Bone Conduction Audiometry Research Articles

Inner ear function in children with Fabry disease.

The prevalence of hearing loss in patients with Fabry disease is still uncertain. This paper examines hearing loss in a group of young patients with Fabry disease. A clinical ear nose and throat examination, pure-tone air and bone conduction audiometry, speech audiometry and middle ear testing (tympanometry and acoustic reflex testing) were carried out in four girls and two boys with Fabry disease (age, 7-17 years), receiving enzyme replacement therapy (ERT). None of the patients complained of a hearing disorder or suffered from hearing loss. Three female patients reported tinnitus; however, this was not reported as being a problem. One boy reported tinnitus for the first time during 6 months of ERT. Based on this small sample of patients, it appears that the hearing disorders associated with Fabry disease develop mainly in adulthood. Tinnitus may be an earlier symptom than previously thought in Fabry disease.

The 5-year incidence and progression of hearing loss: the epidemiology of hearing loss study.

Hearing impairment affects many older adults, but the incidence is unknown. To determine the 5-year incidence and progression of hearing impairment. A longitudinal, population-based study of adults aged 48 to 92 years at baseline examination. Hearing sensitivity was measured twice, 5 years apart. Testing was conducted at the Beaver Dam Community Hospital, Beaver Dam, Wis. A total of 1636 participants without hearing loss and 1085 participants with hearing loss at the baseline examination in 1993-1995 were reexamined in 1998-2000. The examinations included otoscopy, screening tympanometry, and tone air- and bone-conduction audiometry. Incidence of hearing impairment was defined as a pure-tone average (PTA) of thresholds at 500, 1000, 2000, and 4000 Hz (PTA 0.5, 1, 2, and 4 kHz) greater than 25 dB HL (hearing level) in either ear at follow-up among those without hearing loss at baseline. Progression was defined as a change of more than 5 dB in the PTA 0.5, 1, 2, and 4 kHz among those with hearing loss at baseline. The 5-year incidence of hearing impairment was 21%. More than half of those with hearing loss at baseline experienced a decline in hearing. Age was an important risk factor for both incidence and progression. Male sex, occupation, and education were associated with the incidence of hearing loss after adjusting for age. Older adults have a high risk of developing hearing loss. Among those with hearing loss, most experience further declines in hearing sensitivity over time. These data indicate that hearing impairment is an important public health problem and underscore the need for appropriate hearing screening and treatment.

A longitudinal study of the association between tooth loss and age‐related hearing loss

The purpose of this study was to investigate cross-sectional and longitudinal associations between hearing acuity and tooth loss in 1156 US veterans taking part in the Veterans Affairs' Normative Aging (NAS) and Dental Longitudinal (DLS) Studies in the Boston, MA, area. The mean age was 48 years (SD = 8.9), 5.3% were edentulous, and 15.4% had < 17 teeth at baseline. Hearing acuity was determined by puretone, air- and bone-conduction audiometry, and speech discrimination tests at triennial examinations over a 20-year follow-up period. Hearing decline was defined as a change from baseline in the average puretone air-conduction thresholds of > or = 20 dB at 0.25, 0.5, 1, 2, 3, 4, 6, and 8 kHz. The explanatory variables of interest were change since baseline in dentate status (cut points at < 1, < 17, and < 20 teeth), and in the number of teeth lost (linear). Linear and logistic regression models--which controlled for baseline audiological status, age, air-bone gap, and otoscopic examination at current visit--showed that subjects who went from having > or = 17 to < 17 teeth had 1.64 times (95% CI, 1.24-2.17) as high odds of having hearing decline as those with no change in their dentate status. For every tooth lost since baseline, there was a 1.04 times as high odds (95% CI, 1.02-1.06) for hearing decline, when additional baseline and time-varying covariates were taken into account in the model.

Carhart notch effect in otosclerotic ears measured by electric bone-conduction audiometry.

The Carhart notch is an elevation in the middle-frequency bone-conduction threshold of an ear with clinical otosclerosis. The study population consisted of 138 patients with clinical otosclerosis. Conventional air-conduction (AC) and bone-conduction (BC) and electric bone-conduction (EBC, with Audimax 500 audiometer) thresholds were measured 2 weeks before and 7 months after stapes surgery. The EBC thresholds were converted from mA values to dB SPL to compare the results obtained with the different methods. The mean differences in the BC thresholds before and after the operation were 3.2 dB (95% CI 1.9-4.6) at 1 kHz and 7.6 dB (95% CI 6.1-9.1) at 2 kHz. The mean differences in the EBC thresholds were 5.4 dB (95% CI 3.8-6.9) at 1 kHz and 5.3 dB (95% CI 3.4-7.1) at 2 kHz. Thus, both methods showed a distinct Carhart notch effect.

Moderate alcohol consumption and hearing loss: a protective effect.

To determine if moderate alcohol consumption is associated inversely with hearing loss in a large population based study of older adults. Cross-sectional population based cohort study. Data are from the 1993-1995 examinations for the population based Epidemiology of Hearing Loss Study (EHLS) (n = 3571) and the Beaver Dam Eye Study (BDES) (n = 3722). Midwestern community of Beaver Dam, Wisconsin. Residents of Beaver Dam aged 43 to 84 in 1987-1988 were eligible for the BDES (examinations in 1988-1990 and 1993-1995). During 1993-1995, this same cohort was eligible to participate in the baseline examination for the EHLS. Hearing thresholds were measured by pure tone air and bone conduction audiometry (250-8000 Hz.). History of alcohol consumption in the past year, heavy drinking (ever), medical history, occupation, noise exposure, and other lifestyle factors were ascertained by a questionnaire that was administered as an interview. In multiple logistic regression analyses controlling for potential confounders, moderate alcohol consumption (>140 grams/week) was inversely associated with hearing loss (PTA(.5,1,2,4 > 25 dB HL); odds ratio [OR] = .71, 95% confidence interval [CI] = .52, .97; where PTA is pure tone average). A similar association was found for moderate hearing loss (PTA(.5,1,2,4 > 40 dB HL); OR = 0.49, 95% CI = 0.32, 0.74). Alcohol consumption was associated inversely with the odds of having a low frequency hearing loss (OR = 0.61) or a high frequency hearing loss (OR = 0.60). These findings did not vary significantly by age or gender. There was an increase in the odds of having a high frequency hearing loss (OR = 1.35, 95% CI = 1.04, 1.75), in those with a history of heavy drinking (> or =4 drinks/day). Including cardiovascular disease or its related factors did not significantly attenuate the protective effect. There is evidence of a modest protective association of alcohol consumption and hearing loss in these cross-sectional data. This finding is in agreement with a small body of evidence suggesting that hearing loss is not an inevitable component of the aging process.

Comparison of argon and CO2 laser stapedotomy in primary otosclerosis surgery

Purpose: The primary use for the laser in otosclerosis surgery is to create a stapes footplate fenestration that obviates the need for mechanical footplate removal. Experimental studies that evaluate the potential safety of visible (argon and potassium-titanyl-phosphate [KTP]) and invisible (CO2) light laser systems in stapes surgery report conflicting results. The purpose of this study is to compare the clinical safety and efficacy of the CO2 and argon laser systems when used for primary laser stapedotomy. Materials and Methods: A retrospective case review of 124 primary laser stapedotomies using either the argon (n = 59) or CO2 (n = 65) laser was performed. Data consisted of pre- and postoperative air and bone conduction audiometry, speech discrimination scores (SDS), intraoperative findings, and postoperative complications. Between group differences (argon v CO2) were sought using standard statistical methodology. Results: The argon and CO2 laser groups were comparable with regards to age, sex, preoperative air-bone gap, and laterality. Mean preoperative air and bone conduction pure-tone average (PTA) and SDS were somewhat higher in the CO2 laser group (P <.05). Postoperatively, both groups showed similar results in mean change in air conduction PTA, air-bone gap, and SDS, as well as in the frequency of complications. There were no anacoustic ears in either group. Conclusions: The results suggest that the argon and CO2 laser systems are comparable with regards to safety and efficacy when used by experienced surgeons for stapedotomy. (Am J Otolaryngol 2000;21:227-230. Copyright © 2000 by W.B. Saunders Company

Systematic errors in bone conduction audiometry.

Air and bone conduction audiometry was carried out on two separate groups of 12 normal hearing volunteers. One group was tested at St Mary's hospital, the other at Charing Cross hospital. The results from both centres showed evidence of a systematic error in bone conduction resulting in a pattern of 'notching' at 2 kHz. We argue that the effect is likely to be more apparent in conductive deafness and that a significant distortion of the audiogram occurs in about 17% of such cases. Since the problem appears not to be restricted to the centres involved in the study, we strongly recommend that the issue be addressed by the appropriate professional bodies.

Association of NIDDM and hearing loss.

To evaluate the association of NIDDM with hearing loss in a large population-based study. Data from population-based longitudinal studies of aging conducted in Beaver Dam, Wisconsin, were used in these analyses. Hearing thresholds were determined by pure-tone air- and bone-conduction audiometry performed by trained technicians following American Speech-Language-Hearing Association specifications. Hearing loss was defined as the pure-tone average of the frequencies 500, 1,000, 2,000, and 4,000 Hz greater than 25 decibels hearing level in the worse ear. Diabetes status was determined by self-report of physician-diagnosed diabetes or by elevated glucose or glycated hemoglobin levels at examination. Of 3,571 study participants, 344 were classified as having NIDDM. Subjects with NIDDM were more likely to have a hearing loss than were subjects without diabetes (59 vs. 44%). After results were adjusted for age, this difference was not statistically significant. After individuals with hearing loss patterns inconsistent with presbycusis were excluded, there was an association between NIDDM and hearing loss when controlling for potential confounders (odds ratio [OR] 1.41, 95% CI 1.05-1.88). There was no association between duration of diabetes or glycemic control and hearing loss. Individuals with NIDDM and nephropathy were more likely to have a hearing loss than were those with NIDDM but no nephropathy (OR 2.28, 95% CI 1.04-5.00). These data are suggestive of a weak association between NIDDM and hearing loss.

Cigarette smoking and hearing loss: the epidemiology of hearing loss study.

Clinical studies have suggested that cigarette smoking may be associated with hearing loss, a common condition affecting older adults. To evaluate the association between smoking and hearing loss. Population-based, cross-sectional study. Community of Beaver Dam, Wis. Adults aged 48 to 92 years. Of 4541 eligible subjects, 3753 (83%) participated in the hearing study. The examination included otoscopy, screening tympanometry, and pure-tone air-conduction and bone-conduction audiometry. Smoking history was ascertained by self-report. Hearing loss was defined as a pure-tone average (0.5, 1, 2, and 4 kHz) greater than 25-dB hearing level in the worse ear. After adjusting for other factors, current smokers were 1.69 times as likely to have a hearing loss as nonsmokers (95% confidence interval, 1.31-2.17). This relationship remained for those without a history of occupational noise exposure and in analyses excluding those with non-age-related hearing loss. There was weak evidence of a dose-response effect. Nonsmoking participants who lived with a smoker were more likely to have a hearing loss than those who were not exposed to a household member who smoked (odds ratio, 1.94; 95% confidence interval, 1.01-3.74). These data suggest that environmental exposures may play a role in age-related hearing loss. If longitudinal studies confirm these findings, modification of smoking habits may prevent or delay age-related declines in hearing sensitivity.

Tentative age-related norms for high frequency electric bone conduction audiometry

From 172 male and female patients aged 7-71 years old and admitted in one month to a tuberculosis hospital, 150 had their highest audible electric bone conduction (EBC) frequency evaluated, prior to the commencement of any medical treatment. Various problems in establishing high frequency norms are discussed and from the results of this study tentative age-related highest frequency EBC norms are suggested. Possible clinical applications of evaluating the highest audible EBC frequency is suggested.

Carhart Notch and Electric Bone-conduction Audiometry

The Carhart notch is a depression in the bone-conduction audiogram of patients with clinical otosclerosis. The middle frequencies from 0.5 to 2 kHz, which correspond to the resonance frequency of the middle ear, can be substantially improved following successful stapes surgery. Twenty-nine consecutive patients with clinical otosclerosis were tested 2 weeks before and 7 months after stapes surgery with conventional air-conduction (AC) and bone-conduction (BC) audiometry and electric bone-conduction (EBC) audiometry using an Audimax 500 audiometer. The BC thresholds improved at 0.5-2.0 kHz corresponding to the Carhart notch. On average, the EBC thresholds remained more stable, showing no Carhart phenomenon, which supports the concept that EBC stimulation is not entirely equivalent to conventional BC audiometry, but has a different mode of action on the inner ear.

Background noise in rooms used for pure-tone audiometry in disability assessment.

Background noise limits for audiometry are determined by the effects of masking and are specified in international standards. The standards provide for audiometric testing over a range of audiometric frequencies extending down to 500 Hz or lower. The lowest frequency of testing is an important factor determining the admissible noise, and for certain applications it is appropriate to consider the limits applicable to testing over a more restricted range. Assessment of hearing disability in the UK is generally based on a consideration of pure-tone hearing threshold levels in the frequency range 1 kHz upwards. A modification of the standardized noise limits is proposed which allows some relaxation appropriate to this higher minimum frequency. For air-conduction audiometry, these modifications affect only the permissible background noise in the frequency range below 1 kHz. Where bone-conduction audiometry is required in order to quantify a conductive component of the hearing loss, the measurements need to be made on both ears with the non-test ear masked in both cases; the external background noise will thus only be heard monaurally and this justifies a correction to the noise limits compared with those appropriate to bone-conduction audiometry without masking.

The limited accuracy of bone-conduction audiometry: its significance in medicolegal assessments

Accurate bone-conduction testing with masking is always difficult, but for clinical purposes limited accuracy suffices. However, when assessing claimants for compensation, extreme care is needed since even small apparent air-bone gaps are sometimes translated into financial abatement. This paper sets out the stringent test conditions required to achieve adequate precision. It also indicates the inaccuracies inherent in such tests, and recommends procedures for interpreting the significance of bone-conduction thresholds.

High-Frequency Air-Conduction and Electric Bone-Conduction Audiometry: Age and Sex Variations

208 subjects representing both sexes and five age groups (15-70 years) were examined to obtain age-related threshold values for high-frequency (HF) electric bone-conduction (EBC) audiometry. The measurements also included conventional pure-tone audiometry and air-conduction (AC) HF (8-18 kHz) audiometry. The measured EBC thresholds were comparable to the values obtained with AC audiometers, and were equal to ISO standards at the frequencies of 0.5-6 kHz. The 15- and 20-year-old groups' EBC thresholds at 8 kHz were equivalent to thresholds of 15-year-old people from a cross-sectional material in Northern Finland. Thresholds deteriorated as a function of age, particularly in the HF range. The males had poorer thresholds than the females, especially in the age groups of 40 and 60 years. This could be attributed mainly to their greater noise exposure. The EBC method is quite practical and reliable for routine clinical measurements, but the dynamic range of the audiometer limits its use to relatively young subjects.

High-Frequency Air-Conduction and Electric Bone-Conduction Audiometry: Comparison of Two Methods

Threshold values for 147 subjects (9-43 years old) were measured with a high-frequency (HF) air-conduction (AC) (Interacoustics AS 10 HF) and an electric bone-conduction (EBC) (Audimax 500) audiometer. In addition, the reproducibility of these methods was studied in another group of 24 subjects. The results confirmed the previous findings of Okstad et al. (1988) that the electric current (i) used as a stimulus in the Audimax 500 audiometer can be converted into decibels with a correction factor of 40 log (i) re 1 mA as Tonndorf & Kurman (1984) have proposed. However, an additive frequency-dependent correction is needed to obtain similar loudness sensation increases with these audiometers. Reproducibility with the EBC audiometer was better than with the AC audiometer, especially in the HF range.

Bone conduction thresholds for different mastoid placement sites

Bone conduction thresholds were obtained from 250 to 4000 Hz by placing the bone vibrator on the mastoid as done for audiometry and at mastoid sites initially judged to produce the loudest perception of a 250-, 500-, and 1000-Hz pure tone and white noise using 30 normally hearing adult subjects. The bone conduction thresholds were found to be variable across placement sites and test frequencies. However, the placement site judged to be the loudest with white noise generally resulted in the lowest thresholds. Implications for bone conduction audiometry, including normal air-bone gaps, and reference equivalent threshold force levels will be discussed.

骨導聴力検査におけるマスキング困難例の検討

骨導聴力検査におけるマスキング困難例の検討

Natural History vs. Surgery for Meniere's Disease

Menière's disease has an episodic course, and certain patients undergo spontaneous remission of their vertigo. A retrospective study of patients treated from 1974 to 1983 was undertaken to evaluate the long-term outcome of patients with Menière's disease for whom surgery was recommended, comparing those who had a surgical procedure with a similar group of patients who declined surgery. The surgical procedures performed were endolymphatic subarachnoid shunt (ELS), retrolabyrinthine vestibular neurectomy (RVN), middle fossa vestibular neurectomy (MFVN), and transmeatal cochleo-vestibular neurectomy (CVN). We used a questionnaire, made up according to the 1985 American Academy of Otolaryngology (AAO) criteria, for reporting results for Menière's disease treatment, and compared patients who were offered surgery but declined (N = 50) with those who underwent surgery (N = 83). The data were analyzed statistically. Initial evaluation, which included air and bone conduction audiometry, speech discrimination, electronystagmography (ENG), frequency of vertigo attacks per month, and disability, showed both groups to be comparable at the outset. Of the non-operated group 57% had complete control of vertigo at 2 years; 71% had complete control after an average of 8.3 years. After an ELS, 40% of patients had complete control of vertigo after 2 years; 70% had complete control after an average of 8.7 years. After a neurectomy (RVN or CVN), 93% had complete control of vertigo (average followup, 4.4 years). These results indicate statistically that the ELS procedure does not alter the long-term natural course of vertigo control in Menière's disease, whereas both the RVN and CVN significantly improve the patient's chance of being permanently free of vertigo attacks.

Repeatability of high-frequency bone conduction thresholds.

The purpose of this study was to determine the repeatability of high-frequency, bone conduction thresholds and to increase the data base concerning high-frequency, bone conduction threshold levels. Bone conduction thresholds were obtained on 30 subjects having normal, low, and mid frequency (0.25 to 8 kHz) hearing thresholds within and across five test sessions using a Pracitronic KH 70 bone vibrator referenced to a Brüel and Kjaer 4930 mechanical coupler at 1, 4, 8, 10, 12, 14, and 16 kHz. Within and across sessions, the bone conduction thresholds were not significantly (p greater than 0.05) different at each frequency indicating that repeated testing without replacing the bone vibrator (within session) and with replacing the bone vibrator (across session) did not influence the threshold measurements. Clinical implications concerning high-frequency, bone conduction audiometry are discussed.

Acoustic radiation produced by B-71, B-72, and KH 70 bone vibrators.

The amount of acoustic radiation produced by two samples of a Radioear B-71, B-72, and Pracitronic KH 70 bone vibrator was determined for 30 normal-hearing subjects at 4000 Hz. The mean amount of acoustic radiation was very similar for both samples of each vibrator type but significantly (p less than 0.05) different between the bone vibrator types. The mean amount of acoustic radiation averaged over both samples was 8.3 dB for the B-72, 4.3 dB for the B-71, and -0.3 dB for the KH 70. Individual subject data indicated that the B-72 produced excessive acoustic radiation (greater than 5 dB) for 80% of the subjects, the B-71 for 38% of the subjects, and the KH 70 for 8% of the subjects which could cause an invalid high-frequency air-bone gap. Precautions should be taken during bone conduction audiometry to eliminate the possibility of acoustic radiation produced by bone vibrators. A need for additional standards in this area is stressed.