Tinnitus and its current treatment–Still an enigma in medicine

Acupuncture for Tinnitus: A Scoping Review of Clinical Studies

BACKGROUND

Acupuncture treatment for tinnitus has received attention owing to its potential as an alternative to conventional treatment modalities. We conducted a scoping review to identify detailed information on acupuncture treatment methods used in clinical studies and to provide useful information for practitioners, patients, and researchers.

METHODS

MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), Embase, Oriental Medicine Advanced Searching Integrated System (OASIS), Korean Research Information Sharing Service (RISS), DataBase Periodical Information Academic (DBPIA), and the China National Knowledge Infrastructure (CNKI) were searched from their inception to December 2023. This review included single-arm trials, open-label randomized controlled trials (RCTs), and double-blind RCTs using needle-type acupuncture to treat tinnitus in English, Chinese, and Korean. We investigated basic and detailed information on the acupuncture treatment methods, assessment methods, and study outcomes. Network analysis was also conducted to evaluate the centrality between acupoints in the double-blind RCTs.

RESULTS

We included 106 articles. There were 11 single-arm trials, 90 open-label RCTs, and 5 double-blind RCTs. Most (89.6%) of these studies were conducted in China. Manual acupuncture was the most common type of acupuncture in treatment group. A total of 119 acupuncture points were used 1,138 times. The most frequently used acupoints were local points around the ear (TE17, GB2, SI19, and TE21). Both local and distant acupoints were used simultaneously in these studies. The treatment duration of 20-39 days, 10 to 19 sessions of treatment, the mean acupuncture duration of 30 min, needle diameter of 0.30 mm × 40 mm, and needling depth over 30 mm and less than 50 mm were confirmed as the most common.

CONCLUSION

These study outcomes will enable future acupuncture studies on tinnitus to perform more effective and standardized acupuncture treatments in selecting acupoints and procedures. Furthermore, the study has implications for informing clinicians and students about more impactful acupuncture strategies for addressing tinnitus.

Hintergrund

Die Anwendung von Akupunktur bei Tinnitus erhält seit einiger Zeit Aufmerksamkeit als potenzielle Alternative zu konventionellen Behandlungsmodalitäten. Wir führten einen Scoping-Review durch, um detaillierte Informationen zu den in klinischen Studien angewandten Akupunktur-Behandlungsmethoden zu sammeln und nützliche Informationen für Praktiker, Patienten und Forscher bereitzustellen.

Methoden

MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), Embase, Oriental Medicine Advanced Searching Integrated System (OASIS), Korean Research Information Sharing Service (RISS), DataBase Periodical Information Academic (DBPIA) und die China National Knowledge Infrastructure (CNKI) wurden von ihrem jeweiligen Beginn bis Dezember 2023 durchsucht. In diese Übersichtsarbeit wurden einarmige Studien, offene, randomisierte, kontrollierte Studien (RCTs) sowie doppelt verblindete RCTs zu Nadel-Akupunktur zur Behandlung von Tinnitus in englischer, chinesischer und koreanischer Sprache einbezogen. Wir untersuchten grundlegende und detaillierte Informationen zu den Akupunktur-Behandlungsmethoden, Untersuchungsmethoden und Studienergebnissen. Außerdem wurden Netzwerkanalysen zur Beurteilung der Zentralität zwischen Akupunkten in den doppelt verblindeten RCTs durchgeführt.

Ergebnisse

106 Artikel wurden eingeschlossen. Sie behandelten 11 einarmige Studien, 90 offene RCTs und 5 doppelt verblindete RCTs. Die meisten (89,6%) dieser Studien waren in China durchgeführt worden. Manuelle Akupunktur war die häufigste Form der Akupunktur in den Behandlungsgruppen. 119 Akupunkturpunkte wurden insgesamt 1’138 Mal verwendet. Die am häufigsten verwendeten Akupunkte waren lokale Punkte im Bereich des Ohrs (TE17, GB2, SI19 und TE21). Jedoch wurden in den Studien lokale und entfernte Akupunkte gleichzeitig angewendet. Außerdem wurde festgestellt, dass die Behandlungsdauer am häufigsten 20 bis 39 Tage betrug, die Zahl der Sitzungen 10 bis 19, die mittlere Akupunkturdauer 30 Minuten, die Nadelgröße 0.30 mm × 40 mm und die Einstichtiefe zwischen 30 mm und weniger als 50 mm.

Schlussfolgerung

Diese Studienergebnisse bieten eine Grundlage für künftige Studien zu Akupunktur bei Tinnitus, um durch die Auswahl der Akupunkte und Verfahren wirksamere und standardisierte Akupunkturbehandlungen durchzuführen. Darüber hinaus hat die Studie Implikationen für die Aufklärung von Praktikern und Schülern über wirkungsvollere Akupunkturstrategien zur Behandlung von Tinnitus.

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.

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.

A data-driven approach to clinical decision support in tinnitus retraining therapy

Background

Tinnitus, known as “ringing in the ears”, is a widespread and frequently disabling hearing disorder. No pharmacological treatment exists, but clinical management techniques, such as tinnitus retraining therapy (TRT), prove effective in helping patients. Although effective, TRT is not widely offered, due to scarcity of expertise and complexity because of a high level of personalization. Within this study, a data-driven clinical decision support tool is proposed to guide clinicians in the delivery of TRT.

Methods

This research proposes the formulation of data analytics models, based on supervised machine learning (ML) techniques, such as classification models and decision rules for diagnosis, and action rules for treatment to support the delivery of TRT. A knowledge-based framework for clinical decision support system (CDSS) is proposed as a UI-based Java application with embedded WEKA predictive models and Java Expert System Shell (JESS) rule engine with a pattern-matching algorithm for inference (Rete). The knowledge base is evaluated by the accuracy, coverage, and explainability of diagnostics predictions and treatment recommendations.

Results

The ML methods were applied to a clinical dataset of tinnitus patients from the Tinnitus and Hyperacusis Center at Emory University School of Medicine, which describes 555 patients and 3,000 visits. The validated ML classification models for diagnosis and rules: association and actionable treatment patterns were embedded into the knowledge base of CDSS. The CDSS prototype was tested for accuracy and explainability of the decision support, with preliminary testing resulting in an average of 80% accuracy, satisfactory coverage, and explainability.

Conclusions

The outcome is a validated prototype CDS system that is expected to facilitate the TRT practice.

The effects of photobiomodulation therapy in individuals with tinnitus and without hearing loss

To verify the effect of photobiomodulation therapy (PBMT) in individuals with chronic tinnitus without hearing loss, 20 patients who met the inclusion criteria were randomly divided into group 1: active low-level laser (LLL) and group 2: equipment without laser (placebo). Upon anamnesis, data collection, and audiological exams, the Tinnitus Handicap Inventory (THI) and the Visual-Analog Scale (EVA) were applied to measure the level of discomfort with tinnitus and the level of discomfort before and after laser treatment. The protocol used included 12 active LLL sessions for group 1 and not active for group 2, varying red and infrared wavelengths. There was a reduction in the disadvantage of individuals with tinnitus after the intervention and between the initial and final sessions, regardless of the intervention, although group 1 showed a greater reduction than group 2, regardless of point in time of assessment and number of session. There was no statistical difference as to group and point in time for the high-frequency audiometry and acuphenometry outcomes. Individuals with chronic tinnitus reduced the complaint, regardless of point in time and group of intervention; however, the group that received PBMT improved the level of satisfaction, regardless of point in time of assessment and number of session.

Audiologists’ presbycusis and associated tinnitus counselling practices within the KwaZulu-Natal province

Background

Objectives

Method

Results

Conclusion

Patient’s perceptions of presbycusis and associated tinnitus counselling practices within the KwaZulu-Natal province

Background

Counselling manages the psychosocial effects of presbycusis and associated tinnitus, which is best conducted through patient-centred care (PCC). However, there is a paucity of research on implementing PCC within audiology and on patients’ perceptions of counselling practice, making the focus on patient benefit and satisfaction crucial. Furthermore, PCC has been documented to be suitable in addressing the psychosocial effects of hearing loss and associated tinnitus, as it focuses on the adult patient playing an integral part of the management processes, providing improved patient outcomes.

Objectives

This study aimed to explore patients’ perceptions of presbycusis and associated tinnitus counselling practices by audiologists within KwaZulu-Natal (KZN).

Method

Qualitative phenomenological semi-structured telephonic interviews were conducted through purposive sampling, consisting of seven patients with presbycusis and associated tinnitus who were recruited from private and public facilities in KZN. Data were analysed through hybrid thematic analysis following Braun and Clark’s steps.

Results

Six categories were identified: perceptions on counselling methods, efficacy and tools, audiological rehabilitative training, multicultural sensitivity, patient satisfaction and recommendations on improving counselling practices as PCC adaptation. Themes were then extracted from these categories. The overall outcome of the study found that patients had positive perceptions of methods and tools, and audiologists were viewed as adequately trained. Furthermore, they were satisfied and benefitted from counselling practices and found clinicians to be culturally sensitive in their practice. However, recommendations were made towards linguistic sensitivity and satisfaction evaluations.

Conclusion

Therefore, implementing PCC into counselling practice may achieve positive patient perceptions, thus highlighting the need to identify barriers and improve the implementation of PCC into practice, especially in resource-constrained contexts.

Efficacy and safety of single- and repeated-selurampanel dosing for 2 weeks in patients with chronic subjective tinnitus: Results of a randomized, double-blind, placebo-controlled, cross-over, proof-of-concept phase IIa study

To evaluate efficacy and safety of BGG492 (selurampanel; an orally active, competitive AMPA glutamate receptor antagonist) in patients with moderate-to-catastrophic chronic subjective tinnitus. Study (NCT01302873) enrolled patients with subjective tinnitus based on THI severity grade 3, 4 or 5 (moderate, severe or catastrophic), and those with chronic (>6 and <36 months) tinnitus. Primary endpoints were clinical status of tinnitus using TBF-12 and tinnitus loudness using VAS after multiple dose 2-week BGG492 treatment. Safety was assessed by recording all adverse events (AEs). After a single dose of BGG492 VAS scores for tinnitus loudness (P=0.012) and tinnitus annoyance (P=0.004) were significantly reduced vs placebo. After 2 weeks treatment a significantly greater proportion of patients showed improvement of ≥4 points from baseline in TBF-12 (stringent responder definition) with BGG492 vs placebo (26.7% [n=23] vs 14% [n=12], respectively; odds ratio [OR] (90% CI):2.30 (1.10, 4.83); P=0.064), fulfilling proof-of-concept achievement criteria. No notable difference in proportion of responders to BGG492 vs placebo was observed as assessed using VAS (26.7% [n=23] vs 27.6% [n=24], respectively; OR (90% CI):0.94 (0.52, 1.67); P=0.848). Dizziness was the most frequently reported AE in 50% [n=21] and 31.5% [n=17] patients on BGG492 100 and 50mg TID, respectively vs 9.6% [n=9] on placebo. In conclusion, BGG492 showed reduction of both tinnitus loudness and annoyance after a single dose and reduction of tinnitus handicap after 2 weeks of treatment in patients with chronic subjective tinnitus, thereby supporting further clinical investigation of AMPA receptor antagonists with an improved benefit/risk ratio. A dose of 100mg TID BGG492 showed higher efficacy but somewhat lower tolerability compared to 50mg TID.

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.

Acupuncture for tinnitus: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To evaluate the efficacy/effectiveness of acupuncture for the treatment of tinnitus.

METHODS

Four English and four Chinese databases were searched for randomized controlled trials (RCTs) of acupuncture for tinnitus published before 30 September 2018. RCTs applying acupuncture alone compared with conventional treatments, sham acupuncture, or no treatment, as well as acupuncture plus conventional treatments compared with conventional treatments alone, were included. The primary outcome was the visual analogue scale (VAS). Secondary outcomes included tinnitus handicap inventory (THI) and tinnitus severity index (TSI) scores. Meta-analysis was conducted using RevMan V5.3 software. The protocol was registered in the PROSPERO database (ref. CRD42018108692).

RESULTS

Eight studies involving 504 participants were included. Meta-analysis showed no significant differences in the VAS score (mean difference (MD) = -1.81, 95% confidence interval (CI) = -3.69 to 0.07; p = 0.06) between the acupuncture and control groups. However, favorable effects of acupuncture on changes in THI score (MD = -10.11, 95% CI = -12.74 to -7.48; p < 0.001) and TSI score (MD = -8.36, 95% CI = -8.87 to -7.86; p < 0.001) were found.

CONCLUSION

Acupuncture had no significant effect on the primary outcome of VAS score compared with control treatment; however, positive effects on secondary outcomes (THI and TSI score) were observed in acupuncture versus control groups. Due to the low quality and small sample size of the included trials, the level of evidence was insufficient to draw any definitive conclusions. Further rigorous and high-quality studies with larger sample sizes should be conducted to confirm the efficacy/effectiveness of acupuncture for tinnitus.

Exploring tinnitus heterogeneity

INTRODUCTION

Tinnitus experiences differ widely. A greater understanding of the core processes underlying these variations is needed. Moreover, meaningful definitions for different subgroups are required to better manage this heterogeneous population. The objective of the present research was to contribute toward the understanding of tinnitus heterogeneity by identifying factors that can predict tinnitus severity and to ascertain if distinct subgroups of tinnitus presentation can be identified.

METHODS

This cross-sectional study consisted of 326 adults subdivided into subgroups of those with mild tinnitus (n=32; 10%), significant tinnitus (n=99; 30%) and severe tinnitus (n=195; 60%) according to their scores from the Tinnitus Functional Index. Multiple regression was used to identify factors associated with tinnitus severity. These factors included personal traits, tinnitus-related traits, treatment modalities and clinical comorbidities.

RESULTS

Insomnia, hearing distress, and anxiety were the best predictors of tinnitus severity (explaining 53% of the variability). These comorbidities were stronger predictors than any demographical factors (that explained 11% of the variability). Distinct subgroups based on tinnitus severity (mild, significant, and severe) and anxiety levels were evident. Those with severe tinnitus had significantly more severe comorbidities compared with the mild and significant groups.

CONCLUSIONS

This study highlights that people with tinnitus could initially be grouped according to tinnitus severity to direct further management. Those with higher tinnitus severity should receive more immediate and intensive care. Due to the strong associations between tinnitus severity and tinnitus-related comorbidities (e.g., insomnia, hearing disability, and anxiety), tinnitus assessment and interventions should focus on these comorbidities.

Prevalence of Persistent Tinnitus and Dizziness in an Elderly Population in Southern Taiwan

OBJECTIVES

Tinnitus and dizziness are common among the elderly. The conditions may increase depression, and patients may become susceptible to falls, thereby affecting the quality of life of the geriatric population. Investigating the prevalence of persistent tinnitus and chronic/recurrent dizziness in an elderly population and analyzing the association of certain comorbidities with tinnitus and dizziness in southern Taiwan were the main purposes of this study.

MATERIALS AND METHODS

This was a cross-sectional study performed in a metropolitan hospital. Hearing tests were conducted in a total of 597 volunteers aged ≥65 years involving 322 (53.9%) men and 275 (46.1%) women recruited in the study. The pure tone average (PTA) and hearing handicap (HH) score were calculated. Patients completed questionnaires regarding the history of hypertension and diabetes and symptoms of tinnitus and dizziness. The association of gender, age, PTA/HH, body mass index (BMI), hypertension, diabetes, and metabolic syndrome (MetS) with tinnitus and dizziness were analyzed.

RESULTS

The prevalence of persistent tinnitus and chronic/recurrent dizziness was 32.0% and 24.1%, respectively. Tinnitus or dizziness were not associated with age, BMI, hypertension, diabetes, and MetS but was associated with hearing impairment. Women and those with fasting glucose levels <100 mg/dL were more likely to experience dizziness.

CONCLUSION

Persistent tinnitus and dizziness were common in an elderly population in southern Taiwan. These findings may help develop strategies to promote the quality of life in the elderly population.

Management of adult patients with tinnitus: Preparedness, perspectives and practices of audiologists

Background

Audiologists, globally, are generally challenged when assessing and creating intervention plans to help patients suffering from tinnitus. Tinnitus is very common among individuals and may significantly affect one’s quality of life, especially if not addressed by health care professionals. In South Africa, there seems to be limited published studies regarding the current practices of tinnitus management by audiologists. This is mainly because of limited training and a lack of guidelines and strategies for the management of tinnitus. In particular, some participants reported being unfamiliar on how to approach the identification of tinnitus and difficulty is also encountered when counselling tinnitus patients.

Aim

The aim of this study was to describe the preparedness, perspectives and practices of audiologists who manage adult patients with tinnitus.

Method

Two hundred and forty-three registered Health Professions Council of South Africa (HPCSA) participants were involved in the study by responding to an electronic questionnaire survey. Data were collected online from Survey Monkey and were exported to Statistical Packages for the Social Sciences (SPSS) (Version 23) for statistical analysis. Data were analysed using descriptive and inferential statistics. Closed-ended questions were analysed within a quantitative framework and thematic analysis for open-ended questions that were descriptively quantified.

Results

The results of the study are presented according to the objectives. Approximately 44% of participants (44.3%) disagreed that the undergraduate university training had sufficiently prepared them to manage adult patients with tinnitus. Very few (12.3%) had the opportunity to attend specialist training on how to assess patients with tinnitus. Similarly, only 11.6% received any specialist training with regard to tinnitus intervention. With regard to its overall management, 49.4% felt adequately informed in the assessment of patients with tinnitus, while a further 39.2% rated their experience as being limited with regard to tinnitus intervention. There is no statistical significance relationship between participants’ years of experience and tinnitus intervention (p = 0.075). Most participants did not follow any standard guidelines for its management. Some participants (26.8%) reported that further education and training are required in the overall management of patients with tinnitus, while a further 17.7% required training in all areas of tinnitus.

Conclusion

The feedback relating to the study suggests that overall management of tinnitus seems to be a challenge among South African audiologists, irrespective of their years of experience. Audiologists in the study perceived that tinnitus services are limited mainly because of a lack of or limited knowledge, training and guidelines, these being affected by contextual restraints.

A Study of Social Media Utilization by Individuals With Tinnitus

PURPOSE

As more people experience tinnitus, social awareness of tinnitus has consequently increased, due in part to the Internet. Social media platforms are being used increasingly by patients to seek health-related information for various conditions including tinnitus. These online platforms may be used to seek guidance from and share experiences with individuals suffering from a similar disorder. Some social media platforms can also be used to communicate with health care providers. The aim of this study was to investigate the prevalence of tinnitus-related information on social media platforms.

METHOD

The present investigation analyzed the portrayal of tinnitus-related information across 3 social media platforms: Facebook (pages and groups), Twitter, and YouTube. We performed a comprehensive analysis of the platforms using the key words "tinnitus" and "ringing in the ears." The results on each platform were manually examined by 2 reviewers based on social media activity metrics, such as "likes," "followers," and "comments."

RESULTS

The different social media platforms yielded diverse results, allowing individuals to learn about tinnitus, seek support, advocate for tinnitus awareness, and connect with medical professionals. The greatest activity was seen on Facebook pages, followed by YouTube videos. Various degrees of misinformation were found across all social media platforms.

CONCLUSIONS

The present investigation reveals copious amounts of tinnitus-related information on different social media platforms, which the community with tinnitus may use to learn about and cope with the condition. Audiologists must be aware that tinnitus sufferers often turn to social media for additional help and should understand the current climate of how tinnitus is portrayed. Clinicians should be equipped to steer individuals with tinnitus toward valid information.

Prevalence and relationship of olfactory dysfunction and tinnitus among middle- and old-aged population in Korea

Olfactory dysfunction and tinnitus are age-related otorhinolaryngological disorders with a high prevalence in the elderly population and share several common clinical features. However, there is no study investigating the relationship between these two diseases. We studied the prevalence of olfactory dysfunction and tinnitus among Koreans and studied the relationship between these two diseases based on the Korean National Health and Nutrition Examination Survey. The subjects of this study were enrolled from the Fifth Korean National Health and Nutrition Examination Survey (2010–2012, n = 25,534). Data of subjects aged 40 years and older who underwent physical examination and completed a self-reported questionnaire and other anthropometric variables were statistically analyzed. Odds ratios were calculated to identify the relationship between olfactory dysfunction and tinnitus, using multiple logistic regression models. Older males, non-smokers, non/lower alcohol drinker groups exhibited the relationship between olfactory dysfunction and tinnitus. Metabolic syndrome and mental health problems were associated with both olfactory dysfunction and tinnitus. After adjusting for confounding factors, olfactory dysfunction was significantly associated with tinnitus (OR 1.318). There was a dose-response relationship between tinnitus severity and the odds of olfactory dysfunction (ORs for mild, moderate and severe tinnitus were, respectively, 1.134, 1.569 and 2.044). Additional molecular genetics and animal studies are needed to determine the shared pathophysiology of the two diseases.

Changes in spontaneous movement in response to silent gaps are not robust enough to indicate the perception of tinnitus in mice

Approaches to identify the perception of tinnitus in various animal models have been difficult to apply to mouse. As a result, mice have been underutilized to investigate the cellular, molecular, and genetic mechanisms underlying tinnitus. A recent study in guinea pigs identified a novel spontaneous behavior (unconditioned response), changes in movement during silent gaps, that identified a subgroup of animals presumably with tinnitus. Guinea pigs identified with tinnitus failed to “freeze” in response to silent gaps in sound. In the hope of developing a rapid and reliable assay for mice, we used a similar approach. C57BL/6J mice underwent three trials in which spontaneous movement was video recorded in the presence of white noise interrupted with six silent gaps. Movement metrics included velocity and body movement. Before the third trial, mice underwent either sham or noise exposure to induce hearing loss and tinnitus. Auditory brainstem responses before and after noise trauma confirmed normal hearing in sham-treated animals and hearing loss in the noise-exposed cohort. No differences in the various movement metrics were detected during the silent gaps either before or after sham/noise exposure. Variability in spontaneous movement both before and after sham/noise exposure was substantially greater in mice compared to guinea pigs. Thus, this assay is not sufficiently statistically powerful to identify changes in movement that might indicate tinnitus perception in mice. Previous observations also reported increased movement overall in guinea pigs identified as suffering tinnitus. In contrast, mice showed no statistically significant differences in movement between the three trials. Despite our results, other unconditioned (as well as conditioned) behaviors should be examined in mice to test their utility to detect changes that indicate the perception of tinnitus. Such assays are essential to accelerate the use of mouse models in tinnitus research.

Pathophysiology, Diagnosis and Treatment of Somatosensory Tinnitus: A Scoping Review

Somatosensory tinnitus is a generally agreed subtype of tinnitus that is associated with activation of the somatosensory, somatomotor, and visual-motor systems. A key characteristic of somatosensory tinnitus is that is modulated by physical contact or movement. Although it seems common, its pathophysiology, assessment and treatment are not well defined. We present a scoping review on the pathophysiology, diagnosis, and treatment of somatosensory tinnitus, and identify priority directions for further research. Methods: Literature searches were conducted in Google Scholar, PubMed, and EMBASE databases. Additional broad hand searches were conducted with the additional terms etiology, diagnose, treatment. Results: Most evidence on the pathophysiology of somatosensory tinnitus suggests that somatic modulations are the result of altered or cross-modal synaptic activity within the dorsal cochlear nucleus or between the auditory nervous system and other sensory subsystems of central nervous system (e.g., visual or tactile). Presentations of somatosensory tinnitus are varied and evidence for the various approaches to treatment promising but limited. Discussion and Conclusions: Despite the apparent prevalence of somatosensory tinnitus its underlying neural processes are still not well understood. Necessary involvement of multidisciplinary teams in its diagnosis and treatment has led to a large heterogeneity of approaches whereby tinnitus improvement is often only a secondary effect. Hence there are no evidence-based clinical guidelines, and patient care is empirical rather than research-evidence-based. Somatic testing should receive further attention considering the breath of evidence on the ability of patients to modulate their tinnitus through manouvers. Specific questions for further research and review are indicated.