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PubMedDate not supplied

Conductive hearing loss evaluated by brief tone audiometry.

Bone-conduction measurements are inaccurate and often troubled by masking problems. Determination of the temporal integration of acoustic energy by Brief Tone Audiometry permits an estimate of the cochlear threshold. In 71 patients with middle ear pathology, the conductive impairment was measured using both conventional audiometry and Brief Tone Audiometry. In 85% of the patients, the estimates coincided within 15 dB. Results from pre- and post-operative measurements are given, and it is demonstrated that Brief Tone Audiometry can be used as an alternative to bone-conduction audiometry to determine the degree of conductive loss with the same accuracy, but without the latter's limitations.

Audiometry↗
PubMed1994

Mixed hearing loss in otosclerosis: indication for long-term follow-up.

This retrospective study of 146 ears with long-term follow-up after otosclerosis surgery evaluated the stability of hearing results, the incidence of sensorineural hearing loss, and the effect of fluoride treatment. Follow-up was at least 15 years (mean, 25.2 yr; range, 15-44 yr). There were 97 large fenestra stapedectomy operations, 23 lateral canal fenestrations, 7 mobilizations, and 19 revision stapes operations. The level of air-bone gap achieved at surgery remained stable over time; the mean deterioration rate was only 0.2 dB per year. Profound sensorineural hearing loss ( > or = 65 dB bone conduction average) at the most recent follow-up occurred in 13 ears (8.9%). Such hearing loss occurred in all operative groups. Mean bone conduction average immediately postoperatively was significantly higher in these ears than in others in the study. This finding indicates that a mixed hearing loss at surgery is a factor that increases the risk of later profound cochlear loss. Only 3 percent of ears with pure conductive hearing loss, but 28 percent of patients with mixed hearing loss at surgery eventually suffered profound cochlear loss. Sodium fluoride was used to treat 11 ears with progressive cochlear loss. The rate of bone conduction hearing deterioration decreased in all ears after treatment, and none developed profound hearing loss. Follow-up after the first postoperative year is not necessary if pure conductive hearing loss is present at surgery. Annual follow-up with audiograms is recommended if a mixed hearing loss is present. Fluoride treatment is recommended if inner ear hearing loss progresses.

Adult↗
PubMed2006

Canal atresia: "surgery or implantable hearing devices? The expert's question is revisited".

OBJECTIVES: (1) Evaluate hearing results in patients managed with external auditory canal reconstruction; (2) compare results to the expectations from treatment with surgical; placement of an osteo-integrated bone-conduction device (BAHA system); (3) assess complications of both interventions; (4) evaluate the medical cost-effectiveness of each avenue of management at 2005 rates for billings based upon relative value units (RVUs). METHODS: (1) Retrospective chart review for 36 ears in 29 pediatric patients who underwent surgical canal reconstruction at a tertiary-care pediatric hospital in a major urban center with assessment of management techniques and surgical and audiologic outcomes. (2) Retrospective chart review of six pediatric patients who underwent BAHA placement in a major urban center with assessment of management techniques and surgical and audiologic outcomes. (3) Cost reassessment at 2005 billings rates based upon RVUs for canal reconstruction versus BAHA system and comparative analysis. RESULTS: (1) The average post-operative hearing loss in the right ear was 34.3 dB left ear was 31.6 dB. The average gain per ear was 17.3 dB. (2) Twenty-seven (93%) of EAC reconstruction patients required some form of amplification post-operatively. (3) Data available for three of the BAHA patients reflected the predicted average gain in dB (predicted 34.3 dB, observed 31.8 dB). (4) Early complications of canal reconstruction included removal of the packing by the patient, post-operative bleeding and post-operative hematoma. (5) Late complications included recurrent canal stenosis, recurrent otitis externa, canal prolapse and canal cholesteatoma. (6) Uncomplicated external auditory canal reconstruction cost $51,505.98 or $2909.94/dB of hearing gain based upon billings fro RVUs. (7) Uncomplicated two-staged BAHA system placement cost $42,448.85 or $1237.57/dB of hearing gain based upon billings for RVUs. (8) Uncomplicated single-staged BAHA system placement cost $28,341.00 or $826.27/dB of hearing gain based upon billings for RVUs. CONCLUSIONS: Study results indicate that even with significant investments in EAC reconstruction, most patients still required some form of amplification. There are also significant risks of early and late complications from the reconstructive procedure. Studies indicate and our results support that the osteo-integrated bone-conduction device (BAHA system) can achieve truly acceptable hearing (<or=15 dB) in school-aged children with normal bone curves, and it can match the bone-curves for children with sensorineural hearing loss. The two-staged BAHA system placement may be provided at almost one-third the cost to the medical system, on a decibel-for-decibel basis. The single-stage BAHA system placement yields even greater cost savings at just over one-quarter of the cost of surgical EAC reconstruction on a decibel-for-decibel basis. Additionally, there are fewer complications and fewer follow-up visits for the care of the implant system. This is an added value to the parents and patient for the savings in opportunity costs related to the lost time at work and school for office visits and peri-operative care. Overall, it appears that osteo-integrated bone-conduction devices may provide a higher quality of outcome for patients while resulting in significant economic savings.

Bone Conduction↗
PubMed1990

Emergence of the brain-stem auditory evoked potential in the premature lamb.

Brain-stem auditory evoked potentials (BAEPs) were elicited by bone conducted stimuli in the very immature lamb following delivery, wherein liquid ventilation techniques were utilized to control cardiopulmonary and acid-base conditions, independent of umbilical-placenta support. Unlike previous studies of the in utero fetal lamb in which the BAEP could not be elicited by earphone delivered stimuli until 117 days gestation, our results demonstrate that the BAEP emerges at least as early as 106 days gestation in the lamb and consists of a full complement of readily discernible and reproducible wave forms. In addition, the results demonstrate substantial maturation of the BAEP from 106 to 122 days gestation during which time there is a significant decrease in absolute and interpeak latencies with an increase in developmental age. It is concluded that the ability to elicit the BAEP utilizing bone conduction at this early stage of gestation is related to improved stimuli delivery. Furthermore, this study demonstrates the feasibility and flexibility afforded by liquid ventilation and bone conduction BAEP techniques to study brain-stem function at particularly vulnerable stages of development.

Animals↗
PubMed1987

Mixed conductive and sensorineural hearing loss in LP/J mice.

Air and bone conduction thresholds for the detection of a compound action potential response were measured in mice of the LP/J inbred strain, which has been proposed as a possible model for human otosclerosis. Thresholds were compared with control data from CBA/Ca mice. Evidence of a mixed sensorineural and conductive hearing loss was obtained in LP/J mice. Few signs of hair cell degeneration or middle-ear bony lesions were found in 20-day old mice, although they generally showed raised thresholds to both air and bone conducted stimuli. The reason for the observed sensorineural component of the hearing loss at this age is not clear, since endocochlear potentials were normal in mice of this strain. By 225 days of age, hair cell loss was extensive and there was clearly excess bone growth in all middle-ear specimens studied, particularly on the incus and the cochlear wall facing the middle ear. Microbiological analysis of LP/J specimens revealed no evidence of a middle-ear infection specific to these mice which might explain the pathology.

Action Potentials↗
PubMed2002

Promontory drilling in stapedectomy.

OBJECTIVE: Evaluate in stapedectomy the clinical outcome and audiometric results (particularly bone conduction) of drilling the promontory because of a narrow oval window niche. STUDY DESIGN: Retrospective. SETTING: Tertiary referral center, private otology practice. PATIENTS: Twenty-five stapedectomy patients requiring promontory drilling who had surgery between 1995 and 2000. METHOD: A total of 25 patients were evaluated with a minimum 6-month follow-up. Only patients who required promontory drilling and who had complete preoperative and postoperative audiometric testing including bone conduction were included. Promontory drilling was performed with a skeeter drill to thin the promontory. Twenty-five stapedectomy patients who did not undergo promontory drilling were randomly selected from this same period as a comparison group. RESULTS: In addition to the narrow oval window niche, associated anatomical findings were facial nerve overhang in five patients and an obliterated footplate in three patients. Ninety-six percent of cases were successful (<10 dB postoperative air-bone gap). The one unsuccessful case was a strut over the mobile footplate that was later successfully revised. No patients suffered from intraoperative or postoperative tinnitus or vertigo. The mean 4-frequency (500-4,000 Hz) pure-tone average revealed slight improvement in bone conduction postoperatively. CONCLUSION: Drilling of the promontory in stapedectomy is required in only a small percentage of cases. Although audiometric results indicated the possibility of a slight amount of acoustic trauma from the drilling, the effect on hearing was minimal and not considered a contraindication to this procedure.

Adult↗
PubMed1998

Short- and long-term results of stapedectomy in children.

Studies have indicated that stapedectomy can be an effective procedure in children for correcting conductive hearing losses due to juvenile otosclerosis. However, because childhood otosclerosis is rare and children commonly choose to use hearing aids in lieu of undergoing surgery, little outcome data are available. The purpose of this retrospective study was to provide additional outcome data in both the short and the long term. Stapedectomies were performed on 47 children. Preoperative hearing results were compared with 6-month postoperative hearing results. Hearing results for the children who had long-term follow-up (5 years or more) were compared with the 6-month postoperative results. Stapedectomy was successful (postoperative air conduction pure-tone average [PTA] within 10 dB of the preoperative bone conduction PTA) in 91.7% of the cases. The mean overclosure of the preoperative bone conduction PTA by the postoperative air conduction PTA was 0.2 dB. The mean PTA hearing improvement was 32.8 dB. Results from the 21 children (28 ears) who had long-term follow-up indicated an average 0.7 dB/year PTA worsening from the 6-month postoperative PTA. Results from this study provide additional evidence that stapedectomy can be an effective procedure for correcting conductive hearing losses due to juvenile otosclerosis.

Adolescent↗
PubMed2005

Time-intensity trading in bilateral congenital aural atresia patients.

In an effort to examine the rules by which information of bilaterally applied bone-conducted signals arising from interaural time differences (ITD) and interaural intensity differences (IID) is combined, data were measured for continuous 500 Hz narrow band noise at 65-70 dB HL in 11 patients with bilateral congenital aural atresia. Time-intensity trading functions were obtained by shifting the sound image towards one side using ITD, and shifting back to a centered sound image by varying the IID in the same ear (auditory midline task). ITD values were varied from -600 to +600 micros at 200 micros steps, where negative values indicate delays to the right ear. The results indicate that time-intensity trading is present in patients with bilateral aural atresia. The gross response properties of time-intensity trading in response to bone-conducted signals were comparable in patients with bilateral aural atresia and normal-hearing subjects, though there was a larger inter-subject variability and higher discrimination thresholds across IIDs in the atresia group. These results suggest that the mature auditory brainstem has a potential to employ binaural cues later in life, although to a restricted degree. A binaural fitting of a bone-conducted hearing aid might optimize binaural hearing and improve sound lateralization, and we recommend now systematically bilateral fitting in aural atresia patients.

Acoustic Stimulation↗
PubMed2004

Aged mice require full transcription factor, Runx2/Cbfa1, gene dosage for cancellous bone regeneration after bone marrow ablation.

UNLABELLED: Runx2 is prerequisite for the osteoblastic differentiation in vivo. To elucidate Runx2 gene functions in adult bone metabolism, we conducted bone marrow ablation in Runx2 heterozygous knockout mice and found that aged (but not young) adult Runx2 heterozygous knockout mice have reduced new bone formation capacity after bone marrow ablation. We also found that bone marrow cells from aged Runx2 heterozygous knockout mice have reduced ALP(+) colony-forming potential in vitro. This indicates that full Runx2 dosage is needed for the maintenance of osteoblastic activity in adult mice. INTRODUCTION: Null mutation of the Runx2 gene results in total loss of osteoblast differentiation, and heterozygous Runx2 deficiency causes cleidocranial dysplasia in humans and mice. However, Runx2 gene functions in adult bone metabolism are not known. We therefore examined the effects of Runx2 gene function in adult mice with heterozygous loss of the Runx2 gene. MATERIALS AND METHODS: Bone marrow ablation was conducted in young adult (2.5 +/- 0.5 months old) or aged adult (7.5 +/- 0.5 months old) Runx2 heterozygous knockout mice and wildtype (WT) littermates. Cancellous bone regeneration was evaluated by 2D microCT. RESULTS: Although new bone formation was observed after bone marrow ablation in the operated bone marrow cavity of WT mice, such bone formation was significantly reduced in Runx2 heterozygous knockout mice. Interestingly, this effect was observed specifically in aged but not young adult mice. Runx2 heterozygous deficiency in aged mice significantly reduced the number of alkaline phosphatase (ALP)(+) cell colonies in the bone marrow cell cultures, indicating a reduction in the numbers of osteoprogenitor cells. Such effects of heterozygous Runx2 deficiency on osteoblasts in vitro was specific to the cells from aged adult mice, and it was not observed in the cultures of marrow cells from young adult mice. CONCLUSION: These results indicate that full gene dosage of Runx2 is required for cancellous bone formation after bone marrow ablation in adult mice.

Aging↗
PubMed1983

The effect of stapedectomy on hearing of patients with otosclerosis and Meniere's disease.

To determine new guidelines for stapedectomy in patients with both Meniere's disease and otosclerosis, we studied the position of the saccular membrane and Reissner's membrane in relation to the stapes footplate in eight temporal bones from patients with Meniere's disease. We also reviewed charts of four patients with both otosclerosis and Meniere's disease who had stapedectomy. Histologic and clinical findings were compared with preoperative bone conduction levels at 500 Hz and at high frequencies. We found that the saccular and Reissner's membranes did not contact the stapes footplate ain bones of patients with preoperative bone conduction levels of 35 dB or better at 500 Hz and no high-frequency loss. We also found that stapedectomy was successful in patients with the same criteria. We therefore conclude that stapedectomy does not increase the risk of sensorineural hearing loss for patients with otosclerosis and Meniere's disease who have bone conduction levels of 35 dB o better at 500 Hz and no high-tone loss, but it is contraindicated for patients with 45 dB at 500 Hz or worse and with high-tone loss.

Hearing Loss, Sensorineural↗
PubMed2001

Recent outcome of tympanoplasty in the elderly.

OBJECTIVE: To investigate the outcome of tympanoplasty in the elderly (patients older than 60 years) compared with younger patients. PATIENTS AND STUDY DESIGN: Retrospective review of 87 (28.3%) older patients among a total of 307 patients with chronic otitis media with or without cholesteatoma who were surgically treated at a university hospital by the senior author. Follow-up was systematically provided at the same institution. INTERVENTIONS: Surgery included tympanoplasty with mastoidectomy performed as the primary procedure in 358 ears. Tympanoplasty was performed with canal-wall-up or canal-wall-down with canal wall reconstruction, ossiculoplasty with autologous or homologous ossicle interposition or columella. Mean follow-up was 30 months (range, 12-70 months). MAIN OUTCOME MEASURES: Pre- and postoperative air- and bone-conduction thresholds were calculated as an average of three speech frequencies (0.5, 1, and 2 kHz). Analysis was subsequently carried out on the postoperative air-bone gap, hearing gain, and postoperative problems such as elevation of the bone-conduction threshold, delayed epithelialization, and reperforation of the eardrum. Statistical analysis was performed by chi-square or Student's t-test. A p value less than 0.05 was considered significant. RESULTS: Compared with results from younger patients, there was no particular disadvantage in postoperative hearing results and complications in the elderly, although preoperative bone-conduction thresholds were gradually worsened with age. CONCLUSIONS: There is no contraindication for tympanoplasty in older patients if their physical status is the same or better than what is normal for their chronological age.

Adolescent↗
PubMedDate not supplied

Influence of temperature on the output of a mechanical coupler.

This research determined the influence of temperature on the output of two Bruel and Kjaer 4930 mechanical couplers using a Radioear B-71, B-72, and a Pracitronic KH 70 bone vibrator. When the temperature of the mechanical couplers was varied from 17 degrees C (62.6 degrees F) to 29 degrees C (84.2 degrees F) in steps of 3 degrees C (5.4 degrees F) and the bone vibrators had a constant temperature, the output of each mechanical coupler systematically decreased as its temperature increased for each bone vibrator type. The largest output differences for both couplers and each vibrator occurred at 4000 Hz. The average of these differences across the couplers and vibrators was 6.6 dB higher at 17 degrees C than at 29 degrees C which dB/3.6 degrees F). When the temperature of the bone vibrators was 17 and 29 degrees C and the mechanical couplers were maintained at a constant temperature, there were little or no differences in the output of the mechanical couplers. The temperature of a mechanical coupler rather than that of the bone vibrator is a critical variable in bone conduction calibration. Mechanical coupler temperature-dependent output coefficients were determined for use in bone conduction calibration from 250 to 4000 Hz for all three bone vibrator types and at 6000 and 8000 Hz for the KH 70.

Audiometry↗
PubMed1995

Chronic otitis media and sensorineural hearing loss: is there a clinically significant relation?

Previous investigations into the possible relation between chronic otitis media (COM) and sensorineural hearing loss (SNHL) have resulted in differing results and conclusions. A retrospective study was conducted to examine the relation between COM and SNHL, using strict selection criteria for cases so as to eliminate co-variables. In addition, various COM parameters were studied to determine if a correlation with the severity of the SNHL existed. At the University of Virginia, charts of all patients undergoing chronic ear surgery from September 1983 to March 1993 were reviewed. Sixty-nine patients met the following criteria: unilateral COM and no history of head trauma, meningitis, post-traumatic tympanic membrane perforation, labyrinthine fistula, or coexisting otologic condition of either ear. From these charts, audiograms were then analyzed for evidence of SNHL, defined as the difference in preoperative bone conduction thresholds between diseased and control (normal contralateral) ears. Mean bone conduction differences were small: -0.5 dB at 500 Hz, 0.9 dB at 1,000 Hz, 4.4 dB at 2,000 Hz, and 3.6 dB at 4,000 Hz. There were nonsignificant bone conduction threshold differences that trended toward greater SNHL with diseased mucosa and cholesteatoma at 2,000 and 4,000 Hz. There was no consistent correlation between severity of SNHL and presence of otorrhea, degree of ossicular erosion, or duration of disease. The authors conclude that COM may cause SNHL, but in the vast majority of patients this loss is not clinically significant.

Adolescent↗
PubMed1997

Hearing results in otosclerosis surgery after partial stapedectomy, total stapedectomy and stapedotomy.

Hearing results in a consecutive series of 407 patients with otosclerosis undergoing primary stapes surgery were analysed (437 operated ears). Partial stapedectomy was performed in 70 ears (16%), total stapedectomy in 205 ears (47%), in both groups using the House steel wire prosthesis on fascia in the oval window. The remaining 162 ears (37%) underwent stapedotomy using the Fisch 0.4 mm teflon-platinum piston. No case of cochlear loss (> 15 dB) occurred in the total series. The comparison between the three groups one year postoperatively showed that the air-bone gap was smaller for partial and total stapedectomy for all frequencies except 4 kHz. The air-bone gap was calculated as the difference between the preoperative bone conduction and the postoperative air conduction thresholds. Partial and total stapedectomy also showed larger improvements of bone conduction thresholds compared with stapedotomy for all frequencies but 4 kHz. At the 3-year follow-up, the hearing gain for all frequencies (250-8000 Hz) was larger for partial and total stapedectomy. Yet, when comparing the decline of hearing from 1 to 3 year postoperatively, the hearing gain achieved with partial and total stapedectomy seemed to deteriorate at a higher rate, which was considered to be caused by impaired sensorineural function. Our results show that in the short-term perspective partial or total stapedectomy can still compete for better hearing results even at higher frequencies, but stapedotomy seems to yield more stable hearing results over time and should therefore be considered as the method of choice.

Adolescent↗
PubMed1997

Auditory brainstem responses after radiotherapy for nasopharyngeal carcinoma.

The effect of irradiation for nasopharyngeal carcinoma on auditory brainstem responses and hearing was investigated in 19 otologically normal patients undergoing standard fractionated megavoltage radiotherapy. Auditory brainstem responses and pure tone audiometry were performed before radiotherapy, and at 3 and 12 months after completion of radiotherapy. There were no significant changes in the wave I-III and III-V interpeak intervals, or in sensorineural hearing thresholds (bone conduction at 4 kHz and average of bone conduction at 0.5, 1, 2 and 4 kHz), after radiotherapy. In contrast to previous studies, we found no evoked potential evidence of subclinical brainstem damage arising from irradiation for nasopharyngeal carcinoma.

Adult↗
PubMed2005

Argon laser assisted small fenestra stapedotomy for otosclerosis.

To report and analyse our results and complications of argon laser assisted stapedotomy for primary otosclerosis. A retrospective analysis of 135 consecutive cases of primary otosclerosis operated by the senior author (JH) has been performed. The air-bone gap was calculated by using the pure tone average at 500, 1000, 2000 and 4000 Hz. A separate analysis of air-bone gap at 500, 1000 and 2000 Hz was carried out to assess the effects of a small diameter piston on low frequency hearing. Hearing at high frequencies (4000 and 8000 Hz) was also assessed to evaluate effects of small fenestra technique on high frequency hearing. Preservation of cochlear function was assessed by comparing the average pre- and post-operative bone conduction thresholds. Complications arising were analysed. The post-operative air-bone gap at 0.5, 1 and 2 kHz was 10 dB or less in 85.19% of patients and 20 dB or less in 97.04% patients. The air-bone gap at 0.5-4 kHz was <or=10 dB in 77.04% of patients and 20 dB or less in 97.04% patients. The majority of patients showed an improvement at 4 kHz (81.4%) and 8 kHz (60.7%). There was no change in the average pre- and post-operative bone conduction thresholds. There were no major complications. Argon laser reduces mechanical trauma to the vestibule and increases precision resulting in consistent hearing results in all frequencies and reduced post-operative morbidity.

Adult↗
PubMed2001

Hearing results after tympanoplasty in elderly patients with middle ear cholesteatoma.

Many reports about the effect of aging on hearing results after tympanoplasty have been published. However, they have not been evaluated comprehensively, i.e. by taking into consideration other aspects which also affect the outcome. In this study, the effect of aging on hearing results after canal wall reconstruction tympanoplasty was assessed in 236 consecutive ears of 213 patients > 20 years old with middle ear cholesteatoma. The elderly group (n = 34), defined as patients > or = 60 years old, was compared to the younger groups in terms of hearing results of postoperative hearing level, hearing gain, A-B gap and change in bone conduction hearing level at 4000 Hz after adjustment for age, gender, staged operation, preoperative hearing level and type of tympanoplasty, all of which affect hearing results, using the generalized linear regression method. Postoperative hearing level and hearing gain were found to be better amongst patients aged 20-29 and 30-39 years than in the elderly group, whilst A-B gap did not differ between all age categories. Within the elderly group, air conduction hearing level was shown to have improved after surgery. Changes in bone conduction hearing level at 4000 Hz were not significantly different between the age groups, suggesting that operative stress, i.e. mechanical stress or ossicular manipulation stress, does not aggravate sensorineural hearing loss in the elderly. We conclude that surgeons should be encouraged to perform tympanoplasty aimed not only at eradicating the lesion itself but also at improving hearing acuity in the elderly.

Adult↗
PubMed2000

Percutaneous bone-anchored hearing aids at a pediatric institution.

OBJECTIVES: The goals were to evaluate hearing, complications, and patient satisfaction with the percutaneous bone-anchored hearing aid (BAHA) and to monitor long-term successful use achieved by careful patient selection. METHODS: This prospective longitudinal study included participants with inoperable congenital bilateral aural atresia, pure-tone average (PTA) bone conduction less than 45 dB HL, prior use of a conventional bone-conduction hearing aid (CBCA), and adequate intelligence, integration, and personal hygiene. Surgery for BAHA implantation was performed in two stages. Evaluation consisted of skin reactions, audiologic results with CBCA and BAHA, and patient satisfaction. Follow-up was at least 24 months. RESULTS: In 11 participants aged 5 to 17 years, the PTA free-field air conduction improved 37%, and free-field speech discrimination improved 23%. Successful integration and implant use were achieved in 10 cases but were lost in 1 case as a result of head trauma. All patients preferred the BAHA as opposed to the CBCA. CONCLUSIONS: The BAHA is a valuable device that can improve hearing and provide significant parent and patient satisfaction. Careful selection appears to correlate with successful long-term use.

Adolescent↗