儿童孤独症患者脑干听觉诱发电位改变的初步观察

目的：通过观察儿童孤独症患者患者脑干听觉诱发电位的改变,探讨听觉诱发电位检测在听觉障碍儿童孤独症诊断中的临床意义。方法：按DSM－IV诊断标准确诊的15例孤独症患儿的14例正常对照组,同期接受听觉诱发反应检测,比较两组间波Ⅰ-Ⅴ各波峰潜伏期,波峰潜伏期差和波幅的差异。结果：孤独症患儿左侧波Ⅴ、右侧波Ⅱ峰间潜伏期和右侧Ⅰ－Ⅲ、Ⅰ－Ⅴ峰间潜伏期差较对照组显著延长（P＜0．05－0．005）,孤独症组右侧波Ⅲ振幅较对照组增高（P＜0．05）,其他各指标两组间无显著性差异,结论：孤独症患儿脑干听觉诱发电位的突出改变是潜伏期有延长的趋势,对就诊于耳鼻咽喉科的听阈正常而有听觉障碍,言语交往能力着,脑干听觉诱发电位检查潜伏期延长的儿童,应警惕孤独症或其他神经精神发育障碍。     

孤独症儿童脑干听觉诱发电位及耳声发射研究

目的探讨孤独症对听觉系统功能的影响,为临床诊治提供理论依据。方法对20例孤独症患儿进行听觉脑干诱发电位（auditory brainstem response,ABR）及畸变产物耳声发射（distortion Product otoacoustic emission,DPOAE）测试,设立同年龄段正常组进行对照研究。结果①孤独症组ABR双耳Ⅴ波潜伏期、右耳Ⅰ～Ⅴ波间期、Ⅲ～Ⅴ波间期延长,与对照组比较有显著性差异（P〈0．05）;②孤独症组DPOAE异常率增高,1kHz及1．5kHz平均幅值及1kHz引出率降低,与对照组比较有显著性差异（P〈0．05）。结论孤独症儿童ABR潜伏期延长,DPOAE测试异常率增高,提示脑干听觉通路传导异常,可能是引起孤独症儿童广泛感觉系统发育障碍,使言语、认知、社会等方面异常发育的原因之一。     

脑干听觉诱发电位用以检测腭裂患儿听力的评价

目的:评价腭裂患儿脑干听觉诱发电位(BAEP)的异常情况及听力障碍程度、性质.方法:应用脑干听觉诱发电位检测32例腭裂患儿的听觉阈值,各波潜伏期及阈值异常率,潜伏期延长的异常率.结果:腭裂患儿听觉阈值及各波潜伏期较正常儿显著提高和延长(P＜0.01),阈值异常率为68.75%,腭裂患儿普遍存在程度不同的听力障碍,半数以上为中、重度听力障碍.潜伏期延长的异常率为65.6%.患侧耳数Ⅰ、Ⅲ、Ⅴ波延长分别为30耳、18耳、32耳.腭裂患儿Ⅰ～Ⅴ波峰间期较正常儿童明显延长,表明存在一定程度的中枢传导通路功能障碍.不同类型及不同年龄腭裂患儿之间BAEP反应阈及异常率比较差异无显著性(P＞0.05).结论:68.75%腭裂患儿存在听力障碍且大部分是传导性听力丧失,BAEP作为筛选适于低龄儿童听力的工具,具有重要的临床意义.     

80例听阈正常的婴儿BAEP结果分析

目的分析80例V波反应听阈正常的婴儿脑干听觉诱发电位（BAEP）的结果,探讨婴儿正常值与成人的差异以及性别、左右耳对BAEP结果的影响。方法婴儿共80例（160耳）,年龄3~12个月,平均4.3个月;成人共65例（130耳）,年龄18~67岁,平均35.6岁,均行BAEP检查。分析在80 d B声强刺激下I、Ⅲ、V波潜伏期（PL）,I一Ⅲ、Ⅲ一V、I—V波峰间期（IPL）。结果Ⅲ、V波潜伏期及I一Ⅲ、Ⅲ~V、I—V波峰间期婴儿组较成人组明显延长,差异有统计学意义（P〈0.05）;I波潜伏期两组间无明显差异（P〉0.05）。婴儿组内性别间、左右耳间无明显差异（P〉0.05）。结论与成人比较,婴儿III、V波潜伏期及I一Ⅲ、Ⅲ一V、I—V波峰间期相对延长。性别、左右侧耳对BAEP结果亦无显著性影响。提示婴儿听觉传导通路发育不完全,以髓鞘发育差距尤为明显。     

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。     

先天性心脏病患儿短声诱发听性脑干反应的探讨

探讨先天性心脏病(先心病)对患儿脑干发育的影响。方法探讨先心病患儿听性脑干反应 (ABR)，并以正常儿为对照组。结果年龄<12月，青紫型先心病(CCHD)患儿Ⅰ波潜伏期(LP)正常，Ⅰ～V 波峰间潜伏期(IPL)较正常儿显著延长，非青紫型先心病(NCCHD)患儿Ⅰ波LP、Ⅰ～V波IPL均显著延长；4 ～6岁者NCCHD和CCHD无反复缺氧发作者LP和Ⅰ～V波IPL与正常儿无差异，CCHD反复缺氧发作者Ⅰ ～V波IPL较正常儿显著延长，异常率2.3％。结论先心病不延迟婴儿期脑干发育，缺氧发作可损害脑干功 能，对缺氧发作者应尽早进行干预。     

儿童OSAHS不同刺激重复率听性脑干反应的临床研究

目的 探讨儿童阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep Apnea-hypopnea syndrome,OSAHS)的脑干听觉诱发电位反应(Brain Auditory Evoked Potention,BAEP)的特征。方法 对经多导睡眠检测确诊的儿童OSAHS患者87例,经声阻抗检查呈A型曲线,4～7岁,分别以11.1、33.1?Hz的不同刺激重复率进行BAEP测试,比较不同病变程度对两种刺激重复率听觉阈值、潜伏期及波间期差的影响。结果 与对照组比较,OSAHS轻度组：两种刺激重复率的 BAEPⅠ、Ⅲ、Ⅴ波的潜伏期及波间期差均在正常范围,Ⅴ波听阈为25dBnHL;中度组：刺激重复率33.1Hz,Ⅰ、Ⅲ、Ⅴ波的潜伏期及波间期差无异常,Ⅴ波听阈25dBnHL;刺激重复率11.1Hz,Ⅰ、Ⅲ、Ⅴ波的潜伏期延长,差异具有统计学意义（P＜0.05）,Ⅰ～Ⅲ、Ⅰ～Ⅴ波间期延长,Ⅲ～Ⅴ间期在正常范围,Ⅴ波听阈28dBnHL;重度组：刺激重复率33.1Hz,Ⅰ、Ⅲ、Ⅴ波的潜伏期及各波间期差均延长,Ⅴ波听阈35dBnHL;刺激重复率11.1Hz,Ⅰ、Ⅲ、Ⅴ波的潜伏期及波间期差均延长,Ⅴ波听阈40dBnHL。重度OSAHS患者两种刺激重复率各波潜伏期、波间期差听阈改变均具有统计学意义。结论 低频短声刺激能较早反映OSAHS患儿脑干功能的改变;重度OSAHS患儿的BAEP测试结果异常,提示OSAHS对听阈及听觉脑干传导功能都存在影响。     

1～6月龄正常婴儿听性脑干反应检测结果分析北大核心CSCD

目的探讨1～6月龄正常婴儿听性脑干反应（ABR）的变化规律,建立小婴儿ABR波I、III、V潜伏期及波间期正常参考值。方法对166例（269耳）1月龄、141例（226耳）2月龄、111例（177耳）3月龄、58例（96耳）4月龄、78例（121耳）5月龄和45例（76耳）6月龄正常婴儿进行短声（click）ABR测试,分析反应阈及各波潜伏期、波间期。结果1～6月龄正常婴儿ABR反应阈均值为16．18±5．35dBnHL,波V潜伏期均值9．03±0．49ms,各月龄组反应阈差异无统计学意义（P〉0．05）。在80dBnHL刺激声强度时,波I、III、V引出率均为100％,随着刺激声强的降低,以波V的稳定性最好,波I消失最快,各波潜伏期均延长,标准差增大,各波间期缩短。在同一刺激声强下,随着月龄的增长,波I潜伏期无明显变化,波III、V潜伏期和I—III、III—V、I—V波间期均有明显缩短。在4月龄前波III、V潜伏期和I—III、III—V、I—V波间期各月龄组间差异均有统计学意义（P〈0．05）,4月龄后各月龄组间的差异无统计学意义（P〉0．05）。结论本组1～6月龄正常婴儿短声诱发听性脑干反应反应阈的正常值为16．18±5．35dBnHL;下丘以下听觉神经传导径路在出生后1～4月有较快的发育过程。     

听神经病患者80Hz听觉稳态诱发电位研究

目的:探讨听神经病患者80 Hz听觉稳态诱发电位的特点及与听性脑干诱发电位V波的相关性.方法:以1000 Hz短音95 dBnHL作声刺激,比较听神经病组和正常对照组80 Hz听觉稳态诱发电位及短音听性脑干反应(ABR)的波形差异.结果:听神经病组两种听觉诱发电位波形的同时引出率为85.4%且波幅低或极低,ABR的Ⅰ、Ⅲ波消失;14.6%两种听觉诱发电位波形同时消失.而正常对照组两种波形的同时引出率为100.0%.结论:80 Hz听觉稳态诱发电位与听性脑干反应的V波有明显相关性.     

脑干听觉诱发电位对脑外伤后持续植物状态评价的意义

目的：通过脑干听觉诱发电位（brainstem auditory evoked potential, BAEP）评估颅脑外伤后持续植物状态（persistent vegetative state, PVS）患者的脑干功能。方法：对25例（50耳）PVS患者行BAEP检测，并与对照组行单因素方差分析。结果：PVS患者的BAEP异常率为80%。其改变复杂多样，主要表现为Ⅰ V各波的异常或分化不良，甚至波形缺如；Ⅰ、Ⅲ、Ⅴ波潜伏期（peak latency, PL）延长，I V波间潜伏期（Interpeak latency, IPL）延长，双侧V波潜伏期的耳间差（inter aural latency difference, ILD）增大；Ⅲ V与Ⅰ Ⅲ波IPL之比大于1。结论：PVS患者的BAEP结果呈多样性改变，反映了患者植物状态下存在不同程度的脑干损害，为其诊疗及预后判断提供了可靠的依据。     

Auditory brainstem response differences in diabetic and non-diabetic veterans

A number of studies have found statistically significant delays in auditory brainstem latencies of patients with diabetes compared with non-diabetic controls. However, the mechanisms ascribed as responsible for the latency differences between diabetic and non-diabetic patients vary among studies, and the latency differences, while significant, are small. In this 5-year prospective study, auditory brainstem response testing was conducted with 416 non-diabetic and 375 diabetic veterans from the Portland Veterans Affairs Medical Center as part of a larger study. Patients with diabetes had significantly delayed latencies of Wave III and V in the right ear and significantly prolonged interpeak I-III and I-V latencies in both ears. Stimulus polarity difference yielded slightly different results. None of the diabetes-related clinical characteristics were associated with the latency differences between the subject groups after accounting for hearing loss and age. Effect size was calculated and clinical significance of these differences is discussed.     

Brainstem auditory evoked potentials after irradiation of nasopharyngeal carcinoma--report on two cases with myelopathy of the brainstem

Brainstem auditory evoked potentials (BAEP) were recorded in two patients with nasopharyngeal carcinoma (NPC) irradiated 14 and three years ago respectively and compared with 15 healthy controls. The patients had features of post-irradiation myelopathy of the brainstem with reduced gag reflex, unilateral vocal cord paralysis and fasciculation of the tongue. The first patient had a blind left eye. The second patient had quadriparesis. All ears revealed post-irradiation otitis media changes and mixed deafness. BAEP was not recognizable in the left ear of the first patient and was normal in the left ear of the second patient. Simultaneous electrocochleogram and BAEP were recorded from the right ear of the first case. The wave I-V latency interval were prolonged in both right ears. In the absence of local recurrence and brain secondaries, these BAEP changes are attributed to the post-irradiation myelopathy of brainstem.     

Auditory brainstem activity in children with 9-30 months of bilateral cochlear implant use

Bilateral cochlear implants aim to restore binaural processing along the auditory pathways in children with bilateral deafness. We assessed auditory brainstem activity evoked by single biphasic pulses delivered by an apical or basal electrode from the left, right and both cochlear implants in 13 children. Repeated measures were made over the first 9-30 months of bilateral implant use. In children with short or long periods of unilateral implant use prior to the second implantation, Wave eV of the auditory brainstem response was initially prolonged when evoked by the na?ve versus experienced side. These differences tended to resolve in children first implanted <3 years of age but not in children implanted at older ages with long delays between implants. Latency differences were projected to persist for longer periods in children with long delays between implants compared with children with short delays. No differences in right versus left evoked eV latency were found in 2 children receiving bilateral implants simultaneously and their response latencies decreased over time. Binaural interaction responses showed effects of stimulating electrode position (responses were more detectable when evoked by an apical than basal pair of implant electrodes), and duration of delay between implants (measured by latency delays). The trends shown here suggest a negative impact of unilateral implant use on bilateral auditory brainstem plasticity.     

Asymmetric brain stem auditory evoked responses in infants treated with extracorporeal membrane oxygenation

Brain stem auditory evoked responses (BAERs) were obtained in 25 infants who received extracorporeal membrane oxygenation (ECMO) for severe respiratory failure. Tracings were obtained by means of a Nicolet CA-2000 averager, using a conventional paradigm. The presence or absence of replicated responses at 35 and 75 dB nHL were recorded for each ear. Interpeak latencies I-III, III-V, and I-V were measured and differences between right and left ears were compared, using a matched pair t-test. Wave III-V latencies were longer on the left than right (p less than 0.05), but no significant right-left differences for latencies I-III were noted. Sixteen percent of the infants failed hearing sensitivity criteria, 45% (10/23) had prolonged I-V latencies. At follow-up (age 4 to 12 months) 6/10 infants with prolonged I-V latencies had additional neurologic abnormalities. In this population left ear III-V latencies are prolonged versus right, and the incidence of abnormal BAERs is high. Relative prolongation of left ear III-V latencies (generated from the right brain stem) may be result of right carotid artery and/or jugular vein ligation for ECMO, and abnormal I-V latencies prognosticate future neurologic abnormalities in this population.     

Auditory-evoked brainstem potentials and stapedius muscle reflex: intersubject variability

Like other workers, we found gender differences in auditory-evoked brainstem response latencies. For the time being, this intersubject variability remains unexplained. This difference was observed only for wave V latency, and delta I-V is longer in men than in women, whereas delta I-III is identical. The absence of functional differences in the lower portion of the auditory tract is confirmed by both auditory-evoked brainstem potentials and stapedius reflex latency. Wave V latency and the influence of technical and anatomical factors are discussed as well.     

Electrophysiological measures of auditory function in the neurofilament-deficient mutant quail (Quv)

Auditory pathway electrophysiological studies were performed on the mutant quail 'Quv'. This mutation is known to result in neurofilament deficiencies of both the peripheral and central nervous systems. Auditory evoked brainstem responses (ABRs), electrocochleograms (EcochGs) and middle latency responses (MLRs) were evaluated. ABRs in Quv quails demonstrated markedly altered waveforms exhibiting longer latencies, absence of the later peaks and lower amplitudes. The EcochG showed normal cochlear microphonics with no obvious abnormalities in amplitude or latency and normal latencies for peak N1. Quv quails had a mild threshold elevation with a normal latency for the first peak of the ABR (P1). The Quv MLRs showed no significant differences in amplitude but they revealed a latency prolongation for peaks N0, Pa and Na relative to the controls. We have discovered abnormal findings of auditory evoked potentials in the neurofilament-deficient quail (Quv). We suggest that the smaller axonal size and axonal hypotrophy due to altered neurofilament expression underlies these abnormal auditory evoked potential responses.     

obstructive sleep apnea-hypopnea syndrome and hearing in children

Objective To explore the relationship between hypoxemia and hearing in children with obstructive sleep apnea-hypopnea syndrome. Methods Auditory brainstem responses (ABRs) were recorded in 68 ears and distortion product otoacoustic emissions (DPOAEs) in 60 ears in children with OSAHS and type "A" tympanograms, and in 30 ears in normal children. Results ABR latencies of waves Ⅰ, Ⅲ and Ⅴ, and Ⅰ-Ⅲ, Ⅲ-Ⅴ and Ⅰ-Ⅴ intervals were not statistically different between OSAHS and normal children. Wave Ⅰlatency was delayed in children with OSAHS compared to normal children3 (P<0.05). DPOAE amplitudes in children with mild OSAHS were lower than normal children at 8 kHz (P<0.05). DPOAEs were lower at 6 kHz and 8 kHz in children with moderate/severe OSAHS than normal children (P<0.05). Conclusion Cochlear function was affected when AHI was at or greater than lO/hour. ABR and DPOAE can be used to detect early changes in auditory function in children with OSAHS.     

Brainstem auditory evoked potentials with speech stimulus in neonates

IntroductionBrainstem auditory evoked potentials in response to complex sounds, such as speech sounds, investigate the neural representation of these sounds at subcortical levels, and faithfully reflect the stimulus characteristics. However, there are few studies that utilize this type of stimulus; for it to be used in clinical practice it is necessary to establish standards of normality through studies performed in different populations.ObjectiveTo analyze the latencies and amplitudes of the waves obtained from the tracings of brainstem auditory evoked potentials using speech stimuli in Brazilian neonates with normal hearing and without auditory risk factors.Methods21 neonates with a mean age of 9 days without risk of hearing loss and with normal results at the neonatal hearing screening were evaluated according to the Joint Committee on Infant Hearing protocols. Auditory evoked potentials were performed with speech stimuli (/da/ syllable) at the intensity of 80 dBNA and the latency and amplitude of the waves obtained were analyzed.ResultsIn the transient portion, we observed a 100% response rate for all analyzable waves (Wave I, Wave III, Wave V and Wave A), and these waves exhibited a latency <10 ms. In the sustained portion, Wave B was identified in 53.12% of subjects; Wave C in 75%; Wave D in 90.62%; Wave E in 96.87%; Wave F in 87.5% and Wave O was identified in 87.5% of subjects. The observed latency of these waves ranged from 11.51 ms to 52.16 ms. Greater similarity was observed for the response latencies, as well as greater amplitude variation in the studied group.ConclusionsAlthough the wave morphology obtained for brainstem evoked potentials with speech stimulation in neonates is quite similar to that of adults, a longer latency and greater variation in amplitude were observed in the waves analyzed.     

Lateral asymmetry in the ABR of neonates: evidence and mechanisms

Lateralized processing of auditory stimuli occurs at the level of the auditory cortex but differences in function between the left and right sides are not clear at lower levels of the auditory system. The current study is designed to (1) investigate asymmetric auditory function at the ear and brainstem in human infants and (2) investigate possible mechanisms for asymmetry at these levels. Study 1 evaluated auditory brainstem responses (ABRs) in response to high and low-level clicks presented to the right and left ears of neonates. Wave V was significantly larger in amplitude and waves III and V were shorter in latency when the ABR was generated in the right ear. Study 2 investigated two possible mechanisms of such asymmetry by (a) using contralateral white noise masking to activate the medial olivocochlear system and (b) increasing stimulus rate to reveal neural conduction and synaptic mechanisms. ABR wave V, evoked by clicks to the left ear, showed a greater reduction in amplitude with contralateral noise than the response evoked from the right ear. No systematic asymmetries in ABR latencies or amplitudes were found with increased stimulus rate. We conclude that (1) the click-evoked ABR in neonates demonstrates asymmetric auditory function with a small but significant right ear advantage and (2) asymmetric activation of the medial olivocochlear system, specifically greater contralateral suppression of ABR produced by the left ear, is a possible mechanism for asymmetry.     

Abnormal Cochlear Potentials from Deaf Patients with Mutations in the Otoferlin Gene

Otoferlin is involved in neurotransmitter release at the synapse between inner hair cells (IHCs) and auditory nerve fibres, and mutations in the OTOF gene result in severe to profound hearing loss. Abnormal sound-evoked cochlear potentials were recorded with transtympanic electrocochleography from four children with otoferlin (OTOF) mutations to evaluate physiological effects in humans of abnormal neurotransmitter release from IHCs. The subjects were profoundly deaf with absent auditory brainstem responses and preserved otoacoustic emissions consistent with auditory neuropathy. Two children were compound heterozygotes for mutations c.2732_2735dupAGCT and p.Ala964Glu; one subject was homozygous for mutation p.Phe1795Cys, and one was compound heterozygote for two novel mutations c.1609delG in exon 16 and c.1966delC in exon 18. Cochlear potentials evoked by clicks from 60 to 120 dB peak equivalent sound pressure level were compared to recordings obtained from 16 normally hearing children. Cochlear microphonic (CM) was recorded with normal amplitudes from all but one ear. After cancelling CM, cochlear potentials were of negative polarity with reduced amplitude and prolonged duration compared to controls. These cochlear potentials were recorded as low as 50–90 dB below behavioural thresholds in contrast to the close correlation in controls between cochlear potentials and behavioural threshold. Summating potential was identified in five out of eight ears with normal latency whilst auditory nerve compound action potentials were either absent or of low amplitude. Stimulation at high rates reduced amplitude and duration of the prolonged potentials, consistent with neural generation. This study suggests that mechano-electrical transduction and cochlear amplification are normal in patients with OTOF mutations. The low-amplitude prolonged negative potentials are consistent with decreased neurotransmitter release resulting in abnormal dendritic activation and impairment of auditory nerve firing.