Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Bone Conduction”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 613 records · Page 34Linked to original sources

Hearing loss in patients with enlarged vestibular aqueduct: air-bone gap and audiological Bing test.

The Bing test is based on the principle that occlusion of the external auditory meatus improves the perception of bone-conducted sounds unless there is a conductive hearing impairment. An air-bone gap has been reported in patients with large vestibular aqueduct (LVA) syndrome without apparent middle ear dysfunction. We therefore performed the Bing test on nine patients with this syndrome to evaluate whether it is associated with an air-bone gap or middle ear dysfunction. Bone conduction thresholds did not change significantly during the Bing test in any patient. Because an air-bone gap is observed in patients with abnormal communication between the inner ear and cerebrospinal fluid through the LVA, dehiscent superior canal, or dilated inner ear meatus; we propose that a 'three windows' model (in which the abnormal communication provided by the enlarged endolymphatic duct and sac in LVA acts as the 'third window' for sound conductance) might explain the air-bone gap in such patients.

Adolescent↗

Topical ciprofloxacin for otorrhea after tympanostomy tube placement.

OBJECTIVE: To evaluate the efficacy, systemic absorption, and safety of ototopically administered ciprofloxacin in children with otorrhea associated with tympanostomy tube placement. DESIGN: Nonrandomized, open-label pilot trial with pharmacokinetic determination of the systemic absorption of ototopical ciprofloxacin. SETTING: A pediatric otolaryngology clinic affiliated with Columbus (Ohio) Children's Hospital. PATIENTS: Patients aged 3 to 8 years were enrolled if they had persistent otorrhea associated with tympanostomy tube placement. Other inclusion criteria were culture of Pseudomonas aeruginosa from the drainage material; failure of previous oral antibiotic therapy; and ability to participate in bone conduction audiometry. INTERVENTION: Participants received 3 drops (approximately 60 microL) of 0.3% ototopical ciprofloxacin hydrochloride (Ciloxan, Alcon Laboratories Inc, Forth Worth, Tex), three times a day, for 14 days. Bone conduction audiometry was performed at baseline and on day 14. Patients were examined on days 7 and 14 for efficacy of treatment (improvement, cure, failure) and adverse effects. On day 7, blood samples were drawn just before and 1 hour after the dose was given. Concentrations of ciprofloxacin were measured by high-performance liquid chromatography, with a 5 ng/mL limit of detection. Telephone follow-up was performed on day 44. Parents were asked about adverse effects at days 7, 14, and 44. RESULTS: Mean duration of ear drainage at baseline was 10.7 months (0.75 to 36 months). Ten of 11 infected ears (nine of 10 patients) were improved or cured at day 7. Ten of 11 ears were completely cured at days 14 and 44. No adverse effects were noted or reported by the children's parents. One child had abnormal bone conduction audiometry results at baseline. The results of bone conduction audiometry on day 14 were normal in all children. Trough concentrations of ciprofloxacin were determined in eight of 10 children; and peak concentrations were determined in seven of 10 children. Ciprofloxacin was not detected in the plasma of any child. CONCLUSION: Topical ciprofloxacin was found to be safe and effective in treating otorrhea in children who did not respond to other treatments.

Administration, Topical↗

Ambient noise levels in nursing homes: implications for audiometric assessment.

Conducting hearing tests and hearing screenings in the nursing home environment can be a challenge. One issue which may affect the validity of the test results is the level of ambient noise in those facilities when a sound-treated booth is not available. This study sampled the ambient noise levels in ten different nursing homes and compared those results to the ANSI S3.1--1999 criteria for maximum permissible ambient noise levels. Based on the results of this investigation, the use of insert earphones for air conduction assessments is recommended when a sound-treated booth is unavailable and noise levels exceed the ANSI criteria. Other suggestions regarding air-conduction and bone-conduction assessments are discussed.

Audiometry↗

[Effect of occlusion. Part II. Theoretical and practical implications].

The theoretical and practical consequences of the experiments described in part I are discussed. They concern the following topics: 1. The stability of the occlusion effect: in contrary to the opinions expressed in the literature--the stability of the effect for a particular earphone is of range of normal deviation in threshold of hearing. 2. Bone conduction threshold shift in occlusion effect represents change in proportions of the air- and bone-components of the normal bone conduction threshold: an increase of the air component on the expense of the bone component. The shift do not represents the change in perception. In that respect the shift is a spurious phenomenon. 3. Depending on the presence or the lack of occlusion effect all the ears were divided into classes: "occlusive" and "non-occlusive". a) the occlusive ears include the ones with normal conduction (healthy or the hearing- impaired ears) covered with earphones during bone conduction tests, b) the non-occlusive are the ears mentioned under "a", but unoccluded and all the ears with conductive loss (regardless the occlusion). The audiometric norm for bone conduction threshold, established in non-occlusive state (which is the usual procedure in the conventional audiometry) are suitable only for the non-occlusive ears. And vice versa: the occlusion norm (found in a routine Rainville procedure) may be applied only for occlusive ears.

Audiometry↗

Characterization of severely and profoundly hearing impaired adults attending an audiology clinic.

Despite the fact that around 12 per cent of adult patients attending an audiology department will be severely hearing impaired (pure tone averages of 0.5, 1, 2 and 4 kHz of 70 dB HL or worse in the better hearing ear), their clinical and audiometric characteristics have not been well documented. These characteristics were collected prospectively in 132 adult patients attending a Severe Impairment Clinic, set up to manage their specific problems. The inability to provide sufficient masking makes audiometric assessment of the severity of the impairment uncertain in the poorer hearing ear in 52 per cent of these patients. In addition, the limited bone conduction output makes it almost invariably impossible to assess the masked bone conduction thresholds and hence the air-bone gap in the poorer ear. Hence, accurate characterization is only practical of the better hearing ear in such patients. In 67 per cent of the better hearing ears, there was a mixed hearing impairment, the air-bone gap being 20 dB or greater. The aetiology of the conductive component was almost equally otosclerosis and chronic otitis media. In only 19 per cent was the impairment of a pure sensorineural type, broken down as 6 per cent congenitally acquired, 5 per cent due to meningitis and 9 per cent being adult in onset. In the remaining 14 per cent of patients the type of impairment could not be classified as the bone conductive thresholds were off scale. Having had experience of managing these patients at a special clinic and knowing the workload involved, it is argued that consideration be given to setting up such clinics in most departments.

Adolescent↗

Safety of the erbium:yttrium-aluminum-garnet laser in stapes surgery in otosclerosis.

OBJECTIVE: The purpose of this study was to present early and late bone-conduction hearing thresholds and data about cochlear and vestibular disturbances in patients after erbium:yttrium-aluminum-garnet (Er:YAG) laser stapedotomy in otosclerosis. STUDY DESIGN: The study design was a retrospective study. SETTING: The study was conducted at an academic tertiary referral center. PATIENTS: In this study, audiologic data of 117 patients undergoing Er:YAG laser-assisted stapedotomy for otosclerosis between 1993 and 1999 were included. MAIN OUTCOME MEASURES: The preoperative minus 2 postoperative (early, 1-3 days; late, at least 6 weeks) average pure-tone bone-conduction thresholds at 1, 2, and 4 kHz and 0.5, 1, 2, and 3 kHz were calculated. The postoperative appearance of nystagmus, vertigo, and tinnitus was analyzed. RESULTS: A total of 91 of 117 patients showed unchanged preoperative minus postoperative pure-tone bone-conduction averages at 1, 2, and 4 kHz in the late postoperative measurement. A slight deterioration was observed in 8 of 117 patients. Regarding the frequencies 0.5, 1, 2, and 3 kHz, 97 of 117 patients showed unchanged preoperative minus postoperative pure-tone bone-conduction averages. A new transient tinnitus appeared in 37 of 117 patients, and a new persistent tinnitus was found in 3 of 117 patients. Most of the patients had no postoperative dizziness (63/117 patients) and no postoperative nystagmus (109/117 patients). CONCLUSION: The study did not show significant sensorineural hearing loss at or below 3 kHz. Vestibular and cochlear function has no clinically relevant suppression after Er:YAG laser stapedotomy.

Adolescent↗

[Bone anchored hearing aids (B.A.H.A.)].

Semi-implantable bone conduction hearing aids of the type Bone Anchored Hearing Aids (B.A.H.A.) consist of an external vibrator hearing aid that is attached to a titanium screw implanted in the mastoideal bone behind the ear by means of a transcutaneous connector. In this way sound waves are transmitted directly to the bones of the skull, from where they are conducted to the cochlea. The primary indication for a semi-implantable bone conduction hearing aid is hearing loss due to conduction failure that is not surgically correctable. This may be caused, e.g. by ear canal atresia and other malformations of the external auditory meatus and of the middle ear, by chronic ear infections or by persistent high grade conduction hearing impairment after radical mastoidectomy. Today B.A.H.A.'s largely replace the less convenient conventional bone conducting hearing aids as hearing glasses or hearing bands, in which a vibrator is pressed against the skull. In conduction hearing impairment on both ears B.A.H.A.'s can be implanted bilaterally and thus binaural hearing with sound source localisation are made possible. A novel application is in cases of unilateral deafness, where the device is implanted on the side of the deaf ear and the amplified sounds are transmitted through the skull to the side of the hearing ear. Here it serves as a substitute for a CROS hearing aid. In adults the implantation is performed under local anesthesia as an out-patient procedure. Implantation may be undertaken under general anesthesia on children after two years of age. In Berne, B.A.H.A. bone conduction hearing aids have been implanted in 112 patients (ages 2-82 years) in the past 13 years. The operations have proved simple and without intra-operative complications. The long-term post-operative incidence of complications was low. The transcutaneous screw caused only isolated cases of transient skin reactions or local infections. In 7% of cases, rejection of the implant or a traumatic loosening of the screw required a reimplantation procedure. Over 90% of patients reported themselves satisfied with their partially-implantable B.A.H.A. hearing aids.

Adolescent↗

Congenital stapes ankylosis: study of 28 cases and surgical results.

OBJECTIVE: The objective of this study was to analyze functional results after stapes surgery in patients with congenital nonprogressive conductive deafness resulting from an isolated fixation of the stapes according to age and surgical procedure. STUDY DESIGN: The authors conducted a retrospective case series from March 1993 to December 2003 in patients from two tertiary referral centers. METHODS: Twenty-eight patients were operated on by stapedotomy or partial stapedectomy using Teflon stapes prostheses. The median age at surgery was 14.2 years (range, 8.3-29.1 years). Main outcome measures were clinical and audiometric evaluation before and after surgery. Mean air conduction (MAC) and bone conduction (MBC) thresholds were recorded at 0.5, 1, 2, and 4 kHz. The evaluation of functional outcome was based on the MAC gain, the MBC comparison, and the mean postoperative and residual air-bone gaps. RESULTS: The median preoperative MAC was 50 dB (range, 19.0-65.0 dB) with a 35.0 dB median dB air-bone gap. With a mean follow up of 19 months, postoperative hearing improvement was statistically significant: median gain of 32.5 dB (P<.001) and median residual air-bone gap of 3.5 dB. The MBC was also statistically improved with median pre- and postoperative MBC of 11.5 and 6.5 dB, respectively (P<.001). Results were not dependent on the age group or type of surgery (stapedotomy or partial stapedectomy). No perceptive hearing loss was observed despite one gusher case. CONCLUSION: Surgical treatment of isolated congenital stapes ankylosis allows good functional results regardless of age or type of surgery.

Adolescent↗

Hearing in acromegaly.

Fifty-six individuals with acromegaly referred for pituitary surgery were studied to determine any relationship between acromegaly and sensorineural or conductive hearing loss. Compared to a matched population control sample, no significant difference between the acromegalics and controls has been found, either for air conduction or for bone conduction. The differences between these findings and those published previously are discussed, and reasons proposed to explain the discrepancies.

Acromegaly↗

Bone vibrator placement and the cancellation technique.

An issue in the measurement of bone conduction sensitivity is the placement of the bone vibrator. The effect of bone vibrator position on the amplitude and phase of the received signal was investigated using a cancellation technique. This technique involves cancelling the signal delivered by the bone vibrator with a signal delivered acoustically via an earphone. At cancellation, the acoustic signal is equal in amplitude but opposite in phase to the bone-conducted signal. Results showed that the amplitude of the received signal did not vary significantly with bone vibrator position close to the center of the forehead whereas the phase of the received signal was critically dependent on bone vibrator position. Substantial intersubject differences were observed in the variation of phase with bone vibrator position. The precision of measurement using the cancellation technique was found to be high.

Acoustics↗

Stapedectomy for far-advanced otosclerosis.

OBJECTIVE: This study aimed to describe far-advanced otosclerosis and to present the authors' results with stapedectomy in 78 ears with far-advanced otosclerosis. STUDY DESIGN: The study design was a retrospective case review. SETTING: The study was conducted at an Otology/Neurotology tertiary referral center. PATIENTS: Stapedectomy was performed on 78 ears of 60 patients with far-advanced otosclerosis, and the results followed from 1 to 21 years with a mean of 5 years. INTERVENTION: Stapedectomy was performed on all ears with far-advanced otosclerosis. MAIN OUTCOME MEASURE: Hearing for air conduction (AC) and bone conduction (BC), speech discrimination, and impedance were tested on all patients before and after operation. The Rinne test was performed on all ears with a 256-cycle magnesium tuning fork. The pure-tone average for AC and BC was computed for 500, 1,000, and 2,000 Hz. Hearing improvement was defined as air-bone gap closure to 10 dB or less and/or AC improvement of 20 dB or more, with no decline in speech discrimination score of more than 10%. RESULTS: Hearing improvement was achieved in 52 (66.7%) of 78 ears of all operations. In group 1, AC was greater than 90 dB, BC was greater than 60 dB, and hearing improved in 26 (81.2%) of 32 ears of operations. In group 2, AC was greater than 90 dB and no measurable BC and hearing improved in 11 (68.8%) of 16 ears of operations. In group 3, there was no measurable AC and BC greater than 60 dB and hearing improved in two (50%) of four ears of operations. In group 4, there was no measurable AC and BC and hearing improved in 11 (42.3%) of 26 ears of operations. Nonmeasurable BC became measurable in 42.9% of ears, nonmeasurable AC became measurable in 73.3% of ears, and all of these became aidable after operation. CONCLUSIONS: A negative Rinne test result with a 256-Hz magnesium tuning fork proved to be the best test to separate far-advanced otosclerosis from sensorineural hearing loss of other causes. Stapedectomy is of benefit in most ears with profound hearing loss of far-advanced otosclerosis, especially in those ears with some measurable hearing by AC.

Adolescent↗

Bone and air conduction after stapedectomy.

UNLABELLED: Otosclerosis causes loss of air conduction (AC) but also bone conduction (BC) may be deteriorated. It is reported that also BC may improve after surgical treatment of otosclerosis. The investigation was carried out in a group of 50 patients treated due to otosclerosis in our institution. The group included 34 women and 16 men, at the age 24 to 55 years. Pure-tone audiometry for bone and air conduction threshold was performed in all the patients. Hearing tests were carried out before and 2-4 months after the operation by the same technician Partial. Only patients with air-bone gap closure were included in the study. Stapedectomy was performed under local anaesthesia. RESULTS: Significant improvement of AC was obtained after stapedectomy. There was also significant improvement of BC at all the frequencies examined of 6-12 dB and it depended on BC threshold before surgery. In the group of 37 patients with BC threshold before surgery > or = 30 dB a significant improvement of BC after stapedectomy developed. In the group of 14 patients with BC threshold before surgery < 30 dB the change of BC after stapedectomy was not significant. Successful stapedectomy improves bone conduction. It means that in patients with otosclerosis there is a reversible BC pseudo hearing loss and it is related to BC threshold before the operation.

Adult↗

Stapedectomy: long-term hearing results.

The initial improvement in hearing following stapedectomy usually deteriorates with the passage of time. We studied the long-term results of stapedectomies performed on 42 patients (49 ears) between 1959 and 1969 who had a minimum follow-up of 18 years. Both air conduction (AC) and bone conduction (BC) thresholds progressively deteriorated over the long term. The degree of BC loss paralleled that expected from presbycusis alone. A greater deterioration was noted in the AC levels, producing a recurrent conductive hearing loss in the speech frequencies. Age at the time of surgery had no effect on the long-term outcome. Comparison of the average preoperative speech discrimination scores (SDS) to the 1-year postoperative SDS and the long-term SDS revealed a 1.1% and 16.7% drop, respectively. The improvement in the average speech reception threshold (SRT) obtained 1 year postoperatively deteriorated by less than 1 dB per year over the long term. Patients with a higher SDS (more than 95%) preoperatively fared better in the maintenance of speech discrimination than those with a lower SDS (less than 95%). The preoperative SRT level was predictive of the timing for the requirement of hearing amplification. The postoperative SRT level was predictive of the timing for the requirement of hearing amplification. The caused by presbycusis, combined with a recurrent conductive loss in the speech frequencies rather than cochlear otosclerosis. Although the decline in hearing following stapedectomy exceeds the rate of hearing loss due to presbycusis, many individuals, after successful stapes surgery, are able to delay the need for hearing amplification for longer periods than had been previously reported.

Audiometry, Pure-Tone↗

Some pitfalls in the evaluation of auditory function after surgical procedures.

Because clinical bone conduction is composed of at least three different mechanisms, two of which are air conduction, uncritical use of the air-bone gap in connection with surgical procedures may give rise to erroneous conclusions. Genuine bone conduction may be influenced by ear pathology and by surgery due to alterations in the mechanical impedance at the site of application of the bone vibrator and at the round and oval windows. The supplementary use of impedance audiometry and advanced speech audiometry is recommended.

Acoustic Impedance Tests↗

Early anchoring collagen fibers at the bone-tendon interface are conducted by woven bone formation: light microscope and scanning electron microscope observation using a canine model.

To clarify the early process of recovery at the bone-tendon interface, we used light microscopy and SEM to examine the process of anchoring of collagen fibers to bone in a canine model. At two weeks, tendon, scar tissue, woven bone and lamellar bone were present at the insertion site. SEM revealed anchoring of collagen fibril bundles of the scar to the woven bone. By 4 weeks, the number of anchoring fibers had increased and a parallel arrangement of fibers was observed. SEM demonstrated deep penetration of fibers into the woven bone layer. In addition, the fibers were observed to project into and intermingle with the scar tissue. By 6 weeks, the anchoring fibers had developed fully and were distributed densely over the interface. SEM also revealed that the collagen fibril bundles in the scar tissue had connected with the collagen fibrils of the woven bone by way of the anchoring bundles. The woven bone was identifiable throughout the early stages of recovery as the interface between soft tissue and hard tissue. Throughout all experimental periods, no staining was observed at the interface of the tendon and bone by Saffranin-O. The formation of woven bone was important during early recovery of the tendon-bone interface prior to the completion of fibrocartilage-mediated insertion.

Animals↗