多频率探测音声导抗测试

采用GSI－33中耳分析仪对正常40耳进行了多项指标的声导纳测试。分析了226，678，1000Hz三种探测音的鼓室导纳值，鼓室导纳图峰压点，梯度，外耳道容积，共振频率，相位角等，并对三种探测音所测各频率刺激声的声反射阈值，反射潜伏期，振幅指数，反射曲线图形进行了分析，旨在为较高频率探测音的声导抗测试提供正常值及理论依据。     

正常新生儿226Hz及1000Hz探测音鼓室导抗测试

探讨通过瞬态诱发耳声发射(TEOAE)筛查的正常新生儿低频（226Hz）及高频（1000Hz）探测音鼓室导抗图的特点、获得峰声导纳值等指标的正常值范围,为临床新生儿及婴幼儿中耳功能评估和诊断提供依据。方法采用中耳分析仪（GSI-33型）对足月顺产,并通过TEOAE筛查的正常新生儿分别进行低、高频探测音下的鼓室导抗测试,分析鼓室导抗图形态特征并对峰声导纳值等重要数据进行统计。结果在100例首次双耳通过TEOAE筛查的新生儿鼓室导抗测试中,低频鼓室导抗图以双峰型为主（占96%）,高频鼓室导抗图以单峰型为主（占90%）;低频探测音鼓室导抗图为双峰型而其高频探测音鼓室导抗图为单峰型的有174耳（占总耳数87%）;低频及高频探测音鼓室导抗图均为单峰型的仅有6耳（占总耳数3%）。结论正常新生儿低频探测音鼓室导抗图以双峰型为主,高频探测音鼓室导抗图以单峰型为主,应将两者结合来对新生儿及婴幼儿中耳功能进行评估;所获得相应的峰声导纳值、峰声导纳值处外耳道压力、外耳道容积等指标的正常值可以用于初步评估新生儿中耳功能状态。     

正常听力新生儿低频探测音鼓室导抗测试特点

目的:探讨瞬态诱发耳声发射(TEOAE)听力筛查通过的正常新生儿(2～7 d龄)低频(226 Hz)探测音鼓室导抗图的特点,获得外耳道容积,峰声导纳值等指标的特征.方法:采用AccuScreen Pro型TEOAE听力筛查仪对135名新生儿进行筛查;然后,采用GSI-33型中耳分析仪对首次双耳通过TEOAE听力筛查的新生儿进行低频探测音下的鼓室导抗测试,并获取鼓室导抗图、声导纳值和外耳道容积等相关数据.结果:135名新生儿中有105名新生儿首次双耳通过TEOAE听力筛查;在测得的鼓室导抗图中,双峰型202耳(占96.19%),单峰型8耳(占3.81%).双峰型鼓室导抗图第一峰的声导纳值为(0.91±0.18)mmho,峰声导纳值处外耳道压力为(18.02±12.26)daPa;第二峰的声导纳值为(1.05±0.23)mmho,峰声导纳值处外耳道压力为(-35.05±16.80)daPa;两峰间最低点处声导纳值为(0.74±2.57)mmho,其对应的外耳道压力为(0.37±7.61)daPa;外耳道容积(0.50±0.08)ml.结论:听力筛查通过的新生儿低频探测音鼓室导抗图以双峰型为主,相应的峰声导纳值、峰声导纳值处外耳道压力、外耳道容积等指标的正常值为临床新生儿中耳功能的评估提供了参考依据.     

足月正常新生儿多频探测音鼓室声导抗正常值测定

目的：探讨正常新生儿多频探测音鼓室声导抗图的图型、声导纳值、声纳值和声导值的正常范围。方法：使用GSI-33中耳分析仪,对足月顺产并通过瞬态诱发性耳声发射和畸变产物耳声发射筛查的新生儿55例（110耳）进行226、6781、000 Hz探测音鼓室声导抗测试,对比分析各种探测音鼓室声导抗的图形,声导纳值、声纳值和声导值,并进行统计学分析。结果：226 Hz探测音鼓室声导纳图、声纳图和声导图以双峰型为主,分别占90.0%、99.1%和85.5%,少数为单峰型,无多峰型出现;678 Hz探测音鼓室声导纳图、声纳图和声导图以单峰型为主,分别占62.7%、77.3%和62.7%,双峰型分别占34.6%、20.9%和31.8%,少数出现三峰型;1 000 Hz探测音鼓室声导纳图、声纳图和声导图以单峰型为主,分别占96.4%、99.1%和97.3%,极少数为双峰型,无三峰型出现。226 Hz与678 Hz探测音测试,鼓室声导纳值与声纳值、声纳值与声导值的均差异有统计学意义（均P〈0.05）;声导纳值与声导值差异无统计学意义（P〉0.05）。1 000 Hz探测音测试,鼓室声导纳值、声纳值与声导值的两两比较均差异有统计学意义（均P〈0.05）。结论：获得正常新生儿多频探测音鼓室声导抗图的图形、声导纳值、声纳值和声导值的正常范围,结果提示,1 000 Hz探测音鼓室声导抗测试可以较好反映正常新生儿的中耳功能。     

鼓室导抗测试法（下）

鼓室导抗测试法（下）钟乃川３．２．１声导纳图形应用６７８Ｈｚ探测音时，压力通常采用从正压至负压的变化方向，同时测试声纳及声导。通常可出现四种基本的正常图形（Ｖａｎｈａｙｓｅ等及ＶａｎＣａｍｐ等）［１］如图５。（１）１Ｂ１Ｇ每种成分仅有一个极值，即一个...     

正常新生儿高频探测音的鼓室导抗测试

目的探讨经瞬态诱发耳声发射(transient evoked otoacoustic emission,TEOAE)听力筛查通过的正常新生儿(2~7天龄)高频(1000Hz)探测音鼓室导抗图的特点。方法采用AccuScreen Pro型TEOAE听力筛查仪对135例新生儿进行听力筛查;对双耳通过TEOAE听力筛查的新生儿采用GSI-33型中耳分析仪检测在高频(1000Hz)探测音下的鼓室导抗图,对其进行分型,并分析外耳道容积、峰声导纳值等指标的正常值。结果135例新生儿中有100例(200耳)新生儿双耳通过TEOAE听力筛查,其鼓室导抗图单峰型有180耳(占90.0%)、双峰型5耳(占2.5%)、平坦无峰型7耳(占3.5%)、其它型8耳(占4.0%)。其中,单峰型鼓室导抗图的峰声导纳值为2.21±0.53mmHo,峰压点处外耳道压力为11.19±41.35daPa,外耳道容积约0.50±0.08ml。男性与女性相比:外耳道容积、峰声导纳值、 200daPa时的声顺值、峰补偿静态声导纳值的差异均有统计学意义(P<0.05);峰声导纳值对应的外耳道压力在性别中的差异无统计学意义(P>0.05)。结论通过听力筛查的新生儿高频(1000Hz)探测音的鼓室导抗图以单峰型为主,相应的峰声导纳值、峰压点处外耳道压力、外耳道容积等指标的正常值可以作为新生儿中耳状态评估时的参考依据。     

0-12月龄婴幼儿不同频率声导抗测试研究

目的分析0~12月龄听力正常婴幼儿226Hz、678Hz和1000Hz探测音声导抗测试的结果,探讨不同频率探测音声导抗鼓室图在评价该年龄段婴幼儿中耳功能中的作用。方法 200例0~12月听力正常婴幼儿分成4组,每组50例:新生儿期(0~28d)、1~3月龄(±3d)、4~6月龄(±7d),7~12月龄(±7d),用GSI Tymp Star 2型中耳分析仪对200例(400耳)均行226Hz、678Hz和1000Hz探测音声导抗测试,分析不同年龄组婴儿、不同频率鼓室探测音声导抗图形的特点。结果 1226Hz探测音测试时,外耳道容积随着年龄的增大而增大,最大的压力峰值和声顺值随年龄增大而减小2678Hz和1000Hz探测音测试时,1~3月年龄段组的最大的压力峰值和声顺值为最小,其余年龄段组最大的压力峰值和声顺值随年龄增大而增大。相同年龄段组1000Hz鼓室探测音给声时所得最大的压力峰值和声顺值均大于678Hz鼓室探测音给声时所得最大的压力峰值和声顺值。3频率和年龄的因素对鼓室图的导纳最大的压力峰值和声顺值都有显著影响。4中耳共振频率分别为:新生儿期(0~28d)为(284±48)Hz,1~3月龄组为(293±51)Hz,4~6月龄组为(450±152)Hz,7~12月龄组为(650±205)Hz。结论在评估0~6个月婴幼儿中耳功能时,应使用1000Hz探测音声导抗,在1000Hz探测音声导抗测试出现堵塞效应时,可使用678Hz探测音做补充,7-12个月婴幼儿使用226 Hz鼓室图探测音时最好同时使用1000Hz探测音做声导抗测试,不同年龄段婴幼儿应使用不同频率的探测音以及其正常值以便于准确了解婴幼儿的中耳状态。     

鼓膜小穿孔的鼓室图改变

鼓室图有助于评价各种耳病的鼓室状态。一般来说,鼓膜穿孔由于对外耳道压力变化缺乏顺应性反应,鼓室图曲线几乎成一直线。著者采用220Hz探测音作阻抗测试,外耳道压力以35mmH_2O/S速度变化行双向描记,获得二种具有特征性鼓室导抗曲线。第一种称峰值偏移型,是指正向描记外耳道压力渐增时,在鼓室图负压区形成声顺峰值,反之,负向描记外耳道压力渐减时,在正压区形成声顺峰值。压力变化越     

正常婴儿1000Hz探测音及多频率扫描声导纳测试分析

目的分析正常婴儿1000 Hz探测音及多频率扫描声导纳检测的临床特征。方法对164例正常听力婴儿（250耳）的1000 Hz探测音声导纳图,用基线法分型并测量正峰声导纳值;通过声纳差（ΔB）-频率函数曲线和相位角差（Δθ）-频率函数曲线检测中耳共振频率。运用SPSS11.0软件,分年龄段分别统计正峰声导纳、共振频率和相位角差（Δθ）的平均值、标准差、中位数、5%分位数、95%分位数及95%置信区间。结果全部样本均可测得基线上正峰声导纳值,各年龄组的5%分位数均≥0.2 mmho;各年龄组共振频率从311.01～599.06 Hz递增,相位角差（Δθ）的绝对值平均值从44.52～22.84递减。结论高频率探测音声导纳检测和多频率扫描声导纳检测,充分反映婴儿中耳声学特性的转变过程,更适用婴儿的中耳功能评估。     

低频和高频探测音鼓室声导抗测试在婴儿中耳功能诊断中的作用

目的评价低频和高频探测音鼓室声导抗测试在诊断婴儿中耳功能异常中的作用。方法使用GSI Tympstar中耳分析仪，对年龄5—25周的听性脑干反应（auditory brainstem response，ABR）检查正常婴儿15例（30耳）和Ⅰ波潜伏期延长提示可能存在中耳功能异常婴儿17例（20耳），进行226、678、1000Hz探测音鼓室声导抗测试的比较。结果226Hz探测音鼓室声导纳图的静态声导纳值、图形、峰压和梯度在2组间的差异无统计学意义。678Hz探测音鼓室声导纳图、声纳图及声导图在2组中均可见无峰型、单峰型、双峰型、三峰型图形，其与ABR检查的一致率分别为70．0％、58．0％、64．0％，kappa值分别为0．324、0．234、0．118。1000Hz探测音鼓室声导纳图、声纳图及声导图在正常组中单峰型分别为28耳（93．3％）、25耳（83．3％）、26耳（86．7％），在异常组中无峰型分别为15耳（75％）、17耳（85％）、13耳（65％），其与ABR的一致率分别为90．0％、92．0％、86．0％，kappa值分别为0．783、0．831、0．690。结论1000Hz探测音鼓室声导抗测试是诊断小于25周婴儿中耳功能的较准确的检查方法，226、678Hz探测音鼓室声导抗测试则不能提供这些婴儿中耳功能的准确的信息。     

Dynamic Behavior of the Middle Ear Based on Sweep Frequency Tympanometry

A measuring apparatus was developed; its probe tip, which exhibits flat frequency characteristics, enables this apparatus to measure the absolute sound pressure and absolute phase variations versus both sweeping frequency and external auditory canal pressure. Although it is difficult to diagnose ossicular chain separation and fixation from the commonly used tympanograms with a low probe tone frequency (e.g. f = 220 Hz), the results obtained with this apparatus enable one to clearly distinguish patients with ossicular chain disorders from normal subjects. Therefore, it seems to be highly useful in the clinical diagnosis of ossicular chain disorders.     

Sweep-frequency tympanometry: its development and diagnostic value

This reports a newly developed tympanometric system using a sweep-frequency probe tone. For a sweep-frequency tone ranging from 220 to 2 000 Hz, measurements of sound pressure (P) and phase were performed at ear canal pressures of 0 and -200 mm H2O. The results were expressed as a sound pressure curve (P0-P-200 in decibels), a phase curve (formula: see text) and a polar curve (formula: see text) against probe tone frequency. Both the frequency at which the sound pressure curve crossed the 0-dB difference line and the peak frequency of the phase curve shifted lower than normal for ossicular disruption and higher than normal for ossicular fixation. Changes in the sound pressure curve and in the phase curve were exaggerated for ossicular disruption and limited for fixation. As the result of these, the polar curve showed an expanded type for disruption and a compressed type for fixation. A review of 220-Hz tympanograms and of the polar curves for 10 patients demonstrated that the latter permitted a better discrimination among ossicular disorders.     

Clinical study on sweep-frequency tympanometry--data analysis using principal component analysis

A sweep-frequency tympanometer has been developed to diagnose auditory ossicular lesions more precisely. This device measures acoustic middle ear features by changing the probe tone frequency continuously. The oscillator sweeps frequency of the probe tone from 200 to 2,500Hz 1.5 seconds. A microphone picks up the changes in the acoustic pressure and the phase in the external auditory meatus during the frequency change of the probe tone. These measurements are performed under pressures at -200 and 0 dapa, and differences of both the acoustic pressure and the phase between these two pressures are graphically displayed using a microcomputer. This device can also measure and digitally display the frequency (BHz) and the sound pressure (BdB) at the minimum point (B) of the sound pressure curve, the frequency (ZHz) at 0 crossing point (Z) of the sound pressure curve, and the frequency (PHz) and the phase difference (Pdeg) at the maximum point (P) of the phase curve. Normal ranges of these five values were obtained to establish diagnostic criteria from 200 normal ears. The normal values were as follows: BHz, 480 to 1,070Hz; BdB, -6.0 to -1.8dB; ZHz, 1,100 to 1,860Hz; PHz, 910 to 1,820Hz; and Pdeg, 16.3 to 47.9 degrees. Eight cases of ossicular dislocation and 14 cases of ossicular fixation, all of which had normal external auditory meatus and tympanic membrane, were evaluated based on these values. All the cases with ossicular dislocation and 12 cases out of 14 with ossicular fixation were correctly diagnosed.(ABSTRACT TRUNCATED AT 250 WORDS)     

Standard and multifrequency tympanometric norms for Caucasian and Chinese young adults

OBJECTIVE: This study examined differences between a group of normal-hearing Caucasian and Chinese young adults on six tympanometric parameters. The goal of this study was to determine if the Chinese group had different low and multifrequency tympanometry results than the Caucasian group. DESIGN: There were a total of 159 subjects (303 ears) between the ages of 18 and 34 years, with 76 subjects in the Caucasian group and 83 subjects in the Chinese group. Tympanometric data were gathered on a clinical immittance machine, the Virtual 310 equipped with a high frequency option. Four of the parameters-static admittance (SA), tympanometric width (TW), tympanometric peak pressure (TPP), and ear-canal volume (ECV)-were measured automatically at a standard 226 Hz frequency. The remaining two parameters-resonant frequency (RF) and SA up to 1,200 Hz-were measured by multifrequency, multicomponent tympanometry, using a mathematical approach. RESULTS: The Chinese group had significantly lower SA, wider TW, more positive TPP, and lower ECV than their Caucasian counterparts. The parameter of SA up to 1,200 Hz showed a significant group effect (Caucasian versus Chinese) until 900 Hz in the male group and up to 1,120 Hz in the female group. The Chinese group had significantly higher RF than the Caucasian group. Once the effect of body size was compensated by adjusting for the ear canal and the middle ear volumes, the differences observed between the Caucasian and the Chinese groups were no longer significant for tympanometric parameters obtained at standard probe tone frequency of 226 Hz; however, the effect was still significant for SA obtained at higher probe tone frequencies (560, 630, 710, 800, and 900 Hz) and for RF. Applying the Caucasian norms to a group of mainly Caucasian adults with surgically confirmed otosclerosis resulted in improved overall test performance when compared with the combined Caucasian and Chinese norms and the Chinese only norms. CONCLUSIONS: It seems that the body size plays a crucial factor in the observed differences between the Caucasian group and Chinese groups at a standard probe tone frequency of 226 Hz; however, other mechano-acoustical properties of the middle ear may contribute to these differences at higher probe tone frequencies. Findings of this study suggest that further research is needed to investigate the effects of body size on immittance measures with other ethnic groups. In the meantime, overall test performance may be improved by using a more homogenous norm when testing the Caucasian or Chinese individuals.     

Differential effects of ear-canal pressure and contralateral acoustic stimulation on evoked otoacoustic emissions in humans.

The effect of ear canal pressure variation (ECPV) on click evoked otoacoustic emissions (EOAEs) was compared to the suppressive effect observed with contralateral acoustic stimulation (CAS) in 11 healthy subjects. Both total EOAE amplitude and amplitude of 200 Hz frequency bands (22) were analyzed. Our results revealed that the ECPV as the CAS induced a decrease of the total EOAE amplitude; these two factors showed an additive effect when they are conjoint. The study of the EOAE frequency bands showed that the majority of them decreased under CAS and ECPV; however, a few bands are not affected. Moreover, it appeared that amplitude of the EOAE frequency bands were not modified in a similar way between the two factors: indeed some bands around 4.1 kHz did not decrease either by CAS or ECPV. These results suggest that these applied factors exert different actions on EOAEs. Moreover, the lack of a decrease effect for the same bands, both with CAS and ECPV, may explain the vulnerability of some cochlear locations.     

Tympanometry using a sweep-frequency probe tone and its clinical evaluation

In this new tympanometric system, air pressure in the external meatus is kept constant at either -200 daPa or 0 daPa. The frequency of the probe tone is swept from 220 to 2,000 Hz (or 2,500 Hz, if necessary) in 4 s. During this frequency sweep, sound pressure in decibels and phase angle in degrees in the external meatus are sampled and the differences in sound pressure and phase angle measured at -200 and 0 daPa pressures are computed. These results are figured as a frequency-sound pressure curve and a frequency-phase angle curve. From the study on 8 fresh human cadaver temporal bones, four parameters in these curves are selected by discriminant analysis to provide diagnostic criteria: the minimum value and the 0-cross frequency of the frequency-sound pressure curve and the maximum value and its frequency of the frequency-phase angle curve. Normal parameters were determined in 50 normal ears. Evaluation of 40 patients with ossicular disorders revealed that 10 out of 12 cases of ossicular discontinuity and 5 out of 6 cases of malleus and/or incus fixation were correctly diagnosed. For stapes fixation, the diagnosis was correct in 12 out of 22 ears. This system is useful in the clinical diagnosis of ossicular disorders, producing a collection of curves and parameters that are distinctively different for the ossicular discontinuity and the ossicular fixation.     

Sweep-Frequency Tympanometry: Its Development and Diagnostic Value

This reports a newly developed tympanometric system using a sweep-frequency probe tone. For a sweep-frequency tone ranging from 220 to 2 000 Hz, measurements of sound pressure (P) and phase (Θ) were performed at ear canal pressures of 0 and -200 mm H₂0. The results were expressed as a sound pressure curve (P₀-P_-200 m decibels), a phase curve (Θ₀-Θ_-200 in degrees) and a polar curve (P₀-P_-200, Θ₀-Θ_-200) against probe tone frequency. Both the frequency at which the sound pressure curve crossed the 0-dB difference line and the peak frequency of the phase curve shifted lower than normal for ossicular disruption and higher than normal for ossicular fixation. Changes in the sound pressure curve and in the phase curve were exaggerated for ossicular disruption and limited for fixation. As the result of these, the polar curve showed an expanded type for disruption and a compressed type for fixation. A review of 220-Hz tympanograms and of the polar curves for 10 patients demonstrated that the latter permitted a better discrimination among ossicular disorders.     

An update on the external ear resonance in infants and young children

The diffuse field to ear canal sound pressure transformations determined for 26 children (34 ears) from birth to 3 years old, confirm the earlier findings [Kruger B. Ruben RJ. Acta Otolaryngol (Stockh) 1987; 103:578-85] that the external ear fundamental resonance frequency is significantly higher at birth (about 6 kHz), and decreases with age to adult values (2.7 kHz) by the second year. The transformations were measured with either single or double probe tubes (coupled to miniature microphones) that were placed in the ear canal of sleeping infants. The accuracy of the magnitude of the transformations is discussed. Previously reported implications for hearing aid selection are supported.     

Stapes Vibration in the Chinchilla Middle Ear: Relation to Behavioral and Auditory-Nerve Thresholds

The vibratory responses to tones of the stapes and incus were measured in the middle ears of deeply anesthetized chinchillas using a wide-band acoustic-stimulus system and a laser velocimeter coupled to a microscope. With the laser beam at an angle of about 40 ° relative to the axis of stapes piston-like motion, the sensitivity-vs.-frequency curves of vibrations at the head of the stapes and the incus lenticular process were very similar to each other but larger, in the range 15–30 kHz, than the vibrations of the incus just peripheral to the pedicle. With the laser beam aligned with the axis of piston-like stapes motion, vibrations of the incus just peripheral to its pedicle were very similar to the vibrations of the lenticular process or the stapes head measured at the 40 ° angle. Thus, the pedicle prevents transmission to the stapes of components of incus vibration not aligned with the axis of stapes piston-like motion. The mean magnitude curve of stapes velocities is fairly flat over a wide frequency range, with a mean value of about 0.19 mm^.(s Pa⁻¹), has a high-frequency cutoff of 25 kHz (measured at −3 dB re the mean value), and decreases with a slope of about −60 dB/octave at higher frequencies. According to our measurements, the chinchilla middle ear transmits acoustic signals into the cochlea at frequencies exceeding both the bandwidth of responses of auditory-nerve fibers and the upper cutoff of hearing. The phase lags of stapes velocity relative to ear-canal pressure increase approximately linearly, with slopes equivalent to pure delays of about 57–76 μs.