Comparison of auditory steady-state response and click-evoked auditory brain response in infants with different types and degrees of hearing loss

Abstract

Background: Auditory steady-state response (ASSR) and click-evoked auditory brain response (c-ABR) have been used for hearing assessment for decades years, the correlation of the two methods and the effects of type and degree of hearing loss (HL) to the correlation in infants younger than 6?months of age are unclear.

Objectives: To compare the correlation of ASSR and c-ABR and then to analyse the effects of type and degree of HL on the correlation in infants younger than 6?months of age.

Material and methods: Retrospective study comparing ASSR thresholds at various frequencies with c-ABR thresholds. 182 ears from 96 infants were assessed and classified according to types and degrees of HL.

Results: The correlation coefficients were: 0.823, 0.864, 0.891, 0.871, 0.908, 0.915 and 0.913 between ASSR thresholds at 0.5, 1, 2, 4, 2–4, 1–2–4, 0.5–1–2–4?kHz and c-ABR thresholds respectively. The correlation coefficients in the group of sensorineural HL (SHL) (r?=?0.763–0.900) were higher than conductive HL (r?=?0.309–0.619) across all frequencies. The coefficients of severe-profound SHL (r?=?0.595–0.790) were higher than mild-moderate SHL (r?=?0.434–0.687) across all frequencies.

Conclusions and significance: ASSR was one valuable cross-check measure by providing frequency specific information in auditory assessment.     

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.     

Establishing auditory steady-state response thresholds to narrow band CE-chirps in full-term neonates

Narrow band CE-chirps^® were developed to provide a better synchronization of neural response due to the compensation of the traveling wave delay in the basilar membrane. These stimuli combined with a detection method that includes higher response harmonics on the auditory steady-state response (ASSR) recording was studied in this research.     

Auditory steady-state response and auditory brainstem response thresholds in children

The inclusion of the auditory steady-state response (ASSR) into test-batteries for objective audiometry has allowed for clinical comparisons with the most widely used procedure, the auditory brainstem response (ABR). The current study describes ASSR and ABR thresholds for a group of infants and young children with various types and degrees of hearing loss. A sample of 48 subjects (23 female) with a mean age of 2.8 ± 1.9 years SD were assessed with a comprehensive test-battery and classified according to type and degree of hearing loss. Thresholds were determined with a broadband click-evoked ABR and single frequency ASSR evoked with continuous tones (0.25–4 kHz) amplitude modulated (67–95 Hz). Mean difference scores (±SD) between the ABR and high frequency ASSR thresholds were 9.8 (±11), 3.6 (±12) and 10.5 (±12) dB at 1, 2 and 4 kHz, respectively. An ASSR mean threshold for 2–4 and 1–4 kHz compared to the ABR threshold revealed an average difference of 7 (±9) and 7.9 (±8) dB, respectively. The overall correlation between the ABR and ASSR thresholds was highest for the mean ASSR thresholds of 2–4 and 1–4 kHz (r = 0.92 for both conditions). Correlations between the ABR and individual ASSR frequencies were slightly less (0.82–0.86). The average of the 2–4 kHz ASSR thresholds correlated best with the click-evoked ABR for all categories of hearing loss except for the sensorineural hearing loss category for which the 1–4 kHz ASSR average was better correlated to ABR thresholds. Findings demonstrate the reliability of verifying high frequency ASSR thresholds with a click-evoked ABR as an important cross-check in infants for whom behavioural audiometry may not be possible.     

Comparison of ABR response amplitude,test time,and estimation of hearing threshold using frequency specific chirp and tone pip stimuli in newborns

Abstract

Objective: To evaluate the auditory brainstem response (ABR) amplitudes evoked by tone pip and narrowband chirp (NB CE-Chirp) stimuli when testing post-screening newborns and to determine the difference in estimated hearing level correction values. Design: Tests were performed with tone pips and NB CE-Chirps at 4 kHz or 1 kHz. The response amplitude, response quality (Fmp), and residual noise were compared for both stimuli. Study sample: Thirty babies (42 ears) who passed our ABR discharge criterion at 4 kHz following referral from their newborn hearing screen. Results: Overall, NB CE-Chirp responses were 64% larger than the tone pip responses, closer to those evoked by clicks. Fmp was significantly higher for NB CE-Chirps. Conclusion: It is anticipated that there could be significant reductions in test time for the same signal to noise ratio by using NB CE-Chirps when testing newborns. This effect may vary in practice and is likely to be most beneficial for babies with low amplitude ABR responses. We propose that the ABR nHL threshold to eHL correction for NB CE-Chirps should be approximately 5 dB less than the corrections for tone pips at 4 and 1 kHz.     

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。     

脑性瘫痪患儿听性脑干反应及多频稳态听性反应分析

目的：通过听性脑干诱发反应（ABR）及听性稳态反应（ASSR）分析，探讨脑性瘫痪（脑瘫）患儿的听力障碍及脑干听通道功能变化。方法：采用美国GSIAudera听性脑干反应及听性稳态诱发电位测试仪，测试脑瘫患儿52例104耳。对照组为同龄健康儿童19例38耳。结果：脑瘫组患儿的ABR各波潜伏期及峰间潜伏期均较对照组明显延长；脑瘫组ASSR结果以轻度低频听力损失为著，并且各频率听力损失的平均值非常接近。结论：ABR和ASSR同时应用，为脑瘫患儿听力损失进行定性定量诊断提供了客观的测试方法。     

Assessment of low-frequency hearing with narrow-band chirp-evoked 40-Hz sinusoidal auditory steady-state response

Objective To determine the clinical utility of narrow-band chirp-evoked 40-Hz sinusoidal auditory steady state responses (s-ASSR) in the assessment of low-frequency hearing in noisy participants. Design Tone bursts and narrow-band chirps were used to respectively evoke auditory brainstem responses (tb-ABR) and 40-Hz s-ASSR thresholds with the Kalman-weighted filtering technique and were compared to behavioral thresholds at 500, 2000, and 4000?Hz. A repeated measure ANOVA and post-hoc t-tests, and simple regression analyses were performed for each of the three stimulus frequencies. Study sample Thirty young adults aged 18–25 with normal hearing participated in this study. Results When 4000 equivalent response averages were used, the range of mean s-ASSR thresholds from 500, 2000, and 4000?Hz were 17–22?dB lower (better) than when 2000 averages were used. The range of mean tb-ABR thresholds were lower by 11–15?dB for 2000 and 4000?Hz when twice as many equivalent response averages were used, while mean tb-ABR thresholds for 500?Hz were indistinguishable regardless of additional response averaging. Conclusion Narrow-band chirp-evoked 40-Hz s-ASSR requires a ～15?dB smaller correction factor than tb-ABR for estimating low-frequency auditory threshold in noisy participants when adequate response averaging is used.     

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。     

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     

Further comparisons of ABR response amplitudes,test time,and estimation of hearing threshold using frequency-specific chirp and tone pip stimuli in newborns: Findings at 0.5 and 2 kHz

Objective: To compare auditory brainstem response (ABR) amplitudes evoked by 0.5 and 2 kHz tone pip and narrowband chirp (NB CE-Chirp) stimuli when testing post-screening newborns. To determine the difference in ‘estimated hearing level’ correction values. Design: Tests were performed with tone pips and NB CE-Chirps at 0.5 or 2 kHz and the ABR threshold for each stimulus defined. Response amplitude, response quality (Fmp), and residual noise were compared for both stimuli. Study sample: Thirty-nine babies (42 ears) who passed our ABR discharge criterion at 4 kHz following referral from their newborn hearing screen. Results: NB CE-Chirp responses were, on average, 31% larger than the tone pip responses at 0.5 kHz and were 52% larger at 2 kHz. Fmp was significantly higher for NB CE-Chirps. Conclusions: The advantages of NB CE-Chirps over tone pips we previously identified at 4 and 1 kHz extends to 0.5 and 2 kHz, which supports the use of NB CE-Chirps when testing newborns. We propose that ABR nHL threshold to eHL corrections for NB CE-Chirps should be approximately 5 dB less than corrections for tone pips at 0.5 and 2 kHz, mirroring our recommendation at 4 and 1 kHz.     

Estimating audiometric thresholds using simultaneous acquisition of ASSR and ABR from QASSR in patients with sensorineural hearing loss

Objectives: To evaluate the accuracy with which the innovative QASSR method predicts behavioral thresholds in adult patients with sensorineural hearing loss. Design: Subjects were tested at four carrier frequencies (500, 1000, 2000, and 4000?Hz).The resulting QASSR recordings were analyzed for thresholds and magnitude/phase characteristics. Tone-burst ABR was recovered from QASSR signal using CLAD method and analyzed in the time domain. The electrophysiological estimates were compared to hearing thresholds determined behaviorally. Study sample: Sixteen ears of nine volunteer subjects recruited from a clinical population. Results: All mean threshold estimates differed less than 3?dB for QASSR and less than 5?dB for ABR at 1000, 2000 and 4000Hz (carrier or pure-tone test frequencies). The largest differences were observed for both at 500?Hz (5.63 and 11.56?dB respectively).The audiometric configurations of QASSR and ABR estimates followed those of the respective behaviorally determined configurations across ears tested. Conclusions: QASSR method merges two dissimilar stimulation techniques, transient and steady-state, to create a hybrid stimulation-and-analysis paradigm that seems to improve the overall performance of the electrophysiological threshold estimation. The unique feature of the QASSR technique is the additional information afforded by the transient ABR, recovered from the same recording. The QASSR thus holds promise to be a very useful tool for practical clinical applications.     

0～6岁听力损失儿童短纯音诱发的听性脑干反应研究

目的比较听力损失儿童短纯音听性脑干反应（auditory brainstem response，ABR）反应阈与40Hz听觉事件相关电位（auditory event-related potentials，AERP）及短声ABR反应阈的相关性，评价短纯音ABR在儿童听力评估中的应用。方法应用SmartEP听觉诱发电位仪在0～6岁听力损失儿童中记录短声、短纯音ABR及40 Hz AERP的反应阈，共43例85耳（男／女=27／16）。结果0．5、1、2kHz短纯音ABR反应阈与40 Hz AERP反应阈的线性相关系数分别为0．84、0．80、0．80，反应闯之差分别为3．6±12．2、5．9±14．8、1．7±13.7dB。0．5、1、2、4kHz短纯音ABR反应阈与短声ABR反应阈的线性相关系数分别为0．81、0．89、0．94、0．91，反应阈之差分别为6．6±13．4、0．2±10．7、1．5±8．1、4．2±10．2dB。2kHz、4kHz短纯音反应阈的平均值与短声ABR反应阈的线性相关系数为0．93，反应阈之差为2．8±8．3dB。结论短纯音ABR的反应阈可作为一种儿童听力评估的方法。     

2035例婴儿听性脑干反应与多频稳态反应阈值的比较

目的 探讨婴儿听性脑干反应(auditorybrainstem response,ABR)与多频稳态反应(auditorysteady-state response,ASSR)的关系.方法 对2035例婴儿进行ABR和ASSR检测,结果采用SPSS 17.0进行相关分析、t检验和直线回归分析.结果 ①ABR反应阈与ASSR不同频率反应阈值的相关系数为0.732～0.915 (P＜0.05).②在t检验中,ABR反应阈值与ASSR 4 kHz反应阈值差异无统计学意义(P＞0.05),其余比较差异均有意义(P＜0.05).③ABR预测ASSR0.5、1、2、4 kHz、高频均值、均值的回归方程分别为:y=0.979x-6.921,y=0.909x-1.705,y=0.948x-3.647,y=1.117x-5.113,y=1.033x-4.380,y=0.988x-4.346.结论 婴儿ABR与ASSR反应阈值具有较好的相关性,其主要是反映ASSR 4 kHz的反应阈值.     

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.     

听性稳态诱发反应在听力异常婴儿的诊断意义

目的听性稳态诱发反应（auditory steady—statere sponse，ASSR）新技术与视觉强化测听（vision reinforcement audiometry，VRA）阈值的相关性分析研究，探讨听神经病症侯群及其鉴别诊断。方法10例（20耳）对照组，年龄6～12个月，测得ASSR和VRA的正常阈值。16例（26耳）异常听力组患儿（年龄在3～6个月），根据其所患疾病分为3个亚组：Ⅰ组为早孕感染组5例（8耳），Ⅱ组为窒息缺氧组5例（10耳），Ⅲ组为高胆红素血症组6例（8耳），检测畸变产物耳声发射（DPOAE）、听性脑干反应（ABR）潜伏期、肌反射值与ASSR和VRA及其相关性结果对照。结果Ⅰ组中2例次（2耳次）为单纯疱疹病毒感染。5例次（8耳次）DPOAE消失，4例次（6耳次）ABR波Ⅰ潜伏期延长、Ⅰ—Ⅴ波间潜伏期缩短，3例次（6耳次）500Hz和1000Hz的镫骨肌反射正常，2例次（2耳次）镫骨肌反射阈偏高，初步推测单纯耳蜗性病变，排除听神经病可能，测得ASSR平均估计阈值与VRA平均阈值具有很好的相关性（r=0．95～0．98）。Ⅱ组中4例次（8耳次）畸变产物耳声发射消失，其中1例次（2耳次）ABR波Ⅰ、波Ⅲ、波Ⅴ消失和肌反射消失，3例次（5耳次）ABR波Ⅰ消失和波Ⅲ及波Ⅴ潜伏期延长，以及肌反射消失。2例次（3耳次）Ⅰ-Ⅲ波间潜伏期延长，肌反射也消失。推测可能为听神经病症侯群（耳蜗至脑干下听觉传导通路受损）伴有耳蜗功能障碍，测得ASSR平均估计阈值与VRA平均阈值具有较好的相关性（r=0．72～0．84）。Ⅲ组中6例次（8耳次）DPOAE存在，4例次（5耳次）ABR波Ⅰ、Ⅲ、Ⅴ和肌反射消失，2例次（3耳次）Ⅰ—Ⅴ波间潜伏期延长，镫骨肌反射阈正常偏高，初步分析推测为听神经病症侯群病损在脑干以上，测得ASSR平均估计阈值与VRA平均阈值具有很弱的相关性（r=0．43～0．64），ASSR阈值和VRA阈值不一致，进一步说明这组的病损应该在脑干或皮层。3个亚组的每个频率（0．25、0．5、1、2,4kHz）平均ASSR和VRA阈值差值比较，差异都具有统计学意义（F检验，P〈0．05、P〈0．01、P〈0．01、P〈0．05、P〈0．05）。结论通过ASSR阈值和VRA阈值相关性技术研究或许可提供诊断及鉴别诊断在各种频率听力障碍婴儿的听神经病症侯群（病变高位）、听神经病症侯群伴有耳蜗功能障碍（病变低位）以及单纯耳蜗性病（非听神经病）。     

双侧耳蜗切除术致听力剥夺大鼠的听性脑干反应改变

目的：通过比较大鼠在双侧耳蜗切除术后不同时间点听性脑干反应（ABR）的变化,探讨ABR在测试听力剥夺大鼠模型中的应用价值。方法：选取2周龄SD大鼠40只,随机分为实验组4组（2周组、4周组、6周组、8周组）和对照组4组,每组5只（10耳）。实验组动物在双侧耳蜗损毁术后不同时间点与其对照组行ABR检测,记录ABR阈值及各波潜伏期和波间期。结果：实验组ABR反应阈明显升高,与对照组相比,差异有统计学意义（P〈0．01）,各波潜伏期和波间期明显延长（P〈0．01）;实验2周组、4周组与6周组和8周组相比,ABR反应阈的差异也有统计学意义（P〈0．01）。结论：双侧耳蜗切除术可导致大鼠ABR反应阈明显增高,各波潜伏期和波间期明显延长;听力剥夺效果从术后4周开始越发明显。     

ASSR、Tb-ABR和c-ABR在正常听力人群客观听阈评估中的相关性分析

目的：研究多频听觉稳态反应（ASSR）、短纯音听觉脑千诱发电位（Tb-ABR）和短声听觉脑干诱发电位（c-ABR）反应阈与纯音听阈（PTA）在正常听力人群中的差别和相关性。方法：对正常听力的受试者（共58耳）进行ASSR、Tb-ABR和c-ABR以及纯音测听检查,分别得出前三者测试的反应阂并与PTA进行相关性分析。结果：ASSR和Tb-ABR的反应阈均与同频率的PTA具有良好的相关性;Tb-ABR的反应阈与PTA的值接近,ASSR反应阈与PTA间的差值较大;c-ABR与PTA2、4kHz听阈的均值呈线性相关。结论：ASSR和Tb-ABR都是较好的评估行为听阚的频率特异性客观测听方法,Tb-ABR结合c-ABR能较好地反映PTA。     

Speech-evoked auditory brainstem response with ipsilateral noise in adults with unilateral hearing loss

Introduction: Subjects with unilateral hearing loss (UHL) report difficulties in speech understanding in noise. Speech-evoked auditory brainstem response (S-ABR) provides cues for temporal and spectral encoding of speech in the brainstem. S-ABR recording in noise increases its sensitivity in evaluating the auditory processing and related disorders.

Objectives: Study speech encoding at the level of brainstem when the auditory system relies on one ear and to study the effect of noise on this encoding.

Subjects and method: This study included two groups: control group consisted of 15 adults with normal hearing sensitivity and study group consisted of 30 adults with UHL. The study group was further subdivided into two subgroups: study subgroup A (SG A) consisted of 15 adults with right functioning ears and study subgroup B (SG B) consisted of 15 adults with left functioning ears. S-ABR in quiet and with ipsilateral noise was recorded in both the groups using complex ABR advanced auditory research module.

Results: In UHL, there was a statistically significant delay in the S-ABR onset and offset in noise compared to quiet. Moreover, quiet–noise (+5 SNR) correlation was significantly low compared to NH. Furthermore, pitch representation (F0 amplitude) was significantly degraded with noise. In addition, there was a statistically significant noise-induced phase shift in the transition region of speech syllable in these subjects.

Conclusion: In monaural processing, pitch representation (F0 amplitude) and cross-phaseogram were the main affected domains. Speech phonemes of transient origin can be confused in subjects with UHL.     

Evaluation of residual hearing in cochlear implants candidates using auditory steady-state response

Conclusion: The correlations between behavioral and auditory steady-state response (ASSR) thresholds were significant at 500, 1000, 2000, and 4000 Hz. ASSR presented high sensitivity and specificity in the detection of residual hearing in cochlear implant candidates when compared with warble-tone audiometry. Objectives: To assess residual hearing in cochlear implant candidates by comparing the electrophysiological thresholds obtained in dichotic single-frequency ASSR with behavioral thresholds at 500, 1000, 2000, and 4000 Hz. Methods: This was a comparative study between ASSR and warble-tone audiometry thresholds in 40 cochlear implant candidates (80 ears) before cochlear implantation with bilateral severe-to-profound sensorineural hearing loss. Results: Thresholds were obtained in 62.5% of all frequencies evaluated in warble-tone audiometry and in 63.1% in the ASSR. ASSR sensitivity was 96% and specificity was 91.6%. Mean differences between behavioral and ASSR thresholds did not reach significance at any frequencies. Strong correlations between behavioral and ASSR thresholds were observed in 500, 1000, and 2000 Hz and moderate in 4000 Hz, with correlation coefficients varying from 0.65 to 0.81. On 90% of occasions, ASSR thresholds were acquired within 10 dB of behavioral thresholds.