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At least 973 records · Page 54Linked to original sources
PubMed1999

Myringoplasty in children: predictive factors of outcome.

OBJECTIVES: To assess the results of myringoplasty in children and to determine which factors independently influence the postoperative results. STUDY DESIGN: Retrospective study of the anatomic and functional results of 231 consecutive myringoplasties performed in 188 children between 1988 and 1992. Multivariate analysis of poor prognostic factors by cross-sectional comparison 1 year after surgery. METHODS: Myringoplasties were performed via an endaural approach with a fascia temporalis underlay graft. RESULTS: In 216 of 231 ears (93.5%) the tympanic membrane was closed. A good anatomic outcome was considered to have been achieved in 188 ears (81.6%), although in 18 ears (7.8%) seromucous otitis media occurred, in 8 ears (3.5%) a progressive retraction pocket was encountered, and in 2 ears significant lateralization was present. One hundred thirty-nine (67.5%) of the 206 ears tested in the postoperative period had a postoperative air-bone gap of 10 dB or less. On average, mean bone conduction remained unaltered. The age of the patient and the size and the location of the perforation did not affect the outcome. Three prognostic factors for an abnormal postoperative tympanic membrane were found, with 95% confidence intervals: inflammatory changes in the middle ear mucosa (P < .05), contralateral tympanic perforation (P < .05), and contralateral cholesteatoma (P < .01). CONCLUSIONS: Myringoplasty with underlay grafting of the fascia temporalis in children gives good anatomic and functional results. Inflammatory changes within the middle ear mucosa, contralateral tympanic perforation, and contralateral cholesteatoma independently influence the risk of an abnormal postoperative tympanic membrane. The presence of one of these factors preoperatively should lead to the consideration of alternative, more durable graft material, such as autologous cartilage.

Adolescent↗
PubMed2005

Tinnitus improvement with ultra-high-frequency vibration therapy.

This study reports on the long-term benefit of ultra-high-frequency masking with the UltraQuiet device. A commercial product, UltraQuiet provides a new form of high-frequency bone conduction therapy. To assess its effectiveness in tinnitus treatment, we selected 15 patients with problematic tinnitus and randomly assigned them to three variations of the medical-audiological tinnitus patient protocol modified for the UltraQuiet study. We assessed tinnitus relief by questionnaires directed at weighing patient response to overall effectiveness, tinnitus loudness, tinnitus severity, and tinnitus annoyance. Additionally, we performed audiological measures (including pure-tone and speech audiometry, minimal masking levels, pitch and loudness matching, and residual inhibition). All patients showed some long-term gains, and most exhibited relief in at least one measurement parameter, providing support for the use of high-frequency vibration in the treatment of tinnitus.

Acoustic Stimulation↗
PubMedDate not supplied

[Effect of caloric stimulation of the vestibular apparatus on hearing function].

Changes of bone-conduction thresholds for tonal signals (250 and 2000 Hz) in each car due to caloric vestibular tests were studied in 60 healthy test subjects (32 men and 28 women). These changes were found in 48 subjects. In most cases perceptual thresholds decreased (by 7.3 dB on the average) and in few cases increased (by 8.3 dB on the average). The sign of alteration was independent of the tonal vestibular test or the number of examinations. The threshold returned to the norm for a long time (30 min or more). These findings suggest that the interaction may be governed by the principles that function in other sensory systems. It is recommended to carry out audiological examinations prior to vestibular tests in order to avoid distortions of the results.

Adolescent↗
PubMed2005

Vestibular evoked myogenic potentials induced by intraoperative electrical stimulation of the human inferior vestibular nerve.

Vestibular evoked myogenic potentials (VEMPs) can be recorded from sternocleidomastoid muscle (SCM) in clinical practice. The aim of the present study was to investigate VEMPs upon direct electrical stimulation of the human inferior vestibular nerve to evidence the vestibulocollic reflex arch and their saccular origin, respectively. Seven subjects were stimulated at the inferior (IVN) and superior (SVN) vestibular nerve. The EMG signals of the SCM were recorded. These recordings were compared to air- and bone-conduction evoked VEMPs with respect to latency and shape. All subjects showed normal VEMPs upon acoustic stimulation with a latency of 12.8+/-1.4 ms for P13, and 22.7+/-2.0 ms for the N23 pre-operatively. Upon direct electrical stimulation of the IVN, the mean latency of the positive peak was 9.1+/-2.2 and 13.2+/-2.3 ms for the negative one. No contralateral SCM response was found. Electrical stimulation of the SVN did not result in any EMG response of the SCM. The study shows experimental evidence of the vestibulocollic reflex by direct electrical stimulation of the human IVN for the first time. The method can be utilized to map VIIIth nerve subdivisions and to intraoperatively monitor IVN integrity in a real-time mode.

Acoustic Stimulation↗
PubMed1988

Skin tolerance and adaptation following implantation of the Xomed Audiant bone conductor.

Placement of the Xomed Audiant implantable bone conduction hearing prosthesis was initially restricted to a limited number of investigators. It was introduced to other otolaryngologists in a workshop on August 15-16, 1986. There have since been several workshops offered by Xomed and Dr. Hough, who developed the device, to train otolaryngologists how to implant this device. The literature thus far is limited to the experience of Hough and others involved with his initial trials. He has not reported any significant complications associated with this device. The purpose of this paper is to communicate a complication resulting from the use of this device. Skin ulceration over the implant resulted from excessive use of the hearing prosthesis within 2 weeks of the initial fitting. Other contributing factors in the breakdown of skin will be discussed along with suggestions regarding prevention.

Aged↗
PubMedDate not supplied

Estimation of the pure-tone audiogram by the auditory brainstem response: a review.

This review paper briefly considers how stimulus, noise masking and recording parameters affect the frequency and place specificity of auditory brainstem responses (ABRs) to air- and bone-conducted stimuli. Issues concerning the use of clicks for ABR threshold estimates will first be presented, followed by results for tone-evoked ABR thresholds and how well they predict the pure-tone behavioral audiogram. Noise-masking options (e.g. high-pass noise, notched noise and white noise) to improve the frequency specificity of tone-evoked ABRs, which are now available on clinical ABR units, will also be discussed. The goal of this article is to demonstrate that ABRs to tonal stimuli can be successfully recorded in most clinical environments and can provide reasonably accurate estimates of 500- to 4000-Hz pure-tone behavioral thresholds in infants, children and adults. Specific parameters and protocols for obtaining frequency-specific ABR threshold responses are provided.

Adult↗
PubMedDate not supplied

Effects of X-ray irradiation on hearing in guinea pigs.

Effects of X-ray irradiation on the hearing with CM and ABR to both air- and bone-conduction stimuli were studied continuously from immediately after the irradiation to a few weeks later. At 2, 4, and 6 krad, only slight conductive hearing impairment was found, but at 8 krad or more, CM and ABR disappeared abruptly, after having increased briefly. Advanced sensorineural hearing loss appeared at about 10 hours after irradiation ended at 8 krad, at about 6 hours at 10 krad, and at about 3 hours at 12 krad. More severe hearing impairment was observed at higher frequencies and the endocochlear d.c. potential (EP) decreased at about 7 hours after 10 krad irradiation. Histologically, no discernible changes in the hair cells or sensory hairs were found with a scanning electron microscope at about 6 hours after 10 krad irradiation, while with a transmission electron microscope, the outer hair cells in the basal coil of the cochlea were found to be mostly destroyed. However, no changes could be found in the inner hair cells or other supporting cells.

Animals↗
PubMed1994

Improvement in sensorineural auditory threshold of the guinea-pig fetus following delivery.

The human fetus in utero is hypoxic relative to the neonate due to differences between placental and pulmonary oxygenation. Comparable degrees of hypoxia induced in young and adult animals caused an elevation in hearing threshold of a sensorineural nature. It was hypothesised therefore that the human fetus may also have such an elevation of threshold. This was tested in this study by recording ABR thresholds to bone conducted stimuli in fetal guinea-pigs that were near full term and again in the same animals, after delivery and consequent pulmonary oxygenation. In every animal studied (n = 9), the neonatal threshold was better than that in the fetus. In those fetuses in which a response could be recorded (n = 5), the neonatal threshold was on average 20 dB better than in the fetus. These findings are probably due to a depression of the endocochlear potential induced by the relatively hypoxic state of the fetus. The hypoxic state would lead to a reduced transduction current in the hair cells in response to a stimulus and an elevated hearing threshold. At birth, with the shift to pulmonary oxygenation, the neonate becomes normoxic, the endocochlear potential rapidly reaches near maximal levels and threshold is improved.

Animals↗
PubMedDate not supplied

The acoustic reflectometer as a screening device: a comparison.

Sixty children (120 ears) were evaluated using reflectometry, pure tones, immittance, otologic examination, and pure-tone air and bone conduction thresholds. Comparisons were made between the various screeners. Reflectometry was found to be the least sensitive and the least specific of the procedures. Results were then examined within each diagnostic category to determine test agreement with the otologists' judgments. The reflectometer categorization was found to be inconsistent with the otologic findings. Finally, the reflectometer was compared to each of the other screener results and pure-tone thresholds. The test results were significantly correlated but showed high over- and under-referral rates for the reflectometer. Seventy-eight children and adults (156 ears) were screened in a second study. Again, the acoustic reflectometer did not perform adequately as a general screening tool. When only cases of middle ear effusion were screened, the acoustic reflectometer did not perform as well as immitance.

Acoustics↗
PubMed1999

Long-term sensorineural hearing deficit following radiotherapy in patients suffering from nasopharyngeal carcinoma: A prospective study.

BACKGROUND: This was a prospective study to evaluate the effect of radical external irradiation on inner ear function after treatment of nasopharyngeal carcinoma. METHODS: Pure tone audiograms were performed at regular intervals before, after, and up to 4.5 years following completion of radiotherapy. RESULTS: Two hundred ninety-four patients (526 ears) were included. Within 3 months after radiotherapy, deterioration of bone conduction threshold at 4 kHz and pure tone average (average of 0.5 kHz, 1 kHz, and 2 kHz) were noted in 164 ears (31%) and 75 ears (14%), respectively. Patients older than 50 years and ears with threshold below 60 dB at 4 kHz before radiotherapy were significant factors (p < 0.01 and p < 0. 001) associated with a 4 kHz loss. In 40% of these ears, recovery was evident at 2 years. With follow-up for 4.5 years, the probability of significant threshold deterioration increased with time. CONCLUSION: Sensorineural hearing loss started soon after radiotherapy. Early changes could be reversible while the probability of persistent hearing loss continued to increase.

Adolescent↗
PubMed1982

The enzymatic mechanism of the otospongiotic disease and NaF action on the enzymatic balance.

Extensive research on enzymes led to the discovery of the innermost mechanism of the otospongiotic disease. The authors present the results of multiple correlations made from February 1976 to September 1980 on 648 samples of perilymph taken during stapedectomies performed on otosclerotic patients. We studied microdosages of three selected enzymes--trypsin, alpha 1 antitrypsin, and alpha 2 macroglobulin--in each of the samples and their relationship with cochlear deterioration expressed in dBs of bone conduction decrease in pure-tone audiometry testing. This study allowed us a better knowledge of the enzymatic mechanism of the otospongiotic disease, based on the previously reported trypsin-alpha 1 antitrypsin balance, but in which alpha 2 macroglobulin appears to play a role as essential as that of alpha 1 antitrypsin. This enzymatic mechanism explains NaF efficiency, which is due in fact to a double action: not only direct trypsin inhibition, but also an overall reduction in enzymatic values in the perilymph of otospongiotic/otosclerotic patients. Current studies could lead to the possibility of future NaF replacement by proteinase inhibitors either of microbial origin, under study by Japanese researchers, or even of synthetic origin, which should be investigated. In fact, the role of NaF therapy could already be taken over by diphosphonates currently under study.

Audiometry, Pure-Tone↗
PubMed2006

Perioperative recordings of vestibular-evoked myogenic potentials in otosclerosis.

OBJECTIVES: The aim of the present study was to investigate saccular function in patients with otosclerosis. Furthermore, the influence of stapedotomy on the vestibular-evoked myogenic potentials (VEMPs) should be demonstrated. STUDY DESIGN: Prospective study. SETTING: Tertiary referral center. METHODS: Bone-conducted tone-burst-evoked VEMPs were measured in 23 patients (25 ears) with unilateral or bilateral otosclerosis preoperatively and postoperatively. RESULTS: Preoperatively, VEMPs could be recorded in 11 ears (44%). There was no statistically significant correlation among the extent of preoperative sensorineural hearing loss, age, and VEMP measurements. Postoperatively, VEMPs were found in 14 ears (56%). In three cases (12%), VEMPs reappeared after surgery. The rare cases of preoperative vertigo could not be correlated to the nonappearance of VEMPs. CONCLUSION: Stapedotomy surgery does not influence VEMPs, implying that the saccular receptors are not injured by surgery. Moreover, in some cases, the elicitability of VEMPs was improved by stapedotomy surgery. Seemingly, otosclerosis can influence the generation of VEMPs most probably due to an involvement of the otolith organ's saccular receptors. No correlation was found between the clinical occurrence of vertigo and the elicitability of VEMPs.

Adult↗
PubMedDate not supplied

Sensorineural hearing loss in chronic ear surgery.

The author's series of 3000 consecutive operations of tympanoplasty from 1960 to 1975 were reviewed in regard to the occurrence of sensorineural hearing loss as a consequence of the surgical procedure. Worsening of bone conduction thresholds by 10 dB through the frequencies 500 to 4000 cps, or a 10% reduction in speech discrimination scores were considered significant. Whereas in transcanal tympanoplasty the incidence of cochlear damage was greater in ears when initially the ossiculare chain was incomplete, by contrast in combined approach tympanoplasty the risk was greater when the chain was intact initially. It was concluded that cochlear trauma was usually due to 1) the hydraulic effect of excessive stapes manipulation during the removal of disease, and 2) the development of a perilymph fistula. The unpredictable predisposing threat of cochlear fragility due to genetic and inflammatory factors was emphasized and the poor results of tympanoplasty in tympanosclerosis were underlined. The current methods of treating sensorineural hearing loss after tympanoplasty were enumerated and discussed. It was concluded that although those aimed at improving labyrinthine circulation had theoretical backing, there is as yet little experimental or clinical evidence to support the claims of their protagonists.

Bone Conduction↗
PubMed1995

Functional development of auditory sensitivity in the fetus and neonate.

The human fetus responds to sound stimuli while still in utero. The rat and cat begin to hear only after birth. Therefore neonatal rat and cat are used as models of the development of auditory sensitivity in the human fetus. The inner ear of rat responds to stimuli delivered directly to it (bone conduction) before the middle ear can conduct sounds to the inner ear. During this period, middle ear development involves mesenchyme resorption, ossicular hardening and opening of the external canal. The latter stages of inner ear development involve increased magnitude of the endocochlear potential which augments cochlear transduction and the active cochlear amplifier. These developmental stages are probably controlled by thyroid hormone which activates several genes leading to the synthesis of proteins and enzymes required for the structural and functional maturation of the ear. This likely includes the Na+,K(+)-ATPase of the stria vascularis which generates the endocochlear potential. The magnitude of the endocochlear potential is dependent on oxygen supply so that the human fetus in utero whose blood carries less oxygen than the newborn has a hypoxia-induced sensorineural hearing loss. Upon birth and transition from placental to pulmonary oxygenation, the oxygen content of blood is increased, the magnitude of the endocochlear potential is elevated and auditory sensitivity is enhanced.

Acoustic Stimulation↗
PubMed2006

A systematic review of the nonacoustic benefits of bone-anchored hearing AIDS.

OBJECTIVE: This study completed an evidence-based practice systematic review of the nonacoustic benefits for adult patients receiving bone-anchored hearing aid(s) (BAHAs) relative to other forms of amplification (i.e., none, bone-conduction hearing aids [BCHAs], or air-conduction hearing aids [ACHAs]). DESIGN: Systematic review. METHODS: ComDisDome and PubMed were used to perform a comprehensive search for studies that were of at least level III of evidence. Three independent reviewers completed the search, quality assessment, and data extraction. RESULTS: Out of 28 studies, seven studies were identified, three of which were prospective and four of which were retrospective within-subject comparison designs. Nearly all of the studies were of small sample size and/or limited methodological quality, primarily because of logistics (e.g., heterogeneity of subject samples and prior experience with amplification). CONCLUSIONS: The evidence identified in this review is limited regarding the nonacoustic benefits of BAHAs compared with unaided conditions or other types of amplification. Professionals should use caution when counseling patients about the quality of life (QOL) benefits of these devices. Routine use of QOL outcome measures and standardized methods for reporting findings are critical in demonstrating the nonacoustic benefits of BAHAs.

Adolescent↗
PubMed1998

Prevalence and etiology of unilateral sensorineural hearing impairment in a Finnish childhood population.

A retrospective study was undertaken on the prevalence and etiology of unilateral sensorineural hearing impairment (> 25 dB at 0.5-4 kHz, including mixed hearing impairments with bone conduction thresholds > or = 25 dB) among children born between 1972 and 1986 in a province of eastern Finland. Only patients who had been diagnosed before the age of 10 years were included. A total of 84 children with such an unilateral hearing loss were identified, with prevalence of 1.7 per 1000 live births. A significant decline from the prevalence of 2.2 per 1000 in the 1970s to the prevalence of 1.2 per 1000 in the 1980s was observed, which was mainly due to the disappearance of hearing losses caused by mumps and measles in the 1980s and the decrease in cases attributed to otitis media. In agreement with some previous studies, a considerable male predominance was present. Thirty-five percent of the hearing losses were profound (> 95 dB) and 15% were severe (71-95 dB). Etiology of the hearing impairment was estimated as genetic in 2%, congenital non-genetic in 12%, delayed-onset non-genetic in 35% and remained unknown in 51%.

Audiometry↗
PubMed1989

High-frequency monitoring using an electrostimulation audiometer.

Electrostimulation audiometry can provide high-frequency bone-conduction threshold measurements. To evaluate the use of such an audiometer in monitoring hearing, the following areas were investigated. (1) The variability and repeatability of threshold measurements. (2) To see if the instrument could be used on the ward where the patient would have to wear ear plugs to attenuate background noise, the effect of occluding the ears was assessed. (3) The applicability of the instrument to the range of patients in whom monitoring would be appropriate, specifically the relationship between the patient's age and the effective upper frequency limit of the audiometer. The data showed a variability in threshold measurement that is quite comparable with that obtained with conventional audiometry but which became smaller at frequencies of 12 kHz and higher. There was no overall effect on the threshold of occluding the ears, which meant that the instrument can be used to monitor a non-isolated environment such as a ward. The effective cut-off frequency was about 9 kHz for patients aged 55 years, and so the use of an electrostimulation audiometer to monitor high-frequency auditory thresholds is restricted to younger patients.

Adult↗
PubMed1985

Toward a standard for hearing conservation for underwater and hyperbaric environments.

Exposure of divers to intense noise in water is increasing, yet no general hearing-conservation standard for such exposures exists. This paper summarizes three theories of underwater hearing, the tympanic, bone-conduction, and dual path theories, and reviews empirical data in order to identify some requirements such a standard must meet. Among problems considered are hearing sensitivity in water, the frequency and dynamic ranges of the water-immersed ear, and non-auditory effects of underwater sound. It was concluded that no well-developed theoretical basis exists for extrapolating current hearing-conservation standards for air-borne noise to the underwater situation; the existing empirical evidence, except within the frequency range of 1.5-3.5 kc/s, is too scant to predict what levels of underwater noise would be safe for divers; the empirical data on underwater hearing suggest that the frequency range covered by an appropriate standard must be much broader, for both low and high frequencies, than is the case in air; in order to establish an appropriate standard, further research is required on the dynamic range of the ear in water; problems must be solved with shifts in the resonance frequency of the ear consequent to the introduction of helium-oxygen mixtures or other exotic gases and pressures during dry-helmet diving or during simulated underwater excursions in dry hyperbaric chambers; underwater noise exposure may involve hazards to other body systems than the ear; and some noise exposure conditions may interfere with job performance of divers.

Atmospheric Pressure↗