Prevalence of tympanogram asymmetries and fluctuations in otitis media with effusion: implications for binaural hearing

Long-term Effects of Unilateral and Bilateral Otitis Media and Myringotomy on Long-Latency Verbal and Non-Verbal Auditory-Evoked Potentials

Introduction  Otitis media (OM) is considered one of the most common reasons patients seek medical care in childhood. The fluctuating nature of hearing loss in cases of OM leads to irregular sound stimulation of the central auditory nervous system. Objectives  To analyze the long-latency auditory-evoked potential (LLAEP) by verbal and nonverbal sounds in children with a history of OM in the first six years of life. Methods  A total of 106 schoolchildren participated in the study, 55 females and 51 males, aged between 8 and 16 years, who were divided into 3 groups: the control group (CG), the bilateral experimental group (BEG), and the unilateral experimental group (UEG). All children underwent a complete audiological evaluation (audiometry, logoaudiometry and immitance testing) and an electrophysiological evaluation (LLAEP with toneburst stimulus - LLAEP-TB, and LLAEP with speech stimulus - LLAEP-S). Results  Both study groups (BEG and UEG) presented a statistically lower performance ( p  < 0.005) when compared with the CG regarding all of the electrophysiological tests with the prolongation of the latency values and decrease in the amplitude values: LLAEP-TB (BEG: latency - N1, P2, N2 [females] and P300, amplitude - N1 and P2), LLAEP-S (BEG: latency - P2 and N2 [females], amplitude - P2 /UEG: latency - P2 and P300, amplitude: N1 and P2). Conclusion  Children who had suffered secretory OM in the first six years of life and who had undergone myringotomy for the placement of a ventilation tube, either unilaterally or bilaterally, presented worse performance in their electrophysiological responses to verbal and nonverbal LLAEPs.

[On the terminology of auditory steady-state responses. What differentiates steady-state and transient potentials?]

BACKGROUND

Recording human auditory steady-state responses (ASSR) at different frequencies allows objective assessment of auditory thresholds. Common practice has been to record ASSR to pure tones that are sinusoidally modulated in amplitude and frequency. Recently, optimized chirp stimuli have been proposed to evoke transient as well as steady-state responses. Because of the resulting uncertainty about the different methods, this paper aims to reconsider the terminology of transient and steady-state responses.

METHOD

Two experiments demonstrate the smooth transition between transient and steady-state responses. In experiment 1, click-evoked auditory brainstem responses (ABR) were recorded over a wide range of stimulus repetition rates (24/s to 72/s). In experiment 2, auditory steady-state responses were recorded for the same stimulus repetition rates, using three different stimulus types: an amplitude modulated 1-kHz tone (AM), a 1-kHz tone-burst (TB) and a flat-spectrum chirp.

RESULTS

Experiment 1 demonstrates the merging of the typical ABR wave complexes at higher repetition rates, forming a steady-state response. This effect can only be observed if the time window is extended far beyond the window traditionally used for clinical ABR recordings. Experiment 2 reveals similar ASSR amplitude spectra regardless of the stimulus type and repetition rate used.

CONCLUSION

Steady-state responses can be evoked for a large variety of stimulus types and repetition rates. Thus, from a clinician's point of view, steady-state responses cannot be considered a new type of evoked responses. They differ from transient responses primarily in the frequency response method and the longer timeframe required.

Poor adherence to antibiotic prescribing guidelines in acute otitis media--obstacles, implications, and possible solutions

Many countries now have guidelines on the clinical management of acute otitis media. In almost all, the public health goal of containing acquired resistance in bacteria through reduced antibiotic prescribing is the main aim and basis for recommendations. Despite some partial short-term successes, clinical activity databases and opinion surveys suggest that such restrictive guidelines are not followed closely, so this aim is not achieved. Radical new solutions are needed to tackle irrationalities in healthcare systems which set the short-term physician-patient relationship against long-term public health. Resolving this opposition will require comprehensive policy appraisal and co-ordinated actions at many levels, not just dissemination of evidence and promotion of guidelines. The inappropriate clinical rationales that underpin non-compliance with guidelines can be questioned by evidence, but also need specific developments promoting alternative solutions, within a framework of whole-system thinking. Promising developments would be (a) physician training modules on age-appropriate analgesia and on detection plus referral of rare complications like mastoiditis, and (b) vaccination against the most common and serious bacterial pathogens.

Parent versus professional views of the developmental impact of a multi-faceted condition at school age: otitis media with effusion ('glue ear')

BACKGROUND

Several aspects of children's health and development are known from empirical studies to be associated with otitis media with effusion (OME; 'glue ear'). The 'diffuse image' has been an obstacle to defining a core set of impacts about which inter-profession and parent-professional communication can be effective.

AIMS

The study quantifies similarities and differences in how the signs, symptoms, and developmental impact of OME are attributed and construed, between teachers, parents, and ear, nose, and throat (ENT)surgeons.

SAMPLE

Convenience samples were achieved of 118 teachers and 154 parents of affected children; 178 ENT surgeons from a professional sampling frame (association membership) responded.

METHOD

Questionnaires elicited the perceived frequency and concern-value of over 30 manifestations of OME--the various signs, symptoms, and behaviours suggested by the literature. Factor scores derived on the combined sample were compared between respondent groups.

RESULTS

Teachers assign high importance to education and language problems but, relative to parents, they accord lower importance to continuing hearing problems. Teachers and parents weighted behaviour and balance problems similarly, placing behaviour higher, but balance lower, than the ENT specialists did.

CONCLUSIONS

(1) A four-factor reduction of simple questionnaire items well defines the domains of impact of OME, and can express the ways in which views of impact differ between teachers, ENT specialists and parents.(2) Considerable differences of perspective exist between the groups examined. (3) In valuing a set of measured outcomes on actual children, or for other policy research, sets of weights are now available to represent the differing perspectives of parents and professionals (e.g. in testing robustness of a conclusion across differing stakeholder perspectives). (4) The research and development need in respect of teachers' involvement with OME could profitably play to existing strengths. This implies the systematic and structured acquisition and evaluation of teacher-provided impact information.

Cost-Effectiveness Considerations in Otitis Media Treatment

The costs of treatment of children with otitis media with effusion comprise a substantial part of the total health care expenditure. However, there is little information about the value of therapy expressed in cost-effectiveness terms, and disagreement still exists about optimal therapy. This article considers the elements of cost-effectiveness analysis as they pertain to treatment of young children with otitis media with effusion and develops a first approximation model using data from several sources. The assumptions on which this model is based need to be validated by additional research. Otitis media with effusion treatment costs are high because of the large, and apparently increasing, number of symptomatic cases. Medical therapy, which is the primary treatment modality, consumes two thirds of the expenditures for otitis media with effusion. Surgical therapy is a cost-effective treatment for children in whom medical therapy for otitis media with effusion fails. Medical and surgical therapy are complementary, and each should be included in the analysis of cost-effectiveness.

Frequency-specific brainstem responses to bone-conducted tone pulses masked by notched noise

As in the case of auditory brainstem responses (ABRs) to air-conducted stimuli, recording of frequency-specific ABRs to bone-conducted stimuli needs adequate masking of those parts of the basilar membrane that are not to contribute to the ABR. The present study shows that tone-pulse stimulation with notched noise-masking can be realized via a bone vibrator after its frequency response has been flattened. The latency-intensity curves for 4, 2, 1, and 0.5 kHz run approximately parallel, indicating the ABR to be indeed frequency-specific. As adequate air-conducted masking of the nontest ear can produce cross-masking, the use of an insert earphone is proposed. Because of its higher interaural attenuation, a higher masking level can be applied to the nontest ear.

Binaural hearing in adults with histories of otitis media in childhood

There is evidence that children with recent histories of otitis media (OM) have poorer binaural hearing than children with no such histories. In order to investigate whether these deficits persist into adulthood, young adults were selected for auditory testing on the basis of responses to a questionnaire on childhood OM. Binaural performance measures were obtained for the binaural masking level difference, binaural loudness summation and lateralisation of binaural clicks. Although subjects with OM histories reported more auditory disabilities in adulthood, there were no significant differences in binaural performance between OM history subjects and controls. It is suggested that binaural deficits resulting from OM do not usually persist into adulthood.