz探测音声导抗异常183耳(41.8%),226Hz探测音声导抗异常6耳(1.37%)。结论3～6月龄婴儿的听力诊断必须结合ABR、OAE检查结果综合分析判断,必要时进一步行高频声导抗检查;0～6月龄婴儿中耳功能的检查,运用1000Hz探测音声导抗比226Hz的更敏感;对确诊听力障碍者,尤其是有听力障碍高危因素者,必须密切随访,警惕听力波动及进行性的听力下降。     

Comparison of auditory steady-state responses and auditory brainstem responses in audiometric assessment of adults with sensorineural hearing loss

Objective

Many of the medico-legal patients who claimed compensation may exaggerate hearing loss that varies in degree, nature, and laterality. The purpose of this study was to investigate whether Auditory Steady-State Response (ASSR) could be used to predict the hearing level of adults, and whether ASSR could become a better testing method than Auditory brainstem response (ABR) in audiometric assessment of adults with sensorineural hearing loss.

Methods

This was a prospective study, which was conducted in a tertiary referral hospital. From January to June 2007, 142 subjects (284 ears) with varying degrees of sensori-neural hearing impairment were included in this study. Four commonly used frequencies (500, 1000, 2000, 4000 Hz) were evaluated. All subjects received pure-tone audiometry, multi-channel ASSR, and ABR tests for threshold measurement. The correlation of pure tone thresholds with ASSR and ABR thresholds were assessed.

Results

Between multi-channel ASSR and pure tone thresholds, a difference of less than 15 dB was found in 71% while a difference of less than 25 dB was found in 89% of patients. The correlation coefficient (r) of multi-channel ASSR and pure tone thresholds were 0.89, 0.95, 0.96, and 0.97 at 500, 1000, 2000, and 4000 Hz, respectively. The strength of the relationship increased with increasing frequency. On the other hand, between ABR and pure-tone thresholds, a difference of less than 15 dB was found in 31%; a difference of less than 25 dB was found in 62% of patients. The r correlation value for ABR and pure tone thresholds was 0.83.

Conclusion

ASSR is a more reliable test for the accurate prediction of auditory thresholds than ABR. It can be a powerful and convenient electro-physiologic examination tool for clinically assessing of adults with sensorineural hearing loss.     

足月正常新生儿多频探测音鼓室声导抗正常值测定

目的：探讨正常新生儿多频探测音鼓室声导抗图的图型、声导纳值、声纳值和声导值的正常范围。方法：使用GSI-33中耳分析仪,对足月顺产并通过瞬态诱发性耳声发射和畸变产物耳声发射筛查的新生儿55例（110耳）进行226、6781、000 Hz探测音鼓室声导抗测试,对比分析各种探测音鼓室声导抗的图形,声导纳值、声纳值和声导值,并进行统计学分析。结果：226 Hz探测音鼓室声导纳图、声纳图和声导图以双峰型为主,分别占90.0%、99.1%和85.5%,少数为单峰型,无多峰型出现;678 Hz探测音鼓室声导纳图、声纳图和声导图以单峰型为主,分别占62.7%、77.3%和62.7%,双峰型分别占34.6%、20.9%和31.8%,少数出现三峰型;1 000 Hz探测音鼓室声导纳图、声纳图和声导图以单峰型为主,分别占96.4%、99.1%和97.3%,极少数为双峰型,无三峰型出现。226 Hz与678 Hz探测音测试,鼓室声导纳值与声纳值、声纳值与声导值的均差异有统计学意义（均P〈0.05）;声导纳值与声导值差异无统计学意义（P〉0.05）。1 000 Hz探测音测试,鼓室声导纳值、声纳值与声导值的两两比较均差异有统计学意义（均P〈0.05）。结论：获得正常新生儿多频探测音鼓室声导抗图的图形、声导纳值、声纳值和声导值的正常范围,结果提示,1 000 Hz探测音鼓室声导抗测试可以较好反映正常新生儿的中耳功能。     

低频和高频探测音鼓室声导抗测试在婴儿中耳功能诊断中的作用

目的评价低频和高频探测音鼓室声导抗测试在诊断婴儿中耳功能异常中的作用。方法使用GSI Tympstar中耳分析仪，对年龄5—25周的听性脑干反应（auditory brainstem response，ABR）检查正常婴儿15例（30耳）和Ⅰ波潜伏期延长提示可能存在中耳功能异常婴儿17例（20耳），进行226、678、1000Hz探测音鼓室声导抗测试的比较。结果226Hz探测音鼓室声导纳图的静态声导纳值、图形、峰压和梯度在2组间的差异无统计学意义。678Hz探测音鼓室声导纳图、声纳图及声导图在2组中均可见无峰型、单峰型、双峰型、三峰型图形，其与ABR检查的一致率分别为70．0％、58．0％、64．0％，kappa值分别为0．324、0．234、0．118。1000Hz探测音鼓室声导纳图、声纳图及声导图在正常组中单峰型分别为28耳（93．3％）、25耳（83．3％）、26耳（86．7％），在异常组中无峰型分别为15耳（75％）、17耳（85％）、13耳（65％），其与ABR的一致率分别为90．0％、92．0％、86．0％，kappa值分别为0．783、0．831、0．690。结论1000Hz探测音鼓室声导抗测试是诊断小于25周婴儿中耳功能的较准确的检查方法，226、678Hz探测音鼓室声导抗测试则不能提供这些婴儿中耳功能的准确的信息。     

Non-organic hearing loss in Chinese teenagers

Objective

To heighten the physician's awareness of non-organic hearing loss in teenagers in China.

Methods

Retrospective cases review of seven patients (six girls and one boy) with sudden hearing loss was conducted.

Results

Five patients presented with hearing loss bilaterally and two patients unilaterally. All patients suffered from severe to profound hearing loss. However, the acoustic reflex test indicated direct and indirect responses were present bilaterally at 1000 Hz 100 dB SPL. The results of ABR test revealed hearing threshold within 20–30 dB nHL. Further investigations indicated non-organic hearing loss was associated with school stress or environment conflict. Satisfactory outcomes were achieved in all patients.

Conclusion

Non-organic hearing loss should be considered when teenagers present with severe to profound sudden hearing loss if the acoustic reflex is present. School and home stresses are associated with the occurrence of non-organic hearing loss in the present study.     

Impedance audiometry in infants with a cleft palate: The standard 226-Hz probe tone has no predictive value for the middle ear condition

Objective

Infants with a cleft palate and microscopical evidence for middle ear effusion attracted our attention because of normal tympanometry results and negative otoacoustic emissions. These contradictory findings initiated us to study to what extent high frequency tampynometry is able to supply us with more reliable results.

Methods

Eighty-three ears of 46 cleft palate babies aged between 2 and 7 months were examined within the pedaudiological screening procedure via tympanometry before their surgical cleft closure. We applied probe tone frequencies of 226 Hz and 678 Hz. A control cohort of 69 ears of 36 babies without cleft palate was established. Results were later compared to the intraoperative findings.

Results

By tympanometry with a 226-Hz probe tone, the examiners predicted the intraoperative findings correctly in only 29 cases of 83 examined ears (34.9%). However, their interpretation of tympanometry results by means of a 678-Hz probe tone correlated to the intraoperative findings in 96.3% cases.

Conclusions

In cleft palate babies tympanometry with a 678-Hz probe tone yields clear evidence of middle ear effusion and should therefore serve as an essential instrument before the first surgical step of palate closure. In case of applying the 226-Hz probe tone, we were often confronted with normal function of the Eustachian tube despite of proved existence of middle ear effusion.     

Wideband energy reflectance findings in presence of normal tympanogram in children with Down's syndrome

Objectives

The prevalence of middle ear disorders in children with Down syndrome is higher than normal children due to the associated craniofacial abnormalities. The goal of this study is to evaluate middle ear function using wideband energy reflectance at ambient pressure in 14 young children with Down syndrome and matched control group (2½-5 years old; N = 19 ears per group) who each have a normal 226 Hz tympanogram.

Methods

All children underwent otoscopic examination, hearing screening using play audiometry (500-4000 Hz), and middle ear testing using 226 Hz tympanometry and wideband energy reflectance. The chirp signals for the wideband energy reflectance were presented to the child's ear at 65 dB SPL stimulus level and the recording was done over 220-8000 Hz range. The measured energy reflectance represents the ratio of the sound energy reflected from the tympanic membrane to the incident sound energy transmitted to the middle ear at a specific frequency. Paired Samples t-test was computed for the mean, 95th, 75th, 25th, and 5th percentile data of each frequency of the two groups.

Results

Despite the presence of normal tympanometric findings in both groups, results revealed abnormal wideband energy reflectance findings in 63% of the children with Down syndrome compared to the normal wideband energy reflectance findings in the control group. The mean energy reflectance ratio of the Down syndrome group was abnormally lower than that of the control at 5700-8000 Hz (p < 0.0005). The 5th and 95th percentile ratios of the Down syndrome group fell outside the 5th and 95th percentile of the control group (p < 0.0005).

Conclusions

Abnormally low energy reflectance ratios above 4000 Hz in the presence of normal tympanograms in the Down syndrome group may suggest associated congenital middle ear anomalies in children with DS. The present findings suggest that wideband energy reflectance has the potential to be of more practical value in children with DS than tympanometry. Further research with a larger number of Down syndrome children will illuminate the potential of wideband energy reflectance in diagnosing middle ear disorders in children with Down syndrome.     

耳声发射异常听性脑干反应正常的婴幼儿听力学分析

目的 探讨听力筛查异常而听性脑干反应(auditory brainstem response,ABR)正常的婴幼儿的听力学特点.方法 以瞬态声诱发性耳声发射听力筛查未通过而ABR正常的新生儿及婴幼儿53例(81耳)作为研究对象,对比各项听力检查结果,分析ABR与其他检查(40 Hz听觉相关电位、听觉稳态诱发反应、畸变产物耳声发射、鼓室声导抗及声反射)之间的相互关系.结果 81耳中所有检查结果均正常18耳(22.2%);其中至少有一项检查异常共63耳(77.8%).40Hz听觉相关电位和听觉稳态诱发反应分别测试36耳和45耳,异常分别为14耳(38.9%)和27耳(60.0%);畸变产物耳声发射测试68耳,异常50耳(73.5%);鼓室声导抗测试50耳,异常9耳(18.0%);声反射测试47耳,异常27耳(57.4%).结论 单纯以ABR作为婴幼儿听力正常的判断标准尚存在不足,综合的听力学评估非常有必要.     

Wideband acoustic absorbance in children with Down syndrome

Introduction

Tympanometry is currently the most frequently used tool for assessing the status of the middle ear, commonly assessed using a single 226 Hz tone. However, the use of the Acoustic Immittance Measures with a wideband stimulus is a promising high-resolution evaluation, especially in individuals known to have middle ear alterations, such as Down syndrome patients.