Cochlear™Nucleus®声音处理器30年进展
2016-04-12AnneBeiterEstiNelCochlear有限公司译者孙雯审校张华译者单位首都医科大学附属北京同仁医院耳鼻咽喉头颈外科北京市耳鼻咽喉科研究所耳鼻咽喉头颈科学教育部重点实验室首都医科大学北京100005
Anne L.Beiter* Esti Nel Cochlear有限公司译者:孙雯 审校:张华译者单位:首都医科大学附属北京同仁医院耳鼻咽喉头颈外科北京市耳鼻咽喉科研究所耳鼻咽喉头颈科学教育部重点实验室(首都医科大学)(北京100005)
Cochlear™Nucleus®声音处理器30年进展
Anne L.Beiter*Esti Nel Cochlear有限公司
译者:孙雯审校:张华
译者单位:首都医科大学附属北京同仁医院耳鼻咽喉头颈外科
北京市耳鼻咽喉科研究所耳鼻咽喉头颈科学教育部重点实验室(首都医科大学)(北京100005)
【摘要】目的回顾对于耳蜗植入者有显著效果的Nucleus®声音处理器的30年进展。
【关键词】人工耳蜗植入;声音处理器;智能声;环境分类器;无线附件
Declaration of interest:These developments were funded by Cochlear Limited,the manufacturer of Nucleus implant systems.
30年前,世界上第一例多导人工耳蜗植入手术在澳大利亚应用于一位来自墨尔本的失聪患者。迄今为止,越来越多的聋病患者接受人工耳蜗植入术,效果显著且生活质量明显提高。目前全球Nucleus®植入者已经超过400,000人。Graeme Clark和他的研发团队创建了Cochlear公司,首次将多导人工耳蜗引入市场。30多年来,开拓精神成为Cochlear成功的关键。团队不断研发更加小巧、先进及便于使用的声音处理器。从Cochlear最早的体配式处理器到世界上第一个耳背式处理器,再到现在的Nucleus®6处理器,Cochlear一直秉承着这种开拓精神。Cochle⁃ar第九代声音处理器,Nucleus 6是目前市场上体积最小、最先进的产品,在助听效果、无线连接及生活方式等方面都有很大突破。
声音处理器根据特定的指令和算法处理来自麦克风的声信号,对声信号进行一定形式的编码后,通过射频载波透过皮肤传递给人工耳蜗的接收刺激器。接受刺激器将信息数据转换为双相电脉冲送入人工耳蜗电极。Cochlear处理器使用经皮耦合,接收刺激器的能量和编码的数据都通过射频链接进行传递。
最早的处理器电路主要是模拟电路,少有数字电路,不能处理大量数据。因此,诸如佩戴式声音处理器(wearable speech processor,WSP)和迷你声音处理器(mini speech processor,MSP)这类处理器只可编码和传递基本声学参数,例如信号的幅度、基频估值、第一和第二共振峰以及使用MSP时的一些更高频能量等[1,2]。现在的处理器包含低功耗、定制的数字信号处理(digital signal processing,DSP)芯片,能够快速执行复杂的数学计算。这些处理器使用复杂的言语编码策略,例如谱峰(spectral peak,SPEAK),连续相间采样(continuous interleaved sampling,CIS)和高级结合编码(advanced combination encoder,ACE)策略。这些编码策略能够高速处理数据,并可将信息传递给耳蜗内更多的电极[2,3]。工程师已发明出新的DSP算法,能够结合多个麦克风的输出,提高在复杂环境下的聆听效果。一些算法专为去除声信号中的噪声。下文将就声音处理技术的提高对人工耳蜗植入效果的改善进行讨论[4~6]。
1 植入后效果的改善
科技的进步与听觉植入适应证的变化使得人工耳蜗的效果得到提高。效果的改善拓宽了候选者的选择范围,而随着适用范围的拓宽,植入效果进一步提升。适应证扩展后出现了新的治疗方法,如中耳和骨导植入,声电联合刺激和直接声刺激人工耳蜗植入(图1)。为应对新需求,须进一步改进声音处理器技术。例如,因效果较好,双侧植入更加普遍。目前全球大概有33,000位双侧Nucleus植入者,其中约60%为儿童和青少年。有文献表明双耳在定位、噪声下聆听、音质等方面优于单耳[7~15]。
图1 适用于不同听力损失和适应证的听力解决方案(中重度感音神经性听力损失或者传导性/混合性听力损失可以选择中耳植入。重度极重度感音神经性听力损失,低频有残余听力可选择声电联合人工耳蜗植入。重度或者极重度感音神经性听力损失及极重度传导性或混合性听力损失可选择人工耳蜗植入。中度混合性或传导性听力损失可选择骨导植入。重度混合性或传导性听力损失可选择直接声学人工耳蜗植入装置。)Figure 1 Available treatment options related to degree of hearing loss as well as expanded indications
由于适应证拓宽,越来越多有残余听力的听障者接受人工耳蜗植入。现有技术可有效利用术后残余听力。Cochlear™Hybrid™Hearing声音处理器利用声学放大改善低频听力,而传统助听设备不能处理的高频听力可以通过人工耳蜗恢复(图2,图3)。有文献表明声刺激对于使用电刺激接受信息的植入者可以提供重要的附加信息[9,10,16~23]。每个Nucleus 6处理器均配备有Hybrid功能。
图2 Hybrid Hearing使用声学放大来改善低频的听力,通过人工耳蜗的电刺激恢复高频听力。每个Nucleus 6都配备了Hybrid功能。Figure 2 Hybrid Hearing uses acoustic amplification to improve low-frequency hearing and electrical stimulation through the cochlear implant to restore high-frequency hearing.
图3 左图显示受试者术前在Cochlear Nucleus Hybrid System FDA临床实验中声场下佩戴助听器的平均听阈和植入术后声场下的平均听阈(耳蜗植入术后较好地保留了低频的听力,高频听力得到明显改善,而助听器不能有效放大高频)。右图显示各个受试者对侧耳的阈值(均为高频陡降型)。Figure3 The left panel illustrates mean pre-operative aided sound field thresholds and mean Hybrid sound field thresholds at initial activation for subjects in the Cochlear Nucleus Hybrid System FDA clinical trial.The right panel illustrates individual subject hearing thresholds in the contralateral ear.
随着基本声音编码的进步,聆听效果得到了提高,其中前端输入信号处理方法扮演着越来越重要的角色。2005年Cochlear引进了Freedom®声音处理器的SmartSound®技术,将方向性(前置)麦克风和全向性(后置)麦克风结合,创建了自适应方向性技术(beamformer),推动了第一个商业自适应方向性技术的问世[3,24]。智能声升级为智能声2,促进了不同聆听环境下不同输入信号的处理方法的发展,并设有4种预先设定的使用环境,即日常安静环境、噪声环境、专注和音乐环境,植入者需手动选择和更换程序[25]。现在Nucleus 6处理器是第三代智能声——SmartSound®iQ,使智能声完全自动化。使用环境分类器(scene classifier,SCAN),Nucleus 6处理器可自动选择最适应当下聆听环境的输入信号处理方法。SSiQ有两类程序:第一种为默认SCAN程序,能够分析植入者的听觉环境,自动选择输入信号处理方式和麦克风的方向性,提供最佳聆听效果和舒适度。第二种为定制程序,根据个人听觉偏好和聆听要求特别定制[6,26]。
Mauger[6]等认为SCAN中自适应方向性有利于噪声环境下聆听。他们进行了一项实验,将植入者分为三组,第一组使用SCAN声音处理器,第二组使用没有任何输入信号处理程序的处理器,第三组使用智能声2。三组分别进行相同的言语识别阈测试,发现第一组植入者言语识别阈平均提高3.8 dB(图4左图)。当所有言语声和噪声都来自前方时,植入者聆听非常困难。此时使用SCAN降噪算法(SNR-NR)的受试者,言语识别率比没有任何输入信号处理的受试者平均提高2.3 dB。使用Nucleus 6和带有SNR-NR的SCAN与Nucleus 5相比,受试者言语识别阈平均提高1.7 dB(图4右图)。
图4 .左图为4人交谈言语噪声测试,言语声来自前方,噪声来自侧面和后方,使用SCAN(黄色,-3.86 dB)与不使用智能声(灰色,-0.04 dB)或使用智能声2(蓝色,-0.37 dB)的言语识别阈对比(使用SCAN比不使用智能声平均改善3.8 dB)。右图为在言语加权噪声下使用Nucleus SNR-NR算法(黄色,-2.88 dB)与不使用智能声(灰色,-0.58 dB)或使用智能声2(蓝色,-1.33 dB)平均言语识别阈的对比(使用降噪算法比不使用智能声平均改善约2.3 dB)和使用Nucleus 6(黄色,-2.9 dB)与使用Nucleus 5(灰色,-1.2dB)言语识别阈的对比(平均改善1.7dB)。Figure 4.The left panel illustrates the mean performance improvements with Nucleus 6 using SCAN(SmartSound iQ) in 4 talker babble noise when speech comes from the front and noise from the sides and behind compared to no SmartSound or SmartSound2.The right panel illustrates the mean performance improvements in speech weighted noise using the Nucleus 6 signal-to-noise reduction(SNR-NR) algorithm when speech and noise are co-located compared to no SmartSound or Smart-Sound2.Also illustrated is the mean performance improvement using Nucleus 6 with SNR-NR compared to performance with subjects' Nucleus 5 processor.
最近,Cochlear设计和研发组的听力学家将Nu⁃cleus 6用于Nucleus 22植入者(图5)。结果显示SCAN与Freedom处理器相比,受试者言语识别率在言语加权噪声下提高6 dB,在4人交谈噪声(babble)下提高5 dB[27,28]。
图5 左图为在言语加权噪声下Nucleus 22受试者使用SCAN程序(黄色,-6.9 dB)、使用Freedom处理器(浅灰色,-0.93 dB)、使用不带有SCAN的Nucleus 6处理器(深灰色,-0.17 dB)三者平均提升效果的对比(使用SCAN比使用Freedom处理器平均改善约6 dB)。右图为在4人交谈言语噪声下Nu⁃cleus 22受试者使用SCAN程序(黄色,-1.9 dB)、使用Freedom处理器(浅灰色,3.25 dB)、使用不带有SCAN的Nucleus 6处理器(深灰色,3.1 dB)三者平均提升效果的对比(使用SCAN比使用Freedom处理器平均改善约5 dB)。Figure 5 The left panel illustrates mean performance improvements in speech weight noise for Nucleus 22 subjects using the default SCAN program compared o their Freedom processor and to Nucleus 6 using a program without SCAN.The right panel illustrates mean performance improvements in 4 talker babble noise for Nucleus 22 subjects using the default SCAN program compared to their Freedom processor and to Nucleus 6 using a program without SCAN.
2 无线连接附件增加言语识别率
Cochlear是首家推出无线附件的植入体生产商。以前声音处理器的音频附件需要有线连接,存在一些局限性,并没有在植入者中广泛使用。无线附件的便利性使得越来越多的植入者从中受益。图6展示了一些无线附件包括无线麦克风、TV streamer 和Phone Clip。最近的研究表明与单独使用Nucleus 6相比,使用无线麦克风在噪声下短句识别平均提高8 dB[27,28](图7)。
Nucleus 6是Cochlear第一个有数据记录功能的处理器,能够监测和记录声音处理器和配件的使用情况。临床医生可以根据记录的数据来观察设备的使用模式,给予临床建议,使植入者获得更丰富的听觉体验。
图6 .Cochlear无线附件:无线麦克风,TVStreamer和Phone ClipFigure 6.Cochlear's wireless accessories:Mini Microphone,TV Streamerand Phone Clip.
图7 单独使用Nucleus 6(灰色)和使用Nucleus 6配备无线麦克风(黄色)的BKB短句测试的平均言语识别阈(后者提高了8 dB,而且噪声下改善明显。并在类似于教室的噪声环境下,使用无线麦克风的聆听效果更好。)Figure 7.Mean performance on the Bamford Kowal Bench speech reception threshold test (SRT) in noise using the Nucleus 6 alone and the Nucleus 6 with the Mini Microphone.
3 展望未来
人工耳蜗植入者受益于体积更小巧、设计更加出色的声音处理器。Nucleus 6与Freedom®处理器相比,体积约减小50%,更加隐蔽,佩戴更舒适。其外层为纳米涂层,防水级达IP57,更具可靠性。配备了Cochlear Aqua附件的Nucleus 6防水级别为IP58,解决了植入者无法游泳的问题。
Cochlear植入技术将努力使各种组件小型化,设计能耗更少、体积更小的植入体和声音处理器。未来的人工耳蜗可能有不同电极组和接收刺激器,将电流传送到植入电极,聚集电刺激,增加更多独立通道,提高植入者的言语理解能力[29,30]。新的电极组可进一步减小耳蜗创伤,传递不同的治疗药物以加强神经生长和/或维持残余听力[31~34]。
另外Cochlear公司与人工耳蜗植入和助听器创新研究中心合作,研究全植入式人工耳蜗植入(totally implantable cochlear implant,TIKI)产品[35,36]。在墨尔本人工耳蜗植入临床大学,三个重度到极重度感音神经聋成人患者植入TIKI,无手术和术后并发症。三个受试者通过“隐形听觉”模式或者外部ESPrit 3G声音处理器使用TIKI进行工作。此产品对内部麦克风灵敏度有限制。与使用ESPrit 3G处理器比较,隐形听觉模式下言语可懂度有所下降。另外,身体内部噪声干扰会减少受试者使用隐形听觉模式的时间。故还需进一步研究改善皮下麦克风和信号处理。
30多年来Cochlear不断创新多种声音处理器产品,大大提升言语感知效果,拓宽适应证,满足不同患者需求。植入效果不再是考量产品唯一的指标,植入者的生活方式以及沟通需求也逐渐被重视起来,由此推动了声音处理器设计理念上的变革。Co⁃chlear将关注后续技术的兼容性,并一如既往地坚守“聆听现在,韵律永恒”的承诺。
(The paper was published on the 4th issue of Chinese Journal of Otology)
参考文献
1Clark,G.M.,Tong,Y.C.,Patrick,J.F.,Cochlear Prostheses.Churchill Livingstone,New York,1990,pp.99-124.
2Clark,G.M.,Cochlear Implants:Fundamentals and Applications.Springer-Verlag,New York,2003,pp.454-549.
3Patrick,J.F.,Busby,P.A.,Gibson,P.J.,The development of the Nu⁃cleus Freedom cochlear implant system.Trends Amplif.2006,10,175-200.
4Dawson,P.W.,Mauger,S.J.,Hersbach,A.A.,Clinical evaluation of signal-to-noise ratio-based noise reduction in Nucleus cochlear im⁃plant recipients.Ear Hear.2011,32,382-390.
5Hersbach,A.A.,Arora,K.,Mauger,S.J.,Dawson,P.W.,Combining directional microphone and single-channel noise reduction algo⁃rithms:a clinical evaluation in difficult listening conditions with co⁃chlear implant users.Ear Hear.2012,33,e13-23.
6Mauger,S.J.,Warren,C.D.,Knight,M.R.,Goorevich,M.,Nel,E.,Clinical evaluation of the Nucleus®6 cochlear implant system:per⁃formance improvements with SmartSound iQ.Int.J.Audiol.2014,53,564-576.
7Dunn,C.C.,Tyler,R.S.,Oakley,S.A.,et al.,Comparison of speech recognition and location performance in bilateral and unilateral co⁃chlear implant users matched on duration of deafness and age at im⁃plantation.Ear Hear.2008,29,352-359.
8Litovsky,R.,Parkinson,A.,Arcaroli,J.,Spatial hearing and speech intelligibility in bilateral cochlear implant users.Ear Hear.2009,30,419-431.
9Dunn,C.C.,Noble,W.,Tyler,R.S.,et al.,Bilateral and unilateral cochlear implant users compared on speech perception in noise.Ear Hear.2010,31,296-298.
10Dunn,C.C.,Perreau,A.,Gantz,B.,et al.,Benefits of localizationand speech perception with multiple noise sources in listeners with a short electrode cochlear implant.J.Am.Acad.Audiol.2010,21,44-51.
11Litovsky,R.Y.,Review of recent work on spatial hearing skills in children with bilateral cochlear implants.Cochlear Implant.Int.2011,12(Suppl 1),30-34.
12 Ramsden,J.D.,Gordon,K.,Aschendorff,A.,et al.,European bilat⁃eral pediatric cochlear implant forum consensus statement.Otol.Neurotol.2012,33,561-565.
13Galvin,K.L.,Holland,J.F.,Hughes,K.C.,Longer-term functional outcomes and everyday listening performance for young children through to young adults using bilateral implants.Ear Hear.2013,35,171-182.
14 Hughes,K.C.,Galvin,K.L.,Measuring listening effort expended by adolescents and young adults with unilateral or bilateral cochlear im⁃plants or normal hearing.Cochlear Implant.Int.2013,14,121-129.
15Potts,L.G.,Litovsky,R.Y.,Transitioning from bimodal to bilateral cochlear implant listening:speech recognition and localization in four individuals.J.Am.Acad.Audiol.2014,23,79-92.
16 Gantz,B.J.,Turner,C.,Gfeller,K.E.,et al.,Preservation of hearing in cochlear implant surgery:advantages of combined electrical and acoustical speech processing.Laryngoscope 2005,115,796-802.
17 Dorman,M.F.,Gifford,R.H.,Combining acoustic and electric stim⁃ulation in the service of speech recognition.Int.J.Audiol.2010,49,912-919.
18 Gifford,R.H.,Dorman,M.F.,Skarsynski,H.,et al.,Cochlear implan⁃tation with hearing preservation yields significant benefit for speech recognition in complex listening environments.Ear Hear.2013,34,413-425.
19 Incerti,P.V.,Ching,Y.C.,Cowan,R.,A systematic review of electri⁃cacoustic stimulation:device fitting ranges,outcomes and clinical fit⁃ting practices.Trends Amplif.2013,17,3-26.
20 Lenarz,T.,James,C.,Cuda,D.,et al.,European multi-centre study of the Nucleus Hybrid L-24 cochlear implant.Int.J.Audiol.2013,52,838-848.
21 Gifford,R.H.,Grantham,D.W.,Sheffield,S.W.,et al.,Localization and interaural time difference (ITD) thresholds for cochlear implant recipients with preserved acoustic hearing in the implanted ear.Hear.Res.2014,312,28-37.
22 Jurawitz,M.C.,Buchner,A.,Harpel,T.,et al.,Hearing preservation outcomes with different cochlear implant electrodes:Nucleus™Hy⁃brid®L-24 and Nucleus®Freedom CI422.Audiol.Neurotol.2014,19,293-309.
23 Roland,J.T.,Gantz,B.J.,Waltzman,S.B.,et al.,2015.United States multicenter clinical trial of the Cochlear Nucleus Hybrid implant system.Laryngoscope.http://dx.doi.org/10.1002/lary.25451 pub⁃lished on line,7 July 2015.Copyright©2015 Wiley Periodicals,Inc.,A Wiley Company.
24Spriet,A.,Van Deun,L.,Eftaxiadis,K.,et al.,Speech understand⁃ing in background noise with the two-microphone adaptive beam⁃former BEAM in the Nucleus Freedom cochlear implant system.Ear Hear.2007,28,62-72.
25 Wolfe,J.,Parkinson,A.,Schafer,E.,et al.,Benefit of a commercial⁃ly available cochlear implant processor with dual-microphone beam⁃forming:a multi-center study.Otol.Neurotol.2012,33,553-560.
26 Wolfe,J.,Neumann,S.,Marsh,M.,et al.,August Benefits of adap⁃tive signal processing in a commercially available cochlear implant sound processor.Otol.Neurotol.2015,36 (7):1181-1190.
27 Cochlear Limited,2015a.Acceptance of Nucleus 6 SSIQ in a Group of Nucleus®22 Series Cochlear Implant Recipients Study Report.
28 Cochlear Limited,2015b.Use of Cochlear™Wireless Accessories with Nucleus®6 Sound Processors Study Report.
29 Bierer,J.A.,Probing the electrodeeneuron interface with focused co⁃chlear implant stimulation.Trends Amplif.2010,14,84-95.
30 30.Long,C.J.,Holden,T.A.,McClelland,G.H.,et al.,Apr 2014.Ex⁃amining the electro-neural interface of cochlear implant users using psychophysics,CT scans,and speech understanding.J Assoc Res.Otolaryngol.http://dx.doi.org/10.1007/s10162-013-0437-5.Asso⁃ciation for Research in Otolaryngology Published online 30 January 2014.15 (2):293-304.
31 Wilson,B.S.,Dorman,M.F.,2008.Cochlear implants:a remarkable past and a brilliant future.Hear.Res.242,3-21.
32Jolly,C.,Garnham,C.,Mirzadeh,H.,Truy,E.,Martini,A.,Kiefer,J.,Braun,S.,Electrode features for hearing preservation and drug delivery strategies.Adv.Otorhinolaryngol.2010,67,28-42.
33 Shepherd,R.K.,Rescuing the cochlea:the challenges.ENT Audiol.News 2011,19 (6):49-52.
34 Astolfi,L.,Guaran,V.,Marchetti,N.,Olivetto,E.,Simoni,E.,Cavazzini,A.,Jolly,C.,Martini,A.,Cochlear implants and drug de⁃livery:in vitro evaluation of dexamethasone release.J.Biomed.Ma⁃ter.Res.B Appl.Biomater.2014,102,267-273.
35 Briggs,R.J.S.,Eder,H.C.,Seligman,P.M.,Cowan,R.S.,Plant,K.L.,Dalton,J.,Money,B.K.,Patrick,J.F.,Initial clinical experience with a totally implantable cochlear implant research device.Otol.Neuro.2008,29,114-119.
36 Briggs,R.J.S.,Future technology in cochlear implants:assessing the benefit.Cochlear Implant.Int.2011,12,S22-S25.
·技术与方法·
The history of CochlearTMNucleus®sound processor upgrades:30 years and counting
Anne L.Beiter*,Esti Nel
Cochlear Limited
Translator:SUN Wen ,Review :ZHANG Hua
The translator unit:Beijing tongren hospital affiliated to the capital university of medical sciences,otolaryngology head and neck surgery
Beijing institute of otolaryngology department Key laboratory of otolaryngology head and neck science the ministry of education to the capital university of medical sciences,100005 (Beijing)
【Abstract】Objective To review developments in sound processors over the past 30 years that have resulted in significant improvements in outcomes for Nucleus®recipients.
【Keywords】Cochlear implant; Sound processor; SmartSound; SCAN; Wireless accessories
通讯作者:Anne L.Beiter,Email:abeiter@cochlear.com
作者简介:Anne L.Beiter,硕士,研究方向:人工耳蜗
DOI:10.3969/j.issn.1672-2922.2016.01.025
【中图分类号】R764
【文献标识码】A
【文章编号】1672-2922(2016)01-115-5