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。     

多频稳态诱发电位单频刺激与多频刺激测试结果的观察比较

目的 研究正常听力青年人多频稳态诱发电位单频刺激与多频刺激所记录到的反应阈,比较在4个测试频率得到的两种反应阈是否有差异。方法　分别对30例听力正常的年轻人进行纯音测听、多频稳态诱发电位多频刺激和单频刺激测试,记录0.5k、1k、2k、4 kHz的测试结果,并对结果进行统计学处理。结果 听力正常青年人多频稳态诱发电位单频刺激与多频刺激的反应阈除0.5kHz处有显著差异(p<0.001)外,1k、2k、4 kHz三个频率均无显著差异,两种刺激方式下得到的反应阈与纯音听阈的差距在15～25dB。结论 多频稳态诱发电位有较好的频率特性,可用来预测纯音听力图,临床应用时在0.5kHz处用单频刺激获得的阈值比多频刺激更接近纯音听阈。     

单频和多频刺激的多频稳态反应比较

目的　了解单频与多频同时刺激方式的多频稳态反应阈值是否有差异。方法　分别对 30例听力正常的青年人进行纯音听阈测试 ,并采用单频和多频同时刺激 ,记录 0 .5、1、2、4kHz四个频率多频稳态反应的测试结果 ,并对结果进行统计学处理。结果　听力正常青年人单频与多频刺激的多频稳态反应阈值除 0 .5kHz处有显著差异 (P <0 .0 0 1)外 ,1、2、4kHz三个频率均无显著差异 (P >0 .0 5 ) ,两种刺激方式下得到的反应阈与纯音听阈的差距均在 15～ 2 5dB。结论　多频稳态反应有较好的频率特性 ,单频刺激与多频刺激两种测试方式所得到的反应阈相近 ,但临床应用时建议在 0 .5kHz处采用单频刺激记录     

正常听力成人骨导听性稳态反应的研究

目的①通过正常听力成人乳突和耳后听性稳态反应（auditory steady--state response,ASSR）测试信号行为阈值的测试,研究骨振器位置与反应阈的关系并建立该信号骨导的正常听力级;②通过单频及多频刺激方式骨导ASSR的反应幅值及阈值的比较,研究刺激方式对骨导ASSR的影响。方法ASSR测试信号为0．5、1、2、4kHz短音（0．5kHz的上升／下降时间为4ms,1、2和4kHz为2ms,无平台）,其重复速率分别为77、87、93、101Hz,经B71骨振器给出。将正常听力成人分为两组,实验1组（30人）,分别记录0．5、1、2、4kHz ASSR测试信号在乳突、耳后的骨导行为阈值;实验2组（12人）,分别采用单、多频刺激方式,记录其0．5、1、2、4kHz的反应阈以及刺激强度为50dBnHL时的反应幅值。结果①骨振器位于乳突与耳后的骨导行为阈值无显著性差异,0．5、1、2、4kHz的骨导行为反应阈分别为62．6&#177;4．8、47．1&#177;4．8、46．8&#177;6．2、32．4&#177;5．1dB re：1μN（ppe）,取该反应阈的均值作为本研究所使用信号的骨导正常听力级,记作0dBnHL;②在刺激强度为50dBnHI。时,不同刺激方式间反应幅值差异有显著统计学意义;③单、多频刺激方式间骨导ASSR阈值差异无统计学意义,0．5、1、2、4kHz阈值分别为96．7&#177;9．7、70．3&#177;11．6、60．6&#177;7．4、52．8&#177;7．2dBr e：1μN（ppe）,各频率间差异有显著统计学意义。结论①骨振器位于乳突与耳后对行为阈值没有显著性影响;②在刺激强度为50dB nHL时,单、多频刺激方式的反应幅值差异有显著统计学意义;③单、多频刺激方式下,骨导ASSR阈值差异无统计学意义。     

正常青年人多频稳态反应阈值的测试

目的 测定正常青年人多频稳态反应（ASSR）阈值，并探讨其与临床实际听阈的差异。方法 选正常青年人56例（112耳）行ASSR阈值测试。结果 在0．5-4．0kHz频率ASSR阈值为26-53d BHL，各频率阈值无明显差异；ASSR阈值与相应纯音听阈间的差值为12-39dB，各频率差值亦无明显差异。结论 正常青年人ASSR阈值与纯音听阈间有一定差值，欲通过测试ASSR阈值推测其听阈则需在ASSR阈值基础上减去此差值。     

听性稳态反应(6)

4.2.4 关于ASSR采用刺激声强度的校准和反应阈强度单位 目前国内有学者用国际标准校准纯音听力零级的标准化方法来校准ASSR用的调制声,这显然存在问题.因为尽管调幅声频率特性很好,与纯音相近,但二者绝对不能等同,ISO颁布的各项标准有严格的限定,绝不能改变测试设备或被校的对象.我们认为用"生理校准"法较为合适,即选择一组听力正常男、女青年(约30～50人),纯音听阈不超过5 dB HL,无耳科疾病史、噪声接触史和耳毒性药物使用史,进行各频率调幅声的主观测听和ASSR反应阈测试,取该组受试者的平均值,计算二者阈值之差,作为修正值,例如500 Hz的调幅声平均主观听阈为5 dB SPL,作为0 dB nHL,而ASSR的反应阈平均值为35 dB SPL,二者之差为30 dB,即ASSR的平均反应阈为30 dB nHL,其它频率以此类推,从而将ASSR机器输出的SPL换算成nHL.     

正常青年人短纯音ABR和ASSR的相关性研究

目的比较正常青年人短纯音听性脑干反应（auditory brainstem response，ABR）和听性稳态反应（auditory steady-state response，ASSR）反应阈的差异及相关性。方法对10名（20耳）听力正常青年人进行短纯音ABR和ASSR反应阈测试，分别记录0．5．1、2和4 kHz的反应阈，比较这两种不同测试方法所得反应阈的特点及相关性。结果短纯音ABR和ASSR反应阈无显著性差异（P〉O．05），两者在0．5、1、2和4 kHz处的相关系数分别为0．49、0．52．0．64和0．76。结论正常青年人短纯音ABR反应阈和ASSR反应阈存在一定的相关性，高频处的相关性较低频好。     

正常青年人多频稳态听觉诱发反应测试

目的 :测定正常青年人多频稳态听觉诱发反应 (ASSR)阈值 ,为临床诊断提供客观依据。方法 :选正常青年人 2 2例 (4 4耳 ) ,行ASSR阈值测试。结果 :在 0 .2 5～ 8.0kHz频区间 ,ASSR平均阈值约在 4 0～ 6 0dBHL之间 ,从低频到高频其阈值越来越高 ,0 .2 5kHz、0 .5kHz、1.0kHz处的ASSR平均阈值约为 4 0dBHL ,2 .0kHz处约为 4 5dBHL ,4 .0kHz处约为 5 0dBHL ,8.0kHz处约为 6 0dBHL。ASSR阈值与纯音听阈间差值多在2 5～ 5 5dBHL之间 ,从低频到高频其阈差值越来越高 ,0 .2 5kHz处的差值约为 2 5dBHL ,0 .5kHz处约30dBHL ,1.0kHz处约 35dBHL ,2 .0kHz处约 4 0dBHL ,4 .0kHz处约 5 0dBHL ,8.0kHz处约 5 5dBHL。结论 :正常青年人ASSR阈值与纯音听阈间有一定差值。利用这一差值 ,通过测试ASSR阈值可推断出被检查者纯音听阈的阈值     

儿童分泌性中耳炎患者骨导听觉稳态诱发反应的测试

目的研究听觉稳态诱发反应(ASSR)对儿童传导性聋及骨导客观听阈评估的准确性。方法对26例(32耳)儿童分泌性中耳炎患者进行气、骨导ASSR及纯音测听,并将ASSR反应阈和纯音听阈进行比较。结果气、骨导ASSR反应阈和纯音听阈之间具有较好的相关性,ASSR气、骨导反应阈均高于纯音气、骨导听阈,ASSR骨导反应阈可以预测相应的纯音骨导听阈。ASSR对儿童传导性聋评估的准确性和纯音测听相似。结论 ASSR可用作儿童传导性聋患者客观听阈的评估。     

多频听觉稳态反应与切迹噪声掩蔽短纯音诱发的听性脑干反应对纯音听阈的预测[论著]

目的　在感音神经性听力损失（sensorineural hearing loss,SNHL）成年患者中通过回归方程,应用多频听觉稳态反应（auditory steady-state response,ASSR）和同 侧切迹噪声（notched noise,NN）掩蔽短纯音诱发的听性脑干反应（NN-ABR）预测纯音听阈。方法　测试22例（30耳）SNHL成年患者的多频ASSR和NN-ABR反应阈,将其代入各自对纯音听阈的回归方程,将所得的预测听阈与实际纯音听阈进行比较。结果　本组SNHL成年患者0.5、1、2、4 kHz的多频ASSR预测听阈与实际纯音听阈之差为（-1.37±10.6）、（-0.47±9.8）、（1.98±6.6）、（-3.8±11.4）dB;相应频率NN-ABR预测听阈与实际纯音听阈之差为（-0.32±9.6）、（1.4±7.9）、（0.18±5.7）、（-0.8±6.0）dB。协方差分析显示测试方法对预测结果无显著影响（F =0.669,P =0.415）。结论　使用多频ASSR和NN-ABR反应阈通过回归方程预测纯音听阈均有较高的准确性。     

Fitting range of the BAHA Cordelle

The performance of the most powerful Bone-Anchored Hearing Aid (BAHA) currently available, the BAHA Cordelle, was evaluated in 25 patients with severe to profound mixed hearing loss. Patients showed bone conduction thresholds at 500, 1000 and 2000 Hz, ranged between 30 and 70 dB HL, and an additional air-bone gap of about at least 30 dB. With the BAHA Cordelle, free-field thresholds improve relative to bone-conduction thresholds with 1.5, 5.0, 17.8, and 4.3 dB at 500, 1000, 2000, and 4000 Hz, respectively, with substantial inter-individual variability. The differences in unaided air conduction thresholds and aided free-field thresholds amount to 45.3, 45.8, 47.5, and 43.5 dB at 500, 1000, 2000, and 4000 Hz, respectively. Speech perception, measured both with monosyllables of the consonant-vowel-consonant type and with bisyllables, showed highly similar results. The fitting range of a (linear) hearing aid is determined by its gain characteristics. Requiring aided speech reception thresholds at or better than 65 dB SPL results in an upper limit of the fitting range of the BAHA Cordelle for bone-conduction thresholds of 51, 56, 67, and 58 dB HL at 500, 1000, 2000, and 4000 Hz, respectively. The dynamic range provided by the BAHA Cordelle was estimated from loudness growth functions at 500, 1500, and 3000 Hz employing 7-point categorical scaling. On average, aided loudness growth functions exhibit normal slopes but they level off at input levels of about 80, 70, 65 dB SPL for 500, 1500, and 3000 Hz stimuli, respectively. Measurements with a skull simulator demonstrated that the levelling-off reflects saturation of the output of the Cordelle. The relatively low saturation levels of the device suggest that increasing maximum output levels may be a worthwhile consideration for candidates with more profound sensorineural loss.     

前额安置B71/B81骨振器手动、自动测听模式阈值比较

目的测定前额安置B71、B81骨导振器时纯音骨导阈值差异。方法征集健听青年志愿者21名(42耳),使用SFTest 330型自动数字纯音听力计,测定前额安置B71、B81骨振器时于手动及自动模式下纯音骨导阈值,并进行分析比较。结果受试者最大骨导听阈为20 dB HL。B71、B81骨振器于手动、自动模式下测得的纯音骨导阈值间差值平均小于3 dB HL。结论B71、B81骨振器均可应用于前额安置情况下自动测听0.5~4 kHz间纯音骨导阈值,但仍需后续测试不同听损类型及程度人群加以印证。     

Fitting range of the BAHA Cordelle

The performance of the most powerful Bone-Anchored Hearing Aid (BAHA) currently available, the BAHA Cordelle, was evaluated in 25 patients with severe to profound mixed hearing loss. Patients showed bone conduction thresholds at 500, 1000 and 2000 Hz, ranged between 30?and 70 dB HL, and an additional air-bone gap of about at least 30?dB. With the BAHA Cordelle, free-field thresholds improve relative to bone-conduction thresholds with 1.5, 5.0, 17.8, and 4.3 dB at 500, 1000, 2000, and 4000 Hz, respectively, with substantial inter-individual variability. The differences in unaided air conduction thresholds and aided free-field thresholds amount to 45.3, 45.8, 47.5, and 43.5 dB at 500, 1000, 2000, and 4000 Hz, respectively. Speech perception, measured both with monosyllables of the consonant-vowel-consonant type and with bisyllables, showed highly similar results. The fitting range of a (linear) hearing aid is determined by its gain characteristics. Requiring aided speech reception thresholds at or better than 65 dB SPL results in an upper limit of the fitting range of the BAHA Cordelle for bone-conduction thresholds of 51, 56, 67, and 58 dB HL at 500, 1000, 2000, and 4000 Hz, respectively. The dynamic range provided by the BAHA Cordelle was estimated from loudness growth functions at 500, 1500, and 3000 Hz employing 7-point categorical scaling. On average, aided loudness growth functions exhibit normal slopes but they level off at input levels of about 80, 70, 65 dB SPL for 500, 1500, and 3000 Hz stimuli, respectively. Measurements with a skull simulator demonstrated that the levelling-off reflects saturation of the output of the Cordelle. The relatively low saturation levels of the device suggest that increasing maximum output levels may be a worthwhile consideration for candidates with more profound sensorineural loss.     

Effects of expansion algorithms on speech reception thresholds

Expansion is commonly used to reduce microphone noise and low-level environmental noises that can be annoying to hearing aid users. It may also improve or reduce the perception of low-level speech. This study assessed the impact of two expansion algorithms, single and multiple channel, on speech reception thresholds (SRT) with 10 hearing impaired listeners wearing hearing aids with ADRO processing. The single-channel algorithm suppressed sounds below 45 dB A, while the multiple-channel algorithm suppressed sounds below the long-term average spectrum of speech at either 55 or 45 dB SPL. The mean HINT SRTs in quiet were 39.4, 40.7, 40.6, and 41.8 dB A without expansion, with single-channel expansion, and with multiple-channel expansion at expansion thresholds of 45 and 55 dB SPL, respectively. The difference in mean SRT was only statistically significant between no expansion and multiple-channel expansion at a 55 dB SPL threshold. A regression analysis between the change in individual SRT for each expansion condition and pure tone average hearing loss showed no correlation. Our calculations indicate that only those with exceptionally good hearing will find microphone noise audible. The current practice of prescribing expansion algorithms based on hearing thresholds alone is questioned, and other rationales are discussed.     

Estimating the audiogram using multiple auditory steady-state responses

Multiple auditory steady-state responses were evoked by eight tonal stimuli (four per ear), with each stimulus simultaneously modulated in both amplitude and frequency. The modulation frequencies varied from 80 to 95 Hz and the carrier frequencies were 500, 1000, 2000, and 4000 Hz. For air conduction, the differences between physiologic thresholds for these mixed-modulation (MM) stimuli and behavioral thresholds for pure tones in 31 adult subjects with a sensorineural hearing impairment and 14 adult subjects with normal hearing were 14+/-11, 5+/-9, 5+/-9, and 9+/-10 dB (correlation coefficients .85, .94, .95, and .95) for the 500-, 1000-, 2000-, and 4000-Hz carrier frequencies, respectively. Similar results were obtained in subjects with simulated conductive hearing losses. Responses to stimuli presented through a forehead bone conductor showed physiologic-behavioral threshold differences of 22+/-8, 14+/-5, 5+/-8, and 5+/-10 dB for the 500-, 1000-, 2000-, and 4000-Hz carrier frequencies, respectively. These responses were attenuated by white noise presented concurrently through the bone conductor.     

Pure-tone hearing thresholds in otologically healthy 5-year-old children in Finland

Summary We measured the pure-tone air and bone conduction hearing of 359 randomly selected otologically normal urban preschool children in Finland at the average age of 5.2 years. Children with otoscopically verified middle ear pathology or abnormal impedance audiometry were not included in this sample. The mean air conduction thresholds varied from 16.6 dB at 0.125 kHz to 6.6 dB at 2 kHz, and the mean bone conduction thresholds from 6.0 dB at 0.25 kHz to 0.7 dB at 4 kHz. The pure-tone average (of air conduction thresholds at 0.5, 1 and 2 kHz) of all the ears was 7.6 dB. The distribution of single air conduction hearing thresholds at the frequencies from 0.25 kHz to 4 kHz showed that 66%–75% were at the 5–10 dB level.     

听力损失患儿的多频稳态反应测试

目的　探讨多频稳态反应测试对听力损失患儿的临床应用价值。方法　将 2 4 2例聋儿按听力损失程度分成 3组 ,应用Audix测试系统分别测试不同刺激频率、不同刺激强度时的多频稳态反应阈值及假反应的出现率 ,并对其临床应用进行初步评价。结果　在睡眠情况下每一强度刺激的叠加次数在 10～ 2 0次 ,即可得到确定的反应结果 ;当 4个频率同时最大刺激 ,只有个别频率出现反应时要注意排除假反应 ;大多数病例单频或多频同时刺激得到的反应结果差别不大 ,但在少数病例 ,两种测试方法的反应阈值相差可达 15dB ,这可能与听力损失在不同频率处差异程度有关。结论　多频稳态反应测试有较高的临床应用价值及可靠性 ,但在应用时有一些问题也应注意     

健听青年人自动纯音听力计准确性评估

目的测定某型自动数字纯音听力计的气导与骨导纯音阈值检测效度。方法征集健听青年志愿者,使用某型自动数字纯音听力计测试其骨导与气导阈值,并与对应的AC40纯音听力计结果比较,并行统计学分析。结果共21名健听青年受试者入组,自动纯音听力计检测结果与AC40诊断听力计结果比较,气导阈值平均差介于-3.5~5 dB、平均绝对值差介于3.1~5 dB;骨导阈值平均差介于-6.7~0.7 dB,平均绝对值差介于3.2~4.4 dB。除气导平均差较文献结果差异稍大之外,其余结果均与文献报道相应结果相当。结论某型自动数字纯音听力计检测气导与骨导阈值与临床诊断型AC40听力计结果基本相当,但仍需对不同听力损失类型、不同认知能力、不同年龄段人群进一步比较研究。     

The pure-tone hearing thresholds of otologically healthy 14-year-old children

The mean pure-tone air conduction (AC) and bone conduction (BC) hearing thresholds (HT) of 534 randomly selected, caucasian, white, urban children with normal otoscopy, otomicroscopy and impedance audiometry, i.e. normal middle ear function, are presented here. Children with pathological middle ear findings or abnormal impedance audiometry were excluded. The average age was 13.8 years, SD 0.5, at the date of examination. The mean air conduction thresholds varied between 0.6 dB at 1 kHz and 9.9 dB at 6 kHz, and the bone conduction thresholds varied between -1.1 dB at 0.5 kHz and 1.1 dB at 4 kHz. The pure-tone average (PTA) (the average of AC hearing thresholds of 0.5, 1 and 2 kHz) of all ears was 1.5 dB. Ninety to ninety-eight per cent of pure-tone AC hearing thresholds at frequencies of 0.5-4 kHz were between -5 dB and 10 dB. The distributions are presented and compared.