Hearing aids for the treatment of tinnitus

The effect of cochlear implantation on tinnitus in patients with post lingual bilateral profound hearing loss

INTRODUCTION

In this study we investigated the effect of cochlear implantation on tinnitus in patients with post lingual bilateral profound hearing loss.

METHODS

In this retrospective study, 66 post-lingual deaf patients over 18 years old who referred for cochlear implantation and complained of tinnitus were included. Patients were divided into two groups with residual hearing (in frequency 250-500 Hz) and without residual hearing. All data including age, gender, type of implants, type of surgery, cause of the disease, and information on the THI score before cochlear implantation, one month after cochlear implantation and one year after cochlear implantation was recorded and analyzed.

RESULTS

Nine patients had residual hearing, while 57 patients did not. After one month and one year, in both groups, the mean THI score has decreased significantly (p-value = 0.001), but there was no significant difference in the mean THI score before surgery and one month and one year after surgery between two groups with and without residual hearing. There was no significant difference in tinnitus severity according to THI-grade between two groups. Also there was no significant difference in THI score and the cause of the hearing loss, type and insertion method of implantation, one month and one year after the surgery between two groups.

CONCLUSION

According to our results, the was no significant correlation between residual hearing and tinnitus score before surgery, one month and one year after the surgery.

History of Tinnitus Research at the VA National Center for Rehabilitative Auditory Research (NCRAR), 1997-2021: Studies and Key Findings

The Veterans Affairs (VA) Rehabilitation Research & Development (RR&D) National Center for Rehabilitative Auditory Research (NCRAR) was first funded by the RR&D Service in 1997 and has been funded continuously since that time. The overall purpose of the NCRAR is to "improve the quality of life of Veterans and others with hearing and balance problems through clinical research, technology development, and education that leads to better patient care" ( www.ncrar.research.va.gov ). An important component of the research conducted at the NCRAR has been a focus on clinical and rehabilitative aspects of tinnitus. Multiple investigators have received grants to conduct tinnitus research and the present article provides an overview of this research from the NCRAR's inception through 2021.

Should Tinnitus Patients with Subclinical Hearing Impairment Be Offered Hearing Aids? A Comparison of Tinnitus Mitigation Following 3 Months Hearing Aid Use in Individuals with and without Clinical Hearing Impairment

There is a consensus among tinnitus experts to not recommend hearing aids for tinnitus patients with subclinical hearing impairment. However, this notion is arbitrary, as no previous study has compared the treatment effect of hearing aids on tinnitus distress in patients with and without clinical hearing impairment. In this article, we investigate whether tinnitus patients with clinical and subclinical hearing impairment differ in terms of tinnitus mitigation after hearing aid fitting. Twenty-seven tinnitus patients with either clinical (n = 13) or subclinical (n = 14) hearing impairment were fitted with hearing aids. All participants filled out the tinnitus functional index (TFI) before hearing aid fitting and after 3 months of hearing aid use. Clinically meaningful reductions in tinnitus distress (-13 TFI points or more) were seen in both groups, and the difference in tinnitus mitigation between tinnitus patients with clinical (mean TFI reduction = 17.0 points) and subclinical hearing impairment (mean TFI reduction = 16.9 points) was not statistically significant (p = 0.991). Group differences on the suspected confounding factors of age, sex, time since tinnitus debut, tinnitus distress (TFI score) at baseline, and treatment adherence were statistically insignificant. In light of this, we argue that clinical hearing impairment is not required to achieve meaningful tinnitus mitigation with hearing aids, and that hearing aids could be recommended for tinnitus patients with subclinical hearing impairment.

Hearing Aids Combined With Educational Counseling Versus Educational Counseling Alone for Tinnitus Treatment in Patients With Hearing Loss: A Longitudinal Follow-Up Study

PURPOSE

The effect of hearing aids (HAs) and educational counseling (EC) or their combination on tinnitus is ambiguous. This study aimed to investigate whether the combined use of HAs and EC is more effective than EC alone on tinnitus relief.

METHOD

A total of 72 adults with chronic, bothersome tinnitus and coexisting sensorineural hearing loss completed at least 1-month and 3-month follow-up. After receiving EC and HA prescriptions, 21 participants selected to purchase HAs (i.e., the HA + EC group), whereas the remaining 51 refused to use HAs despite recommendations (i.e., the EC group). Tinnitus severity was measured by Tinnitus Handicap Inventory (THI), Tinnitus Evaluation Questionnaire (TEQ), and Visual Analog Scale (VAS) for loudness. The primary outcome measure was THI, and tinnitus relief was defined as a 20-point or more reduction in THI. A generalized linear mixed model was used to confirm that the heterogeneity in baseline characteristics between groups did not interfere with the results.

RESULTS

The THI, TEQ, and VAS scores decreased significantly after treatments, and both groups yielded a similar trend of reduction. There were no significant differences in the incidence of tinnitus relief and time-to-event curves between the two groups. In addition, the length of follow-up did not affect treatment effectiveness.

CONCLUSION

There was insufficient evidence to support the superiority of the combined use of HA and EC for tinnitus over EC with no device.

Evaluation and Management of Tinnitus: Are There Opportunities for Improvement?

OBJECTIVE

To review current information about diagnosis and management of tinnitus aiming to identify opportunities for achieving a cost-effective, efficient, evidence-based approach that meets the needs of tinnitus sufferers.

DATA SOURCES

PubMed/MEDLINE.

REVIEW METHODS

In total, 249 relevant published reports were reviewed. Pertinent keywords and MeSH terms identified reports via PubMed and EMBASE. Acknowledged experts were consulted on ways to improve tinnitus management.

CONCLUSIONS

There may be opportunities to improve evaluation and management of patients with tinnitus using modern modes of communication and a multidisciplinary therapeutic approach.

IMPLICATIONS FOR PRACTICE

Tinnitus can adversely affect quality of life while being time-consuming and costly to evaluate and manage. Based on both personal experience and the reports of others, patients with tinnitus who choose to see a physician primarily want to know two things: (1) that the tinnitus that is so distressing will not remain at the same level of severity forever and (2) that something can be done to help cope with the tinnitus that is so annoying. Recent advancements in internet communications, social media, information technology, artificial intelligence, machine learning, holistic medical care, mind-body integrative health care, and multidisciplinary approaches in medical therapeutics may be possibly making new ways of meeting the needs of patients with tinnitus.

Hearing Aids Mitigate Tinnitus, But Does It Matter if the Patient Receives Amplification in Accordance With Their Hearing Impairment or Not? A Meta-Analysis

PURPOSE

The purpose of the present meta-analysis is to explore the potential effects of objective verification of hearing aid amplification on tinnitus-related outcomes.

METHOD

Twenty-seven studies reporting tinnitus outcomes pre and post hearing aid fitting were identified through a systematic literature search. From these studies, data from 1,400 participants were included in the present meta-analysis. Studies were divided into subgroups based on whether they had reported performing objective verification of the participants' hearing aid amplification or not. Outcome measures were tinnitus distress and tinnitus loudness.

RESULTS

Meta-analyses of all included studies indicated verified amplification to result in significantly enhanced reduction of tinnitus loudness (p < .00001), while the enhanced reduction of tinnitus distress only approached statistical significance (p = .07). However, when excluding an outlier from the subgroup of studies using unverified amplification, individuals receiving verified amplification showed significantly greater reduction of tinnitus distress (p = .02). In addition, analyses of longitudinal effects revealed that the reductions of tinnitus distress decreased over time among individuals receiving unverified amplification but increased over time among individuals receiving verified amplification.

CONCLUSIONS

The present meta-analysis indicates verified hearing aid amplification to be superior to unverified amplification in terms of reduction of tinnitus loudness and distress. The longitudinal increase of mitigation of tinnitus distress with verified amplification only may reflect improved neural reorganization and/or better adherence to hearing aid use, with verified compared to unverified amplification. Due to the low cost of hearing aid verification compared to the high societal cost of tinnitus, objective verification of hearing aid amplification for tinnitus patients is recommended.

Broadband Amplification as Tinnitus Treatment

This study investigated the effect of broadband amplification (125 Hz to 10 kHz) as tinnitus treatment for participants with high-frequency hearing loss and compared these effects with an active placebo condition using band-limited amplification (125 Hz to 3–4 kHz). A double-blinded crossover study. Twenty-three participants with high-frequency (≥3 kHz) hearing loss and chronic tinnitus were included in the study, and 17 completed the full treatment protocol. Two different hearing aid treatments were provided for 3 months each: Broadband amplification provided gain in the frequency range from 125 Hz to 10 kHz and band-limited amplification only provided gain in the low-frequency range (≤3–4 kHz). The effect of the two treatments on tinnitus distress was evaluated with the Tinnitus Handicap Inventory (THI) and the Tinnitus Functional Index (TFI) questionnaires. The effect of the treatment on tinnitus loudness was evaluated with a visual analog scale (VAS) for loudness and a psychoacoustic loudness measure. Furthermore, the tinnitus annoyance was evaluated with a VAS for annoyance. The tinnitus pitch was evaluated based on the tinnitus likeness spectrum. A statistically significant difference was found between the two treatment groups (broadband vs. band-limited amplification) for the treatment-related change in THI and TFI with respect to the baseline. Furthermore, a statistically significant difference was found between the two treatment conditions for the annoyance measure. Regarding the loudness measure, no statistically significant differences were found between the treatments, although there was a trend towards a lower VAS-based loudness measure resulting from the broadband amplification. No changes were observed in the tinnitus pitch between the different conditions. Overall, the results from the present study suggest that tinnitus patients with high-frequency hearing loss can experience a decrease in tinnitus-related distress and annoyance from high-frequency amplification.

Spectrally Matched Near-Threshold Noise for Subjective Tinnitus Loudness Attenuation Based on Stochastic Resonance

Recently, we proposed a model of tinnitus development based on a physiological mechanism of permanent optimization of information transfer from the auditory periphery to the central nervous system by means of neuronal stochastic resonance utilizing neuronal noise to be added to the cochlear input, thereby improving hearing thresholds. In this view, tinnitus is a byproduct of this added neuronal activity. Interestingly, in healthy subjects auditory thresholds can also be improved by adding external, near-threshold acoustic noise. Based on these two findings and a pilot study we hypostatized that tinnitus loudness (TL) might be reduced, if the internally generated neuronal noise is substituted by externally provided individually adapted acoustic noise. In the present study, we extended the data base of the first pilot and further optimized our approach using a more fine-grained adaptation of the presented noise to the patients' audiometric data. We presented different spectrally filtered near-threshold noises (-2 dB to +6 dB HL, 2 dB steps) for 40 s each to 24 patients with tonal tinnitus and a hearing deficit not exceeding 40 dB. After each presentation, the effect of the noise on the perceived TL was obtained by patient's response to a 5-scale question. In 21 out of 24 patients (13 women) TL was successfully subjectively attenuated during acoustic near-threshold stimulation using noise spectrally centered half an octave below the individual's tinnitus pitch (TP). Six patients reported complete subjective silencing of their tinnitus percept during stimulation. Acoustic noise is able to reduce TL, but the TP has to be taken into account. Based on our findings, we speculate about a possible future treatment of tinnitus by near-threshold bandpass filtered acoustic noise stimulation, which could be implemented in hearing aids with noise generators.

Hearing Therapy Improves Tinnitus-Related Distress in Mildly Distressed Patients with Chronic Tinnitus and Mild-to-Moderate Hearing Loss: A Randomized-Controlled Cross-Over Design

BACKGROUND

The psychological effects of hearing aids and auditory training are underinvestigated.

OBJECTIVE

To assess the short- and long-term effects of an industry-developed auditory training on tinnitus-related distress, perceived stress, and psychological epiphenomena in patients with chronic tinnitus and mild-to-moderate hearing loss.

METHOD

One-hundred-seventy-seven gender-stratified patients were randomized to an immediate [IIG] or delayed [DIG] intervention group. Following binaural hearing aid fitting, participants completed a CD-enhanced 14-days self-study program. Applying a randomized-controlled cross-over design, psychological measures were obtained at four times: pre-treatment/wait [IIG: t₁; DIG: wait], post-treatment/pre-treatment [IIG: t₂; DIG: t₁], follow-up/post-treatment [IIG: t₃; DIG: t₂], and follow-up [DIG: t₃]. Between- and within-group analyses investigated treatment-related effects and their stability at a 70-day follow-up.

RESULTS

Overall, distress symptom severity was mild. Unlike the DIG, the IIG showed significant improvements in tinnitus-related distress. Some psychological epiphenomena, notably anxiety, slightly improved in both groups. Within-group analyses demonstrated the stability of the tinnitus-distress-related effects, alongside uncontrolled improvements of perceived stress and mood-related symptoms at follow-up.

CONCLUSIONS

The investigated hearing therapy lastingly improves tinnitus-related distress in mildly distressed patients with chronic tinnitus and mild-to-moderate hearing loss. Beneficial psychological knock-on effects deserve further investigation.

Hearing Aid Effects and Satisfaction in Patients with Tinnitus

This study aimed to evaluate the effectiveness of and satisfaction with hearing aids as a treatment option for tinnitus with hearing loss. Methods: This retrospective study used the tinnitus handicap inventory (THI), the satisfaction with amplification in daily life (SADL) questionnaire, and a medical chart review. A total of 116 patients treated between August 2018 and December 2020 were included. All patients with tinnitus and hearing loss underwent the same counseling sessions. Sixty patients chose to have hearing aids fitted (aided group), whereas 56 patients chose not to (non-aided group). Both the groups had similar audiometric configurations, durations of tinnitus, and ages. Structured interviews were performed, with various measures evaluated using the visual analog scale (VAS) and the THI questionnaire, before and six months after fitting the hearing aids. The SADL questionnaire was administered 6 months after fitting the hearing aids. Results: The patients’ THI scores reduced 6 months after the counseling, but the improvement in the THI scores was only significant in the group that received hearing aids. There were significant differences between the VAS scores of the two groups, and the changes in the VAS scores in the groups were statistically different. Subjective satisfaction with a hearing aid increased with improvements to tinnitus-related discomfort. Conclusion: The study’s results indicated that patients with hearing loss and tinnitus can be treated with hearing aids and counseling.

Subjective tinnitus: lesion-induced pathological central homeostasis remodeling

Subjective tinnitus is the most common type of tinnitus, which is the manifestation of pathological activities in the brain. It happens in a substantial portion of the general population and brings significant burden to the society. Severe subjective tinnitus can lead to depression and insomnia and severely affects patients' quality of life. However, due to poor understanding of its etiology and pathogenesis, treatment of subjective tinnitus remains challenging. In recent decades, a growing number of studies have shown that subjective tinnitus is related to lesion-induced neural plasticity of auditory and non-auditory central systems. This article reviews cellular mechanisms of neural plasticity in subjective tinnitus to provide further understanding of its pathogenesis.

Internet-based cognitive-behavioural therapy for tinnitus: secondary analysis to examine predictors of outcomes

OBJECTIVES

The current study examined predictors of outcomes of internet-based cognitive-behavioural therapy (ICBT) for individuals with tinnitus.

DESIGN

Secondary analysis of intervention studies.

SETTING

Internet-based guided tinnitus intervention provided in the UK.

PARTICIPANTS

228 individuals who underwent ICBT.

INTERVENTIONS

ICBT.

PRIMARY AND SECONDARY OUTCOME MEASURES

The key predictor variables included demographic, tinnitus, hearing-related and treatment-related variables as well as clinical factors (eg, anxiety, depression, insomnia), which can have an impact on the treatment outcome. A 13-point reduction in Tinnitus Functional Index (TFI) scores has been defined as a successful outcome.

RESULTS

Of the 228 subjects who were included in the study, 65% had a successful ICBT outcome. As per the univariate analysis, participants with a master's degree or above had the highest odds of having a larger reduction in tinnitus severity (OR 3.47; 95% CI 1.32 to 12.51), compared with the participants who had education only up to high school or less. Additionally, the baseline tinnitus severity was found to be a significant variable (OR 2.65; 95% CI 1.50 to 4.67) contributing to a successful outcome with the intervention. Both linear and logistic regression models have identified education level and baseline tinnitus severity to be significant predictor variables contributing to a reduction in tinnitus severity post-ICBT. As per the linear regression model, participants who had received disability allowance had shown a 25.3-point lower TFI reduction compared with those who did not experience a decrease in their workload due to tinnitus after adjusting for baseline tinnitus severity and their education level.

CONCLUSIONS

Predictors of intervention outcome can be used as a means of triaging patients to the most suited form of treatment to achieve optimal outcomes and to make healthcare savings. Future studies should consider including a heterogeneous group of participants as well as other predictor variables not included in the current study.ClinicalTrial.gov Registration: NCT02370810 (completed); NCT02665975 (completed).

Evaluation of Outcomes Related to Hearing and Tinnitus After Ossicular Chain Reconstruction

OBJECTIVE

The aim of this study was to evaluate both audiological and tinnitus related results in patients with tinnitus undergoing ossicular chain reconstruction (OCR) for ossicular chain injury.

METHODS

Between January 2015 and January 2019, patients who underwent OCR due to ossicular chain pathology and developed tinnitus symptoms were included in the study group. Middle ear pathologies were standardized using the middle ear risk index (MERI) scoring system and the tinnitus handicap inventory (THI) was used to determine the severity of tinnitus. The surgical methods used for reconstruction were partial ossicular replacement prosthesis (PORP) or total ossicular replacement prosthesis (TORP), depending on the patient's pathology.

RESULTS

The study group consisted of 43 patients aged between 34 and 65 years. Mean MERI score of the patients was 6.42 ± 2.52. When assessed categorically, 18.6% of the study group was identified in the 'mild', 46.5% were in the 'moderate', and 34.5% were in the 'severe' MERI category. Patients in the TORP group and those who were undergoing second session OCR had higher MERI and preop THI scores. Post-operative tinnitus levels were higher in patients who had OCR in the second session and were in the severe risk group. The ABG and tinnitus scores of patients were found to improve with OCR. In patients who underwent TORP, both ABG and tinnitus scores decreased significantly. Whereas, in patients who underwent PORP, only ABG values decreased significantly. After OCR, both ABG value and tinnitus scores significantly decreased compared to pre-operative results. ABG recovery rate was 100% in the study group.

CONCLUSION

It can be said that OCR positively changes both audiological parameters and tinnitus levels in ossicular chain pathologies.

The state of the art of sound therapy for subjective tinnitus in adults

Background:

Sound therapy is a clinically common method of tinnitus management. Various forms of sound therapy have been developed, but there are controversies regarding the selection criteria and the efficacy of different forms of sound therapy in the clinic. Our goal was to review the types and forms of sound therapy and our understanding of how the different characteristics of tinnitus patients influence their curative effects so as to provide a reference for personalized choice of tinnitus sound therapy.

Method:

Using an established methodological framework, a search of six databases including PubMed identified 43 records that met our inclusion criteria. The search strategy used the following key words: tinnitus AND (acoustic OR sound OR music) AND (treatment OR therapy OR management OR intervention OR measure).

Results:

There are various forms of sound therapy, and most of them show positive therapeutic effects. The effect of customized sound therapy is generally better than that of non-customized sound therapy, and patients with more severe initial tinnitus respond better to sound therapy.

Conclusion:

Sound therapy can effectively suppress tinnitus, at least in some patients. However, there is a lack of randomized controlled trials to identify effective management strategies. Further studies are needed to identify the most effective form of sound therapy for individualized therapy, and large, multicenter, long-term follow-up studies are still needed in order to develop more effective and targeted sound-therapy protocols. In addition, it is necessary to analyze the characteristics of individual tinnitus patients and to unify the assessment criteria of tinnitus.

Conventional versus notch filter amplification for the treatment of tinnitus in adults with mild-to-moderate hearing loss

INTRODUCTION

Conventional hearing aids are commonly recommended for the treatment of tinnitus, though results of studies investigating the efficacy of hearing aid-based tinnitus treatments have been mixed. Recently, it has been suggested that the addition of a notch filter around the tinnitus frequency might enhance lateral inhibitory mechanisms and thereby improve tinnitus severity relative to traditional processing. The primary aim of this study was to compare the effects of conventional versus notch filter amplification strategies on subjective tinnitus severity in adults with mild-to-moderate hearing loss and no previous hearing aid experience.

METHODS

Thirty-nine adults (mean age=53.6 years; SD=9.7 years) with bilateral, mild to moderate sensorineural hearing loss and an established clinical history of stable, tonal tinnitus participated in this double-blinded study. Each participant was randomly assigned to complete a 12-week hearing aid trial using either a conventional amplification strategy or a strategy which applied a notch filter at the given participant's tinnitus pitch match frequency. Tinnitus-related handicap and distress were assessed before and after the hearing aid trial via the Tinnitus Handicap Inventory (Newman et al., 1996) and the Tinnitus Questionnaire (Hallam et al., 1988).

RESULTS

Average tinnitus severity did not differ significantly between the conventional and notch filter amplification groups following treatment. Moreover, average pre- to post-intervention change scores were relatively low for both groups, indicating minimal effect of either treatment on tinnitus symptoms. Participant age, high-frequency pure-tone average hearing threshold, average daily hearing aid usage, and pre-intervention tinnitus severity ratings were not predictive of treatment success or failure.

DISCUSSION

Results of the present study suggest no significant effect of either conventional or notch filter amplification on average ratings of tinnitus severity following a 12-week hearing aid trial. However, as clinically meaningful changes in tinnitus severity were identified for some participants, future work is needed to better identify those individuals most likely to benefit, as well as optimal amplification characteristics.

Tinnitus Suppression Effect of Hearing Aids in Patients With High-frequency Hearing Loss: A Randomized Double-blind Controlled Trial

INTRODUCTION

Hearing aids (HAs) with frequency lowering have been used for high-frequency hearing loss (HFHL), but their effects on tinnitus relief have not been studied extensively. This randomized double-blind trial was performed to investigate and compare tinnitus suppression effects of conventional type HAs and frequency-lowering HAs in patients with HFHL.

METHODS

A total of 114 patients were randomized into three groups: conventional HA using wide dynamic range compression, HA with frequency translation, and HA with linear frequency transposition. Participants wore HAs for 3 months and then discontinued their use. The final evaluation was performed at 3 months after cessation of wearing HA (6 mo after the initial visit). The Tinnitus Handicap Inventory (THI) score and additional variables, such as matched tinnitus loudness and visual analog scale scores of subjectively perceived tinnitus loudness, daily awareness, and annoyance, were measured at the initial visit and at 3- and 6-month follow-ups.

RESULTS

THI score and most of the additional outcomes were significantly improved at 3 and 6 months (3 mo after HA removal) compared with their initial values in all three groups. The incidence rates of patients with improvements in the THI score by 20% or more were 71.0, 72.7, and 74.3% at 3 months, and 54.8, 51.6, and 59.4% at 6 months for the three groups, respectively. There were no significant differences in primary or additional variables between hearing aid types at either 3 or 6 months.

CONCLUSION

This is a consolidated standards of reporting trials-guided study providing direct evidence for tinnitus suppression effects of HA alone, without accompanying counseling or any other treatments, which lasted for at least 3 months after patients stopped using HAs. HAs effectively suppressed tinnitus in patients with HFHL regardless of the amplification strategy type.

Pre-treatment Ongoing Cortical Oscillatory Activity Predicts Improvement of Tinnitus After Partial Peripheral Reafferentation With Hearing Aids

Although hearing aids (HAs) are sometimes efficacious in abating tinnitus, the precise mechanism underlying their effect is unclear and predictors of symptom improvement have not been determined. Here, we examined the correlation between the amount of tinnitus improvement and pre-HA quantitative electroencephalography (qEEG) findings to investigate cortical predictors of improvement after wearing HAs. QEEG data of thirty-three patients with debilitating tinnitus were retrospectively correlated with the percentage improvements in tinnitus handicap inventory and the numerical rating scale scores of tinnitus. Activation of brain areas involved in the default mode network (DMN; inferior parietal lobule, parahippocampus, and posterior cingulate cortex) were found to be a negative predictor of improvement in tinnitus-related distress after wearing HAs. In addition, higher pre-HA cortical power at the medial auditory processing system or higher functional connectivity of the lateral/medial auditory pathway to the DMN was found to serve as a positive prognostic indicator with regard to improvement of tinnitus-related distress. In addition, insufficient activity of the pre-treatment noise canceling system tended to be a negative predictor of tinnitus perception improvement after wearing HAs. The current study may serve as a milestone toward a pre-HAs prediction strategy for tinnitus improvements in subjects with hearing loss and severe tinnitus.

Effects of Vibrant Soundbridge on tinnitus accompanied by sensorineural hearing loss

OBJECTIVES

Tinnitus is a common symptom among patients with hearing loss, and many studies have reported successful tinnitus suppression with hearing devices. Active middle ear implantation of the Vibrant Soundbridge (VSB) is a good alternative to existing hearing devices. This study evaluated the effects of VSB implantation on tinnitus and sought to identify the main audiological factor that affects tinnitus suppression.

METHODS

The study participants were 16 adults who had tinnitus with sensorineural hearing loss, and who underwent VSB implantations. Pure-tone audiometry; word recognition test; tinnitus handicap inventory (THI); and visual analog scale (VAS) assessment of loudness, awareness, and annoyance were performed before and 12 months after surgery. Changes in hearing threshold, word recognition scores (WRS), THI scores, and VAS scores were analyzed.

RESULTS

VAS scores for loudness (mean difference: 1.9, 95% CI: 0.6, 3.1), awareness (mean difference: 1.6, 95% CI: 0.4, 2.8), and annoyance (mean difference: 1.7, 95% CI: 0.7, 2.8) showed significant improvements from baseline to 12 months after surgery. In addition, THI scores showed a significant decrease (mean difference: 13.8, 95% CI: 2.9, 24.9). The average hearing threshold level, WRS, and most comfortable level (MCL) also showed significant improvements at 12 months after surgery (mean difference: 17.3, 95% CI: 13.3, 21.3; mean difference: -7.6, 95% CI: -15.1, -0.1; mean difference: 26.3, 95% CI: 22.9, 29.6, respectively). Among the aforementioned factors, changes in MCL were best correlated with those in THI scores (mean difference: 2.55, 95% CI: 0.90, 4.21).

CONCLUSION

A VSB implant is beneficial to subjects with tinnitus accompanied by sensorineural hearing loss. The changes in THI scores best correlated with those in MCL. This improvement may represent a masking effect that contributes to tinnitus suppression in patients with VSB implants.

Unpleasantness of Amplified Environmental Sound Used in Tinnitus Sound Therapy: A Preliminary Study of Clinical Assessment

OBJECTIVES

In this study, our aim was to use environmental sounds amplified in the frequency region corresponding to the tinnitus frequency of individual patients and apply them as sound therapy in tinnitus retraining therapy (TRT). In this pilot study, we 1) investigated the unpleasantness of processed environmental sounds using the amplification, attenuation, and removal in different frequency regions; 2) compared the unpleasantness of processed sounds for older and younger groups of participants; and 3) determined the amplification level appropriate for a clinical test.

MATERIALS AND METHODS

We processed the sound of a river with three types of modification (amplified, attenuated, and notched) at a one-octave width of seven central frequencies, in the range 250-8000 Hz. Amplified and attenuated sounds were processed with five positive gains (+6, +12, +15.6, +18, and +20 dB) and two negative gains (-6 and -12 dB). Twenty-three older participants and 23 younger participants rated the unpleasantness of sounds using a visual analog scale.

RESULTS

We found that, in the older group, there was no difference in unpleasantness among the three modifications. Older participants rated the level of unpleasantness as lower than younger participants for processed sounds in the high-frequency region. There were no marked differences among the amplification levels in the group of older participants.

CONCLUSION

Based on the results, we decided that our clinical study would target older patients who had a tinnitus frequency over 4000 Hz and would compare the effect of an amplified sound with a 20 dB gain at the frequency corresponding to individual tinnitus with notched sound.

Sound therapy (using amplification devices and/or sound generators) for tinnitus

BACKGROUND

Tinnitus affects 10% to 15% of the adult population, with about 20% of these experiencing symptoms that negatively affect quality of life. In England alone there are an estimated ¾ million general practice consultations every year where the primary complaint is tinnitus, equating to a major burden on healthcare services. Clinical management strategies include education and advice, relaxation therapy, tinnitus retraining therapy (TRT), cognitive behavioural therapy (CBT), sound enrichment using ear-level sound generators or hearing aids, and drug therapies to manage co-morbid symptoms such as insomnia, anxiety or depression. Hearing aids, sound generators and combination devices (amplification and sound generation within one device) are a component of many tinnitus management programmes and together with information and advice are a first line of management in audiology departments for someone who has tinnitus.

OBJECTIVES

To assess the effects of sound therapy (using amplification devices and/or sound generators) for tinnitus in adults.

SEARCH METHODS

The Cochrane ENT Information Specialist searched the Cochrane ENT Register; Central Register of Controlled Trials (CENTRAL, via the Cochrane Register of Studies); Ovid MEDLINE; Ovid Embase; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 23 July 2018.

SELECTION CRITERIA

Randomised controlled trials (RCTs) recruiting adults with acute or chronic subjective idiopathic tinnitus. We included studies where the intervention involved hearing aids, sound generators or combination hearing aids and compared them to waiting list control, placebo or education/information only with no device. We also included studies comparing hearing aids to sound generators, combination hearing aids to hearing aids, and combination hearing aids to sound generators.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. Our primary outcomes were tinnitus symptom severity as measured as a global score on multi-item tinnitus questionnaire and significant adverse effects as indicated by an increase in self-reported tinnitus loudness. Our secondary outcomes were depressive symptoms, symptoms of generalised anxiety, health-related quality of life and adverse effects associated with wearing the device such as pain, discomfort, tenderness or skin irritation, or ear infections. We used GRADE to assess the quality of evidence for each outcome; this is indicated in italics.

MAIN RESULTS

This review included eight studies (with a total of 590 participants). Seven studies investigated the effects of hearing aids, four combination hearing aids and three sound generators. Seven studies were parallel-group RCTs and one had a cross-over design. In general, risk of bias was unclear due to lack of detail about sequence generation and allocation concealment. There was also little or no use of blinding.No data for our outcomes were available for any of our three main comparisons (comparing hearing aids, sound generators and combination devices with a waiting list control group, placebo or education/information only). Data for our additional comparisons (comparing these devices with each other) were also few, with limited potential for data pooling.Hearing aid only versus sound generator device onlyOne study compared patients fitted with sound generators versus those fitted with hearing aids and found no difference between them in their effects on our primary outcome, tinnitus symptom severity measured with the Tinnitus Handicap Inventory (THI) at 3, 6 or 12 months (low-quality evidence). The use of both types of device was associated with a clinically significant reduction in tinnitus symptom severity.Combination hearing aid versus hearing aid onlyThree studies compared combination hearing aids with hearing aids and measured tinnitus symptom severity using the THI or Tinnitus Functional Index. When we pooled the data we found no difference between them (standardised mean difference -0.15, 95% confidence interval -0.52 to 0.22; three studies; 114 participants) (low-quality evidence). The use of both types of device was again associated with a clinically significant reduction in tinnitus symptom severity.Adverse effects were not assessed in any of the included studies.None of the studies measured the secondary outcomes of depressive symptoms or depression, anxiety symptoms or generalised anxiety, or health-related quality of life as measured by a validated instrument, nor the newly developed core outcomes tinnitus intrusiveness, ability to ignore, concentration, quality of sleep and sense of control.

AUTHORS' CONCLUSIONS

There is no evidence to support the superiority of sound therapy for tinnitus over waiting list control, placebo or education/information with no device. There is insufficient evidence to support the superiority or inferiority of any of the sound therapy options (hearing aid, sound generator or combination hearing aid) over each other. The quality of evidence for the reported outcomes, assessed using GRADE, was low. Using a combination device, hearing aid or sound generator might result in little or no difference in tinnitus symptom severity.Future research into the effectiveness of sound therapy in patients with tinnitus should use rigorous methodology. Randomisation and blinding should be of the highest quality, given the subjective nature of tinnitus and the strong likelihood of a placebo response. The CONSORT statement should be used in the design and reporting of future studies. We also recommend the use of validated, patient-centred outcome measures for research in the field of tinnitus.

Role of preoperative air-bone gap in tinnitus outcome after tympanoplasty for chronic otitis media with tinnitus

Introduction

Previous reports indicated that middle ear surgery might partially improve tinnitus after surgery. However, until now, no influencing factor has been determined for tinnitus outcome after middle ear surgery.

Objective

The purpose of this study was to investigate the association between preoperative air-bone gap and tinnitus outcome after tympanoplasty type I.

Methods

Seventy-five patients with tinnitus who had more than 6 months of symptoms of chronic otitis media on the ipsilateral side that were refractory to medical treatment were included in this study. All patients were evaluated through otoendoscopy, pure tone/speech audiometer, questionnaire survey using the visual analog scale and the tinnitus handicap inventory for tinnitus symptoms before and 6 months after tympanoplasty. The influence of preoperative bone conduction, preoperative air-bone-gap, and postoperative air-bone-gap on tinnitus outcome after the operation was investigated.

Results and conclusion

The patients were divided into two groups based on preoperative bone conduction of less than 25 dB (n = 50) or more than 25 dB (n = 25). The postoperative improvement of tinnitus in both groups showed statistical significance. Patients whose preoperative air-bone-gap was less than 15 dB showed no improvement in postoperative tinnitus using the visual analog scale (p = 0.889) and the tinnitus handicap inventory (p = 0.802). However, patients whose preoperative air-bone-gap was more than 15 dB showed statistically significant improvement in postoperative tinnitus using the visual analog scale (p < 0.01) and the tinnitus handicap inventory (p = 0.016). Postoperative change in tinnitus showed significance compared with preoperative tinnitus using visual analog scale (p = 0.006). However, the correlation between reduction in the visual analog scale score and air-bone-gap (p = 0.202) or between reduction in tinnitus handicap inventory score and air-bone-gap (p = 0.290) was not significant. We suggest that the preoperative air-bone-gap can be a predictor of tinnitus outcome after tympanoplasty in chronic otitis media with tinnitus.

Changes in Tinnitus After Middle Ear Implant Surgery: Comparisons With the Cochlear Implant

Tinnitus is a very common symptom in patients with hearing loss. Several studies have confirmed that hearing restoration using hearing aids or cochlear implants (CIs) has a suppressive effect on tinnitus in users. The aim of this study was to analyze the effect of other hearing restoration devices, specifically the middle ear implant (MEI), on changes in tinnitus severity.

Tinnitus is a very common symptom in patients with hearing loss. The aim of this study is to analyze the effect of other hearing restoration devices, specifically the middle ear implant (MEI), on changes in tinnitus severity. The results indicate that the MEI may be as beneficial as the CI in relieving tinnitus in subjects with unilateral tinnitus accompanying hearing loss. Furthermore, this improvement may manifest as hearing restoration or habituation, rather than a direct electrical nerve stimulation, which was previously considered as the main mechanism underlying tinnitus suppression by auditory implants.

Treatment of tinnitus

PURPOSE OF REVIEW

Tinnitus, the perception of sound in the absence of a corresponding external acoustic stimulus, is a highly prevalent and frequently severely impairing disorder with worldwide impact. In this article after a short overview about epidemiology and pathophysiology the currently available treatment options will be discussed with specific consideration of the available evidence, their mechanisms of action and their limitations.

RECENT FINDINGS

During the last decades, advances in neuroimaging methods and the development of animal models have contributed to an increasing understanding of the neuronal correlates of tinnitus and have motivated the development of innovative brain-based treatment approaches for directly targeting the neuronal correlates of tinnitus. A further important development has been the insight that there exist different forms of tinnitus that differ in their pathophysiology and their response to specific treatments.

SUMMARY

Treatment of tinnitus should be based on a comprehensive diagnosis of etiologic and concomitant aspects of an individual's tinnitus. Already today a large variety of therapeutic interventions are available, which can efficiently reduce tinnitus severity. Several innovative treatment approaches are currently under development.

Consensus on Hearing Aid Candidature and Fitting for Mild Hearing Loss, With and Without Tinnitus: Delphi Review

OBJECTIVES

In many countries including the United Kingdom, hearing aids are a first line of audiologic intervention for many people with tinnitus and aidable hearing loss. Nevertheless, there is a lack of high quality evidence to support that they are of benefit for tinnitus, and wide variability in their use in clinical practice especially for people with mild hearing loss. The aim of this study was to identify a consensus among a sample of UK clinicians on the criteria for hearing aid candidature and clinical practice in fitting hearing aids specifically for mild hearing loss with and without tinnitus. This will allow professionals to establish clinical benchmarks and to gauge their practice with that used elsewhere.

DESIGN

The Delphi technique, a systematic methodology that seeks consensus amongst experts through consultation using a series of iterative questionnaires, was used. A three-round Delphi survey explored clinical consensus among a panel of 29 UK hearing professionals. The authors measured panel agreement on 115 statements covering: (i) general factors affecting the decision to fit hearing aids, (ii) protocol-driven factors affecting the decision to fit hearing aids, (iii) general practice, and (iv) clinical observations. Consensus was defined as a priori ≥70% agreement across the panel.

RESULTS

Consensus was reached for 58 of the 115 statements. The broad areas of consensus were around factors important to consider when fitting hearing aids; hearing aid technology/features offered; and important clinical assessment to verify hearing aid fit (agreement of 70% or more). For patients with mild hearing loss, the greatest priority was given by clinicians to patient-centered criteria for fitting hearing aids: hearing difficulties, motivation to wear hearing aids, and impact of hearing loss on quality of life (chosen as top five by at least 64% of panelists). Objective measures were given a lower priority: degree of hearing loss and shape of the audiogram (chosen as top five by less than half of panelists). Areas where consensus was not reached were related to the use of questionnaires to predict and verify hearing aid benefit for both hearing and tinnitus; audiometric criteria for fitting hearing aids; and safety of using loud sounds when verifying hearing aid fitting when the patient has tinnitus (agreement of <70%).

CONCLUSIONS

The authors identified practices that are considered important when recommending or fitting hearing aid for a patient with tinnitus. More importantly perhaps, they identified practical issues where there are divided opinions. Their findings inform the design of clinical trials and open up debate on the potential impact of practice differences on patient outcomes.

Hearing Aid Use and Associated Factors in South Korea

Despite the high prevalence of hearing impairment in the elderly, the rate of hearing aid use is still low. The objectives of this study were to report the nation-wide prevalence of hearing aid use in the Korean population and to determine the associated factors with hearing aid use utilizing a nationally representative data set.We obtained data from the 2010 to 2012 Korea National Health and Nutrition Examination Surveys, which were cross-sectional surveys of the civilian, noninstitutionalized population of the Republic of Korea at age ≥40 years (N = 12,709). A field survey team performed interviews as well as physical examinations. Hearing aid use was assessed using an interviewer-administered questionnaire and pure-tone audiometry was administered for all participants in a sound-attenuating booth. Prevalence of hearing aid acquisition and regular use were calculated in participants who reported perceived hearing loss and who have bilateral hearing thresholds exceeding the 40 dB hearing level. Multivariable analyses were used to examine the associated factors with hearing aid use.The prevalence of hearing aid acquisition and regular use was 17.4% and 12.6%, respectively, in South Korea. Increased hearing threshold (OR 1.05, 95% CI 1.03-1.07), severe perceived hearing loss (OR 10.73, 95% CI 4.52-25.46), annoying tinnitus (OR 3.30, 95% CI 1.61-6.74), balance problems (OR 0.39, 95% CI 0.18-0.86), and myopia (OR 0.30, 95% CI 0.12-0.76) were associated factors of regular use of hearing aids.The prevalence of hearing aid use in Korea is relatively low. Finding relevant factors of hearing aid use could provide further insight in setting up hearing-rehabilitation strategy for the elderly with significant hearing loss.

Revisiting the cochlear and central mechanisms of tinnitus and therapeutic approaches

This short review aims at revisiting some of the putative mechanisms of tinnitus. Cochlear-type tinnitus is suggested to result from aberrant activity generated before or at the cochlear nerve level. It is proposed that outer hair cells, through their role in regulating the endocochlear potential, can contribute to the enhancement of cochlear spontaneous activity. This hypothesis is attractive as it provides a possible explanation for cochlear tinnitus of different aetiologies, such as tinnitus produced by acute noise trauma, intense low-frequency sounds, middle-ear dysfunction or temporomandibular joint disorders. Other mechanisms, namely an excitatory drift in the operating point of the inner hair cells and activation of NMDA receptors, are also briefly reported. Central-type tinnitus is supposed to result from aberrant activity generated in auditory centres, i.e. in these patients, the tinnitus-related activity does not pre-exist in the cochlear nerve. A reduction in cochlear activity due to hearing loss is suggested to produce tinnitus-related plastic changes, namely cortical reorganisation, thalamic neuron hyperpolarisation, facilitation of non-auditory inputs and/or increase in central gain. These central changes can be associated with abnormal patterns of spontaneous activity in the auditory pathway, i.e. hyperactivity, hypersynchrony and/or oscillating activity. Therapeutic approaches aimed at reducing cochlear activity and/or tinnitus-related central changes are discussed.

Hearing Aid or Tinnitus Masker: Which One Is the Best Treatment for Blast-Induced Tinnitus? The Results of a Long-Term Study on 974 Patients

The aim of this longitudinal study was to explore whether a hearing aid or noise generator would be an effective audiological treatment for blast-induced chronic tinnitus. The amount of satisfaction from different hearing devices (hearing aid, noise generator, or both) during different time periods (1, 6, 12 and 24 months after fitting) was assessed. The 974 subjects enrolled in this study were Iran-Iraq war veterans, suffering from tinnitus for at least 2 years. About 84% of the subjects preferred just a hearing aid. Only 2.7% chose the noise generator, and the others preferred to use both devices. There were no significant differences between the hearing thresholds of the 3 groups. The satisfaction score for the hearing aid and combined devices increased by time but decreased for the noise generator. There was no correlation between the satisfaction score and parameters such as hearing thresholds, audiogram configuration and tinnitus pitch. We concluded that, compared with a noise generator, the most long-lasting treatment for blast-induced tinnitus is a hearing aid. The possible cause for such a performance is probably the recovery of the auditory function and neuroplasticity through the hearing aid.

Amplification with hearing aids for patients with tinnitus and co-existing hearing loss

BACKGROUND

Tinnitus is described as the perception of sound or noise in the absence of real acoustic stimulation. In the current absence of a cure for tinnitus, clinical management typically focuses on reducing the effects of co-morbid symptoms such as distress or hearing loss. Hearing loss is commonly co-morbid with tinnitus and so logic implies that amplification of external sounds by hearing aids will reduce perception of the tinnitus sound and the distress associated with it.

OBJECTIVES

To assess the effects of hearing aids specifically in terms of tinnitus benefit in patients with tinnitus and co-existing hearing loss.

SEARCH METHODS

We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; Cambridge Scientific Abstracts; ICTRP and additional sources for published and unpublished trials. The date of the search was 19 August 2013.

SELECTION CRITERIA

Randomised controlled trials and non-randomised controlled trials recruiting adults with subjective tinnitus and some degree of hearing loss, where the intervention involves amplification with hearing aids and this is compared to interventions involving other medical devices, other forms of standard or complementary therapy, or combinations of therapies, no intervention or placebo interventions.

DATA COLLECTION AND ANALYSIS

Three authors independently screened all selected abstracts. Two authors independently extracted data and assessed those potentially suitable studies for risk of bias. For studies meeting the inclusion criteria, we used the mean difference (MD) to compare hearing aids with other interventions and controls.

MAIN RESULTS

One randomised controlled trial (91 participants) was included in this review. We judged the trial to have a low risk of bias for method of randomisation and outcome reporting, and an unclear risk of bias for other criteria. No non-randomised controlled trials meeting our inclusion criteria were identified. The included study measured change in tinnitus severity (primary measure of interest) using a tinnitus questionnaire measure, and change in tinnitus loudness (secondary measure of interest) on a visual analogue scale. Other secondary outcome measures of interest, namely change in the psychoacoustic characteristics of tinnitus, change in self reported anxiety, depression and quality of life, and change in neurophysiological measures, were not investigated in this study. The included study compared hearing aid use to sound generator use. The estimated effect on change in tinnitus loudness or severity as measured by the Tinnitus Handicap Inventory score was compatible with benefits for both hearing aids or sound generators but no difference was found between the two alternative treatments (MD -0.90, 95% confidence interval (CI) -7.92 to 6.12) (100-point scale); moderate quality evidence. No negative or adverse events were reported.

AUTHORS' CONCLUSIONS

The current evidence base for hearing aid prescription for tinnitus is limited. To be useful, future studies should make appropriate use of blinding and be consistent in their use of outcome measures. Whilst hearing aids are sometimes prescribed as part of tinnitus management, there is currently no evidence to support or refute their use as a more routine intervention for tinnitus.

Prescription of hearing-aid output for tinnitus relief

OBJECTIVE

Tinnitus is a perceived sound that cannot be attributed to an external source. This study attempts to identify a prescription of amplification that is optimized as a first-fit setting for tinnitus relief.

DESIGN

Participants compared the effect of high frequency amplification on their tinnitus. Stimuli were 13 speech files with different amounts of high frequency amplification (three cut-off frequencies and four gain settings) to simulate the effects of a change in DSL(I/O) v5.0 prescription in the high frequencies.

STUDY SAMPLE

Twenty-five participants with chronic tinnitus participated in the study.

RESULTS

A 6-dB reduction to prescribed gain at 2 kHz emerged as the most preferred output (26.47% participants) to interfere with participants' tinnitus. Overall, 70.58% of the participants' preferred a 3 to 6 dB reduction in output while 29.42% preferred a similar increase across all cut-off frequencies. A trend was observed in which the higher the tinnitus pitch the more similar the preferred output to DSL(I/O) v5.0.

CONCLUSION

DSL(I/O) v5.0 appears to be a good starting point for prescription of hearing-aid output for tinnitus management. Long-term benefits of different prescriptions for tinnitus still need to be ascertained.

Long-term tinnitus suppression with linear octave frequency transposition hearing AIDS

Over the last three years of hearing aid dispensing, it was observed that among 74 subjects fitted with a linear octave frequency transposition (LOFT) hearing aid, 60 reported partial or complete tinnitus suppression during day and night, an effect still lasting after several months or years of daily use. We report in more details on 38 subjects from whom we obtained quantified measures of tinnitus suppression through visual analog scaling and several additional psychoacoustic and audiometric measures. The long-term suppression seems independent of subject age, and of duration and subjective localization of tinnitus. A small but significant correlation was found with audiogram losses but not with high frequency loss slope. Long-term tinnitus suppression was observed for different etiologies, but with a low success rate for sudden deafness. It should be noted that a majority of subjects (23) had a history of noise exposure. Tinnitus suppression started after a few days of LOFT hearing aid use and reached a maximum after a few weeks of daily use. For nine subjects different amounts of frequency shifting were tried and found more or less successful for long-term tinnitus suppression, no correlation was found with tinnitus pitch. When the use of the LOFT hearing aid was stopped tinnitus reappeared within a day, and after re-using the LOFT aid it disappeared again within a day. For about one third of the 38 subjects a classical amplification or a non linear frequency compression aid was also tried, and no such tinnitus suppression was observed. Besides improvements in audiometric sensitivity to high frequencies and in speech discrimination scores, LOFT can be considered as a remarkable opportunity to suppress tinnitus over a long time scale. From a pathophysiological viewpoint these observations seem to fit with a possible re-attribution of activity to previously deprived cerebral areas corresponding to high frequency coding.

Suppression of tinnitus in a patient with unilateral sudden hearing loss: a case report

We describe a case of a 67-year-old woman with severe disabling right-sided tinnitus, mild hyperacusis, and headache. The tinnitus was associated with sudden right hearing loss and vertigo, which occurred about 18 months before. Magnetic resonance imaging (MRI) resulted in normal anatomical structures of the cochlea and of the cranial nerves showing a partial empty sella syndrome with suprasellar cistern hernia. Angio-MR revealed a bilateral contact between the anterior-inferior cerebellar artery (AICA) and the acoustic-facial nerve with a potential neurovascular conflict. Surgery was considered unnecessary after further evaluations. The right ear was successfully treated with a combination device (hearing aid plus sound generator). Shortly after a standard fitting procedure, the patient reported a reduction of tinnitus, hyperacusis, and headache which completely disappeared at the follow-up evaluation after 3, 6, and 12 months. This paper demonstrates that the combination device resulted in a complete tinnitus and hyperacusis suppression in a patient with unilateral sensorineural sudden hearing loss. Our paper further supports the restoration of peripheral sensory input for the treatment of tinnitus associated with hearing loss in selected patients.

Ondansetron in patients with tinnitus: randomized double-blind placebo-controlled study

The aim of this study was to assess the effect of ondansetron on symptoms of patients with subjective tinnitus accompanied by sensorineural hearing loss or normal hearing. Sixty patients with a chief complaint of tinnitus (with duration of more than 3 months) were equally randomized to ondansetron or placebo for 4 weeks. The dose of ondansetron was gradually increased from 4 mg/day (one tablet) to 16 mg/day (4 tablets) during 12 days and then continued up to 4 weeks. The exact number of tablets was prescribed in the placebo group. Patients underwent audiologic examinations and filled questionnaires at baseline and after 4 weeks of treatment. Our primary outcomes were changes in Tinnitus Handicap Inventory questionnaire (THI), Tinnitus Severity Index (TSI) and visual analog scale (VAS) scores. Our secondary outcomes were the changes in depression and anxiety based on Hospital Anxiety and Depression (HADS) questionnaire, side effects, tinnitus loudness matching, tinnitus pitch matching, pure tone audiometry and speech recognition threshold (SRT). In the ondansetron and placebo groups, 27 and 26 patients completed the study, respectively. The changes in VAS (P = 0.934), THI (P = 0.776), anxiety (P = 0.313) and depression (P = 0.163) scores were not different between the groups. TSI score decreased significantly in the ondansetron compared with the placebo group (P = 0.004). Changes in tinnitus loudness matching (P = 0.75) and pitch matching (P = 0.56) did not differ between the two groups. Ondansetron, but not placebo, decreased the SRT threshold (right, P < 0.001; left, P = 0.043) and mean PTA (right, P = 0.006; left, P < 0.001). In conclusion, ondansetron reduces the severity of tinnitus hypothetically through cochlear amplification.

Auditory cortex stimulation to suppress tinnitus: mechanisms and strategies

Brain stimulation is an important method used to modulate neural activity and suppress tinnitus. Several auditory and non-auditory brain regions have been targeted for stimulation. This paper reviews recent progress on auditory cortex (AC) stimulation to suppress tinnitus and its underlying neural mechanisms and stimulation strategies. At the same time, the author provides his opinions and hypotheses on both animal and human models. The author also proposes a medial geniculate body (MGB)-thalamic reticular nucleus (TRN)-Gating mechanism to reflect tinnitus-related neural information coming from upstream and downstream projection structures. The upstream structures include the lower auditory brainstem and midbrain structures. The downstream structures include the AC and certain limbic centers. Both upstream and downstream information is involved in a dynamic gating mechanism in the MGB together with the TRN. When abnormal gating occurs at the thalamic level, the spilled-out information interacts with the AC to generate tinnitus. The tinnitus signals at the MGB-TRN-Gating may be modulated by different forms of stimulations including brain stimulation. Each stimulation acts as a gain modulator to control the level of tinnitus signals at the MGB-TRN-Gate. This hypothesis may explain why different types of stimulation can induce tinnitus suppression. Depending on the tinnitus etiology, MGB-TRN-Gating may be different in levels and dynamics, which cause variability in tinnitus suppression induced by different gain controllers. This may explain why the induced suppression of tinnitus by one type of stimulation varies across individual patients.

An active loudness model suggesting tinnitus as increased central noise and hyperacusis as increased nonlinear gain

The present study uses a systems engineering approach to delineate the relationship between tinnitus and hyperacusis as a result of either hearing loss in the ear or an imbalanced state in the brain. Specifically examined is the input-output function, or loudness growth as a function of intensity in both normal and pathological conditions. Tinnitus reduces the output dynamic range by raising the floor, while hyperacusis reduces the input dynamic range by lowering the ceiling or sound tolerance level. Tinnitus does not necessarily steepen the loudness growth function but hyperacusis always does. An active loudness model that consists of an expansion stage following a compression stage can account for these key properties in tinnitus and hyperacusis loudness functions. The active loudness model suggests that tinnitus is a result of increased central noise, while hyperacusis is due to increased nonlinear gain. The active loudness model also generates specific predictions on loudness growth in tinnitus, hyperacusis, hearing loss or any combinations of the three conditions. These predictions need to be verified by experimental data and have explicit implications for treatment of tinnitus and hyperacusis.

Tinnitus: distinguishing between subjectively perceived loudness and tinnitus-related distress

OBJECTIVES

Overall success of current tinnitus therapies is low, which may be due to the heterogeneity of tinnitus patients. Therefore, subclassification of tinnitus patients is expected to improve therapeutic allocation, which, in turn, is hoped to improve therapeutic success for the individual patient. The present study aims to define factors that differentially influence subjectively perceived tinnitus loudness and tinnitus-related distress.

METHODS

In a questionnaire-based cross-sectional survey, the data of 4705 individuals with tinnitus were analyzed. The self-report questionnaire contained items about subjective tinnitus loudness, type of onset, awareness and localization of the tinnitus, hearing impairment, chronic comorbidities, sleep quality, and psychometrically validated questionnaires addressing tinnitus-related distress, depressivity, anxiety, and somatic symptom severity. In a binary step-wise logistic regression model, we tested the predictive power of these variables on subjective tinnitus loudness and tinnitus-related distress.

RESULTS

The present data contribute to the distinction between subjective tinnitus loudness and tinnitus-related distress. Whereas subjective loudness was associated with permanent awareness and binaural localization of the tinnitus, tinnitus-related distress was associated with depressivity, anxiety, and somatic symptom severity.

CONCLUSIONS

Subjective tinnitus loudness and the potential presence of severe depressivity, anxiety, and somatic symptom severity should be assessed separately from tinnitus-related distress. If loud tinnitus is the major complaint together with mild or moderate tinnitus-related distress, therapies should focus on auditory perception. If levels of depressivity, anxiety or somatic symptom severity are severe, therapies and further diagnosis should focus on these symptoms at first.

A Randomized Double-Blind Crossover Study of Phase-Shift Sound Therapy for Tinnitus

Objective

The purpose of this study was to compare the efficacy of the treatment of tinnitus with a phase-shifting pure tone to that of the same tone treatment without phase shifting.

Study Design

A double-blind crossover randomized controlled trial.

Setting

This study was conducted at the University Medical Center Groningen.

Subjects and Methods

Twenty-two patients with predominantly tonal tinnitus underwent both intervention and control treatments. Each treatment consisted of three 30-minute sessions in 1 week. The control treatment was identical to the intervention treatment, except that the stimulus was a pure tone without phase shifting. Questionnaires, tinnitus loudness match, and annoyance and loudness ratings were used to measure treatment effects.

Results

Pure-tone treatment and phase-shift treatment had no significant effect on tinnitus according to questionnaires (Tinnitus Handicap Index, Tinnitus Reaction Questionnaire, Hospital Anxiety and Depression Scale, and Maastricht Questionnaire), audiological matching procedures, and loudness and annoyance ratings of tinnitus. Furthermore, phase-shift treatment showed no additional significant improvement in comparison with pure-tone treatment. Changes in questionnaire scores due to pure-tone and the phase-shift treatment were correlated.

Conclusion

On average across the group, both treatments failed to demonstrate a significant effect. Both treatments were beneficial for some patients. However, a positive effect was not demonstrated that could be attributed to the periodic shifting of the phase of the stimulus tone.

New criteria of indication and selection of patients to cochlear implant

Numerous changes continue to occur in cochlear implant candidacy. In general, these have been accompanied by concomitant and satisfactory changes in surgical techniques. Together, this has advanced the utility and safety of cochlear implantation. Most devices are now approved for use in patients with severe to profound unilateral hearing loss rather then the prior requirement of a bilateral profound loss. Furthermore, studies have begun utilizing short electrode arrays for shallow insertion in patients with considerable low-frequency residual hearing. This technique will allow the recipient to continue to use acoustically amplified hearing for the low frequencies simultaneously with a cochlear implant for the high frequencies. The advances in design of, and indications for, cochlear implants have been matched by improvements in surgical techniques and decrease in complications. The resulting improvements in safety and efficacy have further encouraged the use of these devices. This paper will review the new concepts in the candidacy of cochlear implant. Medline data base was used to search articles dealing with the following topics: cochlear implant in younger children, cochlear implant and hearing preservation, cochlear implant for unilateral deafness and tinnitus, genetic hearing loss and cochlear implant, bilateral cochlear implant, neuropathy and cochlear implant and neural plasticity, and the selection of patients for cochlear implant.

Anticonvulsants for tinnitus

BACKGROUND

Tinnitus is the perception of sound or noise in the absence of an external or internal acoustic stimulation. It is a common and potentially distressing symptom for which no adequate therapy exists.

OBJECTIVES

To assess the effectiveness of anticonvulsants in patients with chronic tinnitus.

SEARCH STRATEGY

We searched the Cochrane Ear, Nose and Throat Disorders Group Specialised Register, CENTRAL (2010, Issue 2), MEDLINE, EMBASE, bibliographies and additional sources for published and unpublished trials. The date of the most recent search was 26 May 2010.

SELECTION CRITERIA

We selected randomised controlled trials in patients with chronic tinnitus comparing orally administered anticonvulsants with placebo. The primary outcome was improvement in tinnitus measured with validated questionnaires. Secondary outcomes were improvement in tinnitus measured with self-assessment scores, improvement in global well-being or accompanying symptoms, and adverse drug effects.

DATA COLLECTION AND ANALYSIS

Three authors assessed risk of bias and extracted data independently.

MAIN RESULTS

Seven trials (453 patients) were included in this review. These studies investigated four different anticonvulsants: gabapentin, carbamazepine, lamotrigine and flunarizine. The risk of bias of most studies was 'high' or 'unclear'. Three studies included a validated questionnaire (primary outcome). None of them showed a significant positive effect of anticonvulsants. One study showed a significant negative effect of gabapentin compared to placebo with an increase in Tinnitus Questionnaire (TQ) score of 18.4 points (standardised mean difference (SMD) 0.82, 95% confidence interval (CI) 0.07 to 1.58). A second study showed a positive, non-significant effect of gabapentin with a difference compared to placebo of 2.4 points on the Tinnitus Handicap Inventory (THI) (SMD -0.11, 95% CI -0.48 to 0.25). When the data from these two studies are pooled no effect of gabapentin is found (SMD 0.07, 95% CI -0.26 to 0.40). A third study reported no differences on the THI after treatment with gabapentin compared to placebo (exact numbers could not be extracted from the article).A meta-analysis of 'any positive effect' (yes versus no) based on a self-assessment score (secondary outcome) showed a small favourable effect of anticonvulsants (RD 14%, 95% CI 6% to 22%). A meta-analysis of 'near or total eradication of tinnitus annoyance' showed no effect of anticonvulsants (risk difference (RD) 4%, 95% CI -2% to 11%). Side effects of the anticonvulsants used were experienced by 18% of patients.

AUTHORS' CONCLUSIONS

Current evidence regarding the effectiveness of anticonvulsants in patients with tinnitus has significant risk of bias. There is no evidence from studies performed so far to show that anticonvulsants have a large positive effect in the treatment of tinnitus but a small effect (of doubtful clinical significance) has been demonstrated.