Multiple-frequency Tympanometry Research Articles

Standard and multiple-frequency tympanometric norms in Chinese young and older adults

ABSTRACT The normative data of standard and multiple-frequency tympanometry should be established depending on gender, age, race and specific recording parameters. However, the lack of normative data of standard and multiple-frequency tympanometry was documented in Chinese older adults. Previous studies which conducted the normative data from Southern Chinese young adults may not represent the Chinese young and older adults in Taiwan. The purpose of this study is to establish the norms of standard and multiple-frequency tympanometry in Chinese young and older adults. The effects of age and gender are investigated for understanding the characteristics of normative data of tympanometry. A total of 100 young adults and 100 older adults with normal middle ear status were recruited from the community in Taiwan. The data of peak Ytm, Vea and TW were obtained by a 226 Hz probe tone. Multiple-frequency tympanometry was recorded by 226, 678 and 1000 Hz probe tones and categorized by the Vanhuyse model. The resonance frequency was obtained by the method of sweep-pressure. The two-way independent ANOVA was used separately to examine the effects of age and gender on each of the tympanometric measures. The effect of gender was found in Ytm, Vea and TW, while the effect of age was only found in Vea. Older adults have more complex patterns of multiple-frequency tympanometry and have significantly lower resonance frequency than young adults do. Results suggest that the middle ear system status changes with aging. The norms, especially gender-specific norms, are needed for Chinese older adults for interpretation.

Interaural Multiple Frequency Tympanometry Measures: Clinical Utility for Unilateral Conductive Hearing Loss

Tympanometry is a routine clinical measurement of the acoustic immittance of the ear as a function of ear canal air pressure. The 226 Hz tympanogram can provide clinical evidence for conditions such as a tympanic membrane perforation, Eustachian tube dysfunction, middle ear fluid, and ossicular discontinuity. Multiple frequency tympanometry using a range of probe tone frequencies from low to high has been shown to be more sensitive than a single probe tone tympanogram in distinguishing between mass- and stiffness-related middle ear pathologies (Colletti, 1975; Funasaka et al, 1984; Van Camp et al, 1986). In this study we obtained normative measures of middle ear resonance by using multiple probe tone frequency tympanometry. Ninety percent ranges for middle ear resonance and for interaural differences were calculated. In a mixed design, normative data were collected from both ears of male and female adults. Twelve male and 12 female adults with normal hearing and normal middle ear function participated in the study. Multiple frequency tympanograms were recorded with a commercially available immittance instrument (GSI Tympstar) to obtain estimates of middle ear resonant frequency (RF) using ΔB, positive tail, and negative tail methods. Data were analyzed using three-way mixed analyses of variance with gender as a between-subject variable and ear and method as within-subject variables. T-tests were performed, using the Bonferroni adjustment, to determine significant differences between means. Using the positive and negative tail methods, a wide range of approximately 500 Hz was found for middle ear resonance in adults with normal hearing and normal middle ear function. The difference in RF between an individual's ears is small with 90% ranges of approximately ±200 Hz, indicating that the right ear RF should be either 200 Hz higher or lower in frequency compared to the left ear. This was true for both negative and positive tail methods. Ninety percent ranges were calculated to determine the difference in middle ear resonance expected between an individual's ears. These ranges can provide critical normative values for determining how pathology in an ear with a unilateral conductive hearing loss is altering the mass or stiffness characteristics of the middle ear system.

Aural Symptoms in Patients With Temporomandibular Joint Disorders: Multiple Frequency Tympanometry Provides Objective Evidence of Changes in Middle Ear Impedance

Aural Symptoms in Patients With Temporomandibular Joint Disorders: Multiple Frequency Tympanometry Provides Objective Evidence of Changes in Middle Ear Impedance

Aural Symptoms in Patients With Temporomandibular Joint Disorders

The association of temporomandibular joint (TMJ) disorders with aural symptoms, such as tinnitus, otic fullness, and subjective decrease of hearing acuity, is a well-established clinical observation. Although several hypotheses have been made about the otic-conductive origin of these complaints, conventional 226-Hz tympanometry has failed to demonstrate any middle ear abnormalities. The aim of this study was to evaluate patients with TMJ disorders with multiple frequency tympanometry (MFT). Prospective clinical study. Outpatient clinic. The population of this study consisted of 40 patients with unilateral TMJ disorders diagnosed for longer than 1 month. After verifying that there were no abnormal otoscopic findings, 226-Hz tympanometry, conventional pure-tone audiometry, brainstem auditory evoked potentials, and MFT were performed. Resonant frequency (RF) values. With the exception of MFT, no abnormal audiologic findings were revealed. The ear ipsilateral to the lesion demonstrated significantly higher (p = 0.002) RF values in comparison to the contralateral ear. The difference in RF values was more obvious in patients aged 45 years or younger. The results of this study imply an increase in the stiffness of the middle ear, which has not been detected by conventional tympanometry. This represents the first concrete documentation of minor alterations in the conductive properties of the middle ear and seems to support the various hypotheses on the middle-ear origin of aural complaints in patients with TMJ disorders. Further studies are needed before a clear insight on the presumably multifactorial pathophysiology of these complaints can finally be reached.

Results of multiple-frequency tympanometry measures in normal and otosclerotic middle ears

Tympanometry is a non-invasive, quick, and inexpensive method for examining the middle-ear function. Its limited value in differentiating otosclerotic from normal middle ears caused researchers to develop new methods for evaluation of middle ears. Resonant frequency had been found to be higher in otosclerotic middle ears than normals. We conducted multiple-frequency tympanometry measurements in 25 surgically confirmed otosclerotic ears and 100 normal ears. Mean middle-ear resonant frequency for the otosclerotic group was found to be 1190 Hz and mean middle-ear resonant frequency of the control group was 934.6 Hz (p<0.001). With a cut off value of 1025 Hz (based on 95% confidence interval), sensitivity was 80% and specificity was 82%. The present findings confirm the advantage of the resonant frequency estimation over conventional tympanometry in detecting middle-ear status and mechanics in patients with otosclerosis. As a conclusion, detecting resonant frequency when evaluating patients for otosclerosis must be an essential part of examination. Nevertheless, further investigation is necessary for better diagnosis of otosclerosis preoperatively.

Multifrequency Tympanometry

We used multiple-frequency tympanometry (MFT) to evaluate the influence of a newly developed ossicular replacement prosthesis on transmission characteristics of middle ear. Multiple-frequency tympanometry is a technique for evaluating the emittance of the middle ear over a wide frequency range. It has been shown to be sensitive to certain middle ear conditions that are not detected by conventional 226-Hz tympanometry. In the field of experimental evaluation, MFT has been shown in certain animal studies to be useful in monitoring diseases. Thirty-six prostheses composed of titanium dioxide ceramic were implanted into the right middle ear of female rabbits. Bilateral measurements using conventional 226-Hz and MFT were performed before implantation and after 28, 84, and 300 days postoperatively. The results of the preoperative examinations yielded reference values for physiological resonance frequency. After dissecting the temporal bone, we opened the middle ear and analyzed both the surrounding tissue and the position of the prosthesis. The constant values for compliance revealed by both preoperative and postoperative measurements indicate good reproducibility of 226-Hz tympanometry. Postoperatively, resonance frequency increased continuously up to the 300th day. The observation supports the assumption that the higher stiffness level of connective tissue influenced resonance frequency. The reference values in this study can serve as guidelines for further experimental trials.

The Evolution of Aural Acoustic-Immittance Measurements

The Evolution of Aural Acoustic-Immittance Measurements

Tonic contractions of the tensor tympani muscle: a key to some non-specific middle ear symptoms? Hypothesis and data from temporal bone experiments

Conclusions. The results of this study show that in clinical practice it will not be easy to diagnose tonic contractions of the tensor tympani muscle and only a combination of findings will be helpful. Based on these experimental results a clinical study will be started which should clarify the diagnostic relevance of indicators of tonic tensor muscle contractions. Objectives. There are indications from the literature and from personal experience that tonic contractions of the tensor tympani muscle may play a role in some ear symptoms, such as fullness, certain cases of tinnitus, slight hearing loss or Ménière's disease-like findings. In order to prove this theory we looked for indicators, either visual or functional, to help clinically diagnose the functional state of the muscle, particularly its tonic contraction. Material and methods. Experiments simulating tensor contractions were carried out on temporal bone specimens. Traction was applied either to the isolated muscle, to its tendon or to the malleus neck. Effects were observed either visually via an endoscope or by impedance audiometry using multiple-frequency tympanometry. Results. During simulated tensor traction the aspect of the tympanic membrane changed slightly, i.e. there was some inward movement of the umbo. However, such effects were only identifiable during the pulling action or by directly comparing the “contracted” and “relaxed” states. Tympanometry revealed a decrease in the peak amplitudes and a shift in the middle ear resonance towards higher frequencies during contractions.

Multiple-frequency tympanometry in children with acute otitis media

Multiple-frequency tympanometry (MFT) is a sweep-frequency method of acoustic immittance measurement, recently introduced in clinical practice. It provides values for the resonant frequency of the middle ear system. The purpose of this study was to use MFT to collect information about the mechanoacoustical changes occurring to the middle ear system after acute otitis media and to compare it with the results of conventional, low probe-tone tympanometry. Children with acute otitis media were followed up with both methods for 1 month after an episode of acute infection. Also, children with normal hearing were studied to establish normative data. Resonant frequency of the middle ear was found to be lower than normal even 1 month past the initial episode, for all types of 226-Hz tympanograms. MFT seemed to record changes in the middle ear after acute otitis media that 226-Hz tympanometry was unable to detect, implying persistence of pathology. More extended research will illuminate the clinical value of this method in the follow-up of acute otitis media. (Otolaryngol Head Neck Surg 1999;121:797-801.)

Prognostic Value of Multiple-Frequency Tympanometry in Acute Otitis media

Multiple-frequency tympanometry (MFT) and conventional 226-Hz tympanometry were performed in 86 ears of children affected by acute otitis media (AOM) after therapy. In a 3-month follow-up period, the recurrence rate of AOM and persistence of middle-ear effusion in these children were evaluated in comparison with the early results of the two methods, as well as the relation of MFT findings to the possibility of development of AOM sequelae. It seems that abnormal resonant frequency values and recordings by MFT right after an episode of AOM indicate persistence of changes in the mass and stiffness balance of the middle ear, not demonstrated by conventional tympanometry, that could be responsible for a higher probability of AOM sequelae.

Middle ear mechanics in subjects with rheumatoid arthritis.

The incudo-malleolar and incudo-stapedial joints are true diarthroses and therefore may be subject to the same rheumatic lesions as any other articulation in the body. The existence of this involvement in rheumatoid arthritis (RA), however, is highly controversial. The present study investigates modifications of the mechanical properties of the middle ear in a group of subjects with RA by evaluating the resonance frequency obtained with multiple-frequency tympanometry (MFT). Thirty patients with RA, aged 20 to 68 years (mean age: 45.8 +/- 12.4 years), participated in the investigation. Their data were compared with those obtained in a control group of 48 age-matched subjects. Results obtained in both ears were examined in all subjects. The two groups displayed almost equal hearing levels with mean air conduction thresholds ranging from 10 to 22 dB HL. None of the subjects displayed an air-bone gap greater than 5 dB. Normal resonance frequency, calculated at the 95th percentile from the control group, ranged from 900 to 1250 Hz. Twelve rheumatoid arthritis patients (40 per cent) displayed abnormal resonance values. These findings were monolateral in 9 patients and bilateral in 3. Eleven out of 15 ears with abnormal multiple-frequency tympanometry data were characterized by an increase in resonance and 4 by a decrease. A correlation between abnormal resonance values and more aggressive RA was established. The results of this study suggest that rheumatoid arthritis may involve the incudo-malleolar and incudo-stapedial joints, altering the ossicular mechanics in response to static air pressure modifications. This does not impair sound conduction through the middle ear, but might reduce the protective mechanisms of the middle ear towards high static pressures.

Multiple-frequency tympanometry in children with otitis media with effusion.

Multifrequency tympanograms were recorded from 76 ears of 43 children affected by otitis media with effusion (OME) and 90 ears of normal-hearing children to obtain data for resonance frequency (RF) and changes in phase angle. There was found to be a statistically significant decrease (p < 0.01) in both RF values and change in phase angle in ears with OME compared to normative data. This decrease may be interpreted by considering OME as a mass pathology. Multiple-frequency tympanometry seems to be a useful method for determining the effect of various middle-ear pathologies on the mechano-acoustical status of the middle-ear system.

Multiple Frequency Tympanometry

Three methods for compensating multiple frequency acoustic admittance measurements for ear canal volume were studied in 26 men with normal middle ear transmission systems. Peak compensated static acoustic admittance (magnitude of y) and phase angle (phi) were calculated from sweep frequency tympanograms (226-1243 Hz in 113 Hz increments). Of the procedures used to compensate for volume in rectangular form, the ear canal pressure used to estimate volume had the largest effect on the estimate of middle ear resonance. Median resonance was 800 Hz for admittance measurements compensated at 200 daPa versus 1100 Hz for measurements compensated at -350 daPa. The remaining two methods, compensation of susceptance only versus both susceptance and conductance and compensation using the minimum volume versus separate volumes at each frequency, did not affect estimates of middle ear resonance. Estimates of middle ear resonance from compensated phase angle measurements also were compared with estimates of resonance from admittance and phase difference curves. Although resonance could not be estimated from the phase difference curve, resonance estimated from the admittance difference curve agreed with the estimate from compensated phase angle.

Mechanics of the middle ear in otosclerosis and stapedoplasty.

Seventy-three otosclerotic patients, 138 subjects who had undergone stapes surgery (50 total stapedectomies, 43 stapedotomies with stapedius tendon section and 45 stapedotomies with stapedius tendon preservation) and 70 normal controls were investigated by susceptance multiple frequency tympanometry. The aims were to evaluate the efficiency of this procedure in diagnosing otosclerosis and to assess the resonance properties of middle ears undergoing different types of stapedectomy. Tympanometry was performed using sweep frequencies ranging from 226 to 2,000 Hz for each pressure step of 12.5 daPa (pressure range from -500 to 400 daPa). The resonance frequency of the system was evaluated by identifying the "W" morphology of susceptance tympanograms. The results of the present investigation indicate that stapes surgery abnormally reduces the stiffness of the tympano-ossicular system. This phenomenon is limited by preservation of the stapedius tendon, which confers a significant degree of stiffness on the conductive system.

Basic Principles and Clinical Applications of Tympanometry

This article presents an overview of tympanometric measures using a 226-Hz probe tone, with an additional focus on complex admittance measures at 678 Hz and an introduction to multiple frequency tympanometry. Basic principles underlying all admittance measures are presented. The clinical implementation and interpretation of tympanometry is discussed.