16例Nucleus 24导弯电极人工耳蜗植入体会

目的 通过总结16例Nucleus24导弯电极人工耳蜗植入体会,比较其与24导直电极手术方法的不同,就其临床手术植入中有关情况做出评价。方法 所有患者均于耳后切口经面神经隐窝入路植入电极,术中均进行电极阻抗测试和听神经遥测反应(NRT)测试。结果 所有患者电极全部顺利植入蜗内,阻抗测试均正常。术中均引出满意NRT反应。结论 Nucleus24导弯电极人工耳蜗由于其独特的设计和性能,使得人工耳蜗植入手术适用年龄更小,手术更安全,操作更简便、更容易。术后并发症更少。     

电诱发听性脑干反应和电诱发镫骨肌反射阈值在内耳畸形儿童人工耳蜗植入术后调机中的运用

目的　探讨内耳畸形小儿人工耳蜗植入手术后,植入体电诱发听性脑干反应（electrically evoked auditory brainstem responses,EABR）、电诱发镫骨肌反射阈值（electrically evoked stapedius reflex threshold,ESRT）的变化特点及规律,以指导术后设备调试。方法　将88例澳大利亚Cochlear Nucleus24型人工耳蜗植入手术患儿分为耳蜗形态正常组与内耳畸形组,测试手术后1年内不同时期EABR和ESRT值,术后1年运用行为测试法检测主观阈值（T值）和最大舒适阈（C值）,分析特点及变化规律。结果  内耳畸形组患儿术后不同时期EABR和ESRT阈值较正常组高（P＜0.05）,两组EABR和ESRT阈值变化趋势相同,总的趋势是低频值较低,高频值较高,术后1年EABR和ESRT阈值逐渐增高;两组EABR与T值显著相关,ESRT与C值显著相关。结论　内耳畸形组人工耳蜗植入手术后EABR和ESRT阈值变化规律及特点与正常组患儿相同,阈值可用于指导内耳畸形人工耳蜗植入者手术后设备的调试。     

人工耳蜗植入术后神经反应遥测阈值与行为阈值及舒适阈的比较

目的 通过对人工耳蜗植入术后不同患者神经反应遥测（neural response telemetr,NRT)阈值与行为反应阈值（T-level,T级）及舒适阈（C-level,C级）的比较，试图为小年龄或不能给予准确反应的患者客观估算人工耳蜗植入术后行为反应T、C级提供依据。方法 受试对象为使用Nucleus CI24M型多导人工耳蜗系统的70例患者。共测试329个电极。测试软件为NRT2.04版本。NRT阈值的测试采用单极刺激方式（monopolar stimulation mode)，分别测试每一位患者的第3、5、10、15、20号电极。T级和C级的测试均于NRT测试同日进行。结果 70例患者的329个电极的NRT波形检出率为92.7%。同一患者不同编号电极的NRT反应幅值和阈值及不同患者同一编号电极的NRT反应幅值和阈值均存在差异。NRT阈值的均值介于行为反应T级和C级的均值之间。NRT阈值及T、C级的数值自蜗底至蜗顶呈下降趋势。结论 NRT阈值、T级和C级的个体差异较大，尚不能根据NRT阈值对T级和C级进行准确的判断。但NRT技术可为不能配合术后调试的儿童患者的行为反应T、C级的估算提供客观的方法。NRT这一新技术仍有待于改进。     

儿童人工耳蜗植入术后电诱发复合动作电位分析

目的 应用神经反应遥测(NRT)技术,观察人工耳蜗植入后不同时间段的电诱发复合动作电位(ECAP)阈值变化,探讨其对人工耳蜗术后调机的指导意义。方法 对33例使用Nucleus CI24R(CA)型人工耳蜗植入的患儿,于术中及术后1、1.5、2、4、6个月进行ECAP 阈值测试,统计分析其变化规律。结果 33例165个电极的波形检出率为93.3%。电极1、7、11、17、22的术中ECAP阈值与术后30d开机时的ECAP阈值的差异有统计学意义。同一测试电极,随术后开机时间的增长,ECAP阈值呈逐渐增加的趋势。经单因素方差分析,术后不同测试时间ECAP阈值差异有统计学意义。结论 ECAP检出率高,术中可用于检测神经反应;术后可协助估算患者的行为反应T、C级,指导调机,尤其对儿童患者更为重要。     

Nucleus人工耳蜗弯电极和直电极植入后的心理物理指标比较

目的对比Nucleus CI 24导Contour弯电极与Nucleus CI 24导直电极植入后的电阻阻抗、刺激阈值和舒适阈。方法植入澳大利亚NucleuS人工耳蜗的患者分为2组,1组（19例）植入Nucleus CI 24导Contour电极阵列（弯电极）,另1组（11例）植入CI 24M电极阵列（直电极）。所有患者耳蜗植入术后15天开机调试,并于开机时及开机后1周、1月、3月分别记录各电极的电阻、刺激闽值和最大舒适阈。结果开机后由于Nucleus 24直电极的刺激阈值呈上升趋势,3月和6月时弯电极的阈值明显低于直电极阈值,且差异有统计学意义（P〈0．05）。开机1周、1月和6月2组的舒适阈接近。开机后弯电极和直电极的电阻值接近。结论Nucleus CI 24导Contour弯电极的刺激阈值稳定,刺激阈和舒适阈之间动态范围较宽。     

内耳畸形小儿人工耳蜗植入术后电极阻抗测试的研究

目的探讨内耳畸形小儿人工耳蜗植入手术后,植入体电极阻抗值的变化特点及规律。方法对36例澳大利亚Cochlear Nucleus 24型内耳畸形小儿人工耳蜗植入手术患儿,测试手术中及手术后1年阻抗值,并分析其特点及变化规律。结果患儿术中及开机后1年内高中低频段电极阻抗值变化趋势相同。电极阻抗值术中自开机显著增大,术中阻抗值最低,开机达到最大值,其后呈下降趋势,于开机3月后趋于平稳。结论内耳畸形小儿人工耳蜗植入手术后电极阻抗值开机3个月内变化明显,故需多次调机,以使患者语言感知达到最佳状态。     

人工耳蜗植入电极插入技巧对蜗内电极位置的影响

目的　观察不同手术技巧对多导人工耳蜗植入术后蜗内电极位置的影响。方法　采用澳大利亚Nu cleus 2 4M (直电极 )、Nucleus 2 4Contour(弯电极 )以及不同的手术技巧 ,术后以改良斯氏位X线拍片 ,测量、比较蜗内电极插入的深度。结果　 59例人工耳蜗植入病例中 ,3 2例Nucleus 2 4M型人工耳蜗常规手术的电极X片显示电极在平面图上的深度为 2 68°～ 3 53° ,平均 2 78.6° ;15例Nucleus 2 4M型人工耳蜗采用改进的电极插入方法 ,术后耳蜗电极X片在平面上显示弯成 3 60°～ 445° ,平均深度 3 91.7° ;12例Nucleus 2 4Contour型人工耳蜗植入采用标准术式 ,术后蜗内电极X片在平面上显示电极弯成 3 80～ 455° ,平均 42 3°。结论　澳大利亚Nucleus 2 4M型人工耳蜗通过改良的手术技巧可使电极插入的深度更大 ,部分病例可与弯电极相似 ,Nucleus 2 4Contour型人工耳蜗的电极则更靠近蜗轴     

多导人工耳蜗植入后电极阻抗的初步研究

目的研究多导人工耳蜗植入后电极阻抗变化的特点,对比直电极和弯电极的阻抗差异,为人工耳蜗植入术后的调试提供参考。方法在Nucleus多导人工耳蜗编程调试界面上,应用R126V1.3和NRTV3.0软件,测试11例语前聋儿童在不同时期的阻抗值,并进行分析比较。结果CI24M和CI24Rcontour两种植入体阻抗随时间变化的基本规律是:术中较低,开机时最高,以后随时间推移逐渐降低。CI24Rcontour阻抗高于CI24M。结论人工耳蜗植入体阻抗开机后随时间推移而逐渐降低,新型CI24Rcontour植入体与CI24M相比,其阻抗值在术中至开机后3周内明显要高。     

高频电诱发镫骨肌反射测试在人工耳蜗调试中的应用

目的探讨人工耳蜗术后高频(1000 Hz)探测音记录的电诱发镫骨肌反射(electrically evoked stapedius reflex,ESR)测试的特性及其阈值(electrically evoked stapedius reflex threshlod,ESRT)与最大舒适阈值(most comfortable level,C值)之间的关系。方法选取植入诺尔康CS-10A型人工耳蜗的患者26例,对受试者进行高频(1000 Hz)探测音记录的ESR测试,测试电极为2号、7号、12号、17号、23号,获取相应的ESRT,并记录常用程序中相应电极的C值。对5个电极间的ESRT进行重复测量方差分析,对ESRT和C值进行相关性和线性回归分析。结果26名受试者的120个电极可引出ESR,总引出率为92.3%;5个电极间的ESRT差异均有统计学意义(P<0.05),从蜗顶至蜗底呈上升趋势;5个电极的ESRT与C值均极显著相关(P<0.01)。结论高频(1000 Hz)探测音记录的ESRT可指导耳蜗和听神经形态正常及无其他植入禁忌症的诺尔康人工耳蜗植入患儿术后C值的调试。     

人工耳蜗植入术后神经反应遥测阈值与行为阈值及舒适阈的比较

目的　通过对人工耳蜗植入术后不同患者神经反应遥测 (neuralresponsetelemetry,NRT)阈值与行为反应阈值 (T level,T级 )及舒适阈 (C level,C级 )的比较 ,试图为小年龄或不能给予准确反应的患者客观估算人工耳蜗植入术后行为反应T、C级提供依据。方法　受试对象为使用NucleusCI2 4M型多导人工耳蜗系统的 70例患者。共测试 3 2 9个电极。测试软件为NRT2 0 4版本。NRT阈值的测试采用单极刺激方式 (monopolarstimulationmode) ,分别测试每一位患者的第 3、5、10、15、2 0号电极。T级和C级的测试均于NRT测试同日进行。结果　 70例患者的 3 2 9个电极的NRT波形检出率为 92 7%。同一患者不同编号电极的NRT反应幅值和阈值及不同患者同一编号电极的NRT反应幅值和阈值均存在差异。NRT阈值的均值介于行为反应T级和C级的均值之间。NRT阈值及T、C级的数值自蜗底至蜗顶呈下降趋势。结论　NRT阈值、T级和C级的个体差异较大 ,尚不能根据NRT阈值对T级和C级进行准确的判断。但NRT技术可为不能配合术后调试的儿童患者的行为反应T、C级的估算提供客观的方法。NRT这一新技术仍有待于改进     

人工耳蜗植入术后电极阻抗特性分析

目的对使用人工耳蜗系统患者的电极阻抗数值进行分析,总结电极阻抗的变化规律,为临床制定合理的术后调试计划提供依据。方法对152位使用澳大利亚Cochlear Nucleus24M型人工耳蜗系统的患者于术后4周左右安装体外设备并进行测试,使用澳大利亚Cochlear公司提供的R116或R126软件进行电极阻抗测试。结果患者电极阻抗数值自术中至术后开机时呈显著增加的趋势,在开机时达到最大,其后随开机时间的增长显著降低,至开机3个月后趋于稳定,不同部位的电极显示了相同的变化趋势。结论电极阻抗数值随术后使用时间及电极部位的变化而变化。在开机3个月内需多次进行调试,从而为患者提供最适合的程序,使患者的言语感知达到最佳状态。     

Changes over time in electrical stimulation levels and electrode impedance values in children using the Nucleus 24M cochlear implant

OBJECTIVE: The present study was designed to evaluate changes in psycho-electric parameters, i.e. threshold levels, comfortable levels, dynamic range, and electrode impedance values during the 1st year post-implantation, in children using the Nucleus 24M cochlear implant system. METHODS: The maps of 25 pre-lingual children programmed with ACE strategy in Monopolar 1 + 2 mode were examined at five time points: connection, 1, 3, 6, and 12 months post-initial stimulation. Maps and electrode impedance values were analyzed according to three cochlear segments: basal, medial, and apical. RESULTS: Significant elevations of thresholds, comfortable levels, and dynamic range were found during the first few months of implant use. Specifically, threshold increased and dynamic range widened until the 3 months visit, whereas comfortable levels continued to increase until the 6 months visit, thereafter levels stabilized. Electrode impedance values decreased significantly from connection to the 1-month visit thereafter a stabilization of values was evident. In addition, thresholds and comfortable levels were found to be significantly lower in the apical segment, whereas dynamic range and electrode impedance values did not differ among the cochlear segments. CONCLUSIONS: Significant changes in psycho-electric parameters and electrode impedance values were evident during the first 6 months of implant use. Given the important role of an optimal map for speech perception, frequent programming sessions during the first few months of implant use are essential.     

Long-term electrode impedance changes and failure prevalence in cochlear implants

Objective: This study assessed the prevalence of electrode failures and electrode impedance measures in Nucleus cochlear implants around initial activation (an average of 16 days after surgery) and after 8 to 12 years of device use. Design: Retrospective data from the Melbourne Cochlear Implant Clinic was collated and analysed. Study sample: Included in this study were 232 adults, all of whom were implanted at the clinic between March 1998 and August 2005. Results: Overall 0.5% of electrodes failed over the entire test period, with 5.6% of devices showing one or more electrode failure. The majority of these failures were recorded by initial activation. The numbers of electrode failures have decreased over time with array type, such that no failures were recorded with the currently available Contour Advance array. Array type was shown to affect electrode impedance at both time points, with the Contour and Contour Advance arrays having significantly higher absolute values than the Banded array. However, the Banded array had significantly higher area-normalized impedances at initial and final measures than the Contour and Contour Advance array. Conclusions: A relatively low incidence of electrode failures were recorded for the Nucleus devices of these recipients. Electrode impedance dropped for all array types after 8 to 12 years of device use.     

Stability of the cochlear implant array in children

Objective: To determine cochlear implant electrode stability in the young patient. Electrode migration due to future skull growth was a concern that led to prohibiting implantation in children less than 2 years of age. Recently, the high level of performance achieved by young implantees has led to a re-evaluation of this lower age limit, requiring an assessment of the effects of skull growth over time. Study Design: Prospective radiographic analysis of electrode position of cochlear implants in young children. Methods: Twenty-seven children implanted with the Nucleus (Cochlear Corp., Denver, CO) or Clarion (Advanced Bionics Inc., Sylmar, CA) multichannel cochlear prostheses were subjects for this study. Follow-up radiographic studies were obtained for a period of 1 month to 5 years after implantation. The age at time of implantation ranged from 14 months to 5 years. An intraoperative modified Stenver's view plain radiograph was obtained as a baseline. After implantation, on a yearly basis transorbital Stenver's and base views were obtained for comparative purposes. Additional radiographs were obtained whenever a change in performance or electrode map caused suspicion for extrusion. Electrode position was determined using a computer graphics enhancement technique whereby image contrast filters enhanced the visibility of the electrode array and surrounding bony structures. Results: An analysis of the data revealed no migration of the electrode array over time. Conclusions: The confirmation of the stability of the electrode array alleviates the concern of the effects of skull growth on cochlear implantation in young children.     

Electrode impedance changes over time in MED El cochlear implant children recipients: Relation to stimulation levels and behavioral measures

Objective: Electrode impedance measures resistance encountered by electric current passing through wires, electrodes and biological tissue. This study was designed mainly to evaluate changes in electrode impedance values and psycho-electric parameters changes (i.e. threshold levels, comfortable levels, and dynamic range) in cochlear implant patients over time.

Methods: It was a prospective study encompassing 20 patients implanted by MED-EL device programd using behavioral programs. Electrical stimulation levels and electrode impedance values were examined at 0, 1, 3 and 6 months after the first fitting session.

Results: Electrode impedance values were reduced from the time of activation to the 6 months visit. Most comfortable levels increased and dynamic range widened until the 6 months visit. There was an inverse correlation between impedance values and most comfortable level as well as dynamic range, over time.

Conclusion: Frequent monitoring of electrode impedance (for device and electrodes problems) and electric stimulation levels (for better performance, mapping and habituation) during the first 6 months of implant use is recommended.     

Intra- and postoperative electrode impedance of the straight and Contour arrays of the Nucleus 24 cochlear implant: relation to T and C levels

The objective of this study was to investigate electrode impedance in cochlear implant recipients in relation to electrically evoked stapedius reflex measurements during surgery, and to electrode design, stimulation mode, and T and C levels over a nine month period after surgery. Seventy-five implant recipients, implanted with a Nucleus straight electrode array or a Contour array, were included. The results show that: (1) during surgery electrode impedance decreases markedly after electrically evoked stapedius reflex measurements, (2) after surgery, during the period without stimulation until speech processor switch-on, impedance increases, (3) after processor switch-on impedance decreases. The lower impedance values after a period of stimulation are found at the higher T and C levels. Impedances of the straight array electrodes are lower than those of the Contour array. The difference corresponds mainly to their respective surface areas. In addition, the straight array shows a larger increase of impedance in the apical direction than the Contour array, probably because of the larger fluid environment around the basal electrodes of the straight array.     

Nucleus24M型人工耳蜗植入后电极阻抗的变化

目的：研究人工耳蜗植入后电极阻抗的变化规律，以便确定术后进行映射调图的时间表。方法：对16例植入Nucleus CI24M型人工耳蜗患者，于术中及术后1、1．5、2、4、6个月进行电极阻抗测试，统计分析电极阻抗的变化规律。结果：患者电极阻抗在术中检测时最低，开机时最高，以后若干次随访时，阻抗逐渐下降，并在2～4个月左右趋于稳定。结论：电极阻抗的稳定提示耳蜗内生物组织的病理过程渐趋稳定；对心理物理测试配合良好的患者，术后只进行2～4个月左右的映射调图即可。     

儿童人工耳蜗植入术后神经反应遥测阈值的变化

目的:通过对儿童患者术后神经反应遥测 (NRT) 阈值的分析,总结其变化规律,为儿童人工耳蜗植入术后调试提供帮助.方法:测试40例接受Nucleus CI24R 型多导人工耳蜗单侧植入术的患儿.测试使用澳大利亚Cochlear公司提供的便携式调试系统及NRT3.1版本软件.采用削减算法提取NRT反应波形,分别测试每位患者的第1、5、10、15、20号电极,NRT阈值使用NRT软件计算.分别在开机时、开机3、6和12个月时进行测试.结果:在术后同一测试时间,位于耳蜗不同部位电极的NRT阈值存在差异.耳蜗底部和顶部电极的NRT阈值较低,而位于耳蜗中部的电极NRT阈值较高.经单因素方差分析,不同部位NRT阈值均差异有统计学意义.同一测试电极,随术后开机时间的增长,NRT阈值呈逐渐增加的趋势.经单因素方差分析,术后不同测试时间NRT阈值均差异有统计学意义.结论:术后开机1年内,NRT阈值呈逐渐增加的趋势.若人工耳蜗植入术后调试需要NRT进行辅助,每次均应测试NRT阈值,以便更准确估算患者的行为反应T、C级,尤其对植入术后1年内的儿童患者更为重要.