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[Causes and results of reoperations following stapedectomy].

The records of 145 patients who underwent revision stapedectomy were analysed to determine the causes of failure of the previous operation, the hearing results and the postoperative complaints. Displacement of the prosthesis was the most common cause of failure (49%). Other surgical findings, sometimes in combination, were a short prosthesis (35%), middle ear adhesions (23%), otosclerotic regrowth (14%) and eroded incus (10%). No specific cause of failure was identified in 6% of the revisions. Thirty-eight per cent of revision operations resulted in a hearing gain to a level less than 10 dB conduction loss and 61% to less than 20 dB. Slight sensorineural hearing loss after revision surgery occurred in 5%. 'Dead ears' were encountered in 2% as against 0.6% in the primary cases. Tinnitus was the most common complaint (21%) at the 3 week postoperative follow-up, declining to 7% four months postoperatively.

Adolescent↗

Percutaneous plating of lower limb long bone fractures.

We conducted a study on indirect reduction and percutaneous plating in the treatment of 22 cases (mean age 50.3, S.D. 18.5, range 18-88) of non-diaphyseal fractures of long bones of the lower limb mainly using the lateral tibial head buttress plate. All cases achieved radiological union and full weight bearing walking. No major malalignment resulted and only one Gustilo III-b compound fracture required bone grafting. None required revision surgery from problem with union. One case required revision in the early learning phase and another patient suffered wound complication from self-herbal application which required local flap surgery. The satisfactory functional results and the lack of soft tissue complications suggest that this method should be considered in metaphyseal fractures where intramedullary nails are not applicable.

Adolescent↗

Myringoplasty. A review of 472 cases.

We reviewed the records of 472 patients who had undergone myringoplasty during an 11-year period at the Otologic Medical Group. There was a statistically significant relationship between the size of the perforation and the degree of hearing impairment, but no relationship between the degree of impairment and the complaint of tinnitus. The majority of operations were performed using the lateral surface fascia grafting technique. Those 168 operations performed postauricularly were successful in closing the tympanic membrane perforation in over 97% of the cases and in reducing the conductive deficit to 10 dB or less in 88%. There were no total sensorineural impairments, although 3% of the patients developed a high tone sensorineural impairment. Blunting in the anterior sulcus and lateral healing of the graft were very uncommon. Canal skin was used as a graft in 16% of the patients. The graft take results and hearing results were less favorable than with fascia.

Adolescent↗

Development of auditory function in newborn infants revealed by auditory brainstem potentials.

Auditory brainstem potentials were recorded from scalp electrodes in 42 infants ranging in gestational age from 25 to 44 weeks. The latencies of the various potential components decreased with maturation. Wave V, evoked by 65-dB sensation level clicks, changed in latency from 9.9 msec at 26 weeks of gestation of 6.9 msec at 40 weeks of gestation. Central conduction times in the auditory pathway also decreased with maturation from 7.2 msec at 26 weeks to 5.2 msec at 40 weeks. The effects of brainstem and cochlear disorders on auditory brainstem potentials were noted in several abnormal infants. The application of all of these techniques could permit an objective definition of both normal and abnormal sensory processes in newborn infants.

Action Potentials↗

Round window atresia and its effect on sound transmission.

OBJECTIVE: To document isolated round window atresia and to discuss its impact on current theories of inner ear function. PATIENTS AND STUDY DESIGN: Retrospective analysis of isolated round window atresia suggesting an autosomal dominant inheritance pattern and review of current concepts of cochlear macromechanics. SETTING: Tertiary referral center. RESULTS: The unexpected finding of isolated round window atresia in two female patients of the same family was confirmed intraoperatively as well as postoperatively using high-resolution computed tomography. The current audiograms and the review of the literature highlight a mixed, but predominantly conductive, hearing impairment with thresholds at 30 to 40 dB. Implying that there is no pressure release mechanism for inner ear fluid displaced by the stapes footplate, a total conductive hearing loss would be expected. CONCLUSIONS: The rare finding of round window atresia can be overlooked at surgery because of insufficient exposure of the round window niche. High-resolution computed tomography confirms the round window obliteration. It seems that an alternative way of cochlear stimulation takes place besides the concept of fluid bulk shifting. Surgery seems not to guarantee favorable results.

Auditory Pathways↗

Otologic disease in turner syndrome.

OBJECTIVE: This study involved the assessment of the otologic and audiologic characteristics of a group of patients with Turner syndrome. STUDY DESIGN: Prospective study consisting of a questionnaire (77 of 123 responders) and an otologic and audiologic evaluation in patients with Turner syndrome (41 participants). SETTING: Tertiary academic medical setting. PATIENTS: Children, adolescents, and adults with Turner syndrome (median age, 24 yr). INTERVENTIONS: Otomicroscopy, audiometry, immittance measurements, and diagnostic imaging. RESULTS: Otologic disease is an important characteristic in Turner syndrome. Sixty-six percent of the patients studied via the questionnaire reported a history of chronic or recurrent middle ear disease. Analysis of audiometric data in 40 patients tested reveals an equal amount of normal ears (38.8%) and pure sensorineural ears (38.8%), each constituting approximately one-third of the patient population. Pure conductive losses represent only one-fifth (21.3%) of auditory abnormality encountered. CONCLUSIONS: Careful follow-up during early childhood of children with Turner syndrome is necessary to detect middle ear disease and prevent sequelae. However, long-term periodic review is mandatory even after resolution of middle ear disease to detect sensorineural hearing loss.

Adolescent↗

Effect of hearing aids on speech perception in noisy situations.

Hearing-impaired people often complain about poor speech intelligibility when they are in noisy surroundings. Several authors have published data suggesting that hearing aids add distortion to the signal and thus make speech less intelligible. Given the tendency of people to speak louder in competing noise, it means that some patients might understand better in such circumstances without an aid than with an aid. The present study investigated the effect of modern commercial hearing aids on the ability of patients to understand speech monaurally in noisy circumstances. The results in general showed speech to be equally understandable with and without an aid if the effects of presentation level (amplification) are excluded. The results, however, varied considerably between patients. Statistical analysis showed that the variance could be explained primarily by the degree of high-frequency loss and the slope of the audiogram. Patients with steep sloping audiograms understand better and patients with a conductive hearing loss component understand less in noisy circumstances with a hearing aid. Speech intelligibility in noisy situations did not correlate at all with the hearing loss averaged over the mid-frequencies (500, 1,000 and 2,000 Hz) but it did correlate with the high-frequency hearing loss (2,000 and 4,000 Hz) and the slope of the audiogram, indicating the importance of high-frequency emphasis in hearing aids.

Aged↗

Hearing and para-airport children.

Audiometric screening was carried out on 3,322 elementary and high school students living in the vicinity of Logan International Airport, Boston, in an effort to determine whether noise from aircraft had any measurable effect on their hearing. Followup examinations and additional data on children failing the screening examination made it possible to classify the hearing losses as conductive, sensorineural, or mixed. The incidence of bilateral sensorineural or mixed hearing loss in the group living directly under flight paths or immediately adjacent to runways was not significantly different from the overall average. In normal subjects, the average sensorineural gap, a newly defined measure of high-tone loss, was not found to be significantly affected by the degree or duration of exposure to aircraft noise.

Adolescent↗

Sonotubometry. An acoustical method for objective measurement of auditory tubal opening.

The sound conduction method for measurement of the Eustachian tube opening has been studied and modifications made in the test procedure to increase its easy performance and reliability. By holding the sound source near to the nostril, mounting the microphone into a circumaural ear defender and by feeding the output of the microphone through a filter with a very narrow bandwidth (3.16 Hz) many of the pitfalls of the sound conduction technique described earlier could be removed. Recording of the transfer function between the nasal tip and external auditory meatus and recording of the spectrum of swallowing sound revealed that the useful frequency rang for the measurements was upwards from 5--6 kHz. By using the three frequencies 6, 7 and 8 kHz the method showed tubal opening in 90 or 95% of normal ears depending on whether the minimum amplitude accetped was greater than or equal to 5 or 1--4 dB, respectively.

Acoustic Stimulation↗

Air conduction thresholds and secretory otitis media: a conventional and extra-high frequency audiometric comparison.

A comparison has been made of air conduction threshold changes up to 1 year after myringotomy, aspiration of middle ear fluid, and insertion of ventilation tubes in ten patients with bilateral and 12 with unilateral secretory otitis media (SOM). Pure tone air conduction thresholds have been analyzed in three frequency groups: low frequency (LF; 0.25 0.5, and 1 kHz), high frequency (HF; 2, 4, and 8 kHz), and extra-high frequency (EHF; 10, 12, 14 and 16 kHz). In the LF and HF ranges, significant improvement came during the first 24 hours after intubation, while in the EHF range, threshold lowering occurred gradually over the following 2 months. Possible explanations for these findings are discussed.

Adolescent↗

Symposium on hearing loss--the otolaryngologist's responsibility. Medical management of hearing loss.

Millions of Americans suffer hearing loss resulting in immense social and economic consequences. Hearing loss is merely a symptom or sign and the evaluation and management of afflicted individuals requires a thorough knowledge of etiologic factors and understanding of the underlying pathophysiology. Hearing loss is either conductive, sensorineural, or mixed. It may be congenital or delayed in onset, genetic or progressive or stable. Specific diagnosis should be sought in all cases with the objective being reversal of the hearing loss. Often definitive therapy is lacking yet prevention of progression, when possible; recognition of associated disorders, when present; compensation for disability, when applicable; epidemiologic study; genetic and psycho-social counseling; and habilitation and rehabilitation may still be initiated. A vigorous approach to the patient with hearing loss should be championed by the otolaryngologist.

Bone Conduction↗

Management of an "Ear Camp" for children in Namibia.

OBJECTIVE: In this publication, we present our experiences with managing an "Ear Camp" in northern Namibia, where the population is predominantly black. Medical coverage for ear problems is poor in this part of the country. METHODS: Within 10 days, 38 children (median age 12 years) were operated mainly for (sub) total defects of the tympanic membrane. In two cases, an open cavity had to be created because of a cholesteatoma. We performed a tympanoplasty type I in 18 cases and a tympanoplasty type III in 20 cases. Additionally, in 8 cases an antrotomy and in another 8 cases a mastoidectomy was performed. The ossicular chain was reconstructed with a titanium-PORP (14 cases), a titanium-TORP, interposition of the head of the malleus or a cartilage columella (one case each) or by placing the reconstructed tympanic membrane directly onto the head of the stapes (three cases). The tympanic membrane was reconstructed by the use of tragal cartilage with overlapping perichondrium in underlay-technique. RESULTS: Thirty-one children could be followed up. A defect of the tympanic membrane was found in five cases because of continuous purulent discharge. The average improvement of air conduction thresholds in the frequencies between 250 and 4000 Hz was 15 dB. CONCLUSIONS: Surgical techniques, antibiotic treatment and perioperative management have to be adapted to limited possibilities of pre-treatment and aftercare. As development aid should support people to look after themselves, we started to instruct local doctors with regard to pre- and postoperative care in ear surgery. Training of the local doctors will be continued in our next "Ear Camp" in 2004.

Adenoidectomy↗

The clinical utility of ipsilateral stapedius reflex tests.

Ipsilateral stapedius reflex testing has been evaluated in 166 patients. It proves of value in defining the state of an ear (1) opposite to a unilateral conductive loss; (2) the less hard-of-hearing ear in the presence of bilateral asymmetrical sensorineural hearing losses where the worse ear has sufficiently severe loss to prevent a contralateral reflex from being elicited; (3) in patients with absent contralateral acoustic reflexes at 500, 1000, and 2000 Hz; and (4) in suspected central lesions. The test is still bedevilled by artifacts which are produced in the ear rather than the machine; atypical results must be evaluated with extreme caution.

Acoustic Impedance Tests↗

Isolating the auditory system from acoustic noise during functional magnetic resonance imaging: examination of noise conduction through the ear canal, head, and body.

Approaches were examined for reducing acoustic noise levels heard by subjects during functional magnetic resonance imaging (fMRI), a technique for localizing brain activation in humans. Specifically, it was examined whether a device for isolating the head and ear canal from sound (a "helmet") could add to the isolation provided by conventional hearing protection devices (i.e., earmuffs and earplugs). Both subjective attenuation (the difference in hearing threshold with versus without isolation devices in place) and objective attenuation (difference in ear-canal sound pressure) were measured. In the frequency range of the most intense fMRI noise (1-1.4 kHz), a helmet, earmuffs, and earplugs used together attenuated perceived sound by 55-63 dB, whereas the attenuation provided by the conventional devices alone was substantially less: 30-37 dB for earmuffs, 25-28 dB for earplugs, and 39-41 dB for earmuffs and earplugs used together. The data enabled the clarification of the relative importance of ear canal, head, and body conduction routes to the cochlea under different conditions: At low frequencies (< or =500 Hz), the ear canal was the dominant route of sound conduction to the cochlea for all of the device combinations considered. At higher frequencies (>500 Hz), the ear canal was the dominant route when either earmuffs or earplugs were worn. However, the dominant route of sound conduction was through the head when both earmuffs and earplugs were worn, through both ear canal and body when a helmet and earmuffs were worn, and through the body when a helmet, earmuffs, and earplugs were worn. It is estimated that a helmet, earmuffs, and earplugs together will reduce the most intense fMRI noise levels experienced by a subject to 60-65 dB SPL. Even greater reductions in noise should be achievable by isolating the body from the surrounding noise field.

Adult↗

Revision stapedectomy.

The need for revision stapedectomy surgery still exists despite the many changes that have occurred in the surgical technique for the treatment of stapedial otosclerosis over the past 30 years. Sixty-six revision stapes operations were analyzed to determine the causes of failure of previously operated cases of stapedial otosclerosis, and to evaluate the hearing results following a revision stapedectomy. Failure was most often due to erosion of the incus (41%), displacement of the prosthesis from the incus (24%), or migration of the prosthesis from the center portion of the oval window (24%). Postoperative improvement of hearing was observed in 81% of ears operated on for a conductive hearing loss. Closure to within 10 dB, however, occurred in 61%. Two ears suffered a deterioration in the sensorineural hearing level following the revision surgery. Speech discrimination scores following revision surgery were improved in 5% of ears and unchanged in the remainder. Although the overall hearing results are less favorable than those seen in primary stapedectomy, revision stapedectomy surgery should continue to be offered to patients whose primary stapes surgery failed or whose initial good result declined over time.

Adult↗

A new modification of the Rinne test.

A modification of Rinne's test is described. The result of the test is dependent on many factors and in particular the force with which the tuning fork is applied to the mastoid process is important. Most authorities state that firm pressure should be used but the precise force required is inadequately defined. A modification of a standard tuning fork was therefore designed which allows measurement of the actual force used. 100 ears with confirmed conductive hearing losses were examined. Rinne's test was performed on each ear comparing three different forces. The forces used were 400 g (3.9 N) corresponding to light pressure, 2400 g (23.5 N) corresponding to firm pressure, and an intermediate and indeterminate force corresponding to normal clinical performance of the test. The optimum force in this study is 2400 g (23.5 N) force. This gives increased sensitivity, specificity and accuracy compared to lesser forces. More accurate measurement of the force used allows better reproducibility and more meaningful comparison of the results thus obtained.

Adult↗

[Evidence of otospongiosis obtained by computerized tomography. Does it compromise the post-stapedectomy auditory gain?].

To study the influence of tomographic otospongiosis/otosclerosis on the audiometric gain after stapedectomy, we evaluated 34 patients (mean age 39.9 years, S.D. 9.8) with otosclerosis and mixed hearing loss. We performed Computed Tomography (CT) with densitometry before stapedectomy and audiometry before and 4 weeks after the surgery. CT results were classified as compatible or not for otospongiosis (< 1000 UH) or for otosclerosis (> 2000 UH). According to the affected turns of the cochlea, the studies were classified in 3 groups. In 43% of the patients the CT showed otospongiosis. After stapedectomy, air conduction thresholds of the low (125-500 Hz), middle (500-2000 Hz) and high frequency bands (2000-8000 Hz) and for the air/bone gap were similar for the ears with or without otospongiosis (p > 0.05, ANOVA). However, patients with otospongiosis in all the cochlea showed the lowest audiometric gain for the high frequency band (p < 0.05 ANOVA). Evidence of otospongiosis evaluated just by CT has a low impact on the audiometric outcome after stapedectomy.

Adult↗

Malleus ankylosis: a clinical, audiometric, histologic, and surgical study of 123 cases.

OBJECTIVE: Malleus ankylosis is a cause of conductive hearing loss that can be difficult to assess, particularly in association with otosclerotic stapes fixation. The aim of this study is to seek the clinical and audiometrical features unique to this pathology. STUDY DESIGN: The study design was a review of malleus ankylosis cases and an analysis of functional results after ossiculoplasty. SETTING: The study was performed at Jean Causse Clinic in France. PATIENTS: The authors reviewed a series of 123 ears in 112 patients who underwent surgery for incudo-mallear ankylosis from January 1991 to September 1997. INTERVENTION: The surgical technique depends on the type of pathology encountered. In case of associated stapedial fixation, a stapedotomy with vein graft interposition and reconstruction with a total prosthesis will be performed during a same step. MAIN OUTCOME MEASURES: Clinical evaluation, preoperative and postoperative audiometrical evaluation, operative findings, histologic examination, and postoperative functional results. RESULTS: In our series, a postoperative air-bone gap smaller than 10 dB was obtained in 77% of cases. These results confirm the possibility of managing both pathologies in a single surgical step. CONCLUSION: Incudo-mallear ankylosis remains an unusual pathology but should be systematically assessed during surgery and preferably after separation of the incudo-stapedial joint. A preoperative diagnosis is difficult to ascertain; some audiometrical features allow a suspicion. In this series, it is shown that otosclerosis can be responsible for ankylosis as seems to be confirmed by the two cases presented in this study.

Adolescent↗