The effect of tinnitus retraining therapy on chronic tinnitus: A controlled trial

Assessment of Treatment Efficacy in Patients with Chronic Tinnitus: An Ambispective Cohort Study

Introduction

Tinnitus, a subjective perception of sound without external stimuli, affects millions worldwide, impairing daily function and quality of life. The severity of tinnitus is influenced by associated symptoms such as stress, anxiety, depression, and insomnia. The Tinnitus Functional Index (TFI) is a validated tool for assessing tinnitus severity and treatment outcomes. Despite the lack of a definitive cure, multimodal treatments, including pharmacotherapy and Tinnitus Retraining Therapy (TRT), show promise in managing the condition.

Aim

This ambispective cohort study aimed to evaluate treatment efficacy in chronic tinnitus patients without hearing loss, using the Tinnitus Functional Index (TFI) as an assessment tool.

Methodology

Forty patients were divided into two groups: Group A received pharmacological treatment alone, while Group B received both pharmacological treatment and tinnitus retraining therapy (TRT). TFI scores were recorded at baseline, 3, 6, and 12 months.

Results

Statistical analyses revealed significant improvements in TFI scores in both groups over time, with Group B demonstrating greater improvement, indicating the efficacy of TRT.

Conclusion

Our findings underscore the importance of multimodal treatment approaches, particularly TRT, in managing chronic tinnitus without hearing loss. Further research is warranted to refine treatment protocols and enhance patient outcomes.

Clinical Practice Guideline for Management of Tinnitus: Recommendations From the US VA/DOD Clinical Practice Guideline Work Group

Importance

The most recent US clinical practice guideline (CPG) for tinnitus was published in 2014. The US Department of Veterans Affairs (VA)/US Department of Defense Tinnitus Clinical Practice Guideline Work Group recently completed a new guideline. The work group consisted of experts across disciplines who were supported by the VA Office of Quality and Patient Safety and the Defense Health Agency Clinical Quality Improvement Program. This article summarizes the first VA/US Department of Defense CPG for tinnitus management.

Methods and Observations

The guideline was based on a systematic review of clinical and epidemiological evidence. Rigorous methods determined the strength of the recommendations. Developed by a panel of multidisciplinary experts, it provides a clear explanation of the logical associations between various care options and health outcomes while rating the quality of the evidence and strength of the recommendations for 20 questions focused on evaluating and managing care for adults with bothersome tinnitus. The guideline provides an evidence-based framework for evaluating and managing care for adults with bothersome tinnitus.

Conclusions and Relevance

The CPG offers patients with tinnitus and clinicians an overview of evidence-based education and self-management, care options, and recommended outcome measures to monitor effectiveness and potentially improve patient health and well-being. Findings of a lack of sufficient evidence resulted from evaluating the quality of the body of evidence and emphasize the gaps in knowledge that need further study. Addressing these gaps may enable a comprehensive evaluation of the potential benefits and limitations of various tinnitus care options, ultimately improving patient care and clinical practice.

Assessing the efficacy of a novel bone conduction tinnitus suppression device: a 30-day pilot study on clinical and audiological outcomes

PURPOSE

This pilot study investigated the efficacy of a novel Tinnitus Retraining Therapy (TRT) device utilizing bone conduction white noise generation, in treating tinnitus in a normal hearing population.

METHODS

This study was designed as a prospective, single-arm, observational trial in an outpatient clinic at a tertiary referral center, with 30 consecutive normal hearing patients with tinnitus. Tinnitus-specific questionnaires, namely the Tinnitus Handicap Inventory (THI) and Tinnitus Functional Index (TFI), translated and adapted to European Portuguese were administered. Patients were categorized into Group A (tinnitus characteristics within the device's maximum output performance) and Group B (outside the device's maximum output performance).

RESULTS

69% of the participants showed improvement in their TFI scores, with Group A exhibiting a significant mean reduction of 10 points (p = 0.0004). The device was well-tolerated, with no adverse effects reported.

CONCLUSION

The novel bone conduction tinnitus suppression device showed promise in reducing the impact of tinnitus, particularly in patients whose tinnitus profile is within the device maximum performance output. This improvement in TFI scores in the majority of the participants, observed after just a 30-day period, highlights the potential of specifically tailored sound therapy delivered via bone conduction in tinnitus management.

Effects of tinnitus retraining therapy on patients with tinnitus: a systematic review of randomized controlled trials

PURPOSE

This review aims to explore the influences of tinnitus retraining therapy (TRT) on patients with tinnitus.

METHODS

PubMed, MEDLINE, EMBASE, CINAHL, PEDro, SCOPUS, and Web of Science were screened for randomized controlled trials (RCTs) that explored the effects of TRT on patients with tinnitus from inception to June 30, 2024. The methodological quality of the included RCTs was evaluated using the physiotherapy evidence database (PEDro) scale.

RESULTS

Fifteen studies met our eligibility criteria. A total of 2069 patients with tinnitus (mean age 52.93 years; 66% male) were involved in the present review. The quality of the selected studies ranged from 5 to 8 on the PEDro scale, with a median score of 7. TRT did not provide superior effects in treating patients with tinnitus compared to tinnitus masking (TM), tinnitus educational counselling (TED), TRT with open ear hearing aids, Tailor-made notched music training (TMNMT), partial TRT, usual care, and smart TRT.

CONCLUSIONS

TRT intervention is considered a treatment option for patients with tinnitus. Combining TRT with other interventions, such as cognitive-behavioral therapy, pharmacotherapy, or tDS, may show even greater efficacy. Additional studies are strongly required to recognize the long-term effects of TRT on tinnitus, determine who most likely would benefit from the intervention regarding tinnitus type and severity, and identify the optimal treatment protocol.

Tinnitus Retraining Therapy: In Person Versus Mobile Application Based - Two Case Scenarios

This study compares the outcomes of traditional face-to-face tinnitus retraining therapy (TRT) with mobile-based TRT in India. TRT, comprising directive counseling and sound therapy, aims to help patients habituate to tinnitus. Traditional TRT involves extensive in-person sessions, whereas mobile-based TRT employs interactive applications for weekly video counseling. The Tinnitus Handicap Inventory (THI) was used to assess tinnitus severity in two cases: Case 1 received conventional face-to-face TRT, while Case 2 received mobile-based TRT. Results indicate that mobile-based TRT is as effective as the traditional approach. After two months of therapy, Case 2 showed significant improvements in tinnitus and quality of life (QOL) due to convenient followups and self-monitoring. Mobile-based TRT is a promising alternative to face-to-face therapy.

A Review of Auditory Rehabilitation Uses in Hearing Aid-Based Therapy for Tinnitus (2013-2024)

The weight of evidence supports hearing aids playing an important role in tinnitus management. Less information is available about the role of auditory rehabilitation (AR) in the hearing aid therapy process. The research question was "what role has amplification and AR played in the management of tinnitus." To identify relevant studies, database searches of Scopus (keywords), Embase (keywords), and PubMed (title and abstract) were carried out in April/May 2024 using the following search terms [tinnitus] and [amplification] or [hearing aids]. Articles were excluded if not written in English or unavailable in full text. Reviews and protocols were excluded. Once duplicates were removed, 495 articles were screened with 58 articles being included in the review. After cataloguing, articles were divided into those that described use of AR in their methods and those that did not. AR was subcategorized into four categories and described as (1) instruction, (2) counseling, (3) sensory management, (4) perceptual training. Articles published in the last 12 years support the use of hearing aids. The use of AR in addition to amplification was common but its content, application, and contribution to outcomes were ambiguous. Augmentation of amplification benefits for tinnitus through AR presents an opportunity for future research. In future research, each AR component needs to be described in greater detail and the relative merits of different types of AR and their role in personalized therapy needs to be ascertained.

Enriched Acoustic Environment as a customized treatment for tinnitus: A non-controlled longitudinal study

Tinnitus is a heterogeneous hearing disorder with no cure at present, but some treatments, such as a combination of counselling and sound therapy, can alleviate the discomfort it causes. The sound therapy efficiency depends on both the type of sound stimulus and the time of exposure. This study describes the fundamentals of a personalized sound therapy that stimulates the auditory system with either continuous or sequential sounds whose spectra are adjusted to the hearing levels of the participants. This sound therapy is called Enriched Acoustic Environment and is assessed in a sample of 137 participants with tinnitus. Tinnitus-related distress relief was clinically relevant and statistically significant for 90% of these patients. This was quantified as a mean decrease of 24.3 points on the Tinnitus Handicap Inventory. 31% of participants were treated with sequential stimuli and achieved greater relief of distress (29.4 points on their Tinnitus Handicap Inventory score) compared to those treated with continuous sound (69%). According to these results, sequential sound seems to be optimal compared to continuous sound.

Patient-reported measures of tinnitus for individuals with neurofibromatosis type 2-related schwannomatosis: Recommendations for clinical trials

BACKGROUND

Neurofibromatosis type 2-related schwannomatosis is a genetic disease characterized by the development of bilateral vestibular schwannomas, ependymomas, meningiomas, and cataracts. Mild to profound hearing loss and tinnitus are common symptoms reported by individuals with neurofibromatosis type 2. While tinnitus is known to have a significant and negative impact on the quality of life of individuals from the general population, the impact on individuals with neurofibromatosis type 2 is unknown. Consensus regarding the selection of suitable patient-reported outcome measures for assessment could advance further research into tinnitus in neurofibromatosis type 2 patients. The purpose of this work is to achieve a consensus recommendation by the Response Evaluation in Neurofibromatosis and Schwannomatosis International Collaboration for patient-reported outcome measures used to evaluate quality of life in the domain of tinnitus for neurofibromatosis type 2 clinical trials.

METHODS

The Response Evaluation in Neurofibromatosis and Schwannomatosis Patient-Reported Outcomes Communication Subgroup systematically evaluated patient-reported outcome measures of quality of life in the domain of tinnitus for individuals with neurofibromatosis type 2 using previously published Response Evaluation in Neurofibromatosis and Schwannomatosis rating procedures. Of the 19 identified patient-reported outcome measures, 3 measures were excluded because they were not validated as an outcome measure or could not have been used as a single outcome measure for a clinical trial. Sixteen published patient-reported outcome measures for the domain of tinnitus were scored and compared on their participant characteristics, item content, psychometric properties, and feasibility for use in clinical trials.

RESULTS

The Tinnitus Functional Index was identified as the most highly rated measure for the assessment of tinnitus in populations with neurofibromatosis type 2, due to strengths in the areas of item content, psychometric properties, feasibility, and available scores.

DISCUSSION

Response Evaluation in Neurofibromatosis and Schwannomatosis currently recommends the Tinnitus Functional Index for the assessment of tinnitus in neurofibromatosis type 2 clinical trials.

Acceptability of Cognitive Behavioral Therapy for Tinnitus: A Study With Veterans and Nonveterans

PURPOSE

Cognitive behavioral therapy (CBT) is a gold standard yet underutilized treatment for tinnitus, and tinnitus is especially highly prevalent among veterans. The aims of this study were twofold: to determine (a) if CBT for tinnitus is underutilized because participants find it less acceptable than other behavioral treatments for tinnitus and (b) if veterans and nonveterans rate behavioral treatments for tinnitus differently.

METHOD

This cross-sectional study was conducted online with a sample of 277 adults in the United States who self-reported at least some level of bothersome tinnitus in the past week. The sample for this study consisted of 129 veterans and 148 nonveterans. Participants read descriptions of CBT, tinnitus retraining therapy (TRT), and mindfulness-based stress reduction (MBSR). For each treatment, presented to them in random order, they provided credibility, expectancy, and acceptability ratings.

RESULTS

Among 277 participants, 147 (53.07%) reporting gender were women, 216 (77.98%) reporting race/ethnicity were White, and 129 (46.57%) were veterans of any branch of the U.S. Armed Forces. Veteran ratings of credibility, expectancy, and acceptability were significantly lower than nonveteran ratings across treatments. There were differences in credibility, expectancy, and acceptability ratings across treatments, and post hoc testing revealed that TRT was consistently rated higher than CBT or MBSR.

CONCLUSIONS

Despite strong research support, CBT was rated as less acceptable than a different, less widely empirically supported treatment. Veterans' ratings of acceptability were lower than those of nonveterans across all treatments.

Comparative analysis of acoustic therapies for tinnitus treatment based on auditory event-related potentials

Introduction

So far, Auditory Event-Related Potential (AERP) features have been used to characterize neural activity of patients with tinnitus. However, these EEG patterns could be used to evaluate tinnitus evolution as well. The aim of the present study is to propose a methodology based on AERPs to evaluate the effectiveness of four acoustic therapies for tinnitus treatment.

Methods

The acoustic therapies were: (1) Tinnitus Retraining Therapy (TRT), (2) Auditory Discrimination Therapy (ADT), (3) Therapy for Enriched Acoustic Environment (TEAE), and (4) Binaural Beats Therapy (BBT). In addition, relaxing music was included as a placebo for both: tinnitus sufferers and healthy individuals. To meet this aim, 103 participants were recruited, 53% were females and 47% were males. All the participants were treated for 8 weeks with one of these five sounds, which were moreover tuned in accordance with the acoustic features of their tinnitus (if applied) and hearing loss. They were electroencephalographically monitored before and after their acoustic therapy, and wherefrom AERPs were estimated. The sound effect of acoustic therapies was evaluated by examining the area under the curve of those AERPs. Two parameters were obtained: (1) amplitude and (2) topographical distribution.

Results

The findings of the investigation showed that after an 8-week treatment, TRT and ADT, respectively achieved significant neurophysiological changes over somatosensory and occipital regions. On one hand, TRT increased the tinnitus perception. On the other hand, ADT redirected the tinnitus attention, what in turn diminished the tinnitus perception. Tinnitus handicapped inventory outcomes verified these neurophysiological findings, revealing that 31% of patients in each group reported that TRT increased tinnitus perception, but ADT diminished it.

Discussion

Tinnitus has been identified as a multifactorial condition highly associated with hearing loss, age, sex, marital status, education, and even, employment. However, no conclusive evidence has been found yet. In this study, a significant (but low) correlation was found between tinnitus intensity and right ear hearing loss, left ear hearing loss, heart rate, area under the curve of AERPs, and acoustic therapy. This study raises the possibility to assign acoustic therapies by neurophysiological response of patient.

The Treatment Outcome of Smart Device-Based Tinnitus Retraining Therapy: Prospective Cohort Study

BACKGROUND

Tinnitus retraining therapy (TRT) is a standard treatment for tinnitus that consists of directive counseling and sound therapy. However, it is based on face-to-face education and a time-consuming protocol. Smart device-based TRT (smart-TRT) seems to have many advantages, but the efficacy of this new treatment has been questioned.

OBJECTIVE

The aim of this study was to compare the efficacy between smart-TRT and conventional TRT (conv-TRT).

METHODS

We recruited 84 patients with tinnitus. Results were compared between 42 patients who received smart-TRT and 42 control participants who received conv-TRT. An interactive smart pad application was used for directive counseling in the smart-TRT group. The smart pad application included detailed education on ear anatomy, the neurophysiological model of tinnitus, concept of habituation, and sound therapy. The smart-TRT was bidirectional: There were 17 multiple choice questions between each lesson as an interim check. The conv-TRT group underwent traditional person-to-person counseling. The primary outcome measure was the Tinnitus Handicap Inventory (THI), and the secondary outcome measure was assessed using a visual analogue scale (VAS).

RESULTS

Both treatments had a significant treatment effect, which comparably improved during the first 2 months. The best improvements in THI were -23.3 (95% CI -33.1 to -13.4) points at 3 months and -16.8 (95% CI -30.8 to -2.8) points at 2 months in the smart-TRT group and conv-TRT group, respectively. The improvements on the VAS were also comparable: smart-TRT group: -1.2 to -3.3; conv-TRT: -0.7 to -1.7.

CONCLUSIONS

TRT based on smart devices can be an effective alternative for tinnitus patients. Considering the amount of time needed for person-to-person counseling, smart-TRT can be a cost-effective solution with similar treatment outcomes as conv-TRT.

Race/Ethnicity, Gender, and Socioeconomic Status Representation in U.S.-Based Randomized Controlled Trials of Tinnitus: A Systematic Review

PURPOSE

The purpose of this study was to investigate if peer-reviewed randomized controlled trials (RCTs) for the management/treatment of tinnitus conducted in the United States include diverse participants in terms of gender, race/ethnicity, education, occupation, and income.

METHOD

We performed a comprehensive and systematic literature search via PubMed, Web of Science, Clinical-Trials.gov, and the Cochrane Central Register of Controlled Trials. Our goal was to identify prospective RCTs of tinnitus intervention conducted in the United States from January 1994 to September 2021 and published in peer-reviewed journals.

RESULTS

A total of 2,584 studies were retrieved. Thirty-two peer-reviewed articles met all inclusion criteria. Of the included studies, approximately 96% reported participants' gender. Approximately 15% studies reported race/ethnicity information in alignment with the U.S. Census Bureau. However, an underrepresentation of both females and people of color was evident across studies. Reporting of socioeconomic status information of participants was also scarce, with only 25% studies reporting education and/or occupation of participants and 0% reporting income levels.

CONCLUSIONS

This study indicates underrepresentation and underreporting of diverse participant pools in tinnitus research. Reasons for such underrepresentation are explored. Additionally, this systematic review indicates that recent research in tinnitus portrays an optimistic trend in terms of reporting and recruitment of diverse participant groups. Sustainable strategies for including diverse research participants are essential for hearing health care equity. Research and strategies to promote this goal are discussed.

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.

Clinical practice guideline: Chronic tinnitus—diagnosis and treatment

BACKGROUND

Chronic tinnitus is a commonly occurring symptom of the auditory system. Epidemiological studies assume a lifetime prevalence in men and women of 3.5% for chronic tinnitus requiring treatment. Almost 25% of all Germans have experienced at least one episode of tinnitus. No causal therapy is yet available, but numerous treatment strategies are being pursued. Rigorous scientific assessment of these procedures is essential.

METHODS

For this exhaustive revision of the German clinical practice guideline, the literature in the medical databases PubMed and Cochrane Library, including existing guidelines from various countries, was systematically searched using keywords on the topic of chronic tinnitus. On the basis of the revised guideline, a separate guideline was written in language accessible to patients.

RESULTS

Chronic tinnitus is often associated with hearing loss, but the mental distress caused by the ear noise is another crucial element. Apart from expert counseling, the recommended treatment comprises psychotherapeutic interventions, particularly cognitive behavioral therapy (with effect sizes of 0.54 to 0.91 for reduction of the tinnitus-related distress), and measures to improve the hearing. There is insufficient evidence regarding the effects of drug treatment, sound and music therapy, and neuromodulation (magnetic stimulation or electrostimulation).

CONCLUSION

Alongside thorough and sound diagnosis and counseling, the principal treatment options for chronic tinnitus are specific cognitive behavioral therapy and expert psychotherapeutic interventions on an individual or group basis. Future-preferably interdisciplinary-research should evaluate the long-term effects of the treatment options, with particular attention to psychosomatic comorbidity.

Efficacy of Sound Therapy for Tinnitus Using an Enriched Acoustic Environment with Hearing-Loss Matched Broadband Noise

BACKGROUND

Tinnitus is a rather heterogeneous chronic condition/disorder which is difficult to treat. Some tinnitus treatments combine sound therapy with counselling. The main goal of this study is to report the efficacy of a customized sound therapy combined with counselling on a cohort of 83 tinnitus patients.

METHODS

119 tinnitus subjects, recruited between January 2018 and June 2021, were subjected to a treatment consisting of a combination of an initial counselling session and four-month sound therapy. The sound stimulus was a personalized broadband noise colored by the audiometry of the subjects. These stimuli were given to the patients in mp3 format to be heard 1 h per day over 4 months. The tinnitus severity of the patients was evaluated monthly through the validated Spanish version of the Tinnitus Handicap Inventory.

RESULTS

Of the patients, 30% (36 of 119) withdrew from the treatment before finishing, and 96% (80 of 83) of the subjects completing the therapy attained some relief after 4 months. The overall average THI decrease of these 80 participants was 23. However, when the THI was analyzed by severity scales, it was found that patients with initial mild, moderate, severe and catastrophic handicap had an average THI decrease of 14, 20, 31 and 42 points, respectively. Thus, the average THI decrease depended on the baseline severity scale of patients.

CONCLUSIONS

Consequently, the proposed treatment was demonstrated to be effective in providing clinically relevant relief in tinnitus distress patients in just 4 months.

Unification of Treatments and Interventions for Tinnitus Patients (UNITI): a study protocol for a multi-center randomized clinical trial

BACKGROUND

Tinnitus represents a relatively common condition in the global population accompanied by various comorbidities and severe burden in many cases. Nevertheless, there is currently no general treatment or cure, presumable due to the heterogeneity of tinnitus with its wide variety of etiologies and tinnitus phenotypes. Hence, most treatment studies merely demonstrated improvement in a subgroup of tinnitus patients. The majority of studies are characterized by small sample sizes, unstandardized treatments and assessments, or applications of interventions targeting only a single organ level. Combinatory treatment approaches, potentially targeting multiple systems as well as treatment personalization, might provide remedy and enhance treatment responses. The aim of the present study is to systematically examine established tinnitus therapies both alone and in combination in a large sample of tinnitus patients. Further, it wants to provide the basis for personalized treatment approaches by evaluating a specific decision support system developed as part of an EU-funded collaborative project (Unification of treatments and interventions for tinnitus patients; UNITI project).

METHODS/STUDY DESIGN

This is a multi-center parallel-arm randomized clinical trial conducted at five different clinical sites over the EU. The effect of four different tinnitus therapy approaches (sound therapy, structured counseling, hearing aids, cognitive behavioral therapy) applied over a time period of 12 weeks as a single or rather a combinatory treatment in a total number of 500 chronic tinnitus patients will be investigated. Assessments and interventions are harmonized over the involved clinical sites. The primary outcome measure focuses on the domain tinnitus distress assessed via the Tinnitus Handicap Inventory.

DISCUSSION

Results and conclusions from the current study might not only provide an essential contribution to combinatory and personalized treatment approaches in tinnitus but could also provide more profound insights in the heterogeneity of tinnitus, representing an important step towards a cure for tinnitus.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04663828 . Registered on 11 December 2020.

Neuropsychological monitoring of current acoustic therapies as alternative treatment of chronic tinnitus

At present, the majority of the top tinnitus treatments is based on sound. Sound-based therapies may become highly effective when the right patient at the correct time and the appropriate context is selected. The investigation presented here attempts to compare sound therapies based on music, retraining, neuromodulation, and binaural sounds in line with (1) neuro-audiology assessments and (2) psychological evaluations. Sound-based therapies were applied in 76 volunteers with tinnitus for 60 days. The neuro-audiology assessment was based on the estimation of the approximate entropy of the electrical neural activity. This assessment revealed that the whole frequency structure of the neural networks showed a higher level of activeness in tinnitus sufferers than in control individuals. Then psychological evaluation showed that retraining treatment tended to be the most effective sound-based therapy to reduce tinnitus perception, but it may be not recommended for individuals with anxiety. Binaural sounds and neuromodulation produced very similar effects at reducing tinnitus perception, stress and anxiety. Music treatments can be applied with caution since they may worsen the condition due to their frequency content.

Efficacy of sound therapy interventions for tinnitus management: A protocol for systematic review and network meta-analysis

BACKGROUND

Tinnitus is a common otological symptom and can be debilitating. Sound therapy has increased in popularity due to its potential for increased efficacy and fewer and milder side effects, but the available evidence is limited by the lack of randomized controlled trials comparing different sound therapies for tinnitus. Network meta-analysis (NMA) is a useful tool to compare multiple treatments when there is limited or no direct evidence available. The aim of this paper is to evaluate the efficacy and acceptability of different sound therapies for tinnitus.

METHODS AND ANALYSIS

A literature search was conducted to identify articles in EMBASE, PubMed/MEDLINE, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Chinese Biomedical Literature, and Wanfang and Weipu from inception to April 1, 2021. The Tinnitus Handicap Inventory, Tinnitus Questionnaire, and effective rate were used to assess perceived tinnitus suppression after treatment. We used Review Manager 5.4 for the standard meta-analysis; R 4.0.4 and Stata 15.1 were used for the NMA and the publication bias and sensitivity analyses.

RESULTS

The effect estimates of the direct comparisons (when available) were very similar to those of the NMA. Overall, sound stimulation alone performed better than medication alone, educational consultation alone, and no treatment. Combination therapy, such as sound stimulation plus educational consultation and sound stimulation plus drug therapy, yielded significantly better outcomes with regard to the alleviation of tinnitus than individual treatments.

CONCLUSION

This is the first NMA to evaluate and compare the effectiveness of different sound therapies for the management of tinnitus. It may help inform the selection of sound therapy and the development of guidelines in clinical practice. Future studies of sound therapy with larger sample sizes involving multiple medical centers are needed to improve the current evidence.

Effectiveness of Hearing Aid Treatment in Patients with Chronic Tinnitus: Subscale Evaluations Using the Tinnitus Functional Index and Factor Analysis

OBJECTIVES

The tinnitus functional index (TFI) is becoming a new international gold standard for tinnitus assessment. This study aimed to evaluate the efficacy of hearing aids for chronic tinnitus, using the Japanese version of the TFI, while focusing on its subscales.

MATERIALS AND METHODS

This is a retrospective study. A total of 21 patients with chronic tinnitus were included. All participants were treated with hearing aids for at least 12 months. They answered the TFI and tinnitus handicap inventory (THI) at the first visit and 12 months later. We analyzed each TFI subscale score and the overall scores of TFI and THI.

RESULTS

The overall TFI score decreased significantly after treatment (p=0.005) with moderate effect size (d=0.70). The scores of the intrusive, sense of control, sleep, and emotional subscales decreased significantly after the treatment. Large effect sizes were found in the intrusive and sense of control subscales (d=1.33 and d=1.25, respectively).

CONCLUSION

Hearing aids are highly effective for improving the intrusive and sense of control subscales in patients with tinnitus. Identifying better treatments for the small effect size subscales and combining these with the use of hearing aids could achieve a higher therapeutic effect with better outcomes.

Development and Preliminary Evaluation of the Tinnitus Severity Short Form

Purpose Tinnitus, or the perception of sounds that occur without an external sound source, is a prevalent condition worldwide. For a subset of adults, tinnitus causes significant distress and impairment. Several patient-reported outcome measures have been developed to assess severity of tinnitus distress. However, at present, the field lacks a brief measure that is sensitive to treatment change. The purpose of the current study was to develop and preliminarily validate a brief questionnaire for tinnitus severity from two existing measures of tinnitus-related distress, the Tinnitus Handicap Inventory (THI) and Tinnitus Functional Index (TFI). Method Using data from nine study samples in the United States and United Kingdom, we conducted exploratory and confirmatory factor analyses to identify a short measure with good psychometric properties. We also assessed sensitivity to treatment-related change by examining associations with change in the TFI and THI. Finally, we conducted a confirmatory factor analysis of the final short questionnaire in a new sample of adults seeking treatment for tinnitus-related distress. Results We identified 10 items from the THI and TFI that exhibited limited loadings on secondary factors. The resulting Tinnitus Severity Short Form achieved good to excellent fit, including in a unique sample of individuals seeking online treatment for tinnitus, and appeared sensitive to treatment-related change. Conclusions The Tinnitus Severity Short Form developed in the current study may be a useful tool for the assessment of subjective severity and distress associated with tinnitus, especially when patient burden is a concern. Further research is necessary to fully validate the questionnaire for the assessment of treatment-related change.

Multidisciplinary Tinnitus Research: Challenges and Future Directions From the Perspective of Early Stage Researchers

Tinnitus can be a burdensome condition on both individual and societal levels. Many aspects of this condition remain elusive, including its underlying mechanisms, ultimately hindering the development of a cure. Interdisciplinary approaches are required to overcome long-established research challenges. This review summarizes current knowledge in various tinnitus-relevant research fields including tinnitus generating mechanisms, heterogeneity, epidemiology, assessment, and treatment development, in an effort to highlight the main challenges and provide suggestions for future research to overcome them. Four common themes across different areas were identified as future research direction: (1) Further establishment of multicenter and multidisciplinary collaborations; (2) Systematic reviews and syntheses of existing knowledge; (3) Standardization of research methods including tinnitus assessment, data acquisition, and data analysis protocols; (4) The design of studies with large sample sizes and the creation of large tinnitus-specific databases that would allow in-depth exploration of tinnitus heterogeneity.

The Tinnitus Retraining Therapy Counseling Protocol as Implemented in the Tinnitus Retraining Therapy Trial

Purpose This clinical focus article is a companion to the work of Erdman et al. (2019), in which we described the rationale, development, and implementation of the standard-of-care protocol used in the Tinnitus Retraining Therapy Trial (TRTT), a multicenter, placebo-controlled, randomized, definitive efficacy trial of tinnitus retraining therapy (TRT). We now describe the historical background, development, and standardized implementation and delivery of the TRT counseling protocol (tinnitus counseling [TC]) used in the TRTT. TC is conjectured to be the key component in the TRT protocol for initiating the habituation process that reduces the response to the tinnitus signal and, ultimately, reduces its impact. In the TRTT, participants assigned to receive TC achieved > 30% reduction in the impact of tinnitus. Method and Results The design and implementation of standardized treatments in multisite randomized controlled trials presents many challenges for investigators. Here, subsequent to presenting the background, rationale, and the TRT protocol model, we describe the development, refinement, and training/certification for standardized delivery of TC in the TRTT. The primary challenges encountered while distilling and streamlining TC for standardized delivery across multiple clinicians and their replacements at six participating military treatment centers in the TRTT are considered, and the resulting counseling protocol is detailed. Conclusions The standardized and streamlined TC used in the TRTT was successful for treating debilitating tinnitus among persons with functionally adequate unaided hearing sensitivity. The structured TC protocol described here appears to be the main determinant of the significant and sizable TRT treatment effects measured in the TRTT, thus bolstering the merits of this standardized counseling approach as one model for the clinical implementation of TRT for the treatment of primary tinnitus.

Effective sound therapy using a hearing aid and educational counseling in patients with chronic tinnitus

OBJECTIVE

This study aimed to assess the effectiveness of our sound therapy with appropriate hearing aid fitting and periodic hearing aid adjustment in patients with chronic tinnitus.

METHODS

We conducted a retrospective study. The study included 490 individuals who received treatment with hearing aids for chronic tinnitus at least for 3 months. To determine the effects of tinnitus on patients' quality of life, the participants completed a series of questionnaires, including the Tinnitus Handicap Inventory (THI), Visual Analogue Scale (VAS) for loudness and annoyance, and questionnaires of subjective symptom improvement. Data were collected at entry and 3 months and 1 year after treatment initiation.

RESULTS

All 490 participants completed the questionnaires at 3 months; however, only 312 completed them at 1 year. The mean ± standard deviation THI score before treatment decreased significantly at 3 months (490 participants: 53 ± 25 to 11 ± 16 and 312 participants: 55 ± 24 to 12 ± 16) and 1 year (55 ± 24 to 9 ± 14) (P < 0.01). The mean VAS score for tinnitus loudness before treatment decreased significantly at 3 months (490 participants: 70 ± 22 to 25 ± 27 and 312 participants: 71 ± 22 to 27 ± 26) and 1 year (71 ± 22 to 21 ± 28) (P < 0.01). In addition, the mean VAS score for tinnitus annoyance before treatment decreased significantly at 3 months (490 participants: 75 ± 26 to 20 ± 26 and 312 participants: 75 ± 25 to 23 ± 27) and 1 year (75 ± 25 to 17 ± 26) (P < 0.01). Approximately 80% of patients noticed improvements in their tinnitus annoyance and loudness, as determined by their responses to the questionnaires of subjective symptom improvement.

CONCLUSION

The results of this study suggest that treatment with sound therapy may ameliorate the symptoms of chronic tinnitus associated with hearing loss.

Long-Term Results of Tinnitus Retraining Therapy in Patients Who Failed to Complete the Program

Purpose: We aimed to evaluate the results of Tinnitus Retraining Therapy (TRT) in patients who did not complete the program. Methods: We divided 90 patients who failed to complete the TRT program were into 3 groups: 36 patients who only completed the first phase of the TRT program (Missing group; M), 34 patients who attended counselling for less than 6 months (Noncompliant group; NC) and 20 patients who attended counselling for more than 6 months but did not complete the TRT program (Compliant group; C). The Tinnitus Handicap Inventory (THI), tinnitus Visual Analogue Scales (VAS) and a questionnaire regarding the reasons for dropout were obtained through a telephone survey. Results: Telephonic THI and VAS scores were significantly lower than the initial scores in the M and C groups but not in the NC group. Patients who were unsure about the effectiveness of TRT were prevalent in the NC group, and the poorest long-term THI results were registered in those patients. Conclusions: A fundamental cause of very poor TRT results was when patients were unsure about TRT. On the other hand, a single counselling session could be effective in reducing tinnitus annoyance in patients who accepted the TRT approach and trusted its efficacy.

Tinnitus: A Tingling Mystery to be Decrypted

Tinnitus is a hearing disorder that causes ringing, buzzing or hissing sensation to the patient’s auditory senses. It has become a very common complaint over the years affecting around 7-8% of the human population all over the world. The disorder causes the patients to feel irritable, annoyed, depressed, and distressed. As a result, it obstructs their sense of relaxation, enjoyment, and even their sleep - thus forcing them to avoid any social gatherings. There has been a substantial amount of work that has been carried out pertinent to this disorder. This paper reviews existing research and work done regarding Tinnitus effects, causes, and diagnosis. The numerous ways in which Tinnitus could affect an individual have been depicted. From the plethora of probable causes of this disorder, the most conceivable ones are highlighted. Moreover, this paper documents and reviews the attempts at treating Tinnitus, relevant engineering breakthroughs, and the various ways in which Tinnitus noise is suppressed – such as Tinnitus Retraining Therapy, Neuromodulation, and Signal processing approach. The manuscripts highlight the pros and cons of these methods. Over 45 research articles and other reliable internet medical sources were reviewed and these pieces of work were contrasted. These findings should help in understanding both – the disorder, as well as the situation of the patients suffering from it. Through this manuscript, an attempt was made to spread awareness about the mysterious disorder.

Presence of hearing loss is predictive of return for further stages of tinnitus therapy following initial education and counseling

OBJECTIVE

Identify clinical factors that predict the likelihood of patients returning for further evaluation and treatment following stage 1 education and counselling in a staged tinnitus habituation program.

DESIGN

Retrospective cross-sectional study. Demographics, audiometric findings and Tinnitus Handicap Inventory (THI) scores were used for predictive modelling to determine the likelihood of patients returning for subsequent therapy.

STUDY SAMPLES

One hundred and ninety consecutive patients treated in an outpatient, staged tinnitus habituation program.

RESULTS

Improvements in THI scores were observed in all subjects (n = 119, d = 0.49, p < 0.001), both for those without hearing loss (n = 13, d = 0.54, p = 0.03) and those with hearing loss (n = 106, d = 0.48, p < 0.001) following Stage 1 education and counselling. Subjects with hearing loss were 14 times more likely to return for Stage 2 evaluation (p < 0.001) following completion of Stage 1 education and counselling.

CONCLUSION

Subjects with idiopathic subjective non-pulsatile tinnitus across all degrees of tinnitus severity benefit from group education and counselling alone. Subjects with hearing loss, irrespective of most hearing loss configurations, are more likely to return for subsequent stages of the program.

Repetitive transcranial magnetic stimulation on chronic tinnitus: a systematic review and meta-analysis

BACKGROUND

Although the clinical efficacy and safety of repetitive transcranial magnetic stimulation (rTMS) in the treatment of chronic tinnitus have been frequently examined, the results remain contradictory. Therefore, we performed a systematic review and meta-analysed clinical trials examining the effects of rTMS to evaluate its clinical efficacy and safety.

METHODS

Studies of rTMS for chronic tinnitus were retrieved from PubMed, Embase, and Cochrane Library through April 2020. Review Manager 5.3 software was employed for data synthesis, and Stata 13.0 software was used for analyses of publication bias and sensitivity.

RESULTS

Twenty-nine randomized studies involving 1228 chronic tinnitus patients were included. Compared with sham-rTMS, rTMS exhibited significant improvements in the tinnitus handicap inventory (THI) scores at 1 week (mean difference [MD]: - 7.92, 95% confidence interval [CI]: - 14.18, - 1.66), 1 month (MD: -8.52, 95% CI: - 12.49, - 4.55), and 6 months (MD: -6.53, 95% CI: - 11.406, - 1.66) post intervention; there were significant mean changes in THI scores at 1 month (MD: -14.86, 95% CI: - 21.42, - 8.29) and 6 months (MD: -16.37, 95% CI: - 20.64, - 12.11) post intervention, and the tinnitus questionnaire (TQ) score at 1 week post intervention (MD: -8.54, 95% CI: - 15.56, - 1.52). Nonsignificant efficacy of rTMS was found regarding the THI score 2 weeks post intervention (MD: -1.51, 95% CI: - 13.42, - 10.40); the mean change in TQ scores 1 month post intervention (MD: -3.67, 95% CI: - 8.56, 1.22); TQ scores 1 (MD: -8.97, 95% CI: - 20.41, 2.48) and 6 months (MD: -7.02, 95% CI: - 18.18, 4.13) post intervention; and adverse events (odds ratios [OR]: 1.11, 95% CI: 0.51, 2.42). Egger's and Begg's tests indicated no publication bias (P = 0.925).

CONCLUSION

This meta-analysis demonstrated that rTMS is effective for chronic tinnitus; however, its safety needs more validation. Restrained by the insufficient number of included studies and the small sample size, more large randomized double-blind multi-centre trials are needed for further verification.

Auditory Neural Plasticity in Tinnitus Mechanisms and Management

Tinnitus, which is the perception of sound in the absence of a corresponding external acoustic stimulus, including change of hearing and neural plasticity, has become an increasingly important ailment affecting the daily life of a considerable proportion of the population and causing significant burdens for both the affected individuals and society as a whole. Here, we briefly review the epidemiology and classification of tinnitus, and the currently available treatments are discussed in terms of the available evidence for their mechanisms and efficacy. The conclusion drawn from the available evidence is that there is no specific medication for tinnitus treatment at present, and tinnitus management might provide better solutions. Therapeutic interventions for tinnitus should be based on a comprehensive understanding of the etiology and features of individual cases of tinnitus, and more high quality and large-scale research studies are urgently needed to develop more efficacious medications.

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.

Current Validated Medical Treatments for Tinnitus: Cognitive Behavioral Therapy

Tinnitus distress results from a weave of physical and psychological processes. Reducing the power of the psychological processes will therefore reduce the degree of suffering. The main psychological therapy in this context is cognitive behavioral therapy (CBT). This seeks to understand and change the influence of thinking processes, including information processing biases, and the behaviors that these motivate, on the experience of tinnitus. The results of systematic reviews and meta-analyses indicate that CBT is the tinnitus management approach for which there is the most robust evidence. In spite of this, it remains difficult to access for people with tinnitus.

Regulation of auditory plasticity during critical periods and following hearing loss

Sensory input has profound effects on neuronal organization and sensory maps in the brain. The mechanisms regulating plasticity of the auditory pathway have been revealed by examining the consequences of altered auditory input during both developmental critical periods—when plasticity facilitates the optimization of neural circuits in concert with the external environment—and in adulthood—when hearing loss is linked to the generation of tinnitus. In this review, we summarize research identifying the molecular, cellular, and circuit-level mechanisms regulating neuronal organization and tonotopic map plasticity during developmental critical periods and in adulthood. These mechanisms are shared in both the juvenile and adult brain and along the length of the auditory pathway, where they serve to regulate disinhibitory networks, synaptic structure and function, as well as structural barriers to plasticity. Regulation of plasticity also involves both neuromodulatory circuits, which link plasticity with learning and attention, as well as ascending and descending auditory circuits, which link the auditory cortex and lower structures. Further work identifying the interplay of molecular and cellular mechanisms associating hearing loss-induced plasticity with tinnitus will continue to advance our understanding of this disorder and lead to new approaches to its treatment.

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During CPs, brain plasticity is enhanced and sensitive to acoustic experience.

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Enhanced plasticity can be reinstated in the adult brain following hearing loss.

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Molecular, cellular, and circuit-level mechanisms regulate CP and adult plasticity.

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Plasticity resulting from hearing loss may contribute to the emergence of tinnitus.

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Modifying plasticity in the adult brain may offer new treatments for tinnitus.

Reflections on the Last 25 Years of the American Otological Society and Thoughts on its Future

PURPOSE

To review contributions of the American Otological Society (AOS) over the most recent quarter century (1993-2018) and to comment on possible future evolution of the field during the quarter century to come.

METHODS

Retrospective review of selected topics from the AOS transactions, distinguished lectureships over the past 25 years, and selective reflection by the authors. Speculation on potential advances of the next quarter century derived from emerging topics in the current literature and foreseeable trends in science and technology are also proffered for consideration (and possible future ridicule).

RESULTS

Integration of multiple disciplines including bioengineering, medical imaging, genetics, molecular biology, physics, and evidence based medicine have substantially benefitted the practice of otology over the past quarter century. The impact of the contributions of members of the AOS in these developments cannot be over estimated.

CONCLUSIONS

Further scientific advancement will certainly accelerate change in the practice of otologic surgery and medicine over the coming decade in ways that will be marvelous to behold.

Effect of Tinnitus Retraining Therapy vs Standard of Care on Tinnitus-Related Quality of Life: A Randomized Clinical Trial

Importance

Tinnitus retraining therapy (TRT) is an internationally recognized, but controversial, protocol of uncertain efficacy that uses tinnitus-specific educational counseling (TC) and sound therapy (ST) to reduce the patient's tinnitus-evoked negative reaction to, and awareness of, tinnitus.

Objective

To compare the efficacy of TRT and its components, ST and TC, with the standard of care (SoC) in reducing the negative effect of tinnitus on quality of life.

Design, Setting, and Participants

A randomized, placebo-controlled, multicenter phase 3 trial was conducted from August 4, 2011, to June 20, 2017, at 6 US military hospitals, the study chairs' office, and a data coordinating center, among 151 active-duty and retired military personnel and dependents with functionally adequate hearing sensitivity and moderate to severe subjective tinnitus. All analyses were based on intention to treat.

Interventions

Central randomized allocation to TRT (TC and ST with conventional sound generators), partial TRT (TC with placebo sound generators), or SoC.

Main Outcomes and Measures

The primary outcome was mean change on the Tinnitus Questionnaire (TQ), assessed longitudinally between baseline and 18 months after start of therapy. The secondary outcomes were changes in TQ subscales, Tinnitus Functional Index (TFI), and Tinnitus Handicap Inventory (THI) total and subscales, as well as a 10-point visual analog scale (VAS).

Results

Among the 151 participants in the study (44 women and 107 men; mean [SD] age, 50.6 [11.3] years), 51 were randomized to receive TRT, 51 to receive partial TRT, and 49 to receive standard of care. Longitudinal analyses showed no difference between partial TRT or TRT compared with SoC, or partial TRT compared with TRT, on TQ, TFI, or THI total scores. Comparison of changes in mean score from baseline to the 18-month visit also showed no difference between treatment groups. Significant improvement was observed at 18 months in all treatment groups on TQ scores for TRT (effect size, -1.32; 95% CI, -1.78 to -0.85), partial TRT (effect size, -1.16; 95% CI, -1.56 to -0.76), and SoC (effect size, -1.01; 95% CI, -1.41 to -0.61). Compared with baseline scores, at 18 months there were reductions in scores by 7 points or more on the TQ score for 86 of 111 participants (77.55%; 95% CI, 69.7%-85.2%), 13 points or more on the TFI for 52 of 111 participants (46.8%; 95% CI, 37.6%-56.1%), 7 points or more on the THI for 63 of 111 participants (56.8%; 95% CI, 47.5%-66.0%), and 2 points or more on the VAS for 45 of 93 participants (48.4%; 95% CI, 38.2%-58.5%).

Conclusions and Relevance

There were few differences between treatment groups. About half of participants showed clinically meaningful reductions in the effect of tinnitus.

Trial Registration

ClinicalTrials.gov identifier: NCT01177137.

Clinical Efficacy of Tinnitus Retraining Therapy Based on Tinnitus Questionnaire Score and Visual Analogue Scale Score in Patients with Subjective Tinnitus

Objective

Tinnitus is the annoying sensation of sound perception without acoustic stimulus. Tinnitus retraining therapy (TRT) is the habituation therapy used for the management of chronic subjective tinnitus. The objective of the study is to describe TRT and to evaluate its efficacy in patients with subjective tinnitus.

Methods

In total, 58 patients with tinnitus who did not respond to medications were enrolled in the TRT program. TRT included counseling as described in the neurophysiological model of tinnitus and sound therapy (aided or unaided) for six months. The tinnitus severity grade (TSG) 1-5, based on a validated tinnitus questionnaire score (TQS), and the visual analogue scale (VAS) score were documented before and after therapy.

Results

Before TRT, 53 patients (91.3%) exhibited TSG 3-5, and the average VAS score was 6.7±2.1. After TRT for two months, 49 patients (84.4%) showed TSG 1-3, and the average VAS score was 3.2±2.4. After six months of TRT, most of the patients found remarkable improvement in the symptoms, and 51 patients (87.9%) exhibited TSG 1-2, and the average VAS score was 2.1±2.6. Statistically significant difference was found in TSG and VAS score before and after TRT. Statistically significant correlation was observed between TSG and VAS score.

Conclusion

TRT is an useful approach for amelioration of tinnitus. TQS is a very effective, cheap, and easy method to help otologists to grade the patients as per the severity of symptoms.

A Pilot Randomized Controlled Trial of Transcutaneous Electrical Nerve Stimulation for Patients With Acute Tinnitus

BACKGROUND

This pilot study aimed to evaluate the feasibility effectiveness and safety of transcutaneous electrical nerve stimulation (TENS) for patients with acute tinnitus.

METHODS

A total of 46 eligible patients with acute tinnitus were entered and included in this randomized controlled trial. All the included patients were equally and randomly divided into a verum TENS group and a sham TENS group, each group 23 participants. All patients received parenteral intramuscular therapy of 1 ml Vitamin B12 weekly for a total of 4 weeks. In addition, they also underwent verum or sham TENS 30 min daily, 3 times weekly for 4 weeks. The primary efficacy endpoint was measured by the Tinnitus Severity Scale (TSS) and Tinnitus Questionnaire (TQ) sum score. The secondary efficacy endpoints were assessed by the Tinnitus Handicap Inventory (THI), 12-Item Short Form Health Survey (SF-12) questionnaire, and adverse events. All outcome efficacy endpoints were measured at baseline and after 4 weeks of treatment.

RESULTS

After 4-week treatment, the patients undergoing verum TENS showed statistically efficacy of symptoms relief, as measured by the scales of TSS (P < .01), TQ (P < .01), and THI (P < .01), and improvement of quality of life, as assessed by the SF-12 (P < .01), compared with patients receiving sham TENS. In addition, no adverse events related to the treatment were recorded in either group.

CONCLUSIONS

The results of this study showed that verum TENS may benefit patients with acute tinnitus after 4 weeks of treatment.

Drug-Induced Ototoxicity: Diagnosis and Monitoring

Ototoxicity diagnosis and management has historically been approached using a variety of methods. However, in recent years a consensus on useful and practical approaches has been developed through clinical guidelines of the American Speech Language Hearing Association, the American Academy of Audiology, and multiple clinical trials published in peer-reviewed literature. Some of the guidelines and approaches are used to detect and monitor ototoxicity, while others are used to grade adverse events. Some of the audiologic measures are primary, while others are adjunct measures and may be tailored to the specific needs of the patient or clinical trial. For some types of monitoring, such as drug-induced tinnitus or dizziness, validated paper survey instruments can be both sensitive and easy for fragile patients. This review addresses the characteristics of some of the most common clinical ototoxins and the most common methods for detecting and monitoring ototoxicity in clinical practice and clinical trials.

Reduced sound-evoked and resting-state BOLD fMRI connectivity in tinnitus

The exact neurophysiological basis of chronic tinnitus, which affects 10-15% of the population, remains unknown and is controversial at many levels. It is an open question whether phantom sound perception results from increased central neural gain or not, a crucial question for any future therapeutic intervention strategies for tinnitus. We performed a comprehensive study of mild hearing-impaired participants with and without tinnitus, excluding participants with co-occurrences of hyperacusis. A right-hemisphere correlation between tinnitus loudness and auditory perceptual difficulty was observed in the tinnitus group, independent of differences in hearing thresholds. This correlation was linked to reduced and delayed sound-induced suprathreshold auditory brain responses (ABR wave V) in the tinnitus group, suggesting subsided rather than exaggerated central neural responsiveness. When anatomically predefined auditory regions of interest were analysed for altered sound-evoked BOLD fMRI activity, it became evident that subcortical and cortical auditory regions and regions involved in sound detection (posterior insula, hippocampus), responded with reduced BOLD activity in the tinnitus group, emphasizing reduced, rather than increased, central neural gain. Regarding previous findings of evoked BOLD activity being linked to positive connectivities at rest, we additionally analysed r-fcMRI responses in anatomically predefined auditory regions and regions associated with sound detection. A profound reduction in positive interhemispheric connections of homologous auditory brain regions and a decline in the positive connectivities between lower auditory brainstem regions and regions involved in sound detection (hippocampus, posterior insula) were observed in the tinnitus group. The finding went hand-in-hand with the emotional (amygdala, anterior insula) and temporofrontal/stress-regulating regions (prefrontal cortex, inferior frontal gyrus) that were no longer positively connected with auditory cortex regions in the tinnitus group but were instead positively connected to lower-level auditory brainstem regions. Delayed sound processing, reduced sound-evoked BOLD fMRI activity and altered r-fcMRI in the auditory midbrain correlated in the tinnitus group and showed right hemisphere dominance as did tinnitus loudness and perceptual difficulty. The findings suggest that reduced central neural gain in the auditory stream may lead to phantom perception through a failure to energize attentional/stress-regulating networks for contextualization of auditory-specific information. Reduced auditory-specific information flow in tinnitus has until now escaped detection in humans, as low-level auditory brain regions were previously omitted from neuroimaging studies.

TRIAL REGISTRATION

German Clinical Trials Register DRKS0006332.