Bimodal benefits in Mandarin-speaking cochlear implant users with contralateral residual acoustic hearing

Abstract

Objective: The present study aimed to measure bimodal benefits and probe their underlying mechanisms in Mandarin-speaking cochlear implant (CI) subjects who had contralateral residual acoustic hearing. Design: The subjects recognised words or phonemes from the Mandarin Lexical Neighborhood Test in noise at a 10-dB signal-to-noise ratio (SNR) with acoustic stimulation, electric stimulation or the combined bimodal stimulation. Study sample: Thirteen Mandarin-speaking subjects wore a CI in one ear and had residual acoustic hearing in the contralateral ear. Six of the subjects (5.2–13.0 years) had pre-lingual onset of severe hearing loss, and seven of them (8.6–45.8 years) had post-lingual onset of severe hearing loss. Results: Both groups of subjects produced a significant bimodal benefit in word recognition in noise. Consonants and tones accounted for the bimodal benefit. The bimodal integration efficiency was negatively correlated with the duration of deafness in the implanted ear for vowel recognition but positively correlated with CI or bimodal experience for consonant recognition. Conclusions: The present results support preservation of residual acoustic hearing, early cochlear implantation and continuous use of bimodal hearing for subjects who have significant residual hearing in the non-implanted ear.     

Effects of loss of residual hearing on speech performance with the CI422 and the Hybrid-L electrode

Abstract

Objective

Preservation of residual low-frequency hearing has become a priority in cochlear implantation. The purpose of this study was to compare rates of hearing preservation and effects on performance of loss of low-frequency acoustic hearing with two different length electrodes.

Study design

Retrospective chart review.

Setting

Tertiary Care Hospital.

Patients

Twelve patients were implanted with the CI422 a slim-straight electrode; the second group consisted of 10 patients implanted with the Hybrid-L, a shorter hearing preservation electrode.

Main outcome measure

Audiometric thresholds and speech perception measures.

Results

At 1 year, 3/10 (30%) patients with the Hybrid-L and 7/12 (58%) patients with the CI422 lost residual acoustic hearing resulting in a profound hearing loss in the implanted ear. In comparing these patients in particular, mean CNC words in the implanted ear were 72% in the CI422 electrode group and 15% in the Hybrid-L electrode group at 1 year (P = 0.03). While hearing preservation rates with the Hybrid-L tended to be better, among recipients who lost residual hearing, speech perception was better in those with the longer CI422 electrode.

Conclusions

With emphasis on preservation of residual hearing, patients need to be counseled regarding possible outcomes and options should loss of residual hearing occur following implantation. While shorter electrodes may have better rates of hearing preservation, the patients with the longer straight electrode in our study had significantly better speech understanding following the loss of residual hearing.     

有低频残余听力感音神经聋的人工耳蜗植入术

目的介绍一种有低频残余听力感音神经聋的人工耳蜗植入技术,探讨人工耳蜗植入手术对有残余听力患者的治疗效果和价值。方法15例有残余听力的患者接受了保护残余听力的人工耳蜗植入手术。术中电极植入深度在19mm～24mm左右。术后分别检测单纯使用助听器、单纯使用人工耳蜗、人工耳蜗结合助听器三种不同状态下的听力。结果15例患者中,有13例术后残余听力保存良好,仅分别丢失5～20dB听力,但另2例术后残余听力全部丧失。术后在安静、信噪比15dB和10dB三种不同状态下的言语测试结果显示,人工耳蜗结合助听器使用者测试得分始终保持在很高水平;单纯使用人工耳蜗者也有较好的成绩,但在信噪比达10dB的条件下,测试成绩下降;而单纯使用助听器者,不仅在安静状态下听力成绩不甚理想,一旦加入竞争性噪声,听力测试成绩急剧下降。结论保护和利用残余听力的人工耳蜗植入技术,使人工耳蜗植入手术对象从重度或极重度聋扩大到高频为重度或极重度聋,低频（≤500Hz）为中、轻度聋的患者。接受这项技术患者的听力和言语识别能力均明显优于其单纯配戴助听器和单纯使用人工耳蜗时的听力和言语识别能力。     

语前聋患儿一侧人工耳蜗对侧助听器效果分析

目的:通过对人工耳蜗植入对侧耳不同听力损失的患儿联合使用助听器与人工耳蜗语前聋患儿的听觉、语言及学习能力进行评估和比较,探索对患儿更为有效的助听方法,帮助患儿获得最大限度的言语交流。方法:将30例3～6岁语前聋患儿按照植入人工耳蜗对侧耳听力损失程度及是否佩戴助听器,分为一侧人工耳蜗+对侧重度听力损失助听器组(CI+SHA组)、一侧人工耳蜗+对侧极重度听力损失助听器组(CI+PHA组)、单耳人工耳蜗组(CI组)。评估各组在康复3、6、9、12、15、18个月时听觉、语言及学习能力,并记录结果。结果:随着术后康复时间的延长,聋儿听觉、语言及学习能力逐渐提高(P<0.05),CI+SHA组听觉能力优于CI+PHA组及CI组(均P<0.05),语言能力及学习能力无明显差异(P>0.05)。结论:语前聋患儿单耳人工耳蜗植入后,若对侧耳尚有残余听力,佩戴助听器后听觉能力效果显著,长期佩戴有助于患儿的康复。     

语前聋患儿一侧人工耳蜗植入对侧佩戴助听器聆听效果分析

目的：分析语前聋患儿一侧人工耳蜗植入（cochlear implant ,CI）对侧佩戴助听器模式下的聆听效果,以及非植入耳残余听力对聆听效果的影响。方法选取一侧人工耳蜗植入对侧佩戴助听器的语前聋患儿18例,分别测试其在单侧人工耳蜗植入、一侧人工耳蜗植入对侧佩戴助听器的双耳聆听模式（ bimodal fitting ,BIM ）安静环境及稳态噪声环境下标准中文短句、双音节词、单音节词的识别率。结果安静状态下本组患儿CI、BIM 模式单音节词言语识别率分别为82．67％±12．23％、83．61％±12．22％,双音节词分别为76．00％±16．13％、78．11％±14．84％,标准中文短句分别为60．11％±17．18％、65．43％±16．76％;信噪比10 dB环境下CI、BIM 助听模式患儿单音节词识别率分别为75．50％±14．12％、76．83％±14．15％,双音节词分别为68．22％±17．15％、77．18％±16．83％,标准中文短句分别为49．39％±19．26％、56．33％±19．55％,除两种模式下单音节词外其余言语识别率差异均有统计学意义（P＜0．05）,且非植入耳250、500 Hz助听听阈与BIM 模式言语识别率呈负相关。结论语前聋患儿双耳双模式聆听时有一定优势,这种优势可能主要来自低频残余听力。     

Natural history of contralateral residual hearing in binaural-bimodal hearing

Conclusions. The range of evaluation tools used in deciding which ear to implant and which to designate for a hearing aid (HA) should be expanded to include additional aspects to those tested by audiometry and basic speech perception. Residual hearing in non-implanted ears remains stable for at least 3 years after unilateral cochlear implantation, but regular refitting and monitoring of the HA function combined with cochlear implant (CI) mapping are mandatory for maximizing benefit from binaural-bimodal hearing. Objectives. To examine whether the clinical decision-making tools currently used to assess hearing are reliable guides when choosing the preferred ear for CI, and to determine the rate of residual hearing deterioration in the non-implanted ear over 36 months post-CI as a guide to recommending subsequent continued use of a contralateral HA as opposed to CI. Patients and methods. This was a retrospective evaluation of patients’ charts. The pre-CI choice of the ear for implantation in a group of 37 binaural-bimodal users was re-evaluated. In a second group of 22 patients, residual hearing deterioration was followed for 36 months post-implantation. Results. In the group of 37 patients, subjective identification of the worse-hearing ear was in agreement with audiometric results in 28 cases, but disagreed with the unaided audiometric results in the other 9. Mean threshold values for the group of 22 patients remained stable over 36 months post-CI, except for the aided threshold at 4.0kHz, which deteriorated by 10.9dB (p=0.003).     

Advantages of binaural hearing provided through bimodal stimulation via a cochlear implant and a conventional hearing aid: A 6-month comparative study

Conclusions

Our study data demonstrate the additional benefit derived from continued use of a contralateral hearing aid (HA) post-cochlear implantation for speech recognition ability in quiet and in noise. Postoperative bimodal stimulation is recommended for all subjects who show some speech recognition ability in the contralateral ear as it may offer binaural listening advantages in various listening situations encountered in everyday life.

Objectives

To assess the benefits derived from bimodal stimulation for experienced HA users implanted with a cochlear implant (CI) (score?≥?20% in disyllabic test). The correlation between pre- and postoperative performance on speech perception measures was examined to determine additional criteria for recommending bimodal stimulation postoperatively.

Material and methods

A within-subject repeated-measures design was used, with each subject acting as their own control. Assessments were carried out preoperatively in aided monaural and best-aided conditions and at 6 months postoperatively in CI-alone, contralateral HA-alone and bimodal listening conditions. Speech recognition using Spanish words and sentences materials was assessed at conversational level and for soft speech in quiet. Speech comprehension in noise was assessed using word materials at a signal:noise ratio of +10, for coincident speech in noise and for spatially separated speech in noise. Twelve adult native Spanish subjects with a severe-to-profound hearing impairment who were experienced with optimally fitted conventional amplification and who displayed suboptimal speech understanding preoperatively were enrolled in the study. Preoperatively, conventional amplification was worn by five subjects binaurally and by seven monaurally.

Results

Postoperatively, superior speech recognition ability in quiet and in noise for disyllabic words was achieved using bimodal stimulation in comparison to performance for either monaural aided condition. Mean improvement in speech recognition in the bimodal condition was significant over performance in the CI-alone condition for disyllabic words in quiet at 70 (p=0.006) and 55 dB SPL (p=0.028), for disyllabic words in noise at +10 dB with speech and noise spatially separated with the noise source closest to the contralateral HA (S0NHA) (p=0.0005) and when the noise source was closest to the CI ear (S0NCI) (p=0.002). When testing word recognition in noise with speech and noise sources coincident in space, word scores were superior in the bimodal condition relative to the CI-alone condition but this improvement was not significant (p=0.07). The advantages of bimodal stimulation included significant effects of binaural summation in quiet and significant binaural squelch effects in both the S0NHA and S0NCI test conditions. All subjects showed superior performance in the binaural situation postoperatively relative to the best-aided condition preoperatively for one or more test situations.     

What to do with the other ear after cochlear implantation

Unilateral cochlear implantation has become a widely accepted surgical intervention for both deaf children and adults. It is a reliable and effective method to rehabilitate profound deafness. Recently the benefits of the use of a contralateral hearing aid (bimodal stimulation) with a cochlear implant became clear. Bilateral cochlear implantation benefits bilateral input into the auditory system for adults and children. To provide the binaural advantages experienced by normal hearing subjects bilateral cochlear implantation or bimodal stimulation is probably indicated. Whether to choose between both possibilities depends on many factors. Cortical auditory evoked potential (CAEP) measurements can be an important tool to decide bilateral implantation in young children. Enough residual hearing in the non-implanted ear might benefit from bimodal stimulation. New protocols are needed for the audiological management for recipients of cochlear implants.     

Utility of bilateral acoustic hearing in combination with electrical stimulation provided by the cochlear implant

Abstract

Objective: The aim of the study was to quantify the benefit provided by having access to amplified acoustic hearing in the implanted ear for use in combination with contralateral acoustic hearing and the electrical stimulation provided by the cochlear implant. Design: Measures of spatial and non-spatial hearing abilities were obtained to compare performance obtained with different configurations of acoustic hearing in combination with electrical stimulation. In the combined listening condition participants had access to bilateral acoustic hearing whereas the bimodal condition used acoustic hearing contralateral to the implanted ear only. Experience was provided with each of the listening conditions using a repeated-measures A-B-B-A experimental design. Study sample: Sixteen post-linguistically hearing-impaired adults participated in the study. Results: Group mean benefit was obtained with use of the combined mode on measures of speech recognition in coincident speech in noise, localization ability, subjective ratings of real-world benefit, and musical sound quality ratings. Conclusions: Access to bilateral acoustic hearing after cochlear implantation provides significant benefit on a range of functional measures.     

Cochlear implant and hearing aid: a new approach to optimizing the fitting in this bimodal situation

More and more patients with residual hearing on the contralateral side are becoming candidates for cochlear implants (CI) surgery due to increasing CI. The major benefits of regular binaural hearing are spatial hearing, localization, and signal source discrimination in both quiet and noisy surroundings. In most of the reports, hearing aid fitting was carried out without balancing both the devices. Twelve children and eight adults with residual hearing on the non-operated side were binaurally fitted. Our fitting procedure for the hearing aid was based on the desired sensation level [i/o] method. A loudness scaling was used to adjust the loudness perception monaurally and to balance the volume of both devices. Speech audiometry in quiet and noisy surroundings was conducted both monaurally and in the bimodal mode. The fitting was modified according to the respective test results. In all children and six adults, a measurable gain and/or a subjective improvement of speech perception was achieved. Two adult patients did not accept the new fitting. In seven younger children, loudness scaling was impossible to perform because of age. This was also the case with speech audiometry for two children. A structured bimodal fitting using loudness scaling for both the cochlear implant and the hearing aid results in a subjective and objective amelioration of the patient’s hearing and speech perception.     

Loss of residual hearing after cochlear implantation

Many cochlear implant recipients have some measurable hearing prior to implantation. Animal studies have demonstrated some loss of viable neural elements resulting from both mechanical insertion trauma and long-term electrical stimulation. The effect of implantation of a long intracochlear multichannel electrode array and subsequent electrical stimulation on residual hearing was evaluated. Forty consecutive cochlear implant recipients were assessed by audiometry at the Colorado Ear Clinic between July 1985 and June 1988. Twelve of these patients (30%) had some measurable residual hearing before implantation, although all had profound hearing loss, with no understanding of speech. All patients received a multichannel cochlear implant with all 22 electrodes inserted in each patient by an experienced cochlear implant surgeon. Audiometric testing was repeated between 2 and 24 months after implantation. Pure-tone threshold responses in the implanted ear were significantly reduced postimplant, while puretone threshold responses in the nonimplanted ear were stable.     

Sequential bilateral cochlear implantation improves working performance,quality of life,and quality of hearing

Conclusions: This prospective study shows that working performance, quality of life (QoL), and quality of hearing (QoH) are better with two compared with a single cochlear implant (CI). The impact of the second CI on the patient’s QoL is as significant as the impact of the first CI. Objectives: To evaluate the benefits of sequential bilateral cochlear implantation in working, QoL, and QoH. Methods: We studied working performance, work-related stress, QoL, and QoH with specific questionnaires in 15 patients with unilateral CI scheduled for sequential CI of another ear. Sound localization performance and speech perception in noise were measured with specific tests. All questionnaires and tests were performed before the second CI surgery and 6 and 12 months after its activation. Results: Bilateral CIs increased patients’ working performance and their work-related stress and fatigue decreased. Communication with co-workers was easier and patients were more active in their working environment. Sequential bilateral cochlear implantation improved QoL, QoH, sound localization, and speech perception in noise statistically significantly.     

Cochlear implant in patients with residual hearing

Objective: The postoperative speech perception abilities of severely hearing-impaired patients with multi-channel cochlear implant were compared with preoperative speech perception performance with conventional hearing aids. Methods: Cochlear implantation was performed in six severely to profoundly hearing-impaired patients. They had unaided pure-tone thresholds of 70–100-dB HL and aided thresholds of 35–90-dB HL in the better ear, but were not able to perceive speech sounds well with hearing aids. Results: Postoperatively, all the patients had significantly improved speech perception performance, exceeded the average skills of profoundly deaf cochlear implant users, and were able to communicate without writing. Conclusion: These results imply that cochlear implant may be indicated for severely to profoundly deaf subjects, if they receive little or no benefit from conventional hearing aids.     

Speech perception for adults who use hearing aids in conjunction with cochlear implants in opposite ears.

This study aimed to (a) investigate the effect of using a hearing aid in conjunction with a cochlear implant in opposite ears on speech perception in quiet and in noise, (b) identify the speech information obtained from a hearing aid that is additive to the information obtained from a cochlear implant, and (c) explore the relationship between aided thresholds in the nonimplanted ear and speech perception benefit from wearing a hearing aid in conjunction with a cochlear implant in opposite ears.Fourteen adults who used the Nucleus 24 cochlear implant system in 1 ear participated in the study. All participants had either used a hearing aid in the nonimplanted ear for at least 75% of waking hours after cochlear implantation, and/or, hearing loss less than 90 dB HL in the low frequencies in the nonimplanted ear. Speech perception was evaluated in 3 conditions: cochlear implant alone (CI), hearing aid alone (HA), and cochlear implant in conjunction with hearing aid in opposite ears (CIHA). Three speech perception tests were used: consonant-vowel nucleus-consonant (CNC) words in quiet, City University of New York style (CUNY) sentences in coincident signal and noise, and spondees in coincidental and spatially separated signal and noise. Information transmission analyses were performed on the CNC responses.Of the 14 participants tested, 6 showed significant bimodal benefit on open-set speech perception measures and 5 showed benefit on close-set spondees. However, 2 participants showed poorer speech perception with CIHA than CI in at least 1 of the speech perception tests. Results of information transmission analyses showed that bimodal benefit (performance with CIHA minus that with CI) in quiet arises from improved perception of the low frequency components in speech. Results showed that participants with poorer aided thresholds in the mid-to-high frequencies demonstrated greater bimodal benefit. It is possible that the mid-to-high frequency information provided by the hearing aids may be conflicting with the cochlear implants.     

Natural history of contralateral residual hearing in unilateral cochlear implant users - long-term findings

Abstract Conclusion: The long-term stability of low-frequency residual hearing found in a significant number of bilateral-bimodal users (cochlear implant (CI) in one ear and a hearing aid (HA) on the other ear; CI/HA) with severe-to-profound or profound hearing loss in the non-implanted ear justifies bilateral-bimodal fitting efforts in this group. Since low-frequency residual hearing tends to deteriorate in some of these CI/HA users, periodic evaluation, which includes pure-tone thresholds and speech perception tests, is mandatory for determining the point in time at which CI/HA hearing is no longer effective, and the patient should accordingly be considered as a candidate for contralateral cochlear implantation. Objective: To determine, in bilateral-bimodal (CI/HA) users with severe-to-profound or profound hearing loss in the non-implanted ear, the rate of residual hearing deterioration in the non-implanted ear after cochlear implantation. Methods: Pure-tone aided and unaided thresholds in the non-implanted ears of 39 CI/HA users at 0.25-4.0 kHz were recorded prospectively up to 6 years after implantation. Results: Group mean threshold values in the non-implanted ears remained stable over 3, 4, 5 and 6 years post-implantation, except for significant deterioration at 4.0 kHz of both unaided (4.2, 5.2, 9.0 and 8.2 dB, respectively) and aided thresholds (8.1, 4.6, 6.1 and 8.3 dB, respectively).     

Hearing restoration in NF2 patients and patients with vestibular schwannoma in the only hearing ear: report of two cases

Objective

To explore audiologic outcome of auditory brain stem implantation (ABI) and cochlear implantation (CI) in NF2 patients and patients with vestibular schwannoma (VS) in the only hearing ear.

Patients and methods

Study includes retrospective analysis of 2 cases. One is totally deaf patient due to NF2, and the other one is totally deaf due to VS development in only hearing ear. Tumor was removed by retrosigmoid approach in NF2 patient and ABI was performed simultaneously. For the VS in only hearing ear case, tumor was removed by translabyrinthine approach and CI was performed simultaneously.

Results

ABI patient showed quite well outcome during the 15 months of follow-up. She has 25 dB hearing threshold at speaking frequencies. She developed open set speech discrimination with 87.5% word discrimination score, and 70% sentence discrimination score. She uses device daily manner, she can use telephone. For CI patient, outcome is not perfect but satisfactory. She couldn’t develop open set speech discrimination during the 18 months of follow-up. She has 67% the disyllabic words recognition score (close set). She is daily user of device. CI improves quite well lip reading.

Conclusion

ABI and CI are the two options to restore hearing in VS caused deafness. We advocate giving every effort to preserve cochlear nerve during the VS resection and place CI simultaneously. However if it is not possible to preserve cochlear nerve during surgery, ABI is also a good alternative for hearing restoration.     

L-N-Acetylcysteine treatment is associated with improved hearing outcome in sudden idiopathic sensorineural hearing loss

Conclusions. Universal hearing screening gives a deaf child earlier diagnosis and intervention with a better chance for successful management of hearing and speech development. Objectives. Universal newborn hearing screening has a major impact on early identification of deafness in children. This study evaluated the outcome of cochlear implantation in screened and non-screened deaf children. Subjects and methods. Group 1 comprised 9 deaf children diagnosed by screening; group 2 comprised 21 children diagnosed by traditional methods. The following parameters were evaluated: age at the time of diagnosis, age at the time of the first hearing aid fitting, age at the time of cochlear implantation. In children who had been using a cochlear implant for more than 2 years the results of audiological tests, category of auditory performance (CAP), and development and quality of speech were also evaluated. Results. Hearing screening significantly reduced the age at the time of diagnosis (6.9 months vs 15.4 months) as well as the age at the time of the first hearing aid fitting (9.3 months vs 17 months) and age at the time of cochlear implantation (26 months vs 32 months). Children from the screening program had better results in speech audiometry (95% discrimination vs 84%), monosyllabic tests (62% vs 34%), CAP (level 6 vs level 5), evaluation of spontaneous speech (level 6 vs level 5), and intelligibility of speech (level 5 vs level 3.5). According to the statistical evaluation (Fisher's test) the functional results did not show significant difference.     

人工耳蜗植入后对侧耳是否联合使用助听器声调识别的对比研究

目的 探讨人工耳蜗植入后对侧耳联合使用助听器对声调识别的影响;同时探讨人工耳蜗开机时间、康复训练时间、听障儿童的学习能力等因素对声调识别的影响。 方法 选择3~7岁的人工耳蜗植入儿童27例,采用《言语听觉反应评估》(EARS)中的“封闭式声调测试”作为测试材料,分别单独使用人工耳蜗(CI)和在人工耳蜗对侧耳联合使用助听器(CIHA)在安静和噪声两种环境下进行声调识别的测试,使用SPSS 17.0对测试结果进行统计学分析。 结果 无论在安静环境还是噪声环境下,CIHA的声调测试成绩均优于CI,此优势在噪声环境下更明显;人工耳蜗开机时间、康复训练时间较长者声调测试成绩均优于较短者;听障儿童的希-内学习能力测试结果学习能力DIQ≥100与DIQ<100者声调测试成绩差异无统计学意义。 结论 建议听障儿童人工耳蜗植入后对侧耳联合使用助听器,但助听器需要优化和调整。     

Comparison of speech perception between monaural and binaural hearing in cochlear implant patients

Objective To assess the advantages of binaural hearing for cochlear implant (CI) users using a hearing aid (HA) for the contralateral ear.

Material and Methods The subjects comprised 3 males and 3 females (age range 48–84 years). All of them had been using a CI and HA for >6 months. Their speech perception was examined in quiet using monosyllables and Japanese Hearing in Noise Test (J-HINT) sentences. Speech perception in noise was examined using J-HINT sentences. Late cortical waves were measured while subjects listened to 1 kHz frequent and 2 kHz target tone stimuli. The latency of the event-related potential (P300) wave was compared for monaural and binaural hearing conditions.

Results Three subjects showed significantly better results for binaural than monaural (CI alone) hearing for monosyllables and HINT sentences (p<0.05; paired t-test). Subjects with better speech perception had been using an HA for longer than those with poor performance (18.3 vs 4.0 years). The overall average score was better for binaural than monaural hearing in the speech perception test under quiet and noisy conditions. Comparison of the latency of the P300 wave under monaural and binaural hearing conditions showed a significantly shorter latency for the latter (p=0.02; paired t-test).

Conclusion Although the use of an HA alone showed marginal benefit for CI users, binaural hearing (CI + HA) resulted in a significant improvement in speech perception under various circumstances.