豚鼠声诱发短潜伏期负电位的来源初探

Objective To establish a model of acoustically evoked short latency negative response (ASNR) in guinea pigs, a model of profound hearing loss with normal saccular functions, and verify the correlation between ASNR and vestibular evoked myogenic potential (VEMP). Methods Thirty-two healthy guinea pigs were employed in the experiment, which were randomly divided into control group ( 16subjects) and deafened group (16 subjects). Each animal experienced auditory and vestibular tests including auditory brainstem response ( ABR), VEMP and caloric test. A quick treatment was employed for deafened group consisting of a subcutaneous injection of kanamycin at a dose of 400 mg/kg followed by a jugular vein injection of ethacrynic acid at a dose of 40 mg/kg one hour later. The animals were received ABR, VEMP and caloric test 7 - 10 days following the drug administration. The deafened group was further divided into ASNR group and non-ASNR group, based on the presence of ASNR. Results In deafened group, five subjects died postoperatively, 11 subjects (22 ears) provided full data, ASNR was elicited in eight ears (36.4%), the threshold was 120- 130 dB SPL with mean of (124.4 ±4.96) dB SPL. Its latency range was 1.75 - 2. 60 ms with mean of ( 2. 15 ± 0. 27 ) ms. The mean latency of threshold was (2. 34 ±0. 18) ms. All eight ASNR ears presented with VEMP. The VEMP threshold, positive and negative potential latencies proved no statistical difference (P ＞ 0. 05 ) between ASNR group and control group.Significant difference was detected between the VEMP presence of ASNR group and non-ASNR group ( P =0. 002). There was no statistically significant correlation between VEMP and caloric test neither between ASNR and caloric test in deafened group. Conclusions This study evoked ASNR in an ototoxicity guinea pig model which has profound hearing loss with normal saccular functions. The presence of ASNR correlated with VEMP, however, not correlated with caloric test, suggesting that ASNR and VEMP are both originated from the saccule.     

声诱发短潜伏期负电位豚鼠的内耳铺片研究

目的 在耳毒性损伤的豚鼠模型上诱发声诱发短潜伏期负电位( acoustically evoked short latency negative response,ASNR),通过内耳铺片观察ASNR豚鼠的基底膜球囊、椭圆囊及半规管壶腹的组织形态学特点,验证豚鼠ASNR的责任终器.方法 将45只健康豚鼠按随机数字表法分为2组,健康对照组15只(30耳),药物致聋组30只(60耳).致聋组给药(硫酸卡那霉素+利尿酸)致聋7～10d后,行听觉脑干反应(ABR)测试,根据ASNR引出情况进一步分为ASNR组和非ASNR组.三组豚鼠断头取颞骨,解剖显微镜下取出基底膜、球囊斑、椭圆囊斑和壶腹嵴,通过显微镜观察毛细胞数目和形态变化.结果 致聋组有27只动物(54耳)完成测试,其中45耳达到重度感音神经性聋,19耳引出ASNR(35.2％),阈值为110～125 dBSPL,平均阈值(121.7±4.5)dBSPL,潜伏期1.80～2.08 ns,平均潜伏期(1.93±0.07)ms.铺片观察显示,基底膜、球囊、随圆囊、壶腹嵴毛细胞密度按正常对照组、ASNR组、非ASNR组依次减低,毛细胞损伤程度依次加重.ASNR组球囊微纹区、周边区毛细胞密度与对照组差异无统计学意义(P值均＞0.05);其他各组的相应比较,差异均有统计学意义(P值均＜0.05).结论 豚鼠ASNR的责任终器是球囊,而不依赖于耳蜗、椭圆囊及半规管功能.     

人类声诱发短潜伏期负电位的研究

目的在极重度感音性聋耳的ABR检测中发现一个位于3～4ms潜伏期的"V"字形负向波形,称声诱发短潜伏期负电位(Acoustically Evoked Short Latency Negative Response,ASNR)。本研究通过大宗病例调查和临床实验来探讨ASNR的特点和起源。方法回顾性调查并分析3104例ABR检测结果,以详尽了解ASNR的出现率和特性。对20名双耳极重度感音性耳聋患者(6～62岁)和12名健康人(23～30岁)进行了ABR和前庭诱发肌源性电位(VEMP)测试。患者组包括了16名人工耳蜗植入术后的患者,植入耳在裸耳状态时可提供无功能耳蜗模型。结果判读侧重于:人工耳蜗植入耳能否诱发ASNR,以及对比在极重度感音性聋耳中ASNR组和非ASNR组的VEMP出现率及反应阈值。结果ASNR仅出现于极重度感音性聋耳,并且对强声刺激(80～120dBnHL)有依赖性。在653例极重度感音性聋患者(981耳)的ABR波形中,有80例(12.3%)117耳(11.9%)出现了ASNR。ASNR有良好的重复性,可排除伪迹干扰的可能性。ASNR具有神经电位的特征,表现在随着声刺激的增强,其潜伏期缩短而振幅增大。ASNR与ABR的波形完全不一样,无法将其解释为传统听觉神经通路产生的电位。临床实验中,3个人工耳蜗植入耳能诱发出ASNR,说明ASNR的发生与耳蜗无关。所有9个ASNR耳都诱发出VEMP,且阈值与正常对照组无统计学差异(P>0.05),提示ASNR耳具有正常的球囊功能。在非ASNR组中,三分之二没有引出VEMP,而另外三分之一虽然可以诱发出VEMP,但阈值明显较正常对照组高(P<0.01),分别提示球囊功能丧失或低下。此外,有一外半规管麻痹耳诱发出了ASNR和VEMP。结论ASNR并非伪迹,而是一种依赖强声刺激,且只出现于极重度感音性聋耳的神经电位。ASNR的出现完全依赖于正常的球囊功能,而不依赖于残余听力或者半规管功能。据此认为ASNR起源感觉器官为球囊,根据其潜伏期推测电位源自前庭神经核。     

声诱发短潜伏期负电位

本文主要对声诱发短潜伏期负电位的起源、特点,与前庭诱发电位的关联及在临床诊断方面的重要作用等进行综述.     

声诱发短潜伏期负电位

本文主要对声诱发短潜伏期负电位的起源、特点，与前庭诱发电位的关联及在临床诊断方面的重要作用等进行综述。     

不同频率短纯音刺激声对颈肌前庭诱发肌源性电位的影响

目的　比较健康青年人不同频率短纯音刺激声对颈肌前庭诱发肌源性电位（cervical VEMP,cVEMP）结果的影响,探讨500 Hz和1000 Hz短纯音对cVEMP潜伏期、幅度、幅度比和不对称度的影响。方法　29名健康青年人,其中男15名,女14名,共58耳,采用随机函数确定测试顺序,分别采用500 Hz和1000 Hz短纯音为刺激声,行cVEMP测试。记录cVEMP的P1、N2潜伏期、幅度、幅度比和不对称度等参数。结果　500 Hz比1000 Hz记录到cVEMP潜伏期更长,具有显著性差异（t P1=10.50,t N1=11.38,P 均<0.05）。500 Hz比1000 Hz记录到的校正前后幅度更高（t 校正前=10.01,t 校正后=-8.03,P 均<0.05）。两种频率记录到的cVEMP幅度比和不对称度比较,差异无统计学意义（P 均>0.05）。相同频率记录到cVEMP幅度比和不对称度在幅度校正前后的数值比较,差异无统计学意义（P 均>0.05）。结论　500 Hz可记录到幅度更高的cVEMP,有助于临床判断并分析波形。幅度校正对幅度比和不对称度结果无影响。     

声诱发的短潜伏期负反应与前庭诱发的肌源性电位关系初步研究

目的研究声诱发的短潜伏期负反应(acoustically evoked short latency negative response,ASNR)的特点,并初步证实该电位的前庭源性,即与前庭诱发的肌源性电位(vestibular evoked myogenic potentials,VEMP)同源。方法分别检测28例健康成人、16例前庭疾病和1例全聋患者的VEMP和ASNR,比较ASNR与VEMP之间的关系。结果ASNR正常引出率为87.5%,潜伏期正常值为3.50±0.25ms;2倍标准差作为正常值的上、下限,ASNR潜伏期的范围为3~4ms,阈值为80~90dB nHL。16例前庭疾病患者均行双侧检查,在VEMP消失的9耳(9例)中,ASNR均未引出;VEMP低振幅的8例(8耳)中,5例(5耳)未引出ASNR,3例(3耳)ASNR正常引出。5例梅尼埃病患者接受甘油试验,1例(2耳)甘油试验前后VEMP与ASNR均正常,2例(4耳)双侧VEMP与ASNR甘油试验前异常,甘油试验后正常,1例(1耳)患侧VEMP正常,甘油试验前后无变化,ASNR由异常变为正常;1例(2耳)VEMP甘油试验前双侧异常,甘油试验后正常,但ASNR均未引出。1例听力正常的前庭神经炎患者,患侧VEMP未引出,ASNR电位也未引出。1例先天性全聋患者人工耳蜗植入前,VEMP、ASNR正常引出;植入后,术侧VEMP振幅降低,ASNR未引出。结论ASNR与VEMP可能均源于球囊。鉴于目前的结果,在不便进行VEMP检测时可用ASNR替代。     

健康飞行员与飞行学员气导声诱发的在眼外肌上记录的前庭诱发肌源性电位

目的记录中国空军战斗机飞行(学)员气导声诱发的oVEMP(ocular vestibular-evoked myogenic poten-tial,眼外肌上诱发的前庭肌源性电位)的特征性参数,以便建立战斗机飞行(学)员的正常值数据。方法 62名健康飞行学员(30名男性和32名年龄匹配的女性)和31名现役健康战斗机飞行员作为受试者,采用气导短纯音(short tone burst,STB)双侧给声双侧进行记录。记录93名健康飞行(学)员STB-oVEMP的nI和pI潜伏期、nI-pI间期、nI-pI的波间幅度以及双侧幅度不对称比,以获得正常值数据。对年龄与性别对oVEMP的影响也进行了观察。结果 93名健康飞行(学)员oVEMP的nI和pI潜伏期、nI-pI间期、nI-pI的波间幅度以及双侧幅度不对称比分别为(10.35±0.66)ms,(15.18±1.07)ms,(4.75±0.99)ms,(6.75±4.13)μV,以及(13.22±9.13)%。男性飞行学员与男性现役战斗机飞行员间在oVEMP的各个特征性参数上无显著差别。年龄匹配的男女性飞行学员仅在nI-pI的波间幅度上存在显著差别,分别为男性(6.96±3.85)μV和女性(5.47±3.10)μV。结论在oVEMP幅度上存在性别差异,年龄对oVEMP参数似乎没有影响。因此应该采用双侧幅度不对称比而不能仅仅采用绝对幅度参数来评估oVEMP的检测结果。飞行(学)员需要按照性别分别建立oVEMP的正常值范围。     

健康青年人骨导前庭诱发肌源性电位临床正常值的建立北大核心CSCD

目的 建立本实验室健康青年人骨导前庭诱发肌源性电位(bone-conducted vestibular evoked myogenic potential)的临床正常值范围。方法 选择30名(60耳)健康青年人为研究对象,男15人,女15人,平均年龄(25.28±4.32)岁,使用B81骨振子进行骨导振动(bone-conducted vibration,BCV)诱发的颈肌前庭诱发肌源性电位(cervical vestibular evoked myogenic potentials,cVEMP)和眼肌前庭诱发肌源性电位(ocular vestibular evoked myogenic potentials,oVEMP)检测,以60dB nHL给声强度作为起始刺激强度,记录BCV-cVEMP和BCV-oVEMP的引出率、潜伏期、波间期、波幅和阈值,采用SPSS22.0统计软件进行统计学分析。结果 BCV-cVEMP和BCV-oVEMP的引出率均为100%(60/60);BCV-cVEMP的阈值为(41.80±2.99)dB nHL,P1、N1潜伏期分别为(16.05±1.76)ms和(26.43±2.66)ms,波间期为(10.11±2.03)ms,波幅为(86.93±60.45)μV;BCV-oVEMP的阈值为(45.00±3.50)dB nHL,P1、N1潜伏期分别为(18.25±2.40)和(12.19±2.31)ms,波间期为(6.09±0.99)ms,波幅为(10.33±9.90)μV。受试者左右耳BCVcVEMP和BCV-oVEMP的P1潜伏期(P=0.421,P=0.672),N1潜伏期(P=0.889,P=0.662),波间期(P=0.116,P=0.553),波幅(P=0.819,P=0.509)和阈值(P=0.425,P=0.090)差异均无统计学意义(P>0.05)。结论 BCV-VEMP对于健康青年人是一项稳定可靠的前庭功能检查。本实验室健康青年人BCV-VEMP正常值的建立,可为BCV-VEMP的临床应用提供参考。     

脉冲角加速度刺激诱发豚鼠短潜伏期前庭诱发电位

以脉冲角加速度刺激在豚鼠记录出短潜伏期诱发反应，反应由发生于刺激开始后10ms以内的5～7个波组成，高强度刺激时反应振幅数微伏，I波潜伏期约2．5ms，不同动物及同一动物不同时间测试反应非常稳定。系列实验结果表明脉冲角加速度刺激诱发的豚鼠短潜伏期诱发反应系前庭诱发电位。     

Vestibular evoked myogenic potentials of undiagnosed dizziness

OBJECTIVE: Recording of vestibular evoked myogenic potentials (VEMP) can facilitate the evaluation of otolith function. The dizziness caused by otolith lesions is not completely understood. To clarify which symptoms of dizziness originate from the otolith organs, we examined the relationship between symptoms and VEMP results in patients with undiagnosed dizziness. METHODS: The subjects were 18 patients with undiagnosed dizziness aged less than 40 years who underwent VEMP examination. The VEMP results were evaluated using the interaural ratio of p13-n23 amplitude. RESULTS: Abnormal VEMP results were obtained in five of seven patients who experienced a sensation of falling (p=0.013), in none of the three patients who experienced a swaying sensation (p>0.05), and in one of eight patients who experienced a floating sensation (p>0.05). Five of six patients with abnormal VEMP results complained of disequilibrium lasting a few seconds. CONCLUSIONS: Dizziness with a sensation of falling lasting for a few seconds was related to abnormal VEMP results, suggesting that it resulted from saccular dysfunction. VEMP examination may be considered a useful modality in the diagnosis of dizziness of unknown origin.     

不同刺激模式前庭诱发肌源性电位的反应特性

目的 前庭诱发的肌源性电位(vestibular evoked myogenic potential,VEMP)可用于评价球囊功能及其对称性,比较3种刺激模式VEMP的振幅与潜伏期,希望得出适合临床应用的方法。方法 测量21名健康成人3种刺激模式(双侧短声、1侧短声和1侧短声对侧白噪声)的VEMP的潜伏期、振幅,计算出3种情况下的振幅及潜伏期的均值、双侧振幅比值、双侧振幅不对称性。结果 3种刺激模式刺激侧振幅与潜伏期无明显差异,但1侧短声刺激对侧振幅低于刺激侧,潜伏期比刺激侧长2-3 ms。双侧短声刺激p13波和n23波出现率为100％,1侧短声对侧白噪声刺激p13和n23出现率最低,无特别应用的意义。3种刺激方式VEMPs振幅变化较大。结论 VEMP是一种稳定的肌源性电位,双侧短声刺激和1侧短声刺激都不失为较好的刺激方法,双侧给声对双侧听力正常者较为适宜。应用双侧VEMP的振幅比值和对称性,判断双侧球囊的功能。     

An acoustically evoked short latency negative response in profound hearing loss infants

OBJECTIVE: A large negative deflection with a 3-4 ms latency within the auditory brainstem response has been reported in some profound hearing loss ears under intense stimuli in adult subjects. The wave has been termed the N3 potential or acoustically evoked short latency negative response and it is assumed to be a vestibular-evoked potential. The purpose of the current study was to investigate the relationship between the vestibular-evoked myogenic potentials and the acoustically evoked short latency negative response in infants with a functionless cochlea and normal or impaired semicircular canal. METHODS: Seventeen 3 months old infants with profound bilateral sensorineural hearing loss had acoustically evoked short latency negative responses and vestibular-evoked myogenic potentials recorded and caloric tests performed. RESULTS: No spontaneous symptoms of vestibular dysfunction were found in the examined infants. ASNR with medium latency 3.3 ms and threshold value 80-90 dB normal hearing level was elicited from 10 ears. VEMPs were present in 12 ears. ASNRs and VEMPs were absent in two ears with normal response to caloric stimulation. No response to caloric stimulation was elicited from other two ears with normal saccular function. For the ears with absence of ASNR, four had normal VEMP and the rest were considered to have saccular afunction. Significant correlation was found between the presence of ASNRs and VEMPs. CONCLUSION: Acoustically evoked short latency negative responses could be a valuable tool for assessing vestibular function in infants with profound sensorineural hearing loss.     

Vestibular evoked myogenic potentials in children after cochlear implantation

Objective

The aim of this study was to report the effect of unilateral cochlear implantation to vestibular system using vestibular evoked myogenic potentials (VEMPs) by air-conduction in a sample of children aged less than 5 years.

Materials

This study consisted of 10 children (6 boys and 4 girls), who underwent cochlear implantation surgery at our clinic, and 8 normal hearing children (5 boys and 3 girls) matched for age. The VEMPs were performed before, 10 days, and 6 months after surgery. Both the implanted and unimplanted ears of each child were evaluated, with the cochlear implant both off and on.

Results

Preoperatively, six (60%) children had abnormal VEMPs responses on both ears. In the postoperative sessions, no child showed any VEMPs response on the implanted side. The VEMPs were not recorded on the unimplanted side either, except for one case. At 6 months, the VEMPs response on the unimplanted side of three children became normal when the cochlear implant was on, and in two children with the device off.

Conclusion

In the postoperative 6-month-period, the disappearance of VEMPs suggests that the saccule of children can be extensively damaged following cochlear implantation. A recovery of VEMPs can take place on the unimplanted side, with the cochlear implant both on and off. Despite this saccular injury, the absence of clinical signs in children could be explained by their ability to effectively compensate for such vestibular deficits.     

前庭诱发肌源性电位的正常人群观察

目的:观察我国正常青年人群中前庭诱发肌源性电位(VEMP)出现的阳性率及各项参数指标。方法:选取52例(男31例,女21例)21~22岁正常健康人群,以短声为刺激声,单耳给声,同侧胸锁乳突肌(SCM)记录。结果:47例2耳均可引出VEMP,5例2耳均不能引出。总104耳中,94耳阳性,10耳阴性,阳性率90%。统计阳性耳各参数:p1潜伏期(15.97±3.22)ms、n2潜伏期(24.41±2.46)ms、p1n2间期(8.41±2.06)ms,幅值(33.27±14.37)μV,阈值(93.67±5.20)dB nHL。统计47例正常人同一个体耳内差异的各参数为p1潜伏期(0.97±1.31)ms,n2潜伏期(1.23±1.30)ms,p1n2间期(0.95±1.21)ms,幅值(10.04±11.88)μV,阈值(2.29±2.56)dB nHL。男女各参数比较差异无统计学意义。结论:绝大部分正常人可引出VEMP。VEMP的引出体现该侧耳球囊→前庭下神经→脑干前庭神经核→前庭脊髓通路→颈肌运动神经元这条反射途径的完整性。VEMP可能成为一种检测前庭终器及其传导通路完整性的方法。     

人工耳蜗植入术中电刺激中潜伏期听觉诱发电位的检测

目的 建立人工耳蜗植入术中电刺激中潜伏期听觉诱发电位(electrical evoked middle latency response,EMLR)的检测方法,为进一步评估植入者听觉传导通路及高位听觉反应的特点奠定基础.方法 20例人工耳蜗植入者,其中语前聋14例,语后聋6例,全部使用Cochlear公司Nucleus CI24R (CA)人工耳蜗.术中将言语处理器与计算机接口及听觉诱发电位仪触发端口连接,电极植入后,选取第3号电极,先常规进行电刺激听神经复合动作电位(electrically evoked auditory nerve compound active potentials,ECAP)测试初步了解听神经功能状态,然后进行EMLR检测.选择电刺激听性脑干反应(electrical auditory brainstem response,EABR)模式,采用单极刺激,双相交替脉冲电流方波,脉宽50 ～ 100μs,强度(电流级,current leve1,CL)由ECAP阈值上20 CL起,以5 CL为步长递减或递增,听觉诱发电位仪记录EMLR波形.对ECAP阈值与EMLR阈值进行相关性分析.另外选择6名听力正常健康受试者,行声刺激中潜伏期听觉诱发电位(auditory middle latency response,AMLR)测试,作为EMLR波形和潜伏期的声刺激对照.结果 6例听力正常受试者均可记录到AMLR波形,平均反应阈为(12.5±8.6)dBnHL,接近纯音测听阈值(10.8 ±7.3)dBHL.20例人工耳蜗植入者均可记录到EMLR波形,与AMLR波形相似,但各波潜伏期和波间期缩短,波幅变化不大;语前聋较语后聋总体上波幅小,潜伏期长.EMLR平均阈值为(140.55 ±9.92)CL,低于ECAP的平均阈值 ( 160.75±13.34) CL,差异具有统计学意义(t=10.467,P＜0.01);二者阈值之间呈正相关(r=0.763,P＜0.01).结论 人工耳蜗植入术中可成功记录到EMLR波形,其阈值较ECAP低,可以作为判断植入者中枢高位听觉传导功能的客观检查.