Suprathreshold compound action potential amplitude as a measure of auditory function in cochlear implant users

Electrically evoked compound action potential(e CAP) amplitudes elicited at suprathreshold levels were assessed as a measure of the effectiveness of cochlear implant(CI) stimulation. Twenty-one individuals participated; one was excluded due to facial stimulation during e CAP testing. For each participant, e CAPs were elicited with stimulation from seven electrodes near the upper limit of the individual's electrical dynamic range. A reduced-channel CI program was created using those same seven electrodes, and participants performed a vowel discrimination task. Consistent with previous reports, e CAP amplitudes varied across tested electrodes; the profiles were unique to each individual. In 6subjects(30%), e CAP amplitude variability was partially explained by the impedance of the recording electrode. The remaining amplitude variability within subjects, and the variability observed across subjects could not be explained by recording electrode impedance. This implies that other underlying factors, such as variations in neural status across the array, are responsible. Across-site mean e CAP amplitude was significantly correlated with vowel discrimination scores(r^2= 0.56). A single e CAP amplitude measured from the middle of the array was also significantly correlated with vowel discrimination, but the correlation was weaker(r^2= 0.37), though not statistically different from the acrosssite mean. Normalizing each e CAP amplitude by its associated recording electrode impedance did not improve the correlation with vowel discrimination(r^2= 0.52). Further work is needed to assess whether combining e CAP amplitude with other measures of the electrode-neural interface and/or with more central measures of auditory function provides a more complete picture of auditory function in CI recipients.

Clinical application of electrically evoked compound action potentials

ECAPs are the summary of multiple neurons’ spikes which could be recorded by a bidirectional stimulation-recording system via the cochlear implant,with the artifact elimination paradigms of forward-masking subtraction paradigm or alternating polarity paradigm.Three kinds of FDA approved cochlear implants support ECAP testing.This article is to summarize the clinical application of ECAP lest.ECAP test after insertion of electrode during implant operation has been widely used during cochlear implant surgery.In recent years.ECAP thresholds are also used to estimate the T levels and C levels helping programming.However,correlation between ECAP thresholds and psychophysical thresholds is affected by many factors.So far,ECAPs cannot yet be a good indicator of post-operative hearing and speech performance.

不同致聋基因突变的人工耳蜗植入术后患儿皮层诱发电位的研究

目的观察不同致聋基因突变的人工耳蜗植入患儿皮层诱发电位(CAEP)的差异。方法分析郑州大学第一附属医院耳科32例行单侧人工耳蜗植入术(植入型号为澳大利亚CI512)的无残存听力,且SLC26A4基因、GJB2基因或TMPRSS3基因突变患儿的临床资料,分为A、B、C组。于术后1个月/ba1/和/ba4/声刺激下分别行CAEP检测,记录/ba1/和/ba4/声刺激下P1波引出率、潜伏期、振幅。结果/ba1/和/ba4/声刺激下,A、B组引出率差异无统计学意义(P>0.05);A、B组引出率均高于C组,差异有统计学意义(P<0.05)。/ba1/和/ba4/声刺激下,A、B组潜伏期差异无统计学意义(P>0.05);A、B组潜伏期短于C组,差异有统计学意义(P<0.05)。/ba1/和/ba4/声刺激下,A、B、C组振幅比较,差异无统计学意义(P>0.05)。结论SLC26A4基因、GJB2基因突变的CAEP的P1波引出率高于TMPRSS3基因突变,且LC26A4基因、GJB2基因突变的CAEP的P1波潜伏期短于TMPRSS3基因突变。

多种听力学检测方法在未引出听性脑干反应患儿诊断中的价值

目的探讨多种听力学检测方法在听性脑干反应(ABR)最大输出未引出患儿的听力学诊断中的应用价值。方法回顾性分析69例(138耳)ABR最大强度未引出患儿的临床资料,年龄42天到5岁,平均1岁6个月,鼓室导抗图均为A型或正向单峰,声反射均未引出,影像学检查内耳无畸形。69例患儿均进行ABR、耳蜗微音电位(CM)、畸变产物耳声发射(DPOAE)和听性稳态反应(ASSR)测试。结果69例138耳中,8例16耳(11.59%)记录到CM,其中10耳(7.25%)记录到DPOAE,0.5、1、2、4 kHz ASSR反应阈值分别为83.2±13.1、82.9±13.0、75.3±12.4、63.1±9.1 dB nHL,结合其他检查结果诊断为听神经病。余61例(122耳)CM和DPOAE均未引出,0.5、1、2、4 kHz的ASSR引出率分别为82.3%、81.9%、76.9%、60.2%,其中20耳ASSR各频率均未引出,102耳至少一个频率引出,0.5、1、2、4 kHz ASSR反应阈分别为93.2±6.1、99.8±7.0、105.4±5.4、108.2±9.8 dB nHL,诊断为极重度感音神经性聋。结论对于ABR最大输出强度未引出的患儿,CM和/或DPOAE引出且ASSR各频率反应阈低于感音神经性聋患儿,有助于听神经病的诊断;CM和DPOAE均未引出有助于极重度感音神经性聋的诊断,ASSR测试有助于评估其残余听力。

听觉重塑中时间因素对人工耳蜗植入后电诱发中潜伏期反应的影响分析

目的 对影响人工耳蜗植入后电诱发中潜伏期反应(electrically evoked auditory middle latency response,EMLR)的时间因素,包括植入时年龄、植入后时间及现年龄等进行分析研究,探究听觉重塑过程中不同时间因素的影响。方法 对46例2008年~2014年在北京大学第三医院耳鼻咽喉科进行人工耳蜗植入的患者在术后进行EMLR测试。比较语前聋儿童与语后聋成人EMLR的差异,以及语前聋儿童中现年龄、植入时年龄及植入后时间等因素对EMLR的影响。结果 语前聋儿童EMLR各波潜伏期及波间潜伏期普遍较成人组长,各波间幅值普遍较成人组大,其中Po、Na、Pa、Nb及Pb波潜伏期,PoNa、NaPa及PaNb波间潜伏期,PoNa、NaPa、PaNb及NbPb波间幅值均存在统计学差异(P<0.05)。语前聋儿童中,Pa、Nb波潜伏期及NaPa波间期与现年龄及植入后时间存在显著负相关、与植入时年龄存在显著正相关(P<0.05)。结论 EMLR在语前聋儿童与语后聋成人存在较显著差异,对于语前聋儿童,较大的年龄、较长的植入时间、较小的植入年龄对应更为成熟的EMLR波形,提示上述因素在听觉重塑过程中的重要性。

特殊病例的人工耳蜗植入

从20世纪80年代起,多通道人工耳蜗逐渐进入临床应用,人工耳蜗植入进入了成熟的临床应用阶段。对于常规人工耳蜗植入,手术难度较低,术后效果较为确定。对于特殊病例的人工耳蜗植入,手术风险大、疗效存在不确定性。特殊病例的人工耳蜗植入包括内耳畸形、听神经发育异常、中耳炎和中耳胆脂瘤、耳蜗骨化、单侧聋和非对称性聋等疾病的人工耳蜗植入与再植入等。本文就上述特殊病例人工耳蜗植入涉及的相关问题进行阐述。

人工耳蜗声场听觉皮层诱发电位反应阈和行为测听助听听阈相关性研究

目的研究人工耳蜗植入(CI)后声场短纯音听觉皮层诱发电位(CAEP)反应阈与声场行为测听助听听阈相关性,为无法主观配合声场行为测听的CI患者快速高效的评估提供参考依据。方法募集22名(22耳)CI儿童,对同组使用短纯音在0.5、1、2、4 kHz进行声场CAEP P1波反应阈及声场行为测听并进行相关性分析。结果CI后儿童在0.5、1、2、4 kHz声场短纯音CAEP P1反应阈与声场行为测听助听听阈在对应频率的相关性系数r分别为0.567、0.670、0.627及0.762(P<0.05);人工耳蜗声场短纯音CAEP P1反应阈与声场行为测听阈值显著相关,差值在5~8 dB之间。结论声场短纯音CAEP可用于无法主观配合声场行为测听患者的效果评估,对人工耳蜗临床调试工作提供参考依据。

The Impact of Age and Duration of Cochlear Implant in a Congenital Deaf Population: An ERP Study

Objective: It is well known that patients with Cochlear Implant (CI) have a large inter-individual variability in linguistic and auditory performances. This can be related to individual auditory processing abilities and integrity of auditory system from auditory nerve to cerebral cortex. P300 can be used for the evaluation of central auditory functions in people with hearing loss and CI. No studies considered the P300 in the population of prelingually deafened adults that underwent CI in old age. The aim of this study is to assess Event Related Potential (ERP) in patients with congenital profound hearing loss with early or late implantation and evaluate these results respect to an age-matched normal hearing group. Methods: ERPs (N100, N200 and P300) and auditory benefit testing (pure tone average and speech audiometric test) and auditory perception testing (Categories of Auditory Performance—CAP) were evaluated in all subjects with their device. Results: All mean latencies (N100, N200 and P300) were found greater in patients group compared to control group. When analyzing all measures in patient group, we did not find any significant differences according to age of implant while significant difference (p > 0.05) in N100 amplitude (p = 0.045) and P300 latency (p = 0.035) were found according to time of CI use. A linear correlation between N200 and P300 latency in control and patients groups was found. Conclusion: In summary, ERPs analysis in the evaluation of CI showed a great importance of long use of the device in addiction to an early time of implant.

听觉皮层诱发电位在低龄人工耳蜗植入患儿中的应用

目的探究听觉皮层诱发电位在低龄人工耳蜗植入儿童中的应用价值。方法52例低龄人工耳蜗植入术后患儿,采用主观听觉言语能力评估量表,听觉行为分级量表(Categories of auditory performance,CAP)和言语可懂度分级量表(Speech intelligibility rating scale,SIR)和客观电生理检测[(皮层听觉诱发电位(cortical auditory evoked potential,CAEP)测试中的慢皮层反应P1-N1-P2和失匹配负波(mismatch negativity,MMN)]相结合,进行康复效果的评估,采用SPSS 25.0软件进行统计分析。结果随着听觉年龄的增长,人工耳蜗植入患儿的主观听觉言语能力评估量表分值呈现逐步升高趋势,CAP结果组间有统计学差异(F=22.387,P<0.001),SIR结果组间有统计学差异(F=25.780,P<0.001)。主观量表评估与客观电生理评估存在相关性,CAP结果与CAEP的P1波的阈值具有显著的负相关(r=-0.370,P=0.01),CAP结果与MMN的潜伏期具有显著的负相关(r=-0.309,P=0.029),SIR结果与CAEP的P1波的阈值具有显著的负相关(r=-0.335,P=0.021)。同时采用多因素回归分析探讨康复效果的可能影响因素。结论听觉皮层诱发电位的P1波反应阈值及MMN潜伏期为康复效果评估的独立影响因素。听觉皮层诱发电位可以有效地客观评估低龄人工耳蜗植入患儿的术后康复效果。

皮层听觉诱发电位在人工耳蜗植入中的应用

皮层听觉诱发电位(cortical auditory evoked potential,CAEP)是一种非侵入性脑电测量方式,能够通过波形的阈值、潜伏期与振幅评估听觉皮层的功能。近年来,CAEP的测试方式逐渐成熟,应用更加广泛。在人工耳蜗植入患者中,CAEP能够用于术前、术后听觉及言语能力、双耳听觉、音乐感知以及听觉可塑性的评估。相比较听性脑干反应(auditory brainstem response,ABR)、中潜伏期反应(middle latency response,MLR)等其它听觉诱发电位而言,CAEP潜伏期最长,能够反映完整听觉通路的情况、评价听觉皮层等高级中枢的功能及成熟度,具有独特优势。本文就CAEP在人工耳蜗患者中的研究进展进行综述。

内耳畸形患儿人工耳蜗植入前后前庭诱发肌源性电位变化

目的探讨不同内耳畸形患儿人工耳蜗植入前后前庭诱发肌源性电位(vestibular evoked myogenic potential,VEMP)变化及其与前庭损伤症状的关系。方法2021年1月至6月间先天性重度感音神经性聋患儿29例,其中内耳结构正常12例(24耳),前庭水管扩大4例(8耳),Mondini畸形(耳蜗不全分隔II型合并前庭水管扩大)7例(14耳),共同腔畸形6例(12耳)。分别于术前1天及术后1个月CI关闭时进行颈性前庭诱发肌源性电位(cVEMP)和眼性前庭诱发肌源性电位(oVEMP)测试,术后1周内观察并记录患儿前庭功能损伤症状。结果术前cVEMP、oVEMP引出率分别为:内耳结构正常组73.68%(14/19)、88.89%(8/9),前庭水管扩大组100%(7/7)、100%(7/7),Mondini畸形组85.71%(12/14)、100%(10/10),共同腔畸形组22.22%(2/9)、0(0/7)。术后1周内前庭功能损害症状出现率为54.55%(12/22),术后一个月cVEMP和oVEMP引出率为50%(6/12)、45.45%(5/11);VEMP损伤率为88.89%(8/9)。结论VEMP可评估患儿人工耳蜗植入前后前庭功能,内耳畸形是植入前后VEMP变化的重要影响因素,VEMP测试结果可为人工耳蜗植入侧别的选择提供一定参考。

前庭神经鞘瘤听力保留与重建技术研究进展

近年来,前庭神经鞘瘤的外科治疗目标已由降低致死/致残率、提高面神经功能保留率发展到保留和重建听力,然而目前仅30%~60%患者能够保留听力。前庭神经鞘瘤的治疗手段复杂多样,无论放射治疗、显微手术还是保守观察,都面临近、远期听力下降甚至单侧聋的结局。目前前庭神经鞘瘤听力保留及重建的相关研究较少,本文就该领域相关进展进行总结,以期促进前庭神经鞘瘤患者听力保留与听力重建研究工作的进展。

Amplitude recruitment of cochlear potential

Intracellular recordings were made from outer hair cells (OHC) and the cochlear microphonics (CM) were recorded from scala media (SM) in three turn of guinea pig cochlea, the compound action potential (CAP) were recorded at the round window (RW) before and after the animal were exposed to white noise. The results suggest that the nonlinear properties with 'saduration' of input/output (I/O) function of OHC AC recepter potential and CM were founded; the nonlinear properties with 'Low', 'Plateau' and 'high' of CAP also were investigated. After explosion, the threshold shift of CAP has about 10 dB. The I/O of OHC responses and CM were changed in a linearizing (i.e., nonlinearity loss), the 'plateau' of I/O CAP disappeared and the growth rate of CAP amplitude were larger than before explosion. The response amplitude recruitment of OHC appears to result from reduction in gain (i.e., hearing loss); It was due to the nonlinear growth function of OHC receptor potentials was changed in linearzing that the basilar membrance motion was changed in linearizing. Since intensity coding in the inner ear depends on an interactions of nonlinear basilar membrance and nerve fibers. So that it must lead to a linearizing of CAP as input responses.

人工耳蜗术后电诱发镫骨肌反射、神经反应电位与舒适阈值对比观察

目的研究人工耳蜗植入患者电诱发镫骨肌反射阈值(electrically evoked stapedius reflex thresholds,ESRT)、电诱发听神经复合动作电位(electrically evoked compound actionpotential,ECAP)阈值与主观最大舒适阈(most comfortable level,M值)的相关性。方法纳入2018年—2020年在解放军总医院耳鼻咽喉头颈外科医学部接受人工耳蜗植入的研究对象,42例人工耳蜗植入患者的43耳,年龄11~58岁,男22例,女20例,人工耳蜗植入体品牌型号分别澳大利亚Cochlear公司CI512型16例,奥地利MED-EL公司SONATAti100型或Mi10xx型23例,美国Advance Bionics公司HiRes90K型4例。通过人工耳蜗调机软件映射编程模块选择M值测量,获得各个电极通道主观最大舒适阈值。使用丹麦国际听力公司Titan听力测试平台中ESRT模块测得相同通道的植入耳同侧和对侧ESRT,再利用人工耳蜗调机软件ECAP测试模块测试相同通道ECAP阈值,分析三者间的相关性。结果42耳ESRT测试植入耳同侧ESRT引出率为71.43%,对侧ESRT测试引出率为97.54%。人工耳蜗植入耳对侧ESRT与主观M值高度相关(Cochlear公司r=0.48,P<0.001;MED-EL公司r=0.76,P<0.001;AB公司r=0.78,P<0.001)。植入耳同侧ESRT与主观M值相关性低。ECAP阈值与主观M值有显著的相关性(Cochlear r=0.78,P<0.001;MED-EL公司r=0.43,P<0.01;Advance Bionics公司r=0.78 P=0.07)。人工耳蜗植入侧对侧ESRT与ECAP阈值有显著相关性。Cochlear公司r=0.78,P<0.001;MED-EL公司r=0.44,P<0.05,Advance Bionics公司r=0.53,P=0.27)。结论人工耳蜗植入术后植入耳对侧ESRT测试所得结果与主观M值相关性高,临床人工耳蜗植入术后编程调试中ESRT可以用于对人工耳蜗植入患者最大舒适阈电刺激参数调整的参考和依据。

CHANGES IN THE ENDOCOCHLEAR POTENTIAL AND COCHLEAR BLOOD FLOW INDUCED BY ATP INFUSION AND ARTERIAL OCCLUSION

To assess the relationship between cochlear blood flow (CBF) and auditory function, a procedure of intravital microscopy for observations of the lateral wall vessels of the cochlea coupled with the simultaneous measurement of the endocochlear potential (EP) was established in guinea pigs with gradual ischemia of the cochlea. It was found that occlusions of both common carotid arteries and one of the vertebral arteries produced a minor reduction in CBF with no significant alteration in the EP. When intravenous infusion of ATP induced sharp and severe decreases in CBF, the EP varied only slightly from the baseline in some animals while there were no alteration in others. Furthermore, ATP infusions combined with arterial occlusions caused even more severe declines in CBF and a moderate decrease in the EP. The results indicate that not only does the CBF satisfy the basic needs of the processes of cochlear function, but also has a regulatory mechanism to ensure the normal function of the cochlea in the ischemia condition. It was also found that the changes in the stria vascularis vessels induced by decreases in blood pressure (BP) and heart rates were more severe than those of the spiral ligament vessels. This phenomenon indicated that the stria vascularis vessels were more sensitive to decreases of BP and heart rates.

小儿耳蜗植入后电诱发复合动作电位的阈值及其临床应用

目的 研究应用神经反应遥测 (neuralresponsetelemetry ,NRT)技术 ,测试电诱发复合动作电位 (electrically evokedcompoundactionpotential,ECAP)阈值以指导小儿人工耳蜗映射调图的策略与时机。方法 应用NRT3 0软件对幅值增长函数进行线性拟合 ,确定ECAP阈值。比较 6例儿童植入者在术后 1、2、3个月ECAP阈值的变化 ,同时比较 7例儿童术中、术后ECAP阈值的差异。结果ECAP幅值增长函数在接近阈值或进入饱和时不再呈线性。术后ECAP阈值保持稳定。各导电极的术中ECAP阈值比术后阈值平均高约 15CL ,二者有显著性相关 (R2 =0 915 4)。结论 应选取幅值增长函数的直线段部分进行拟合以确定ECAP阈值。术后应用ECAP阈值指导小儿映射调图时 ,测试一次ECAP阈值即可。

神经反应遥测技术在人工耳蜗植入术中的监测应用

目的 探讨在人工耳蜗植入术中能快速、准确地判断人工耳蜗装置的完好性和患者客观听觉反应的监测方法。方法 在 40例患儿人工耳蜗植入术中先测定电极阻抗 ,然后使用神经反应遥测技术 (neuralresponsetelemetry,NRT)监测 6个电极的电诱发听神经复合动作电位 (electricallyevokedauditorynervecompoundactionpotentials,ECAP)。结果 患儿所有电极阻抗正常 ,ECAP的检出率分别为 97 5 %(39例 / 40例 )和 92 1%(2 2 1个电极 / 2 40个电极 )。其中 33例内耳无畸形的患儿所有198个测试电极中有 195个电极测出清晰的ECAP波形 (98 5 %)。 7例内耳Mondini畸形患者共 42个测试电极中有 2 6个电极测得ECAP波形 (6 1 9%) ,两组之间差异有极显著性。靠近耳蜗底回 (高频区 )的电极比靠近蜗尖 (低频区 )的电极具有较高的ECAP反应阈值和较高的ECAP饱和阈值。结论 NRT技术可以简便、快速和准确地判断患者的听神经反应 ,可望成为术中常规监测方法 ,内耳Mondini畸形是影响ECAP检出的重要因素。

噪声对豚鼠耳蜗外淋巴谷氨酸含量及耳蜗电位的影响

目的 观察噪声暴露对豚鼠耳蜗外淋巴液中谷氨酸含量及耳蜗电位的影响。方法 应用高效液相色谱仪检测豚鼠噪声暴露耳与对照耳耳蜗外淋巴液中谷氨酸的含量 ,同时记录噪声暴露前及噪声暴露 2小时的耳蜗电位 (CM、CAP)。结果 对照耳外淋巴液中谷氨酸含量为 4 .2 7± 0 .4 0 μmol/L ,噪声暴露耳为 8.15± 0 .78μmol/L ,提示噪声暴露 2小时后外淋巴液中谷氨酸含量明显增加 (P <0 .0 5 ) ;CM相对幅度下降 ,并且其非线性特点消失 ,CAP阈值平均升高了约 5 0dB。结论 噪声暴露可以使豚鼠耳蜗外淋巴液中的谷氨酸含量明显增加 ,并引起耳蜗功能的改变。提示噪声不仅损伤外毛细胞 ,还可以使内毛细胞谷氨酸过度释放产生兴奋性毒性 ,直接引起内毛细胞及耳蜗传入神经的损伤。

次声暴露对豚鼠听神经动作电位的影响

目的 :系统观察在 1 2 5 d B SPL (sound pressure level,SPL )次声暴露下豚鼠听神经动作电位 [actionpotential N1 ,AP (N1 ) ]的潜伏期及听阈的变化。方法 :采用面神经管长期置入电极引导记录的方法记录 AP(N1 ) ,并将次声暴露后豚鼠的听阈及潜伏期与听力正常豚鼠进行对比观察。结果 :1 2 5 d B SPL次声暴露可引起听阈不同程度的升高 ,一般在 6～ 9d内听阈可完全恢复 ;潜伏期的恢复要早于听阈的恢复。结论 :SPL为 1 2 5 d

钙泵间接激活剂对噪声性聋的保护作用

目的 探讨Ca2 +泵间接激活剂佛波酯 (phorbol 12 myristate 13 acetate ,PMA)对噪声性聋的保护作用。方法 杂色豚鼠随机分为 2组 :PMA组和人工外淋巴液组 (对照组 ) ,分别全耳蜗灌流 3μmol/LPMA和人工外淋巴液并暴露于 10 0dBSPL的白噪声持续 12 0min。于噪声暴露前和噪声暴露后 12 0min圆窗记录耳蜗微音电位 (cochlearmicrophonics ,CM)和耳蜗听神经复合动作电位 (compoundactionpotential,CAP)。比较两组相同时间点的CM幅度和CAP阈值。结果 噪声暴露前两组CM幅度和CAP阈值差异无显著性 (P >0 0 5 )。噪声暴露后两组CM幅度下降和CAP阈值升高 ,但PMA组CM幅度高于对照组 ,CAP阈值低于对照组 (P <0 0 5 )。结论 Ca2 +泵间接激活剂PMA对噪声性聋有部分保护作用。