皮层传出调控对畸变产物耳声发射的影响

目的 研究听皮层传出调控对耳蜗外毛细胞主动机械特性的影响。方法 ①自行设计视觉选择注意任务,观察９例健康人选择注意对畸变产物耳声发射（ｄｉｓｔｏｒｔｉｏｎ ｐｒｏｄｕｃｔ ｏｔｏａｃｏｕｓｔｉｃ ｅｍｉｓ－ｓｉｏｎｓ,ＤＰＯＡＥ）的影响。视觉任务为计算机屏幕上的Ｏ和Ｑ字母,字母Ｑ为靶刺激,字母Ｏ为非靶刺激;②在１０只（１５耳）豚鼠的中脑上下叠体（丘）之间切断大脑与脑干的联系,造成去大脑僵直的动物模     

畸变产物耳声发射对侧抑制效应的研究

利用ＩＬＯ９２耳动态分析仪，测试２３例（４６耳）正常青年人的畸变产物耳声发射（ＤＰＯＡＥ）和对侧窄带噪声（ＮＢＮ）的影响。结果：（１）对侧ＮＢＮ对ＤＰＯＡＥ的抑制非常明显，随ＮＢＮ强度增加ＤＰＯＡＥ幅值下降增加，二者呈显著负相关（Ｆ２为１～６ｋＨｚ，γ为－０．４９～－０．２４，均Ｐ〈０．０５，斜率０．２６～０．０８ｄＢ／１０ｄＢ）。（２）在Ｆ２为中频（１．２ｋＨｚ）且为中等强度（４５～６５ｄＢＳＰ     

新生儿高胆红素血症的瞬态诱发性耳声发射测试

高胆红素血症是新生儿多种疾病的重要症状,重者可导致脑神经系统损害,常留有语言、智能及听力发育障碍。７０年代后国内外学者用听性脑干电反应测听（ＡＢＲ）监测高危儿听力,近几年国外学者又用瞬态诱发性耳声发射（ＴＥＯＡＥ）进行监测,为探讨其临床应用价值,对２...     

选择注意对耳声发射的影响

耳蜗传出神经系统是近下来耳科学研究热点之一，耳声发射的成功记录为研究耳蜗传出系统功能开辟了新道路，除电刺激及对侧和（或）同侧声刺激可使耳蜗传出神经系统激活或兴奋外，高级神经中枢活动也可影响其兴奋性，耳蜗传出神经系统兴奋，抑制耳蜗旋器外毛细胞活动，表现为耳声发射幅值下降，选择注意是研究皮层高级神经中枢活动的主要方法之一，本综述选择注意对耳声发射的影响，以探讨皮层高级神经中枢活动对耳蜗主动微机制的调     

高血脂豚鼠畸变产物耳声发射及耳蜗形态学观察

目的观察高血脂对豚鼠耳蜗形态和畸变产物耳声发射的影响。方法建立豚鼠高血脂模型，检测其畸变产物耳声发射，观察光镜及电镜下耳蜗形态学改变。结果高血脂组豚鼠畸变产物耳声发射各频率反应幅值均较正常组低；光镜下Corti器变形，基底膜结构破坏；电镜下外毛细胞排列紊乱，线粒体、内质网结构破坏。结论高血脂可造成豚鼠耳蜗外毛细胞线粒体和内质网损伤，导致畸变产物耳声发射幅值下降。     

胆固醇增高患者畸变产物耳声发射检查

耳声发射作为一种客观、无创、敏感的耳科检查,已在临床广泛应用,它可以反映耳蜗功能的早期变化,提示耳蜗损害[1]。我们对40例（80耳）胆固醇增高患者进行畸变产物耳声发射（distortion product otoacoustic emisson,DPOAE）检查,分析其耳蜗功能状态及听力受损情况,为临床治疗提供参考。     

豚鼠畸变产物耳声发射潜伏期的对侧抑制效应现象

目的 通过观察对侧抑制效应中畸变产物耳发射（distortion productotoacousticemissions,DPOAE)各指标的改变,探讨耳蜗生理机制及传出神经的调节机能。方法 12只健康杂色豚鼠分A、B2组,在对侧耳无声刺激及给予70dB SPL宽带噪声条件下,分别使用不同的原始纯音强度组合测定在f2＝2、4、6kHz时测试耳DPOAE之幅值及潜伏期。次日,A组动物背侧径路开放右耳听泡,圆窗膜给予60mmol/L卡因酸1μL,作用3h后拭去。给药后6h测试右耳无声刺激和给予70dB SPL宽带噪声刺激下,左耳的DPOAE幅值、潜伏期等指标。结果 ①用药前,A组对侧耳给声时以等强度原始音诱发的测试耳DPOAE各频率幅值与给声前基本无变化,而潜伏期显著延长;②用药前,B组对侧耳给声以差强度原始音（L2＝L1－10dB)诱发的测试耳DPOAE在2、4kHz的幅值与给声前相比有显著减小,潜伏期也显著延长;③A组用药后,对侧耳给声对测试耳DPOAE幅值和潜伏期均无显著影响。结论 潜伏期亦是对侧抑制研究中的敏感指标。对侧抑制效应在调制耳蜗转导机制中发挥负反馈作用。     

豚鼠外淋巴瘘对畸变产物耳声发射的影响

为观察豚鼠外淋巴瘘造模后畸变产物耳声发射的变化，选用１１只豚鼠右耳为实验耳，手术建立蜗窗外淋巴瘘。在实验前，打开听泡，蜗窗膜造瘘，缝合伤口及外淋巴瘘造后１８天，均以２ｆ１－ｆ２ｚＤＰＯＡＥ的幅值记录其变化。测试完毕后豚鼠耳蜗行火棉胶包埋切片，观察形态学改变。结果发现在形成蜗窗膜外淋巴瘘前后ＤＰＯＡＥ幅值变化差异有显著性（Ｐ〈０．０１），１８天后蜗窗膜愈合者ＤＰＯＡＥ幅值明显提高，接近实验前，而未愈     

短时纯音暴露对畸变产物耳声发射的影响

畸变产物耳声发射（ＤＰＯＡＥ）测试所采用的参数可以对测试结果有明显影响，为研究改变ＤＰＯＡＥ测试参数对反映耳蜗功能变化是否有影响，使１０只大白兔（１６耳）接触短时（３分钟）、中等强度（８２ｄＢ ＳＰＬ）的纯音暴露后发现，以等强原始音（Ｌ１＝Ｌ２）诱发的ＤＰＯＡＥ的幅度变化小于以差强原始音（Ｌ２＝Ｌ１－１２ｄＢ）诱发的ＤＰＯＡＥ（相差１０．１１ｄＢ），而其恢复过程也短于后者（相差１００．７１秒）。这     

短时纯音暴露对畸变产物耳声发射的影响

畸变产物耳声发射（ＤＰＯＡＥ）测试中所采用的参数可以对测试结果有明显影响，为研究改变ＤＰＯＡＥ测试参数对反映耳蜗功能变化是否有影响，使１０只大白兔（１６耳）接触短时（３分钟）、中等强度（８２ｄＢＳＰＬ）的纯音暴露后发现，以等强原始音（Ｌ１＝Ｌ２）诱发的ＤＰＯＡＥ的幅度变化小于以差强原始音（Ｌ２＝Ｌ１－１２ｄＢ）诱发的ＤＰＯＡＥ（相差１０．１１ｄＢ），而其恢复过程也短于后者（相差１００．７１秒）。这种差别可能提示在ＤＰＯＡＥ的产生过程中有多个生理机制发挥作用，而变化测试参数则可以选择性地突出表现其中某一个机制     

正常清醒豚鼠的畸变产物耳声发射特性

目的 研究正常清醒豚鼠的畸变产物耳声发射（ＤＰＯＡＥ）的特性。方法 采用ＣＥＬＥＳＴＡ ５０３型耳声发射分析仪对２６只正常清醒豚鼠（３５耳）进行ＤＰ图及ＤＰ输入／输出曲线（ＤＰ－Ｉ／Ｏ）的测试，随机选择１１只正常清醒豚鼠（２０耳）进行ＤＰＯＡＥ的重复测试，用ＳＰＳＳ１０．０对数据进行统计分析。结果 在ＤＰ图中，当初始音强度Ｌ１／Ｌ２为 ７０／６５ ｄＢ ＳＰＬ时，正常清醒豚鼠的 ＤＰＯＡＥ幅值随测试频率ｆ０从０．７５－８ｋＨｚ的增加而逐渐升高（２７．９０±１．９６－5０．６５±０．７１）。在 ＤＰ－Ｉ／Ｏ中，当ｆ０分别为４、６、８ ｋＨｚ时，正常清醒豚鼠的ＤＰＯＡＥ幅值随Ｌ１／Ｌ２从７０／６５以５ｄＢ－挡降至１５／１０ ｄＢ ＳＰＬ而呈线性下降（Ｐ＜０．０１），在Ｌ１／Ｌ２为５５／５０或６０／５５ ｄＢ ＳＰＬ处出现饱和或低谷，同一Ｉ／Ｏ曲线上Ｌ１／Ｌ２分别从７０／６５及５５／５０ ｄＢ ＳＰＬ递减至阈值的Ｉ／Ｏ斜率（分别记为ＫＴ及ＫＬ）均接近于１，且ＫＬ大于ＫＴ（Ｐ＜０．０１）。重复测试的ＤＰＯＡＥ幅值差异小（＜ １ｄＢ ＳＰＬ）且无统计学意义（Ｐ＞０．０５）。结论 正常清醒豚鼠ＤＰＯＡＥ测试充分表现了其捡出率高、反应幅值大     

正常新生儿畸变产物耳声发射

目的研究新生儿畸变产物耳声发射（ＤＰＯＡＥ）听力筛选的最佳时机,了解正常新生儿ＤＰＯＡＥ的基本特征;方法应用Ｃｅｌｅｓｔａ５０３型耳声发射分析仪对２０名正常新生儿出生后１～５天逐日进行ＤＰＯＡＥ测试。结果随新生儿天龄的增加,ＤＰＯＡＥ的检出率及反应幅值逐渐提高。ｆ０为０．５ｋＨｚ时,ＤＰＯＡＥ的检出率较低,且反应不稳定。ｆ０≥０．７５ｋＨｚ时,ＤＰＯＡＥ的检出率迅速接近或达到１００％,大部分测试频率在出生１～２天的反应幅值显著低于后几天,至出生后第３天,ＤＰＯＡＥ的检出率及反应幅值均趋于稳定;结论新生儿ＤＰＯＡＥ听力筛选的适宜天龄应在其出生后３天或３天以上。０．５ｋＨｚ不宜作为新生儿ＤＰＯＡＥ的听力筛选频率。ＴＥＯＡＥ和ＤＰＯＡＥ相应频谱的反应幅值有显著相关性。两种耳声发射在新生儿听力筛选中各有优缺点     

Effects of Olivocochlear Feedback on Distortion Product Otoacoustic Emissions in Guinea Pig

Activation of ipsilaterally responsive olivocochlear (OC) neurons by sound produces rapid, post-onset alterations in the 2f1-f2 distortion product otoacoustic emission (DPOAE). The present study investigates the frequency and level dependence of this ipsilateral OC effect in the anesthetized guinea pig, compares its magnitude and sign to OC effects elicited by contralateral sound ("contralateral" OC effect), and characterizes the influence of such activity on steady-state DPOAE amplitude. DPOAEs were measured with fine time resolution in response to primary stimuli varied systematically in frequency and level. DPOAEs showed rapid and remarkably stereotyped post-onset amplitude alterations. These ipsilateral OC effects were greater for high (8-12 kHz) than for low (2-4 kHz) f2 primary frequencies and for higher primary levels (70-80 dB SPL). For any f2/f1 pair, the sign as well as the magnitude of the ipsilateral effects varied with. primary level ratio. For example, with L1 fixed at 75 and L2 varied in 1-dB steps from 60 to 75 dB SPL, DPOAE amplitude underwent a stereotyped progression from post-onset increases at the lowest levels of the f2 primary to post-onset decreases at the highest levels. At intermediate levels, near the region of sign change (L2 = 5-10 dB below L1), post-onset effects were often particularly large (as great as 20 dB). These large ipsilateral OC effects were always associated with "dips" in the DPOAE amplitude vs. level functions, and both disappeared after OC section. Although smaller in magnitude, contralateral OC effects were identical to ipsilateral effects in frequency and level dependence and in form.     

水杨酸钠急性注射对清醒豚鼠畸变产物耳声发射的影响

目的研究急性注射水杨酸钠对清醒豚鼠畸变产物耳声发射（DPOAE）的影响及其特征，探讨其对外毛细胞（OHC）的毒性作用。方法采用CELESTA 503型耳声发射分析仪在清醒豚鼠上记录DPOAE（包括DP听力图及DP输入／输出函数曲线）来监测水杨酸钠对耳蜗及毛细胞功能的影响；急性水杨酸钠实验组及生理盐水对照组分别在注药前及注药后2、4、8h进行DPOAE测试；测试结果采用SPSS10．0统计软件进行分析。结果急性水杨酸钠注射主要引起DPOAE幅值和I／O斜率分别可逆性下降和升高，注射后2h变化最大，8h基本恢复；某些频率或强度的DPOAE幅值、I／O斜率在注药后与注药前结果有统计学差异（P〈0．01或P〈0．05），特别是8kHz。结论DPOAE幅值和I／O斜率分别叮逆性下降和升高表明OHC能动性下降，即耳蜗OHC功能改变为其耳毒性作用之一。     

正常新生儿畸变产物耳声发射测试

目的　了解正常新生儿畸变产物耳声发射基本特点及影响测试结果的因素。方法　采用耳声发射分析仪Celesta 5 0 3对正常新生儿 112耳及正常听力成人 12 6耳进行DPOAE听力图测试 ,Medisoft96统计学分析。结果　正常新生儿DPOAE总检出率为 86 6 % ,DPOAE听力图在 75 0、10 0 0、2 0 0 0、40 0 0Hz点与对照组检出率统计学无显著性差异。在 75 0和 40 0 0Hz各有一高峰 ,3 0 0 0Hz有一低谷 ,出生五天后DPOAE检出率明显高于出生五天内的新生儿 ,DPOAE听力图测试耗时 11分钟左右。结论　DPOAE结果受新生儿活动、新生儿天龄 ,探头放置及本底噪声等因素影响。在大群体新生儿听力筛选时 ,选择DPOAE听力图的 75 0、10 0 0、2 0 0 0及 40 0 0四个频率点作为筛选频率 ,筛选时机选择出生五天后 ,可能有较大的价值     

Temperature Dependence of Anuran Distortion Product Otoacoustic Emissions

To study the possible involvement of energy-dependent mechanisms in the transduction of sound within the anuran ear, distortion product otoacoustic emissions (DPOAEs) were recorded in the northern leopard frog over a range of body temperatures. The effect of body temperature depended on the stimulus levels used and on the hearing organ under investigation. Low-level DPOAEs from the amphibian papilla (AP) were reversibly depressed for decreased body temperatures. Apparently, DPOAE generation in the AP depends on metabolic rate, indicating the involvement of active processes in the transduction of sound. In contrast, in the other hearing organ, the basilar papilla (BP), the effects of body temperature on DPOAEs were less pronounced, irrespective of the stimulus levels used. Apparently, metabolic rate is less influencing DPOAE generation. We interpret these results as evidence that no amplifier is involved in sound transduction in the BP. The passive functioning of the anuran BP would place this hearing organ in a unique position within tetrapod hearing, but may actually be beneficial to ectothermic species because it will provide the animal with a consistent spectral window, regardless of ambient or body temperature.     

早产儿畸变产物耳声发射特征研究

目的　研究早产儿畸变产物耳声发射 (distortionproductotoacousticemissions,DPOAE)幅值及检测通过率随孕龄 (postconceptionalage ,PCA)变化的趋势 ,探讨以耳蜗为主的外周听觉系统的发育过程。方法　PCA2 8～ 36周的早产儿 31人 (5 9耳 )和PCA37～ 4 1周的足月新生儿 19人 (35耳 )在出生后 3天～ 1周行DPOAE初测 ,对DPOAE初测未通过耳在 1周后进行复测 ,若复测未通过 ,于一周后再行复测 ,将全部测试结果按检测时PCA分成PCA <30周、PCA 30～周、PCA 32～周、PCA 34～周及PCA≥ 37周组 ,分析DPOAE幅值及通过率与检测时PCA的关系。结果　孕龄 <30周至 >37周 ,DPOAE通过率、各频率幅值呈现逐渐上升的趋势 ,且在孕龄 35周后趋于稳定。孕龄 <30周组通过率为 2 5 % ,≥ 37周组为 10 0 %。结论　外周听觉系统功能随PCA增加逐步完善 ,至PCA35周后发育趋于稳定 ,对PCA36周之前的早产儿行DPOAE检测时 ,其阳性结果 (未通过 )可能是生理性的 ,并非永久性听力障碍 ;早产儿的筛查时机宜选择理论上的PCA接近或达到足月的时间     

ABR和DPOAE在高胆红素血症新生儿听力筛查中的应用

目的探讨听性脑干反应(ABR)及畸变产物耳声发射(DPOAE)对高胆红素血症新生儿听力筛查的临床意义,为早期干预治疗提供依据.方法对170例高胆红素血症新生儿进行ABR和DPOAE检查,对其中部分异常者6个月后复查.结果 170例患儿中,ABR和DPOAE的总异常率分别为54.12%和32.65%;血清胆红素水平越高,ABR和DPOAE异常率越高(P<0.01),ABR异常越严重(P<0.01);胆红素浓度恢复正常后6个月复查ABR和DPOAE,恢复率分别为77.12%和77.01%,其中ABR异常DPOAE正常耳较两者均异常耳容易恢复(P<0.01).结论 ABR和DPOAE联合应用对高胆红素血症新生儿听力的早期定量定位评估比单独应用更准确和全面.     

Distortion Product Otoacoustic Emissions: A Normative Study

Distortion product otoacoustic emissions (DPOAEs) were quite recently introduced as a new objective auditory screening technique, having a unique potential because of their ability to analyze the micromechanical functions of the cochlea in a frequency-specific way. In 1992, Kemp and Bray released the commercially available Oto-dynamics Analyzer IL092, which enabled investigators and audiological centres to perform DPOAE measurements in different populations, but without any relationship to normative data. The purpose of this study was to describe the normative aspects of 2fl-f2 DPOAEs obtained with the IL092 from 101 normal ears of 101 healthy young adults. The DPOAEs were obtained automatically by means of two data-collection protocols on the IL092 in the form of DP-gram and DP-growth functions. These data were statistically processed to form a normative database which has the potential of serving as a basis for further research aimed at determining the utility of DPOAE testing in evaluating ear pathology     

Distortion Product Otoacoustic Emissions Evoked by Tone Complexes

Distortion product otoacoustic emissions (DPOAEs) are traditionally evoked by two-tone stimuli. In this study, emission data from Mongolian gerbils are reported that were obtained with stimuli consisting of six to 10 tones. The stimuli were constructed by replacing one of the tones of a tone pair by a narrowband multitone complex. This produced rich spectra of the ear canal sound pressure in which many of the third-order DPOAEs originated from the interaction of triplets of stimulus components. A careful choice of the stimulus frequencies ensured that none of these DPOAE components coincided. Three groups of DPOAEs are reported, two of which are closely related to DPOAEs evoked by tone pairs. The third group has no two-tone equivalent and only arises when using a multitone stimulus. We analyzed the relation between multitone-evoked DPOAEs and DPOAEs evoked by tone pairs, and explored the new degrees of freedom offered by the multitone paradigm.