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PubMed2000

Ossiculoplasty: autogenous bone grafts, 34 years experience.

A series of 785 bone grafts between the tympanic membrane and head of the stapes were performed between 1964 and 1998. Ears were divided into 'normal tympanic membrane', 'stage I' and 'stage II' groups, in which the averages of the last postoperative air-bone gaps were 13.2, 18.7 and 18.1 dB, respectively (revision operations included). In the same order 43%, 26% and 23% of the ears showed air-bone gaps equal to or smaller than 10 dB; 85%, 61% and 67% equal to or smaller than 20 dB. Failures specific to the bone columella necessitated nine revision operations (eight for osseous fixation and one for atrophy). There have been no extrusions so far. Although, in the light of the literature the results are acceptable there is room for improvement.

Adolescent↗
PubMed2000

Bone-anchored hearing aid: quality of life assess by glasgow benefit inventory

INTRODUCTION: The bone-anchored hearing aid (BAHA) uses the system of osseointegration described by Branemark. It is a well-established mode of treatment and many studies show the audiological benefit, but none have assessed the benefit to the quality of life of patients who underwent this surgical intervention. This study uses the validated Glasgow Benefit Inventory (GBI) to quantify the changes in quality of life. The GBI is a specific patient-orientated questionnaire designed to look at the changes in health status secondary to an ORL intervention.1 The GBI gives an overll scorek, but also subscores of general, social and physical benefits. METHOD: Sixty consecutive BAHA patients were enrolled in the study. The male: female ratio was 1 : 26, with a mean age of 45 years. The most common indication was hearing loss secondary to mastoid disease/surgery followed by congenital atresia and chronically discharging ear. The mean bone conduction of the better ear was 19 dB and the mean conductive loss across the speech frequencies was 58 dB. Only patients who were fitted with the classic model were included in the study. RESULTS: The response rate was > 70%, which is high and adds weight to the results. The general benefit score was + 40 which is comparable to middle ear surgery, but just below benefit from chochlear implantation. The social benefit was + 27 with only + 10 for the physical score. This pattern mirrors that reported for other ear interventions. CONCLUSION: This paper is the first to demonstrate that there is significant quality of life benefit from BAHA surgical intervention as measured by the GBI.

Journal Article↗
PubMed2002

Difficult paediatric intubation when fibreoptic laryngoscopy fails.

We report an unusual problem with fibreoptic bronchoscopy in an 8-year-old girl with Negar syndrome. She had a history of difficult airway since birth, and had undergone mandibular distraction for severe obstructive sleep apnoea when she was aged 2 years. Nagar syndrome is a Treacher-Collins like syndrome with normal intelligence, conductive bone deafness and problems with articulation. The patients have malar hypoplasia with down slanting palpebral fissures, high nasal bridge, micrognathia, absence of lower eyelashes, low set posteriorly rotated ears, preauricular tags, atresia of external ear canal, cleft palate, hypoplasia of thumb, with or without radius, and limited elbow extension. Protracted attempts with a fibreoptic bronchoscope failed to visualize the glottis, and this was only possible when the tube was guided to the larynx by blind nasal intubation. Apparently, the healing of the wounds for the mandibular distraction in the mandibular space on the inside of the rami of the mandible had caused differential fibrosis on either side of the hyoid, leading to a triplane distortion of the larynx with a left shift, clockwise rotation to a 2-8 o'clock direction and a slight tilt towards the left pharyngeal wall. The large epiglottis overlying this had precluded a view of the larynx. Finally, the older technique of breathguided intubation facilitated fibreoptic bronchoscopy to achieve tracheal intubation.

Bronchoscopy↗
PubMed2000

[Detection of central auditory compensation in unilateral deafness with functional magnetic resonance tomography].

BACKGROUND: Functional magnetic resonance imaging (fMRI) is a noninvasive method to detect focal brain activity at high spatial resolution. Acoustic stimulation induces an increase of regional cerebral blood flow in the primary auditory cortex. This entails an increased concentration of diamagnetic oxyhemoglobin in the capillaries and the venous system. The resulting decrease of the local magnetic susceptibility was detected as a signal increase in T2*-weighted images. The central auditory pathways predominantly cross to the contralateral hemisphere in normally hearing subjects. The aim of the present study was to investigate the primary auditory cortex after acoustic stimulation in unilateral deaf patients using fMRI. METHODS: Magnetic resonance images were acquired on a 1.5 T Siemens Vision scanner. For fMRI, a single shot gradient recalled, echo planar imaging (EPI) sequence with decreasing excitation order was used, allowing the aquisition of 9 slices within 1.8 s. The 9 slices covered a slab of 3.6 cm in cranio-caudal extension in the region of the temporal lobes. For statistical processing of the raw image data the SPM96 software package was used. A p-value of p < 0.01 was applied to differentiate between activated and non-activated. The resulting functional activation maps were superimposed onto the EPI scan. The number of activated pixels was used to quantitate the cortical response upon acoustic stimulation. Stimulation consisted of a 1000-Hz sine tone (100 dB SPL at the distal end of the head phone, pulsed at 6 Hz) to which the patients were asked to listen passively. A piezoelectric loudspeaker was mounted on the subject table and connected to a plastic tube system leading to a combination of bilateral ear- and headphones. Auditory paradigms require disentangling experimental excitation from the scanner noise that approximates 90 dB. Headphones suppress noise by approximately 30 dB. To decrease the acoustic background-to-stimulation ratio and to keep background noise constant during stimulation and resting, we employed short scanning (1.8 s) and long resting periods (10.2 s; TR = 12 s). This acquisition mode allows sufficient recovery during off-periods and sufficient excitation during on-periods. 14 unilateral deaf patients were examined. The mean duration of deafness was 22.5 years. RESULTS: Acoustic stimulation of the deaf ear revealed only weak cortical activation which could be explained by sound transmission via bone conduction to the other ear. A significant increase of BOLD (blood oxygen level dependent)-activation in the primary auditory cortex could be demonstrated in all patients after stimulation of the hearing ear. However, remarkable individual differences were noticed concerning the absolute number of activated pixels. The lateralization ratio was calculated by the number of activated pixels on the hearing side divided by the number of activated pixels on the deaf side. A mean lateralization ratio of 0.9 (Stdv +/- 0.6) was found. The mean lateralization ratio for patients with a right deaf ear (n = 8) and those with a left deaf ear (n = 5) was 1.1 (Stdv +/- 0.7) and 0.6 (Stdv +/- 0.3) respectively. However, the difference was not significant (Wilcoxon test: p = 0.08). CONCLUSIONS: Central-auditory compensation by bilateral cortical activation was demonstrated in unilateral deaf patients. Moreover, a tendency towards a dominance of the left primary auditory cortex was found, although the difference between both hemispheres was not significant. The lateralization ratio in unilateral deaf patients is similar to findings after binaural stimulation in normally hearing subjects.

Acoustic Stimulation↗
PubMed1996

[In situ sound pressure measurement in a professional violinist with bilateral tinnitus].

BACKGROUND: A case of a professional violinist suffering from a bilateral tinnitus is presented. The musician reported the tinnitus to be louder and more straining when playing his Vuillaume violin (France 1840) as compared with his Carcassi violin (Italy 1763). CASE REPORT: In the 42-year-old musician, audiometry revealed a normal hearing threshold in the right ear and a slight hearing loss in the left ear of up to 20 dB between 2 kHz and 8 kHz. Transitory evoked otoacoustic emissions could only be measured in the right ear. The tinnitus could be masked (distance type); residual inhibition was only seen in the right ear. By sound intensity measurements in both external auditory canals, the different sound spectra of both violins could be demonstrated. When playing with "forte" intensity, sound pressure reached peaks of over 90 dB. The tinnitus was ameliorated by lidocaine infusions. DISCUSSION AND CONCLUSIONS: The different sound spectra of both violins may be the reason for the enhancement of the musician's tinnitus. Interference of air and bone-conducted sound could lead to a cochlear overlap and thus influence the tinnitus although such a phenomenon can not be verified. It was previously reported that high-pitched instruments may cause tinnitus sensations in performing musicians. A review of the literature surprisingly reveals that although professional musicians are exposed to sound pressure levels that may cause hearing impairment, only very few do develop one. This fact has to be taken into account whenever an occupational disease is suspected.

Adult↗
PubMed1995

[Screening program for selection of hearing loss in newborn infants instituted by the European Community].

Early identification of hearing impairment in children poses a major problem for clinical research and development. In the last two years we determined the hearing sensitivity of 1202 newborns, small infants and children. 52.4% of the children exhibited risk factors for hearing impairment in their medical history. The majority of children was referred to our department by pediatricians (52%), who first suspected hearing impairment, 40% by parents, 3.5% by otolaryngologists, 3% by educators, and 1.5% by general practitioners. The following examinations were performed: transiently evoked otoacoustic emissions (TEOAE), impedance audiometry, auropalpebralreflex, behavioral observation audiometry, and, if necessary, auditory brain stem response (ABR) with air and bone-conducted clicks as well as frequency-following responses at 500 Hz tone burst. In 378 children TEOAE were recorded on both sides, in 151 at least on one side. These results were confirmed by the other techniques. Only three children presented false negative results of TEOAE on one side. Two of these children had a middle ear effusion and a threshold of 35 dB, one had retrocochlear hearing loss. The absence of TEOAE in both ears in 155 children as well as in one ear in 16 children was detected by ABR. Seventy-seven patients showed no response on both sides, 25 on one side, although a hearing impairment more than 25 dB could not be verified by ABR. This high number of false positive results is explained in 77 cases (76%) by a middle ear dysfunction during the recording of TEOAE, when ABR was performed following adenotomy and paracentesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

[The monochord, its path from Pythagorean musicology to testing the upper auditory tone limit. Pictures from the history of otorhinolaryngology, represented by instruments of the Ingolstadt German Medical History Museum].

The monochord consists of a frame with a string or pianowire stretched across it. The length of the wire can be varied by a movable bridge. The string or wire is plucked, hit, or bowed, producing transverse vibrations. In this mode the number of vibrations per second is dependent on the length, tension, and thickness of the string. In ancient times, the Pythagoreans used such an instrument to study the natural laws underlying musical intervals; in the 19th century it also served for various other physical experiments. F. A. Schulze, physicist in Marburg, Germany, introduced the monochord for testing the upper tone limit in 1908. He produced longitudinal vibrations by rubbing the wire with a piece of felt moistened with benzol. The vibrations of this mode are dependent only on the length of the wire and the elasticity of the material; they are independent of its tension and thickness. H. J. L. Struycken, otologist in Breda, Holland, presented an improved type of monochord in 1910 which also allowed testing bone conduction. K. L. Schaefer, physiologist in Berlin, modified Struycken's instrument in such a way that bowing the wire or hitting it with a small hammer also produced transverse vibrations. This enlarged the range of tones in the lower region. In this combined version the monochord was an indispensable piece of hearing testing equipment before the era of electronic audiometers. The technical development and clinical application of the monochord is described in detail.

Audiometry, Pure-Tone↗
PubMed2005

Coenzyme Q-10 treatment of patients with a 7445A--->G mitochondrial DNA mutation stops the progression of hearing loss.

CONCLUSION: CoQ 10 may be helpful in delaying the progression of hearing loss in patients with the 7445A-->G mitochondrial mutation. Objective. To assess the effect of an antioxidant drug (Coenzyme Q-10) on the hearing level of patients with the mitochondrial DNA 7445A-->G mutation and associated sensorineural hearing loss (SNHL). Material and methods. We identified three patients with bilateral non-syndromic SNHL harboring the mitochondrial 7445A-->G mutation. Two patients had a family history of hearing loss with a strong matrilineal inheritance. The other patient did not have a family history of hearing loss. Two patients (1 with familial and 1 with sporadic SNHL) received treatment with 75 mg of Coenzyme Q-10 (CoQ10) twice a day for 1 year. The remaining patient with a familial form of hearing loss did not agree to take the treatment. Average bone conduction pure-tone thresholds for 0.5, 1, 2 and 4 kHz were obtained before and after diagnosis of mitochondrial hearing loss, and before and after treatment with CoQ10. Results. CoQ10-treated patients did not show any additional deterioration of their SNHL after 12 (familial case) and 13 months (sporadic case). The progression rate of SNHL was 6 dB/year in the 2 years prior to initiation of treatment in the familial case who received CoQ10 treatment. One year after being diagnosed with mitochondrial hearing loss, the patient who refused CoQ10 treatment exhibited an 11-dB deterioration of his hearing thresholds. There were no side-effects related to treatment with CoQ10.

Adult↗
PubMed2001

State of the art neonatal hearing screening with auditory brainstem response.

The purpose of this paper is to briefly review some of the aspects of the auditory brainstem response (ABR) that are important in its use as a method of screening and assessing hearing in the neonate. The paper starts by considering the technical limitations of click ABR and explores the alternative electrophysiological methods. It then considers where ABR is required in the screening of neonates. The role of bone conduction ABR in estimating the conductive component of any hearing loss is discussed. Finally, the ability of the neonatal ABR to predict the long-term audiometric outcome of permanently hearing-impaired children is considered.

Evoked Potentials, Auditory, Brain Stem↗
PubMed2001

Immunohistochemical study of clinical skin-penetrating titanium implants for orthopaedic prostheses compared with implants in the craniofacial area.

The technique of using osseointegrated bone-anchored percutaneous titanium implants in the rehabilitation of patients with amputated limbs has recently been introduced at the Brånemark Osseointegration Centre in Göteborg. The new method is based on an implantation technique that is well-established for anchorage of bone-conductive hearing aids and craniofacial prostheses. The soft tissues around skin-penetrating titanium implants used to anchor orthopaedic prostheses were evaluated histochemically using quantitative analyses. The implants had been in clinical use for between 6 to 24 months. The number of inflammatory cells was higher in the area close to the interface than in the area distant from the skin-penetrating site, and higher than in the corresponding controls. The current data was also compared with corresponding data from tissue around skin-penetrating craniofacial implants. The number of inflammatory cells was lower in the orthopaedic samples than in the craniofacial specimens. We conclude that skin-penetration of orthopaedic implants is as safe as when titanium implants are used for craniofacial rehabilitation, which is a clinically well-established procedure.

Adult↗
PubMed1999

The epidemiology of hearing impairment in an Australian adult population.

BACKGROUND: This study measured the prevalence of hearing impairment, and major demographic factors that influence the prevalence, in a representative South Australian adult population sample aged > or = 15 years. METHODS: The study group was recruited from representative population surveys of South Australians. Participants in these surveys who reported a hearing disability were then recruited to an audiological study which measured air and bone conduction thresholds. In addition a sample of those people who reported no hearing disability were recruited to the audiological study. RESULTS: The data reported in this study are the first in Australia to assess the prevalence of hearing impairment from a representative population survey using audiological methods. The data show that 16.6% of the South Australian population have a hearing impairment in the better ear at > or = 25 dBHTL and 22.2% in the worse ear at the same level. The results obtained in this representative sample compare well with those obtained in the British Study of Hearing, although some differences were observed. CONCLUSIONS: Overall, there are only a few studies worldwide that have audiologically assessed the impairment of hearing from a representative population sample. The overall prevalence of hearing impairment in Australia is similar to that found in Great Britain, although there are some differences between the estimates of severity of impairment and some sex differences. The corroboration of the two studies reinforces the status of hearing impairment as the most common disability of adulthood. The present study also showed that there are a large number of Australians who may benefit from a more systematic community-based rehabilitation programme including the fitting of hearing aids. Secondly, the study identified the need for health goals and targets for hearing to be based on an epidemiological approach to the problem.

Adolescent↗
PubMed1998

Prevalence of hearing loss in older adults in Beaver Dam, Wisconsin. The Epidemiology of Hearing Loss Study.

There are no recent population-based data on the prevalence of hearing loss in older adults using standard audiometric testing. The population-based Epidemiology of Hearing Loss Study was designed to measure the prevalence of hearing loss in adults aged 48-92 years, residing in Beaver Dam, Wisconsin. Hearing thresholds were measured with standardized protocols using pure-tone air- and bone-conduction audiometry in sound-treated booths. The examination also included an otoscopic evaluation, screening tympanogram, and a questionnaire on hearing-related medical history, noise exposure, other potential risk factors, and self-perceived hearing handicap. Of the 4,541 eligible people, 3,753 (82.6%) participated in the hearing study (1993-1995). The average age of participants was 65.8 years, and 57.7% were women. The prevalence of hearing loss was 45.9%. The odds of hearing loss increased with age (odds ratio (OR) = 1.88 for 5 years, 95% confidence interval (CI) 1.80-1.97) and were greater for men than women (OR = 4.42, 95% CI 3.73-5.24). The male excess of hearing loss remained statistically significant after adjusting for age, education, noise exposure, and occupation (OR = 3.65). These results demonstrate that hearing loss is a very common problem affecting older adults. Epidemiologic studies are needed to understand the genetic, environmental, and sex-related determinants of age-related hearing loss and to identify potential intervention strategies.

Adult↗
PubMed2005

Enhanced erythropoiesis mediated by activation of the renin-angiotensin system via angiotensin II type 1a receptor.

Although clinical and experimental studies have long suggested a role for the renin-angiotensin system (RAS) in the regulation of erythropoiesis, the molecular basis of this role has not been well understood. We report here that transgenic mice carrying both the human renin and human angiotensinogen genes displayed persistent erythrocytosis as well as hypertension. To identify the receptor molecule responsible for this phenotype, we introduced both transgenes into the AT1a receptor null background and found that the hematocrit level in the compound mice was restored to the normal level. Angiotensin II has been shown to influence erythropoiesis by two means, up-regulation of erythropoietin levels and direct stimulation of erythroid progenitor cells. Thus, we conducted bone marrow transplantation experiments and clarified that AT1a receptors on bone marrow-derived cells were dispensable for RAS-dependent erythrocytosis. Plasma erythropoietin levels and kidney erythropoietin mRNA expression in the double transgenic mice were significantly increased compared with those of the wild-type control, while the elevated plasma erythropoietin levels were significantly attenuated in the compound mice. These results provide clear genetic evidence that activated RAS enhances erythropoiesis through the AT1a receptor of kidney cells and that this effect is mediated by the elevation of plasma erythropoietin levels in vivo.

Angiotensin II↗
PubMed2002

Otological and audiological outcomes five years after tympanostomy in early childhood.

OBJECTIVE: Ventilation tubes in the treatment of otitis media in young children remain controversial. Despite abundant research, few prospective long-term follow-up studies have included even a minority of patients under 1 year old. We investigated long-term otological and audiological outcomes in children with recurrent acute otitis media and otitis media with effusion, who were treated early with ventilation tubes. STUDY DESIGN: Prospective follow-up. METHODS: Three hundred five children under 17 months of age received a primary tympanostomy in the Central Hospital of Central Finland (Jyväskylä, Finland), and those 281 (92.1%) who were monitored prospectively for 5 years made up the study group. At the final examination, pneumatic otoscope and otomicroscope were used and pure-tone audiometric thresholds of air and bone conduction were measured to define the hearing levels (mean of 0.5, 1.0, and 2.0 KHz thresholds). RESULTS: Of ears, 67.3% were healed, 7.1% had a retraction of tympanic membrane in pars flaccida and 9.6% in pars tensa, 7.5% had an ongoing otitis media with effusion, 3.9% had a ventilation tube in place, and 4.6% had a tympanic membrane perforation with mean hearing levels of 7.6, 9.0, 16.0, 18.5, 10.5, and 17.7 dB, respectively. CONCLUSIONS: Hearing in general was well preserved, and no ear presented with adhesive otitis media or cholesteatoma. Adverse otological and audiological outcomes of these young children did not exceed those presented by others for older counterparts. Tympanic membrane perforations, ongoing otitis media with effusion, and pars tensa retractions were causes of mild conductive hearing loss. Because one third of ears continued to have middle ear disease or sequelae, we emphasize the proper follow-up and restoration of middle ear ventilation with repeat ventilation tubes if not otherwise achieved.

Acute Disease↗
PubMed2004

Bilateral bone-anchored hearing aids (BAHAs): an audiometric evaluation.

OBJECTIVES: Since the technique to implant bone-anchored hearing aids (BAHAs) with the use of osseointegrated implants was developed in 1977, more than 15,000 patients have been fitted with BAHAs worldwide. Although the majority have bilateral hearing loss, they are primarily fitted unilaterally. The main objective of this study was to reveal benefits and drawbacks of bilateral fitting of BAHAs in patients with symmetric or slight asymmetric bone-conduction thresholds. The possible effects were divided into three categories: hearing thresholds, directional hearing, and binaural hearing. STUDY DESIGN: Prospective study of 12 patients with bilateral BAHAs. METHODS: Baseline audiometry, directional hearing, speech reception thresholds in quiet and in noise, and binaural masking level difference were tested when BAHAs were fitted unilaterally and bilaterally. RESULTS: Eleven of the 12 patients used bilateral BAHAs on a daily basis. Tests performed in the study show a significant improvement in sound localization with bilateral BAHAs; the results with unilateral fitting were close to the chance level. Furthermore, with bilateral application, the improvement of the speech reception threshold in quiet was 5.4 dB. An improvement with bilateral fitting was also found for speech reception in noise. CONCLUSIONS: Overall, the results with bilateral fitted BAHAs were better than with unilaterally fitted BAHA; the benefit is not only caused simply by bilateral stimulation but also, to some extent, by binaural hearing. Bilateral BAHAs should be considered for patients with bilateral hearing loss otherwise suitable for BAHAs.

Adult↗
PubMed2004

Vestibular nerve section versus intratympanic gentamicin for Meniere's disease.

OBJECTIVES/HYPOTHESIS: Vestibular nerve section and transtympanic gentamicin administration are procedures with proven efficacy in the treatment of vertigo associated with Meniere's disease refractory to medical management. Hearing loss is a known complication of each of these procedures; however, there has not been a report of hearing results of both treatments from a single institution. STUDY DESIGN: Retrospective review. METHODS: Review was made of 25 patients undergoing gentamicin injection and 39 patients undergoing vestibular nerve section for Meniere's disease. Rate of vertigo control and pretreatment and post-treatment pure-tone average values and speech discrimination scores were reported. RESULTS: The mean preoperative pure-tone average for patients having vestibular nerve section was 47.2 dB, with a speech discrimination score of 75.4%. In these patients, the postoperative pure-tone average was 49.1 dB and the speech discrimination score was 75%. Patients undergoing gentamicin injection had a mean pretreatment pure-tone average of 55.9 dB and a speech discrimination score of 62%. The post-treatment pure-tone average and speech discrimination score for the gentamicin group were 68.8 dB and 49.3%, respectively. Five of 25 patients (20%) in the gentamicin treatment group and 1 of 39 (3%) in the vestibular nerve section treatment group had an increase in bone-conduction threshold greater than 30 dB. The amount of postprocedure hearing loss was significantly greater in the gentamicin treatment group (P =.006). Control of vertigo was good to excellent in 95% of the patients treated with vestibular nerve section and in 80% of the patients treated with gentamicin. CONCLUSION: Although vestibular nerve section and transtympanic gentamicin are both acceptable treatment options for vertigo associated with Meniere's disease, gentamicin causes a higher level of hearing loss related to treatment and vestibular nerve section has higher vertigo control rates.

Anti-Bacterial Agents↗
PubMed2003

Audiologic assessment in infants.

PURPOSE: The purpose of this review is to provide the reader with current information regarding the standards for audiologic assessment of infants and very young children. The nature of the appropriate test battery and the need for adjusting test procedures to meet the specific needs of infants and toddlers are emphasized. RECENT FINDINGS: The basic measures in the audiologic test battery include frequency-specific threshold tests by air and bone conduction, predicted by electrophysiologic measures when necessary; immittance measures including tympanometry and acoustic reflex using a high-frequency probe tone for infants under 4 months of age; and otoacoustic emissions. The ABR can be used with frequency-specific stimuli to predict the audiogram in newborns with a great deal of accuracy. Newer techniques, such as Auditory Steady State Response, are promising but need further study before they can be used reliably to predict hearing levels in infants. Finally, infants with hearing loss can be fit with amplification using prescriptive formulae, such as the Desired Sensation Level, which give appropriate hearing aid characteristics for infants based on their hearing thresholds. These fittings must be verified using objective electro-acoustic measures tailored to infants. SUMMARY: Infants failing newborn hearing screenings can be evaluated by audiologists to predict all necessary audiologic data and those found to have hearing loss can be fitted with appropriate amplification in the newborn period. Procedures must be carefully tailored to this age group.

Acoustic Impedance Tests↗