[Hyperacusis: a mini review].

Hyperacusis refers to the experience of the sound environment being perceived as overwhelmingly loud or painful, and this can severely affect the patient's quality of life. In China little attention has been paid to hyperacusis, and there has been little research undertaken on the topic. Therefore, this article summarizes the recent research on hyperacusis regarding definition, epidemiology, etiology, mechanism, evaluation and treatment to give directions for future research.

An audit of UK audiological practice in specialist paediatric oncology centres regarding hearing assessment of children at risk of ototoxicity due to chemotherapy.

OBJECTIVE: Platinum-based chemotherapy drugs are associated with substantial ototoxicity. The hearing of children treated with these drugs should be closely monitored. METHOD: A questionnaire was sent out to the 19 audiology departments associated with national paediatric cancer specialist centres in the UK looking at current practice in ototoxicity monitoring. RESULTS: Responses were received from 17 of 19 centres (89 per cent). All offered some form of audiometric monitoring service. Extended high-frequency testing (9-20 kHz) was only utilised by 7 services (29 per cent). A majority of respondents were reluctant to consider self-test devices in paediatric ototoxicity monitoring (n = 9; 53 per cent). Provision of long-term audiological follow up is sporadic with only 4 (23 per cent) respondents keeping all children with normal hearing under review once treatment is completed. CONCLUSION: While some good practice in paediatric ototoxicity was identified, opportunities exist to improve clinical practice and protocols, promote multidisciplinary team working and to utilise technologies such as extended high frequency and self-test audiometry.

Positive experiences related to living with tinnitus: A cross-sectional survey.

OBJECTIVE: The aim of this study was to gain insights related to positive experiences reported by adults with tinnitus living in the United Kingdom. DESIGN: A cross-sectional survey design was used in a sample of adults with tinnitus who were interested in undertaking an Internet-based intervention for tinnitus. SETTING: The study was UK wide and data collection was online. PARTICIPANTS: Participants consisted of 240 adults (137 males, 103 females), with an average age of 48.16 years and average tinnitus duration of 11.52 years (SD: 11.88). MAIN OUTCOME MEASURES: Tinnitus severity was measured by means of the Tinnitus Functional Index. To evaluate the secondary effects of tinnitus, the Insomnia Severity Index, the Hearing Handicap Inventory for Adults-Screening Version and the Cognitive Failures Questionnaires were administered. Positive experiences related to tinnitus were explored using an open-ended question format. RESULTS: Around a third of participants (32.5%) reported positive experiences associated with tinnitus. The number of positive responses ranged from one to eight responses per participant, although there were fewer participants with more than one positive response. The predominant themes concerned for (i) coping; (ii) personal development; (iii) support, and to a lesser extent (iv) outlook. Younger participants, those with a lower hearing disability and those with fewer cognitive failures were more likely to report positive experiences associated with having tinnitus. CONCLUSIONS: This study has identified that personal development and a positive outlook are possible despite experiencing tinnitus. Ways to facilitate positive experiences related to tinnitus should be promoted, as these may reduce the negative consequences associated with tinnitus. The most prevalent positive theme was the ability to cope with tinnitus. Positive experiences were also drawn from having clinical and other support networks. This highlights the importance of providing tinnitus interventions that can assist people in coping with tinnitus, particularly to those less likely to relate tinnitus to any positive experiences. Those most likely to be helped include those who are older with greater cognitive difficulties and a greater hearing disability.

Bone-anchored hearing aids for people with bilateral hearing impairment: a systematic review.

BACKGROUND: Bone-anchored hearing aids (BAHAs) are indicated for people with conductive or mixed hearing loss who can benefit from amplification of sound. In resource limited health care systems, it is important that evidence regarding the benefit of BAHAs is critically appraised to aid decision-making. OBJECTIVE OF REVIEW: To assess the clinical effectiveness of BAHAs for people with bilateral hearing impairment. TYPE OF REVIEW: Systematic review. SEARCH STRATEGY: Nineteen electronic resources were searched from inception to November 2009. Additional studies were sought from reference lists, clinical experts and BAHA manufacturers. EVALUATION METHOD: Inclusion criteria were applied by two reviewers independently. Data extraction and quality assessment of full papers were undertaken by one reviewer and checked by a second. Studies were synthesised through narrative review with tabulation of results. RESULTS: Twelve studies were included. Studies suggested audiological benefits of BAHAs when compared with bone-conduction hearing aids or no aiding. A mixed pattern of results was seen when BAHAs were compared to air-conduction hearing aids. Improvements in quality of life with BAHAs were found by a hearing-specific instrument but not generic quality of life measures. Issues such as improvement of discharging ears and length of time the aid can be worn were not adequately addressed by the studies. Studies demonstrated some benefits of bilateral BAHAs. Adverse events data were limited. The quality of the studies was low. CONCLUSIONS: The available evidence is weak. As such, caution is indicated in the interpretation of presently available data. However, based on the available evidence, BAHAs appear to be a reasonable treatment option for people with bilateral conductive or mixed hearing loss. Further research into the benefits of BAHAs, including quality of life, is required to reduce the uncertainty.

Bone-anchored hearing aids (BAHAs) for people who are bilaterally deaf: a systematic review and economic evaluation.

BACKGROUND: A bone-anchored hearing aid (BAHA) consists of a permanent titanium fixture, which is surgically implanted into the skull bone behind the ear, and a small detachable sound processor that clips onto the fixture. BAHAs are suitable for people with conductive or mixed hearing loss who cannot benefit fully from conventional hearing aids. OBJECTIVES: To assess the clinical effectiveness and cost-effectiveness of BAHAs for people who are bilaterally deaf. DATA SOURCES: Nineteen electronic resources, including MEDLINE, EMBASE and The Cochrane Library (inception to November 2009). Additional studies were sought from reference lists and clinical experts. REVIEW METHODS: Inclusion criteria were applied by two reviewers independently. Data extraction and quality assessment were undertaken by one reviewer and checked by a second. Prospective studies of adults or children with bilateral hearing loss were eligible. Comparisons were BAHAs versus conventional hearing aids [air conduction hearing aid (ACHA) or bone conduction hearing aid (BCHA)], unaided hearing and ear surgery; and unilateral versus bilateral BAHAs. Outcomes included hearing measures, validated measures of quality of life (QoL), adverse events and measures of cost-effectiveness. For the review of cost-effectiveness, full economic evaluations were eligible. RESULTS: Twelve studies were included (seven cohort pre-post studies and five cross-sectional 'audiological comparison' studies). No prospective studies comparing BAHAs with ear surgery were identified. Overall quality was rated as weak for all included studies and meta-analysis was not possible due to differences in outcome measures and patient populations. There appeared to be some audiological benefits of BAHAs compared with BCHAs and improvements in speech understanding in noise compared with ACHAs; however, ACHAs may produce better audiological results for other outcomes. The limited evidence reduces certainty. Hearing is improved with BAHAs compared with unaided hearing. Improvements in QoL with BAHAs were identified by a hearing-specific instrument but not generic QoL measures. Studies comparing unilateral with bilateral BAHAs suggested benefits of bilateral BAHAs in many, but not all, situations. Prospective case series reported between 6.1% and 19.4% loss of implants. Most participants experienced no or minor skin reactions. A decision analytic model was developed. Costs and benefits of unilateral BAHAs were estimated over a 10-year time horizon, applying discount rates of 3.5%. The incremental cost per user receiving BAHA, compared with BCHA, was £ 16,409 for children and £ 13,449 for adults. In an exploratory analysis the incremental cost per quality-adjusted life-year (QALY) gained was between £ 55,642 and £ 119,367 for children and between £ 46,628 and £ 100,029 for adults for BAHAs compared with BCHA, depending on the assumed QoL gain and proportion of each modelled cohort using their hearing aid for ≥ 8 or more hours per day. Deterministic sensitivity analysis suggested that the results were highly sensitive to the assumed proportion of people using BCHA for ≥ 8 hours per day, with very high incremental cost-effectiveness ratio values (£ 500,000-1,200,000 per QALY gained) associated with a high proportion of people using BCHA. More acceptable values (£ 15,000-37,000 per QALY gained) were associated with a low proportion of people using BCHA for ≥ 8 hours per day (compared with BAHA). LIMITATIONS: The economic evaluation presented in this report is severely limited by a lack of robust evidence on the outcome of hearing aid provision. This has lead to a more restricted analysis than was originally anticipated (limited to a comparison of BAHA and BCHA). In the absence of useable QoL data, the cost-effectiveness analysis is based on potential utility gains from hearing, that been inferred using a QoL instrument rather than measures reported by hearing aid users themselves. As a result the analysis is regarded as exploratory and the reported results should be interpreted with caution. CONCLUSIONS: Exploratory cost-effectiveness analysis suggests that BAHAs are unlikely to be a cost-effective option where the benefits (in terms of hearing gain and probability of using of alternative aids) are similar for BAHAs and their comparators. The greater the benefit from aided hearing and the greater the difference in the proportion of people using the hearing aid for ≥ 8 hours per day, the more likely BAHAs are to be a cost-effective option. The inclusion of other dimensions of QoL may also increase the likelihood of BAHAs being a cost-effective option. A national audit of BAHAs is needed to provide clarity on the many areas of uncertainty surrounding BAHAs. Further research into the non-audiological benefits of BAHAs, including QoL, is required.

Is musical hallucination an otological phenomenon? a review of the literature.

BACKGROUND: Musical hallucination is the subjective experience of hearing music, or aspects of music, when none is being played, and as such is a disorder of the processing of complex sounds. OBJECTIVE OF REVIEW: To determine the extent to which the otological system is responsible for musical hallucination, and to evaluate approaches to clinical management. TYPE OF REVIEW: A review of all studies and literature reviews pertaining to musical hallucination, supplemented by inclusion of informative case reports. SEARCH STRATEGY: A systematic search of multiple databases carried out on 22nd March 2009 was complemented by referral to the reference lists of included manuscripts. RESULTS: Although not always troublesome in itself, musical hallucination can be a marker of underlying pathology in the ear or brain, or indicate obsessive-compulsive traits or social isolation, and is likely to be clinically underreported. Associations have been reported with hearing loss, female gender, social isolation and being over 60 years of age, although it is rare even in this group, and these may well not be independent risk factors. Robust comparative analysis of these factors with controls has yet to be undertaken. Underlying causes include neurovascular pathology, psychiatric disorders and opioid medications, however these are absent in the majority of cases. CONCLUSIONS: This review supports the proposal that the otological system plays a role in the pathogenesis of musical hallucination. Hearing impairment may act as an initiating factor, and the primary dysfunction is overactivity of auditory association cortex, although an impairment of higher-level inhibition does also seem necessary. Once underlying sinister causes have been excluded, first line treatment should be explanation of the condition and optimisation of hearing. Medications have a role only in selected patient groups.

The effect of auditory stimulation on the tensor tympani in patients following stapedectomy.

CONCLUSION: We believe that a tensor tympani reflex, in response to loud sound, is present in a minority of people, although its functional significance with regard to sound transmission is questionable. The absence of startle response in our stapedectomized subjects makes us question whether the tensor component of the startle response is large enough to be identified by manometry. OBJECTIVES: This study was organized to examine reflex activity to stimulation by loud sound or by startle in the tensor tympani. Although many previous studies have been carried out, results have been contradictory, and methodological flaws have rendered the interpretations questionable. PATIENTS AND METHODS: Stapedectomized patients were invited to take part in the study. Thirteen patients underwent testing by extratympanic manometry, using a standard tympanometer. Responses were observed during repeated stimuli with loud sound at 500, 1000, 2000 and 4000 Hz to the ipsilateral and contralateral ears, and with an air jet against the closed eye. A control group was also studied for the startle test. RESULTS: Three clear ipsilateral (23%) and two clear contralateral (14%) responses to auditory stimuli were seen in the 13 patients. We found responses to startle stimuli in none of our study group and eight (42%) of control ears.

Management of tinnitus induced by brainstem and cerebellar infarction associated with complications of cerebello-pontine angle surgery.

Following surgery in the USA in 1992 to remove a large right cerebello-pontine angle tumour, a 39-year-old woman developed severe brainstem and cerebellar infarction. This left her with severe visual impairment and ataxia. She became able to communicate by means of an adapted finger-spelling alphabet. She had total hearing loss in the right ear and a mild to moderately severe sensorineural hearing loss in the left ear, and severe tinnitus heard throughout the head. Additionally, she experienced hypersensitivity to sound above normal conversational levels, which evoked a synaesthetic feeling of coldness across her upper torso. Previous linear analogue hearing aid fitting had not been beneficial for either hearing or tinnitus. Careful fitting of a digital hearing aid, together with tinnitus counselling, inhibited the patient's tinnitus to 25 per cent of its former intensity after a six month acclimatisation period, and improved communication.

Reproducibility of volume measurements of vestibular schwannomas - a preliminary study.

OBJECTIVE: A preliminary study to investigate the intra-observer and inter-observer variability of measurements of vestibular schwannoma volume using an area-tracing and linear dimension measurement method. DESIGN: Prospective blinded measurements by two observers (one a consultant and one a sub-specialty trainee in neuroradiology). SETTING: Ambulatory patients with known vestibular schwannoma attending a tertiary referral centre. PARTICIPANTS: Twenty-three patients with 26 vestibular schwannomas aged 29-80 years old. MAIN OUTCOME MEASURE: Quantification of the variability in measured volume due to intra- and inter-observer measurement differences, expressed as reliability coefficients within which 95% of repeated measurements are calculated to lie from each other in relative percentage terms. RESULTS: For the linear measurement method, intraobserver variability was calculated to have a reliability coefficient of 65% and for interobserver variability this was 155%. For the area tracing method, the corresponding coefficients were 26% for intraobserver variability and 44% for interobserver variability. CONCLUSIONS: Volume measurements in vestibular schwannoma are variable even when the measurements are made by the same observer on identical images. The area tracing method, commonly regarded as the gold standard, is less variable than a linear method but still introduces more variability than commonly realized (for 95% of patients, repeated measurements by the same observer lie within around 25% of each other). Manual area tracing is not widely used in practice because it is time consuming and reliable automated methods are eagerly awaited.

The evidence base for the application of contralateral bone anchored hearing aids in acquired unilateral sensorineural hearing loss in adults.

. Acquired unilateral sensorineural hearing loss reduces the ability to localize sounds and to discriminate in background noise. . Four controlled trials attempt to determine the benefit of contralateral bone anchored hearing aids over contralateral routing of signal (CROS) hearing aids and over the unaided condition. All found no significant improvement in auditory localization with either aid. Speech discrimination in noise and subjective questionnaire measures of auditory abilities showed an advantage for bone anchored hearing aid (BAHA) > CROS > unaided conditions. . All four studies have material shortfalls: (i) the BAHA was always trialled after the CROS aid; (ii) CROS aids were only trialled for 4 weeks; (iii) none used any measure of hearing handicap when selecting subjects; (iv) two studies have a bias in terms of patient selection; (v) all studies were underpowered (vi) double reporting of patients occurred. . There is a paucity of evidence to support the efficacy of BAHA in the treatment of acquired unilateral sensorineural hearing loss. Clinicians should proceed with caution and perhaps await a larger randomized trial. . It is perhaps only appropriate to insert a BAHA peg at the time of vestibular schwanoma tumour excision in patients with good preoperative hearing, as their hearing handicap increases most.

Team working to improve outcome in vestibular schwannoma surgery.

The concept of the 'learning curve' in the early years of consultant appointment is no longer acceptable and yet, for most complex operations, learning is a career-long process. Sub-specialization offers part of the solution to this problem by concentrating expertise, but there remains the question of how to introduce new team members without adversely affecting patient outcome. Shortened training and an increasingly aware public, who are more questioning of the experience and outcomes of those treating them, has required the surgical profession to move away from individual consultant practice and embrace team-working. When, in 1997, a second neurosurgeon joined the skull base team at Addenbrooke's Hospital, his introduction to acoustic neuroma surgery was mentored and operative cases were carefully selected at first. In this article, we discuss our experience with consultant mentoring, and compare the results of the first 100 translabyrinthine acoustic neuroma operations performed under this system with the first cohort of a similar number of patients published from Cambridge in 1989.

The effect of mental alerting on gaze-evoked nystagmus.

OBJECTIVES: To determine whether mental alerting (MA) makes a significant difference to nystagmus recorded during gaze testing using electronystagmography (ENG). DESIGN: A prospective study, blinded interpretation of test results, alternate order of testing sequence. SETTING: Vestibular assessment clinic in a tertiary referral centre. PARTICIPANTS: A total of 80 patients were seen by the authors (R.L.H., K.F.L.M.) for vestibular assessment, between August 2002 and February 2004. Patients cognitively unable to perform MA tasks or with limited English were omitted. Patients all underwent gaze-testing using ENG. Each patient was tested twice, once without MA and once with an MA task, in an alternate test order. MAIN OUTCOME MEASURES: Slow-phase velocity values of recorded nystagmus, number of patients with clinically significant nystagmus (slow-phase velocity > or = 6 deg/s). RESULTS: A total of eight patients had significant gaze-evoked nystagmus when tested without MA and a total of six patients when tested with MA. Only four of these patients were common to both groups. When all nystagmus values (regardless of significance) were considered, no statistically significant differences between nystagmus measured with and without alerting were found (Wilcoxon signed rank test, P > 0.05). CONCLUSIONS: Mental alerting during gaze testing did not result in a significant difference in nystagmus and is just as likely to result in an exacerbation as a reduction in slow-phase velocity. In addition, MA is likely to result in a noisy (and therefore difficult to interpret) recording and increases the impact of the test on the patient. In view of these findings, we propose that MA is contraindicated during the gaze-testing component of the vestibular test battery.

Change in auditory attention in a child with a cochlear implant, with ADHD treated with methylphenidate (Ritalin): a case study.

This retrospective single case study describes the effect of methylphenidate (Ritalin) on the auditory attention of an implanted child with attention deficit and hyperactivity disorder (ADHD). Child A received a Nucleus 22 cochlear implant at age 4 years 6 months. His behaviour before and after the implant surgery was challenging. Language development made little progress. Five years later a diagnosis of ADHD was made and methylphenidate (Ritalin) was prescribed. The apparent effect of this drug on auditory attention is discussed. In this study, methylphenidate did not appear to affect threshold levels or responses in tuning. However, audition did improve in everyday listening conditions. The drug did not appear to assist language development. Copyright (c) 2005 John Wiley & Sons, Ltd.

Referral patterns in vestibular schwannomas --10 years on.

Diagnostic imaging techniques, symptom awareness and education of local sources of referral in vestibular schwannomas, including general practitioners, have all improved in the last 10 years. The referral patterns in vestibular schwannomas in Cambridgeshire in the period 1981-1993 has been reported.(1) A direct comparison was made with regard to referral patterns seen in the last 10 years paying particular emphasis to source of referral, diagnosis at referral and symptoms/size at presentation. The incidence of vestibular schwannomas in the region is compared and discussed. Patients' managed by the 'watch and wait' policy were particularly scrutinized, as they were not discussed previously. Retrospective analysis of computerized database was used. We have demonstrated an increase in the proportion of referrals with known vestibular schwannoma to 90% of all referrals. No significant change in length of history prior to referral, source of referral or principal presenting symptom were found. An overall decrease in tumour size was found but an increase in the percentage with larger tumours (>4.5 cm). We attribute the significant findings to an increase in availability of magnetic resonance (MR) scanners in the country during the past 10 years. It appears that some tumours would still present with no symptoms until late and therefore will elude identification until large in spite of a low threshold for MR scanning.

Head-shaking nystagmus in patients with a vestibular schwannoma.

The aim of this study was to calculate the sensitivity of the head-shake test for peripheral and central vestibular dysfunction associated with unilateral sporadic vestibular schwannoma and to discuss the feasibility of using the head-shake test as a screening test. The study group consisted of 102 patients with unilateral sporadic vestibular schwannomas, who were seen consecutively for preoperative vestibular assessment, including the head-shake test. The sensitivity of the head-shake test for vestibular schwannoma was found to be 22%, and the sensitivity and specificity of the head-shake test for canal paresis (>/=25%) were found to be 27% and 88%, respectively. Patients with abnormalities in the central vestibular system and with a greater canal paresis were more likely to have head-shake nystagmus, although, even for severe canal paresis, the sensitivity of the test remained low at 36%. The direction of nystagmus was found to be contra-lateral to the side of the tumour in 86% of patients. It was concluded that the head-shake test is of insufficient sensitivity to be used as a screening test either for vestibular schwannoma or for vestibular-system abnormalities associated with vestibular schwannoma. The deduction is made that the head-shake test is of insufficient sensitivity or specificity to be of clinical value as a screening test for vestibular dysfunction in a general population with symptoms of imbalance.