An Acoustically Evoked Short Latency Negative Response in Profound Hearing Loss Patients

In our auditory brainstem response (ABR) tests, a peculiar V-shaped negative wave at around 3-4 ms latency was observed. At present, this acoustically evoked short latency negative response (ASNR) is poorly understood. In order to study its appearance and origin, the ABR data of 3104 tests during 1980-98 were reviewed. The ASNR was found only in profound hearing loss ears under intense stimuli (80-120 dB nHL). Out of the total 653 profound hearing loss patients (981 ears), the click-evoked ASNRs were present in 80 patients (12.3%), 117 ears (11.9%). The age range was from 8 months to 70 years. Demographic outcome revealed significant higher appearance rates in young subjects especially in the 20-30 years group. The ASNR was excluded from an artifact by its reproducibility over time, equipment and institutes. Moreover, it became absent after external auditory canal occlusion, which simply blocked the air conduction without any influence upon scalp potentials or equipment. It had neural response characteristics that the latency and amplitude shortened and increased respectively in response to the increase of stimulus intensity. Because the peculiar V-shaped waveform obviously differs from ABR, the ASNR was not interpreted as a potential generated from the conventional auditory pathway. On the other hand, the ASNR individuals were of good vestibular function in sharp contrast with their poor hearing. This suggests the probable relation between the ASNR and the vestibular system. The saccule and vestibular nucleus are hypothesized to be the sense organ and the origin of the response respectively.     

人类声诱发短潜伏期负电位的研究

目的在极重度感音性聋耳的ABR检测中发现一个位于3～4ms潜伏期的"V"字形负向波形,称声诱发短潜伏期负电位(Acoustically Evoked Short Latency Negative Response,ASNR)。本研究通过大宗病例调查和临床实验来探讨ASNR的特点和起源。方法回顾性调查并分析3104例ABR检测结果,以详尽了解ASNR的出现率和特性。对20名双耳极重度感音性耳聋患者(6～62岁)和12名健康人(23～30岁)进行了ABR和前庭诱发肌源性电位(VEMP)测试。患者组包括了16名人工耳蜗植入术后的患者,植入耳在裸耳状态时可提供无功能耳蜗模型。结果判读侧重于:人工耳蜗植入耳能否诱发ASNR,以及对比在极重度感音性聋耳中ASNR组和非ASNR组的VEMP出现率及反应阈值。结果ASNR仅出现于极重度感音性聋耳,并且对强声刺激(80～120dBnHL)有依赖性。在653例极重度感音性聋患者(981耳)的ABR波形中,有80例(12.3%)117耳(11.9%)出现了ASNR。ASNR有良好的重复性,可排除伪迹干扰的可能性。ASNR具有神经电位的特征,表现在随着声刺激的增强,其潜伏期缩短而振幅增大。ASNR与ABR的波形完全不一样,无法将其解释为传统听觉神经通路产生的电位。临床实验中,3个人工耳蜗植入耳能诱发出ASNR,说明ASNR的发生与耳蜗无关。所有9个ASNR耳都诱发出VEMP,且阈值与正常对照组无统计学差异(P>0.05),提示ASNR耳具有正常的球囊功能。在非ASNR组中,三分之二没有引出VEMP,而另外三分之一虽然可以诱发出VEMP,但阈值明显较正常对照组高(P<0.01),分别提示球囊功能丧失或低下。此外,有一外半规管麻痹耳诱发出了ASNR和VEMP。结论ASNR并非伪迹,而是一种依赖强声刺激,且只出现于极重度感音性聋耳的神经电位。ASNR的出现完全依赖于正常的球囊功能,而不依赖于残余听力或者半规管功能。据此认为ASNR起源感觉器官为球囊,根据其潜伏期推测电位源自前庭神经核。     

短纯音诱发的听性脑干反应测试中声诱发短潜伏期负反应研究

目的 总结在有听力损失儿童中行短纯音诱发的听性脑干反应(tbABR)测试时记录到的声诱发短潜伏期负反应(acoustically short latency negative response,ASNR)的特点.方法 在有听力损失的0～6岁儿童中应用SmartEP听觉诱发电位仪记录短声和短纯音ABR的反应阈,在记录到ASNR的受试者中分析其反应阈和潜伏期.结果 在所有80受试耳中共7耳(8.75%)在cABR测试中引出ASNR,40耳(50%)在tbABR测试中引出ASNR,其中1 kHz引出率最高(37耳,46.25%),2 kHz次之(25耳,31.25%).引出ASNR者ABR波V反应阈最低65 dB nHL,ASNR反应阈最低80 dB nHL.0.5、1、2和4 kHz短纯音诱发的ASNR潜伏期分别为6～8、5～7、3～5、3～4 ms.随刺激强度的增加,其潜伏期缩短.结论 有听力损失的儿童tbABR测试中可以记录到AS-NR,但不影响以波V反应阈评估听力.     

极重度听损大前庭水管综合征婴幼儿患者ABR和ASSR结果分析

目的通过对极重度听力损失的大前庭水管综合征婴幼儿进行听性脑干反应（ABR）和多频稳态反应（ASSR）测试,探讨其ABR检查过程中出现的声诱发短潜伏期负向波（acoustically evoked short latency negative response,ASNR）及其ASSR特点。方法回顾性研究22例（42耳）极重度听力损失的大前庭水管综合征（LVAS）婴幼儿,另选择28例（56耳）极重度听力损失的非LVAS的感音神经性耳聋婴幼儿作为对照组,研究其ABR及ASSR相关性。结果①LVAS婴幼儿组ABR测试中,36耳（85．7％）记录到AsNR,在109．6 dB nHL刺激强度引出的ASNR平均潜伏期在3．04±0．22msT对照组中婴幼儿无一例记录到ASNR。②LVAS婴幼儿组ASSRNI]试在250、500和1000Hz引出率明显高于对照组,两组间差异有统计学意义（P〈0．01）。结论相比于普通的极重度感音神经性耳聋患儿,极重度听损LVAS患儿进行听力学检查时,ABR容易出现ASNR负向波,ASSR测试结果显示较高的中低频的电位反应引出率,此结果可用于临床辅助诊断大前庭水管综合征。     

豚鼠声诱发短潜伏期负电位的来源初探

目的 建立声诱发短潜伏期负电位(acoustically evoked short latency negative response,ASNR)豚鼠模型,即重度感音性聋但球囊功能正常的豚鼠,用短声刺激诱发ASNR,并通过冷热试验及前庭诱发肌源性电位(vestibular evoked myogenic potential,VEMP)来验证豚鼠的前庭功能.方法 将32只健康豚鼠按随机数字表法分为两组,对照组16只(32耳)、药物致聋组16只(32耳).致聋组经给药(硫酸卡那霉素+利尿酸)致聋,7～10 d后对所有动物进行听觉前庭功能检查,包括听性脑干反应(ABR)、VEMP及冷热试验.致聋组豚鼠根据ASNR的引出情况分为ASNR引出组及ASNR未引出组.结果 致聋组有11只动物(22耳)完成测试,其中8耳引出ASNR(36.4%),阈值为120～130 dB SPL,平均(124.4±5.0)dB SPL,潜伏期l.75～2.60 ms,平均(2.15±0.27)ms,阈值平均潜伏期(2.34±0.18)ms.ASNR引出组8耳皆引出VEMP,其阈值及正负峰潜伏期与对照组比较,差异均无统计学意义(P值均＞0.05);ASNR未引出组中有4耳引出VEMP,其阈值及正负峰潜伏期与对照组比较差异亦无统计学意义(P值均＞0.05).ASNR引出组和未引出组VEMP引出率比较,差异具有统计学意义(P=0.002).致聋组VEMP、ASNR的引出情况与冷热试验的眼震结果之间均无相关关系(P值均＞0.05).结论 ASNR与反映球囊功能的VEMP具有一致性,而与代表半规管功能的冷热试验眼震结果无关,ASNR与VESP可能同起源于球囊.

Abstract：

Objective To establish a model of acoustically evoked short latency negative response (ASNR) in guinea pigs, a model of profound hearing loss with normal saccular functions, and verify the correlation between ASNR and vestibular evoked myogenic potential (VEMP). Methods Thirty-two healthy guinea pigs were employed in the experiment, which were randomly divided into control group ( 16subjects) and deafened group (16 subjects). Each animal experienced auditory and vestibular tests including auditory brainstem response ( ABR), VEMP and caloric test. A quick treatment was employed for deafened group consisting of a subcutaneous injection of kanamycin at a dose of 400 mg/kg followed by a jugular vein injection of ethacrynic acid at a dose of 40 mg/kg one hour later. The animals were received ABR, VEMP and caloric test 7 - 10 days following the drug administration. The deafened group was further divided into ASNR group and non-ASNR group, based on the presence of ASNR. Results In deafened group, five subjects died postoperatively, 11 subjects (22 ears) provided full data, ASNR was elicited in eight ears (36.4%), the threshold was 120- 130 dB SPL with mean of (124.4 ±4.96) dB SPL. Its latency range was 1.75 - 2. 60 ms with mean of ( 2. 15 ± 0. 27 ) ms. The mean latency of threshold was (2. 34 ±0. 18) ms. All eight ASNR ears presented with VEMP. The VEMP threshold, positive and negative potential latencies proved no statistical difference (P ＞ 0. 05 ) between ASNR group and control group.Significant difference was detected between the VEMP presence of ASNR group and non-ASNR group ( P =0. 002). There was no statistically significant correlation between VEMP and caloric test neither between ASNR and caloric test in deafened group. Conclusions This study evoked ASNR in an ototoxicity guinea pig model which has profound hearing loss with normal saccular functions. The presence of ASNR correlated with VEMP, however, not correlated with caloric test, suggesting that ASNR and VEMP are both originated from the saccule.     

An acoustically evoked short latency negative response in profound hearing loss infants

OBJECTIVE: A large negative deflection with a 3-4 ms latency within the auditory brainstem response has been reported in some profound hearing loss ears under intense stimuli in adult subjects. The wave has been termed the N3 potential or acoustically evoked short latency negative response and it is assumed to be a vestibular-evoked potential. The purpose of the current study was to investigate the relationship between the vestibular-evoked myogenic potentials and the acoustically evoked short latency negative response in infants with a functionless cochlea and normal or impaired semicircular canal. METHODS: Seventeen 3 months old infants with profound bilateral sensorineural hearing loss had acoustically evoked short latency negative responses and vestibular-evoked myogenic potentials recorded and caloric tests performed. RESULTS: No spontaneous symptoms of vestibular dysfunction were found in the examined infants. ASNR with medium latency 3.3 ms and threshold value 80-90 dB normal hearing level was elicited from 10 ears. VEMPs were present in 12 ears. ASNRs and VEMPs were absent in two ears with normal response to caloric stimulation. No response to caloric stimulation was elicited from other two ears with normal saccular function. For the ears with absence of ASNR, four had normal VEMP and the rest were considered to have saccular afunction. Significant correlation was found between the presence of ASNRs and VEMPs. CONCLUSION: Acoustically evoked short latency negative responses could be a valuable tool for assessing vestibular function in infants with profound sensorineural hearing loss.     

The effect of saccular function on static balance ability of profound hearing-impaired children

Objective

Researches have shown that in clinical practice, balance disorders in children with congenital or early acquired severe to profound hearing loss are probable. The purposes of present study were to specify the percentage of vestibular evoked myogenic potential (VEMP) and an acoustically evoked, short latency negative response (ASNR) recordings and the relation between their presence and static balance ability and postural control of children with profound sensorineural hearing loss (SNHL).

Methods

Thirty children with profound SNHL, with an average age of 6.93 years, underwent the VEMP and auditory brainstem response (ABR) tests. Both VEMP and ABR were recorded at the threshold level through air-conduction stimulation via an insert receiver. The static balance performance of the hearing-impaired children was tested with six exercises and compared with that of 30 age- and sex-matched normal-hearing children as controls.

Results

VEMP was recorded in 53.3% of ears and ASNR in 40.0%. VEMP was revealed in all ears with ASNR, and a significant correlation was shown between their presence (p = 0.005) and also between the ASNR wave latency and P1 (p = 0.0001) and N1 (p = 0.004) wave amplitude of VEMP. There was a significant correlation between the presence of VEMP and ASNR with the performance of the children in two static balance skills, namely standing on one leg with eyes open on a line and the same practice on the balance beam (p ≤ 0.008).

Conclusion

There was a close relation between the presence of VEMP and ASNR. Additionally, when ASNR was present, the recording of VEMP could be expected. Successful performance in the static balance exercises with reduced vestibular and somatosensory inputs increased the possibility of the recording of ASNR and VEMP.     

Prognostic factors for hearing preservation in vestibular schwannoma surgery

OBJECTIVE: To determine whether prognostic indicators for hearing preservation could be identified in patients with vestibular schwannoma undergoing middle fossa craniotomy resection. STUDY DESIGN: Prospective case review. SETTING: Private practice tertiary referral center. PATIENTS: 333 patients with serviceable hearing and vestibular schwannoma resected by middle fossa craniotomy from 1992 to 1998. MAIN OUTCOME MEASURES: Potential prognostic indicators, including tumor size and nerve of origin, preoperative pure-tone average, speech discrimination, distortion product otoacoustic emission testing, age, auditory brainstem response (ABR), and electronystagmography. RESULTS: Postoperative hearing near preoperative levels was attained in 167 patients (50%), with an American Academy of Otolaryngology-Head and Neck Surgery Class A hearing result in 33% and a Class B result in 26%. Comparison of potential prognostic indicators between groups with hearing preserved and the group with no measurable hearing revealed significant differences in preoperative hearing, ABR, and tumor origin data. Better preoperative hearing, shorter intraaural wave V latency, shorter absolute wave V latency, and superior vestibular nerve origin were associated with higher rates of hearing preservation. CONCLUSIONS: Preoperative hearing status, ABR, and intraoperative tumor origin data were shown to be of value as prognostic indicators.     

听神经瘤致聋机理——14例(16耳)听神经瘤病人听力测试结果分析

目的 :探讨听神经瘤听力损失的病理生理机制。方法 :对 14例 (16耳 )听神经瘤患者行纯音听阈、阻抗、听性脑干反应 (ABR)、诱发耳声发射测试 (EOAE)及 CT和 (或 ) MRI扫描。 EOAE能引出的 4耳还检测其传出抑制功能 ,ABR不能检测且 EOAE不能引出的重度聋 (听力损失大于 80 d B)有 5耳行鼓岬刺激试验 (PST)。结果 :16耳听神经瘤中2耳 (12 .5 0 % )听力损失源于神经性损害 ;6耳 (37.5 0 % )蜗性损害 ;8耳 (5 0 % )蜗 -神经性损害。能引出 EOAE的 4耳均有传出功能障碍。结论 :EOAE可评价听神经瘤的耳蜗功能状态 ;ABR结合 PST能分析听神经瘤的蜗后神经功能。听神经瘤的听觉病理可同时或单独发生于听外周的耳蜗水平、第 对颅神经 (传入神经 )水平和橄榄核耳蜗传出神经水平。     

婴儿多种客观听力检测方法的综合评估

目的探讨多种客观听力检测方法在婴儿听力评估中的应用。方法采用听性脑干反应、40Hz听觉相关电位或听觉稳态反应、畸变产物耳声发射及鼓室声导抗等方法,对初筛和复筛未通过的200例（400例）婴儿进行了听力测试,并对测试结果进行对比分析。结果400耳中各项结果均正常77耳（19．25％）,一项或一项以上检查异常323耳（80．75％）。检查异常的323耳中传导性听力损失59耳（18．27％）,感音神经性听力损失172耳（53．25％）,混合性听力损失92耳（28．48％）。接受听性脑干反应测试的400耳中。正常199耳（49．75％）,异常201耳（50．25％）。以听性脑干反应阈值评估听力损失程度。轻度96耳（47．76％）,中度29耳（14．43％）,重度22耳（10．95％）,极重度54耳（26．86％）。接受40Hz听觉相关电位测试的184耳中,正常52耳（28．26％）,异常132耳（71．74％）。以40Hz听觉相关电位反应阈值评估听力损失程度,轻度68耳（51．51％）,中度34耳（25．76％）,重度14耳（10．61％）,极重度16耳（12．12％）。接受听觉稳态反应测试的216耳中,正常62耳（28．70％）,异常154．1~-（71．30％）。接受畸变产物耳声发射测试的400耳中,正常114耳（28．50％）,异常286耳（71．50％）。接受鼓室声导抗测试的400耳中,正常310耳（77．50％）,异常90耳（22．50％）。结论多种客观听力检测方法的联合运用,对判断婴儿听力损失的程度和性质有一定帮助,可为早期干预提供依据。     

听性脑干反应联合听觉多频稳态诱发反应在儿童听力筛查和诊断中的应用

目的利用听觉稳态诱发反应（auditory steady state evoked response,ASSER）联合听性脑干反应（auditory brainstem response,ABR）测试对婴幼儿进行听力检测,评价两种方法对婴幼儿听力损伤早期发现及损失程度评估的作用。方法对7 6例（1 5 2耳）畸变产物耳声发射（distortion product otoacoustic emission,DPOAE）复筛未通过的婴幼儿及门诊就诊疑有听力损失的婴幼儿进行ASSER和ABR测试,对结果进行比较。结果7 6例（1 5 2耳）婴幼儿ABR反应阈与ASSER高频反应阈比较,差异无统计学意义（P＆lt;0.0 5）。ABR在最大输出无反应而ASSER测试中各频率能引出反应。结论ASSER联合ABR检查可以更全面的评估婴幼儿的真实听力情况,对ABR无反应的患儿还应进行ASSER测试,有助于全面评估其听力损失程度。     

Sound-evoked myogenic potentials and responses with 3-ms latency in auditory brainstem response.

OBJECTIVES: The vestibular-evoked myogenic potential (VEMP) has shed new light on vestibular testing. A large negative deflection with a 3-ms latency within the auditory brainstem response (ABR) has been reported in some patients with deafness. This negative deflection has been termed the N3 potential and it is assumed to be a vestibular-evoked potential. This study investigated the relationship between the VEMP and the N3 potential. STUDY DESIGN: Prospective evaluation of the VEMP and the N3 potential in 21 patients. METHODS: The oto-neurological tests, including caloric test, hearing sensitivity test, VEMP, and ABR, were performed and data were analyzed. RESULTS: The average hearing threshold ranged from 65 to above 110 dB, which includes 9 (37.5%) totally deaf ears. The N3 potentials were recorded in 10 (41.7%) ears. A normal VEMP was detected in 16 (66.7%) ears. Canal paresis was observed in 11 (45.8%) ears. CONCLUSIONS: Both the VEMP and the N3 potential appear to originate from the sacculus, but because the characteristics of these two responses are not identical, additional factors might be involved in the generation of the N3 potential.     

Vestibular system in infants with hereditary nonsyndromic deafness.

OBJECTIVE: Seventy percent of genetic deafness occurs without associated phenotypic characteristics and is termed nonsyndromic hereditary hearing impairment, analyzed by numerous genetic loci. Many forms of nonsyndromic hereditary hearing impairment are secondary to diverse cochleosaccular dysfunctions. The purpose of the present study was to evaluate vestibular function in a group of infants with hereditary nonsyndromic deafness using caloric tests and vestibular evoked myogenic potentials. PATIENTS: Fifty-eight infants aged 3 months: 40 healthy controls and 18 infants with hereditary nonsyndromic deafness. Infants with other risk factors of inner ear damage were excluded. INTERVENTION: Diagnostic. Vestibular evoked myogenic potentials and auditory brainstem responses were recorded, and caloric tests were performed. MAIN OUTCOME MEASURES: The vestibular function was impaired in 14 patients. RESULTS: The results of all the tests in the controls were normal. In the patients, no reaction to caloric stimulation was elicited from 12 examined ears, and no vestibular evoked myogenic potentials were recorded from 24 ears. Caloric responses elicited from 12 ears were weakened. Hearing thresholds were in the interval 40- to 80-dB hearing level in 20 ears and more than 80-dB hearing level in 16 ears. The presence of caloric responses correlated with the hearing threshold interval. CONCLUSION: In the group of infants with hereditary nonsyndromic deafness, the degree of the semicircular canal impairment is higher in individuals with profound hearing loss. Vestibular evoked myogenic potentials are more frequently absent than caloric responses. The vestibular organ should be routinely examined in infants with hereditary nonsyndromic deafness.     

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.     

Mechanisms in noise-induced permanent hearing loss: an evoked otoacoustic emission and auditory brainstem response study

In this study 22 patients (44 ears) with noise-induced permanent hearing loss were audiologically evaluated using transient-evoked otoacoustic emissions (TEOAE) and auditory brain-stem response (ABR). Twenty-one normal subjects (42 ears) without exposure to occupational noise were used as controls. Based upon the hearing loss at 4, 3, 2 and 1 kHz on the pure-tone audiogram, they were classified into four groups. In group 1 (eight ears), emissions were present in all ears but their TEOAE-noise level and their reproducibility (percentage) proved to be weak. The auditory brain-stem response (ABR) indicated that the I/V amplitude ratio, the latency values of wave V and the I-V intervals fell within the normal range in all ears. In Group 2 (14 ears), 40 per cent had no emissions, whereas the remaining ears showed weak emissions. The ABR revealed that in all ears the I/V amplitude ratio became small while wave V peak latency as well as I-V intervals were within the normal range. In Group 3 (10 ears), emissions were absent in 50 per cent, while in the other ears the emissions were very weak. The ABR revealed that the I/V amplitude ratio, which could be calculated in the 60 per cent in which wave I was present, was smaller than in Group 2. Wave V latency as well as I-V intervals were within the normal range. In Group 4 (12 ears), none of the ears showed emissions. The ABR indicated that the I/V amplitude ratio was much smaller when wave I was present (27 per cent) as well as I-V interval values being within the normal range. Wave V absolute latency value (delta V index) indicated a positive index in 17 per cent of this group (two ears) when wave I was absent. In the present study a dynamic process from cochlear outer hair cells to cochlear neurons was seen, correlating with an increasing hearing loss.     

Auditory brainstem responses in noise-induced permanent hearing loss

Fifty-four patients (108 ears) with presumed noise-induced hearing loss, were subjected to tonal and speech audiometry, impedance tests and measurements of auditory brainstem responses (ABR), in order to check for possible retrocochlear involvement. ABR data indicated that latency values of waves I, III and V, as well as III-I, V-III and V-I intervals fell within the normal range in all cases (M +/- 2 SD), even for fast repetition rates (51 stim/s). Poor waveform resolution of early components, particularly of wave I, was found in 12 ears (11.1%) and a total absence of evoked potentials not always related to the hearing loss, occurred in 5 ears (4.6%).     

单侧听神经病附三例报告

目的　探讨单侧听神经病的听功能特征及病损部位。方法　报告及分析 3例患者的临床资料、纯音测听、声导抗测试、畸变产物耳声发射 (DPOAE)、听性脑干反应 (ABR)检测结果。结果　 3例单侧患耳纯音听力图分别为上升型、平坦型及下降型 ,听力损失 1例为中度 ,2例为重度 ,另侧听力图正常 ;3例患者双侧DPOAE正常引出 ,而ABR患侧未能引出 ,健侧正常引出。颞骨HRCT未见异常。结论　单侧听神经病的听功能特征与双侧听神经病的听功能特征相同。诱发性耳声发射及ABR对鉴别一般感音神经性聋与中枢性聋有重要意义。病损部位可能在内毛细胞至听神经的传入通路     

Auditory sensitivity in children using the auditory steady-state response

OBJECTIVE: To determine the effectiveness of auditory steady-state response (ASSR) as a measure of hearing sensitivity in young children suspect for significant hearing loss. DESIGN: Within-subject comparisons of click auditory brainstem response (ABR) thresholds and ASSR thresholds. SUBJECTS: The study population comprised 42 children suspect for hearing loss and subsequently referred for hearing assessment using electrophysiologic techniques. MAIN OUTCOME MEASURES: Electrophysiologic threshold responses for click ABR and ASSR stimuli (0.5, 1, 2, and 4 kHz) for right and left ears. RESULTS: Based on ABR and ASSR thresholds, 50% of the subjects demonstrated significant hearing loss in the severe to profound range. In some subjects, ASSRs were present at higher stimulus levels when click ABRs were absent. Significant correlations (P<.05) were found between high-frequency ASSR and click ABR thresholds for this study sample. For some subjects, ASSR findings suggested differences between ears that were not observable from the no-response click ABR results. CONCLUSIONS: Auditory steady-state response testing may provide additional information for children who demonstrate hearing levels in the severe to profound range. This information may be helpful when selecting the ear for cochlear implantation for a young hearing-impaired child. Multiple objective methods, such as ABR and ASSR testing, may be needed to determine accurate hearing sensitivity for young children being considered for sensory devices, and in particular, cochlear implants.     

Prediction of auditory brainstem wave V latency as a diagnostic tool of sensorineural hearing loss

The lesion location (cochlear vs. retrocochlear) of sensorineural hearing loss may be differentiated with a diagnostic index (delta V), which is calculated from the wave V latency of the monaurally evoked auditory brainstem response (ABR), and from the pure-tone hearing threshold at 2 and 4 kHz. The delta V values obtained from 80 recruiting ears have proven to correlate linearly to the amount of the hearing loss, hence allowing to define appropriate confidence boundaries for cochlear hearing losses. In contrast, the delta V values obtained from 32 ears of patients with retrocochlear lesions--cerebellopontine angle (CPA) tumors--were all found to exceed the 95% upper confidence limits projected for cochlear lesions, thus giving a 100% rate of true results in the detection of retrocochlear pathology. These results, providing an ABR parametric model for the cochlear hearing loss, suggest a diagnostic strategy for the early detection of CPA tumors based on the exclusion of a cochlear hearing loss.     

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.