儿童chirp听性脑干反应与行为测听的相关性

目的 采用chirp信号作为声刺激进行听性脑干反应(ABR)测试,观察chirp ABR阈值与行为测听的相关性,探讨chirp ABR作为儿童临床客观听力评估的可行性.方法 选择2007年8月至9月佛山市听觉语言康复中心的听力障碍儿童和广州市儿童医院听力门诊的正常听力儿童共22例(共35耳)作为研究对象,分别进行行为测听和chirp ABR测试,并对chirp ABR反应阈和行为测听阈值进行Pearson相关性分析.结果 22例接受测试儿童中男14例,女8例,年龄3.3～6.5岁,平均年龄4.8岁.纳入研究的35耳中,正常听力6耳,听力损失轻度2耳、中度4耳、重度10耳、极重度13耳.行为测听0.5、1、2、4 kHz平均听阈与chirp ABR阈值,0.5 kHz听阈与L-chirp ABR阈值,1～4kHz平均听阈与U-chirp ABR阈值之间的相关系数分别为0.939,0.900及0.930,P值均<0.05.结论 chirp ABR作为一种客观测听技术,能够较好地反映儿童的听力水平,有希望应用到临床工作中.     

Comparison of threshold estimation in infants with hearing loss or normal hearing using auditory steady-state response evoked by narrow band CE-chirps and auditory brainstem response evoked by tone pips

Objective: The objective of this study is to compare air-conduction thresholds obtained with ASSR evoked by narrow band (NB) CE-chirps and ABR evoked by tone pips (tpABR) in infants with various degrees of hearing loss. Design: Thresholds were measured at 500, 1000, 2000 and 4000?Hz. Data on each participant were collected at the same day. Study sample: Sixty-seven infants aged 4 d to 22 months (median age?=?96 days), resulting in 57, 52, 87 and 56 ears for 500, 1000, 2000 and 4000?Hz, respectively. Results: Statistical analysis was performed for ears with hearing loss (HL) and showed a very strong correlation between tpABR and ASSR evoked by NB CE-chirps: 0.90 (n?=?28), 0.90 (n?=?28), 0.96 (n?=?42) and 0.95 (n?=?30) for 500, 1000, 2000 and 4000?Hz, respectively. At these frequencies, the mean difference between tpABR and ASSR was ?3.6?dB (±?7.0), ?5.2?dB (±?7.3), ?3.9?dB (±?5.2) and ?5.2?dB (±?4.7). Linear regression analysis indicated that the relationship was not influenced by the degree of hearing loss. Conclusion: We propose that dB nHL to dB eHL correction values for ASSR evoked by NB CE-chirps should be 5?dB lower than values used for tpABR.     

Prediction of hearing threshold in infants using auditory steady-state evoked potentials

This retrospective study examines the relationship between auditory steady-state evoked potential (ASSEP) thresholds determined in infancy and subsequently obtained behavioral hearing levels in children with normal hearing or varying degrees of sensorineural hearing loss. Overall, the results from 211 subjects showed that the two test techniques were highly correlated, with Pearson r values exceeding .95 at each of the audiometric test frequencies between 500 and 4000 Hz. Analysis of the findings for babies with significant hearing loss (moderate to profound levels) showed similar threshold relationships to those obtained in previous studies involving adults and older children. The results for infants with normal or near-normal hearing did, however, differ from those reported for older subjects, with behavioral thresholds typically 10 to 15 dB better than would have been predicted from their ASSEP levels.     

正常新生儿和婴儿的短音听性脑干反应和听觉稳态反应

目的 建立听力正常婴儿短音听性脑干反应(tone-pip ABR)和听觉稳态反应(auditorysteady state response,ASSR)反应阈的正常参考值,研究其听觉发育的生物学规律,并比较两种听力检测技术的频率特性.方法 选取0～6月龄听力正常婴儿80例(160耳),按月龄分为四组:新生儿组、42 d组、3月龄组和6月龄组,每组20例(40耳),男女例数均等,分别记录其短声ABR的潜伏期及在0.25、0.5、1、2、4、8 kHz频率范围内tone-pip ABR和ASSR的反应阈.结果 在70 dB正常听力级短声刺激下,短声ABRⅠ、Ⅲ、Ⅴ波潜伏期、Ⅰ～Ⅲ、Ⅲ～Ⅴ、Ⅰ～Ⅴ波间期随月龄增加逐渐缩短,波Ⅰ于42 d前、波Ⅲ于3个月前发育变化显著.tone-pip ABR波形与短声ABR相似,Ⅰ、Ⅲ、Ⅴ波潜伏期随频率增加逐渐缩短,波形分化逐渐清晰.不同频率、不同月龄tone-pip ABR和ASSR反应阈差异具有统计学意义(P值均＜0.05).除0.25 kHz外,其余频率tone-pip ABR反应阈均低于ASSR.不同月龄tone-pip ABR和ASSR听力曲线形状相似.结论 0～6月正常婴儿tone-pip ABR的潜伏期和波间期随月龄增加逐渐缩短,而反应阈无明显变化.tone-pip ABR和ASSR均有稳定的频率特异性,tone-pip ABR反应阈低于ASSR,可能更接近主观纯音听阈.     

婴幼儿短纯音与短声诱发的听性脑干反应初探

目的分析婴幼儿短纯音诱发的听性脑千反应（tone burst click auditory brain stem response, TB-ABR）与短声诱发的听性脑千反应（click auditory brain stem response, C-ABR）阈值的相关性,以探讨TB—ABR在婴幼儿客观听力评估中的临床应用价值。方法对2007年1月-2009年1月,新生儿听力筛查通过且C—ABR阈值正常者27例（54耳）,以短纯音为刺激声,进行ABR波V反应阈值及潜伏期测试,并与C-ABR作差异与相关性分析。结果本组27例（54耳）婴幼儿中完成4个频率TB-ABR测试的共27例（54耳）,0．5、1、2、4kHz TB—ABR波V反应阈值分别为（40．0±11．6）dBnHL、（36．7±9．0）dBnHL、（27.2±6．7）dBnHL和（25．9±6．3）dB nHL,明显高于C-ABR阈值（17．8±6．4）dBnHL（P〈0．05）,TB-ABR波V反应阑值随着刺激声频率的升高而下降,潜伏期随着刺激声频率的升高而缩短。0．5、1、2及4kHz1BABR反应阈与GABR反应阈的线性相关系数分别为0.53、0．60、0.67、0．72,存在直线正相关关系（P〈0．01）。结论婴幼儿TB-ABR和C-ABR反应阈之间存在相关性,且高频相关性优于低频,TB-ABR可作为一种具有频率特异性的婴幼儿客观听力评估方法。     

Maturation of auditory function related to hearing threshold estimations using the auditory brainstem response during infancy

Objective

The objective of this study was to quantify the maturation of the Auditory Brainstem Response (ABR) at discrete periods during infancy and to provide a means to appropriately estimate hearing thresholds when the ABR is immature.

Methods

A longitudinal study was designed to measure the in situ ABR thresholds of infants using air-conduction tone bursts of 500, 2000 and 4000 Hz. Thresholds were measured using an eardrum-level microphone to eliminate the bias related to coupler-referenced scales such as the dB nHL scale used for adult assessments.

Results

The study found that the in situ thresholds of a sample of normally developing infants decreased significantly during the first 6 months of life. A comparison of these in situ thresholds with those of normal-hearing adults revealed that the ABR response reached maturity in these infants between 4 and 6 months of age for the frequencies 500 and 2000 Hz but remained immature, or elevated, at 6 months of age for 4000 Hz.

Conclusions

The maturation of the ABR should be considered during the estimation of an infant's audiogram and subsequent diagnosis.     

Normative auditory brainstem response data for hearing threshold in the rabbit

In an experimental study, we determined the physiological hearing threshold of the rabbit in order to use these data as normative values for further experimental investigations. The aim was to use different acoustic stimuli (click and tone-pip stimuli) with different frequency spectra for air and bone conduction (BC) in order to obtain further information about the optimal form of stimulus when recording auditory evoked potentials in the rabbit. For the investigation, we used 46 female New Zealand rabbits weighing 3.2-4.4 kg and aged 6 months. The equipment used to record brainstem auditory evoked potentials was the Nicolet Viking IV P System (Nicolet Biomedical, Inc.). In accordance with the experimental set-up, the measurements took place under intubation anesthesia, with a total of four repeat measurements performed on each ear at different times. Tone-pip and click stimuli with varying intensities of stimulus, transmitted via air conduction and BC, were applied. The I-IV waves proved the most stable for both stimulus modalities. They were registrable in 98.7% of cases, whereas only 30.2% of the V waves could be recorded. Values averaged from all measurements made throughout the study yielded a potential threshold of 34.8 dB peak equivalent (p.e.) SPL for the click stimulus, 13.8 dB p.e. SPL for the tone-pip stimulus at 8 kHz and 34.2 dB p.e. SPL for the click stimulus transmitted via BC. With regard to latencies, the results indicated a good reproducibility through different stimuli with acceptable standard deviations. The values for physiological hearing threshold obtained here can serve as normative data in subsequent experimental animal studies.     

Tone burst stimulus for auditory brainstem responses: Prediction of hearing threshold at 1 kHz

Objective

To assess differences in hearing threshold estimation of four different ABR tone-bursts at 1 kHz.

Methods

Twenty-one (21) ears from 11 subjects were tested with pure-tone audiometry (PTA): 5 ears (24%) were normal hearing, 5 (24%) affected by mild hearing loss, 7 (33%) showed moderate hearing loss and 4 (19%) severe hearing loss. After PTA each subject underwent tone-burst ABR test at 1 kHz using a linear gated (L_ABR) or Blackman windowed (B_ABR) stimuli with (nn_ABR) and without ipsilateral notched noise. Stimulation rate and filters settings were unchanged.

Results

Overall correlation between PTA and all ABRs thresholds was high, ranging from 0.84 to 0.94. In normal hearing ears none of the differences was significant, except for those measured with B_nn_ABR, which showed a mean 16 dB overestimation of the pure-tone threshold (p < 0.05). In mild hearing loss group none of the differences between thresholds were significant. In moderate and severe hearing loss groups significant differences were measured with L_nn_ABR (p < 0.05) with a mean 7.5 dB underestimation of PTA.

Conclusions

Although very similar, some significant differences were found when considering specific group of patients with different degrees of hearing loss.     

婴幼儿听觉脑干诱发电位的正常值

目 的探讨0～2岁婴幼儿听觉脑干诱发电位的正常值。方法 采用听觉脑干诱发电位（BAEP）对37例无耳科疾患的听力正常婴幼儿进行检查，测量Ⅰ．Ⅲ．Ⅴ波峰潜伏期和Ⅰ～Ⅲ．Ⅲ～Ⅴ峰间间期。结果 2岁组的各波峰潜伏期较1月龄组明显缩短，呈非常显著性差异（P〈0．001）；而各年龄组的Ⅰ～Ⅲ峰间潜伏期无明显差异（P〉0．05），2岁组的Ⅲ～Ⅴ峰间间期较1月龄组缩短，有显著差异（P〈0．05）。结论 随着年龄的增长，听觉脑干诱发电位的各波峰潜伏期逐渐缩短，但整个听觉通路的发育可能并不是完全平行的。     

Neonatal hearing screening using the auditory brainstem response

A targeted screen of babies at risk of having a sensorineural hearing loss (SNHL) using the auditory brainstem response has been in place since 1987 in Bradford and Airedale. The aims of this paper were to ascertain what proportion of a 4-year cohort of children with SNHL should have been identified by the programme; was identified by the programme; and the reasons for failing when children were missed. The cohort of 49 children had moderate to profound SNHL (> 50 dB) and were born between 1 April 1991 and 31 March 1995. Although 92% had at risk factors (higher than in other series), 80% was the maximum that could have been prospectively detected by the programme and only 37% were actually diagnosed as a result of the screening programme. Apart from a generalised under-recruitment, children with risk factors arising because of in utero, perinatal and postnatal events (as opposed to family history, craniofacial abnormalities and syndromes) tended to be missed (P < 0.01). The overall yield of the screening programme was 0.5/1000/year. While the yield of a universal neonatal screening programme based on otoacoustic emissions should be double this, a targeted infant distraction test later in infancy will be an essential backup. Improved liaison with paediatricians in particular as well as simplification of the referral criteria should improve targeting children at risk.     

听性脑干反应与40Hz听觉相关电位综合评估听觉阈值

目的 探索应用听性脑干反应(auditory brain stem response,ABR)和40Hz听觉相关电位(40Hz auditory event related potential,40Hz AERP)来客观评估听阈的最佳方法.方法 对120例受试者分别测出其平均听阈和ABR阈值、40Hz AERP阈值,共获得资料可靠完整的86耳用于实验分析.将86耳根据听力曲线的类型分为下降型29耳、上升型20耳和水平型37耳三种.用SPSS软件分别对3组数据进行统计学处理,并进行多元回归分析,建立三种数学模型,并进行简化和检验.最后另选10例新的受试者对得到的公式进行均方差可靠性检验.结果 3组平均听阈与ABR阈值和40Hz AERP阈值具有显著线性相关性(r2=0.932,0.944,0.934).建立的三种模型分别为:水平型,平均听阈=ABR阈值;下降型,平均听阈=1/3(40HzAERP) 2/3ABR;上升型,平均听阈=2/3(40HzAERP) 1/3ABR.均方差检验显示公式法优于ABR法.结论 利用ABR阈值和40Hz AERP阈值通过三种回归方程较单纯应用ABR阈值能够更准确的估计受试者的平均听阈,可以尝试用于评估婴幼儿及不能主动配合的受试者的听阈.     

A frequency-specific auditory brainstem response technique exemplified in the determination of age-related auditory thresholds

Using gated sinusoidal stimuli (tone bursts), frequency-specific auditory brainstem responses (ABR) have been recorded in mice. The gating function represents a filter with a constant narrow bandwidth in the investigated frequency range 2-31.5 kHz. The ABR thresholds found in the CBA/CBA mouse using this technique were in close agreement with those previously reported in the literature concerning mice. The ABR thresholds were analysed in 2-18-month-old animals showing a slight impairment of ABR thresholds with increasing age. The individual variations in ABR thresholds were small.     

Automated system for screening hearing using the auditory brainstem response

Routine screening of hearing using the auditory brainstem response (ABR) in infants, such as neonates in the special care baby unit, requires a system which is quick, user-friendly and gives a simple outcome. A system which consists of a stimulator/amplifier unit for recording the ABR controlled by a standard Master Series BBC Microcomputer is described which fulfils these requirements. The test procedure is highly automated, and a pass or refer decision for the screen on each ear is given by a machine-scoring algorithm which detects the ABR waveform.     

多频听觉稳态反应评估听力正常青年人骨导听阈的研究

目的 探讨多频听性稳态反应（MASSR）评估听力正常青年人骨导纯音听阈的可能性,旨在观察听力正常青年人骨导多频听觉稳态反应（ASSR）测试的正常值特点,进一步探讨骨导ASSR的反应阈与骨导纯音听阈的相关性,为临床上对不能配合做纯音测听的患者行听力评估时提供客观参考。方法 对20例（男10例、女10例）听力正常青年人进行骨导ASSR 及骨导纯音听阈检查,记录0.5、1.0、2.0、4.0kHz反应阈及行为听阈,比较二者间的相关性。结果 骨导ASSR 反应阈男组、女组间差异无统计学意义;各频率间骨导ASSR 反应阈比较,4.0kHz较其它各频率差异有统计学意义（P＜0.001）,0.5、1.0、2.0kHz三个频率间差异无统计学意义（P＞0.05）。骨导ASSR 反应阈与骨导纯音听阈在0.5、1.0、2.0、4.0kHz四个频率处相关系数分别为0.95、0.91、0.26、0.29。结论 骨导ASSR反应阈与骨导纯音听阈间只有在0.5、1.0kHz时有较好的相关性,高频的骨导ASSR与骨导纯音听阈差异性比较大,因此目前还不能广泛用于临床评估高频骨导纯音听阈。     

Low-frequency specificity of the auditory brainstem response threshold elicited by clicks masked with 1590-Hz high-pass noise in subjects with sloping cochlear hearing losses.

In this study, the frequency specificity of the ABR threshold to stimulation with a click masked with 1590-Hz high-pass noise was determined in subjects with sloping cochlear hearing losses both high- and low-frequency in character. The results show that the ABR threshold elicited by this stimulus is low-frequency specific. The standard error in estimating the 1,000-Hz pure-tone threshold from the high-pass-noise-masked click-evoked ABR threshold is 10.2 dB which equals that for estimating the 3,000-Hz pure-tone threshold from the routinely used unmasked click ABR threshold. The ABR threshold elicited by a click masked with 1590-Hz high-pass noise can therefore be regarded as an accurate tool to predict the pure-tone hearing loss at 1,000 Hz. However, this method is less suitable for routine clinical testing because of the masking noise needed: the occasional high loudness level adversely affects the response quality and reduces the dynamic range of pure-tone hearing losses to be assessed. A third disadvantage is that determining the masking level electrophysiologically for each ear is time consuming. The search for a method with no or less masking noise should therefore continue.     

Prediction of auditory nerve survival in humans using the electrical auditory brainstem response.

This investigation studied the electrical auditory brainstem response (EABR) input-output functions in three groups of patients: individuals with normal auditory neural systems; patients with acquired, profound sensorineural hearing loss; and patients with congenital, profound sensorineural hearing loss. Each input-output function was obtained in the operating room under general anesthesia and with the patient paralyzed to eliminate myogenic contamination. In contrast to the acoustically elicited ABR, the EABR waveforms were characterized by a dominant early wave corresponding in latency to wave II. This wave was much larger and often appeared at lower stimulus intensities than wave V. The results, plotted according to rate of growth for waves II and V, showed that normal subjects generally had larger, more robust early waves than either hearing impaired group. Little difference was noted in the amplitudes or rates of growth for wave V among the three groups. Based on these observations, we concluded that the EABR demonstrated differences in the way normal and impaired systems respond to electrical stimulation. In addition, the EABR may be useful in providing a qualitative prediction of neural survival into broad categories of many surviving neurons versus a marked reduction in ganglion/neuronal density.     

成人感音神经性聋听觉稳态诱发反应阈值与纯音听阈值比较

目的：测定成人感音神经性聋患者听觉稳态诱发反应（ASSR）和纯音听阈值,为临床诊断提供客观依据。方法：选成人感音神经性聋患者33例（65耳）,行ASSR阈值纯音听测试。结果：ASSR、纯音听阈值对比有统计学意义,听阈有显著相关性,0．5、1．0、2．0、4．0kHz频区间相关系数分别为：0．769、0．772、0．743、0．756。ASSR阈值较行为阈值高,ASSR阈值与纯音听阈间差值多在3．0～10．0dB HL之间。在0．5、1．0、2．0、4．0kHz频区间分剐为：4．77、8．83、6．49、3．67dB HL,随频率增高,两者的差异有缩小趋势。结论：成人感音神经性聋患者ASSR阈值与纯音听阈间对比有统计学意义,通过测试ASSR阈值可推断出被检查者纯音听阈的阈值。     

Age-related hearing changes and effects of exotoxin on inner ear function in aging rat. A frequency-specific auditory brainstem response study

Frequency-specific auditory brainstem responses to tone bursts (2-31.5 kHz) and tuning curves were recorded in 8 male rats during their entire life. No significant threshold elevation occurred during the 1st year. Mean age at onset of hearing loss was 20 months, with individual variations ranging from 14 up to 23 months. In most animals, threshold elevations were limited to 20 and 31.5 kHz. At age of 18-23 months, 3 rats were treated with Pseudomonas aeruginosa exotoxin A. After instillation, threshold elevation occurred at all frequencies, followed by near-total recovery at low frequencies, but only partial reversibility at high frequencies. It is concluded that aging-related hearing changes in Sprague-Dawley albino rats start at different ages, particularly comprising high frequencies and encroaching on the middle and low areas with increasing age.     

State of the art neonatal hearing screening with auditory brainstem response

The purpose of this paper is to briefly review some of the aspects of the auditory brainstem response (ABR) that are important in its use as a method of screening and assessing hearing in the neonate. The paper starts by considering the technical limitations of click ABR and explores the alternative electrophysiological methods. It then considers where ABR is required in the screening of neonates. The role of bone conduction ABR in estimating the conductive component of any hearing loss is discussed. Finally, the ability of the neonatal ABR to predict the long-term audiometric outcome of permanently hearing-impaired children is considered.