Chronic tinnitus resulting from head or neck injuries

Spike Analysis of the Neural Activities Across the Rats' Auditory Brain Structures

Tinnitus is a health condition that affects a large population. Clinical diagnosis and treatment have been developed for treating tinnitus for years. However, there are still limitations because researchers have yet to elucidate the mechanisms underlying how tinnitus neural signals develop in brain structures. Abnormal neural interactions among the brain areas are considered to play an important role in tinnitus generation. Researchers have been studying neural activities in the auditory brain structures, including the dorsal cochlear nucleus (DCN), inferior colliculus (IC), and auditory cortex (AC), to seek a better understanding of the information flow among these brain regions, especially in comparison with both health and tinnitus conditions. In this project, neural activities from the DCN, IC, and AC were collected and analyzed before and after the animals were noise-exposed and before and after their auditory cortices were electrically stimulated. These conditions in rats were used to estimate healthy animals, noise-trauma-induced tinnitus, and after auditory cortex electrical stimulation (ACES) treatment. The signal processing algorithms started with the raw measurement data and focused on the local field potentials (LFPs) and spikes in the time domain. The firing rate, shape of spikes, and time differences among channels were analyzed in the time domain, and phase-phase correlation was used to test the phase-frequency information. All the analysis results were summarized in plots and color-heat maps and also used to identify if any neural signal differs and cross-channel relation changes at various animal conditions and discussed.

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

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

A cross-sectional survey of non-specialist Australian audio-vestibular clinical practice for traumatic brain injury and rehabilitation

OBJECTIVE

This study explored non-specialist audiological clinical practice in the context of traumatic brain injury (TBI), and whether such practices incorporated considerations of TBI-related complexities pertaining to identification, diagnosis and management of associated auditory and vestibular disturbances.

DESIGN

A cross-sectional online survey exploring clinical practice, TBI-related training and information provision was distributed to audiologists across Australia via Audiology Australia and social media. Fifty audiologists, 80% female and 20% male, participated in this study. Years of professional practice ranged from new graduate to more than 20 years of experience.

RESULTS

Clear gaps of accuracy in knowledge and practice across all survey domains relating to the identification, diagnosis and management of patients with auditory and/or vestibular deficits following TBI were evident. Further, of the surveyed audiologists working in auditory and vestibular settings, 91% and 86%, respectively, reported not receiving professional development for the diagnosis and management of post-traumatic audio-vestibular deficits.

CONCLUSION

Inadequate resources, equipment availability and TBI-related training may have contributed to the gaps in service provision, influencing audiological management of patients with TBI. A tailored TBI approach to identification, diagnosis and management of post-traumatic auditory and vestibular disturbances is needed.

Unresolved Issues Associated with Transcranial Magnetic Stimulation (TMS) Treatment of Chronic Tinnitus

Transcranial magnetic stimulation (TMS) has been investigated as a potential treatment for chronic tinnitus for 20 years. Numerous studies have reported that repetitive TMS (rTMS) has demonstrated efficacy for reducing the severity of tinnitus and its associated co-conditions such as depression, anxiety, and insomnia. However, some researchers have reported that active rTMS is no more effective than sham (placebo) rTMS as a tinnitus treatment method. There are numerous unresolved issues in this field that need to be addressed before rTMS can become a viable treatment for tinnitus. These issues include the type or brand of TMS system and its configuration; coil type, orientation, and placement method; scalp or neural target; laterality of rTMS application; dual site vs. single site stimulation; stimulation frequency and intensity; number of sessions; number of pulses per session; determination of the resting motor threshold (rMT); characteristics of the study population and their tinnitus; and outcome measures and follow-up assessments. To address and resolve these issues, large-scale, multi-site clinical trials of rTMS for tinnitus need to be conducted to determine which rTMS protocols are the most effective. In the absence of such investigations, the issues that need to be studied and addressed remain unresolved and continue to impede the clinical application of this treatment method.

Contributions of Hearing Loss and Traumatic Brain Injury to Blast-Induced Cortical Parvalbumin Neuron Loss and Auditory Processing Deficits

Auditory processing disorder is the most common problem affecting veterans after blast exposure, but the distinct impacts of blast-related traumatic brain injury and blast-related hearing loss are unknown. Independently, both hearing loss and blast exposure affect the entire auditory processing pathway at the molecular and physiological levels. Here, we identified distinct changes to the primary auditory cortex (AI) and temporal processing in mice following blast exposure both with and without protected hearing. Our results show that blast-exposure alone activated microglia in AI, but hearing loss was required for reductions in the density of parvalbumin-expressing interneurons. Although blast exposure impaired the temporal following response, these impairments were more severe with concurrent unilateral hearing loss, further resulting in impairments in behavioral gap detection. Taken together, these results indicate that protecting hearing during blast exposure can prevent most impairments to auditory processing but does not fully protect temporal processing.

Reevaluating the Use of Sound Therapy for Tinnitus Management: Perspectives on Relevant Systematic Reviews

PURPOSE

Tinnitus is a highly prevalent condition that can severely reduce health functioning. In spite of extant clinical practice guidelines (CPGs), implementation of these CPGs is relatively uncommon. As a result, patients seeking professional services for tinnitus often have no assurance of receiving evidence-based care. The purpose of this tutorial was to clarify the evidence for sound therapy so that it may be included in future CPGs for tinnitus.

METHOD

"Best clinical evidence" is obtained from high-quality systematic reviews, which are generally considered the highest level of evidence. Our review of recent, comprehensive, high-quality systematic reviews of interventions for tinnitus concludes that cognitive behavioral therapy is the only effective intervention, though the strength of evidence was generally rated as low in these reviews. Although trials of sound therapy for tinnitus have been included in these reviews, they have been rated as having high risk of bias (RoB) and not included in syntheses or rated as insufficient strength of evidence.

RESULTS

Conclusions from these and other reviews have influenced recommendations made in CPGs for tinnitus. These conclusions, however, can make it appear that an intervention for tinnitus is not effective, even if the opposite is true. We contend that the strict inclusion criteria for these reviews are counterproductive and have the effect of obscuring decades of evidence demonstrating the clinical effectiveness of sound therapies for tinnitus. Ultimately, this process has resulted in many patients not receiving sound therapy, despite what should be sufficient evidence that this is an effective form of intervention.

CONCLUSION

If we rely on systematic reviews using contemporary RoB assessment criteria for studies published prior to these reporting guidelines, then we risk excluding important conclusions regarding interventions that could help patients in need.

Sex-Specific Prevalence, Demographic Characteristics, and Risk Factors of Tinnitus in the Hispanic Community Health Study/Study of Latinos

PURPOSE

The aim of this study was to determine the prevalence of any and chronic tinnitus among female and male individuals from varied Hispanic/Latino backgrounds and to estimate associations between risk factors for chronic tinnitus.

METHOD

Our analysis used cross-sectional baseline data collected from 2008 to 2011 from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL). Prevalence estimates and multivariable logistic regression were conducted using survey methodology. Participants included 15,768 adults (8,229 women and 7,539 men) aged 18-76 years. The primary outcome of interest was chronic tinnitus, defined as self-reported tinnitus lasting ≥ 5 min at a time and at least once per week. We hypothesized that after adjusting for covariates, the risk factors of depressed and anxious symptoms, smoking history, hypertension, and noise exposure history would be associated with higher odds of chronic tinnitus.

RESULTS

Unstratified prevalence for any tinnitus was 32.9%, and for chronic tinnitus, it was 12.1%. Sex-stratified results demonstrated that 2,995 female individuals (36.4%) and 2,187 male individuals (29.0%) reported any tinnitus, and of these, 1,043 female individuals (12.7%) and 870 male individuals (11.5%) reported chronic tinnitus. In the fully adjusted model, depressed and anxious symptoms as well as recreational noise exposure were associated with higher odds of chronic tinnitus in female individuals (odds ratios [ORs] = 1.06, confidence interval [CI; 1.04, 1.07]; 1.02, CI [1.01, 1.04]; and 1.40, CI [1.20, 1.62]) and in male individuals (ORs = 1.06, CI [1.03, 1.08]; 1.05, CI [1.02, 1.08]; and 1.30, CI [1.05, 1.65]). Current smoking was a risk factor for chronic tinnitus in male individuals (OR = 1.53, CI [1.16, 2.02]).

CONCLUSIONS

Prevalence of any and chronic tinnitus in the HCHS/SOL baseline cohort is higher than that reported in previous studies, particularly among female individuals. Understanding risk factors associated with tinnitus is important for the development of culturally and linguistically appropriate public health programs that consider sex differences and promote lifestyle modifications known to lower the odds of experiencing tinnitus.

Effectiveness of Dry Needling in Bothersome Chronic Tinnitus in Patients with Myofascial Trigger Points

Introduction  Therapeutic dry needling (DN) is effective in reducing the discomfort of chronic somatosensory tinnitus in patients with myofascial trigger points (MTP)s.

Objective  To evaluate the efficacy of DN in chronic somatosensory tinnitus discomfort in patients with MTP.

Methods  Placebo-controlled paired trial that included 16 patients with a diagnosis of somatosensory chronic tinnitus and with the presence of at least one active or latent MTP. Treatment was performed in two phases: (1) four sessions (one session per week for four consecutive weeks) of placebo DN and (2) four sessions of therapeutic DN with a gap (washout) of 15 days between these phases.

Results  The Tinnitus Handicap Inventory (THI) variable and its emotional domain had a statistically significant reduction in therapeutic DN when compared with placebo DN ( p  = 0.024 and p = 0.011, respectively).

The tinnitus visual analogic scale (VAS) signaled a reduction in tinnitus discomfort when compared with moments before and after therapeutic DN ( p  < 0.05).

Conclusion  The therapeutic DN technique for MTP in patients with chronic tinnitus of somatosensory origin proved effective in reducing symptom discomfort, as measured by the THI (total score) and its emotional domain when compared with placebo DN.

Trigeminal Contributions to the Dorsal Cochlear Nucleus in Mouse

The dorsal cochlear nucleus (DCN) is the first site of multisensory integration in the auditory pathway of mammals. The DCN circuit integrates non-auditory information, such as head and ear position, with auditory signals, and this convergence may contribute to the ability to localize sound sources or to suppress perceptions of self-generated sounds. Several extrinsic sources of these non-auditory signals have been described in various species, and among these are first- and second-order trigeminal axonal projections. Trigeminal sensory signals from the face and ears could provide the non-auditory information that the DCN requires for its role in sound source localization and cancelation of self-generated sounds, for example, head and ear position or mouth movements that could predict the production of chewing or licking sounds. There is evidence for these axonal projections in guinea pigs and rats, although the size of the pathway is smaller than might be expected for a function essential for a prey animals’ survival. However, evidence for these projections in mice, an increasingly important species in auditory neuroscience, is lacking, raising questions about the universality of such proposed functions. We therefore investigated the presence of trigeminal projections to the DCN in mice, using viral and transgenic approaches. We found that the spinal trigeminal nucleus indeed projects to DCN, targeting granule cells and unipolar brush cells. However, direct axonal projections from the trigeminal ganglion itself were undetectable. Thus, secondary brainstem sources carry non-auditory signals to the DCN in mice that could provide a processed trigeminal signal to the DCN, but primary trigeminal afferents are not integrated directly by DCN.

Prevalence of Self-Reported Depression Symptoms and Perceived Anxiety Among Community-Dwelling U.S. Adults Reporting Tinnitus

Purpose

The aim of this study was to examine the relationship between tinnitus and self-reported mental health distress, namely, depression symptoms and perceived anxiety, in adults who participated in the National Health and Nutrition Examinations Survey between 2009 and 2012. A secondary aim was to determine if a history of serving in the military modified the associations between tinnitus and mental health distress.

Method

This was a cross-sectional study design of a national data set that included 5,550 U.S. community-dwelling adults ages 20 years and older, 12.7% of whom were military Veterans. Bivariable and multivariable logistic regression was used to estimate the association between tinnitus and mental health distress. All measures were based on self-report. Tinnitus and perceived anxiety were each assessed using a single question. Depression symptoms were assessed using the Patient Health Questionnaire, a validated questionnaire. Multivariable regression models were adjusted for key demographic and health factors, including self-reported hearing ability.

Results

Prevalence of tinnitus was 15%. Compared to adults without tinnitus, adults with tinnitus had a 1.8-fold increase in depression symptoms and a 1.5-fold increase in perceived anxiety after adjusting for potential confounders. Military Veteran status did not modify these observed associations.

Conclusions

Findings revealed an association between tinnitus and both depression symptoms and perceived anxiety, independent of potential confounders, among both Veterans and non-Veterans. These results suggest, on a population level, that individuals with tinnitus have a greater burden of perceived mental health distress and may benefit from interdisciplinary health care, self-help, and community-based interventions.

Supplemental Material

https://doi.org/10.23641/asha.12568475

Increased risk of tinnitus following a trigeminal neuralgia diagnosis: a one-year follow-up study

Background

Tinnitus due to hyperactivity across neuronal ensembles along the auditory pathway is reported. We hypothesized that trigeminal neuralgia patients may subsequently suffer from tinnitus. Using nationwide, population-based data and a retrospective cohort study design, we investigated the risk of tinnitus within 1 year following trigeminal neuralgia.

Methods

We used the Taiwan National Health Insurance Research Dataset, a claims database, to identify all patients diagnosed with trigeminal neuralgia from January 2001 to December 2014, 12,587 patients. From the remaining patients, we identified 12,587 comparison patients without trigeminal neuralgia by propensity score matching, using sex, age, monthly income, geographic region, residential urbanization level, and tinnitus-relevant comorbidities (hyperlipidemia, diabetes, coronary heart disease, hypertension, cervical spondylosis, temporomandibular joint disorders and injury to head and neck and index year). All study patients (n = 25,174) were tracked for a one-year period to identify those with a subsequent diagnosis of tinnitus over 1-year follow-up.

Results

Among total 25,174 sample patients, the incidence of tinnitus was 18.21 per 100 person-years (95% CI = 17.66 ~ 18.77), the rate being 23.57 (95% CI = 22.68 ~ 24.49) among patients with trigeminal neuralgia and 13.17 (95% CI = 12.53 ~ 13.84) among comparison patients. Furthermore, the adjusted Cox proportional hazard ratio for tinnitus in the trigeminal neuralgia group was 1.68 (95% CI = 1.58 ~ 1.80) relative to the comparison cohort.

Conclusions

We found a significantly increased risk of tinnitus within 1 year of trigeminal neuralgia diagnosis compared to those without the diagnosis. Further studies in other countries and ethnicities are needed to explore the relationship between trigeminal neuralgia and subsequent tinnitus.

The Experience of Tinnitus and Its Interaction With Unique Life Histories-Life Events, Trauma and Inner Resources Narrated by Patients With Tinnitus

Background: The challenges facing people with chronic tinnitus include finding relief and rebuilding quality of life. However, previous traumatic episodes may influence adjustment and prolong suffering. Recovery implies reducing aggravating reactions and improving social roles, relationships and interests. Self-narratives about living with tinnitus have not yet received the attention they deserve in the research literature. Thus, the main goal of the present study was to illustrate how tinnitus suffering interacts with the participants' unique life histories. Method: Four women and one man (ages 52-58) took part in the study after consulting a special hearing clinic for annoying tinnitus. Criteria for inclusion were that tinnitus was regarded as a problem with negative consequences for quality of life. The participants should be willing to share how the experience of tinnitus suffering interacts with their previous life story. Narrative methodology was employed in order to achieve the goals of the study. We used unstructured interviews with free conversation, which allowed for rich narratives with full contextual meaning. Results: The findings, based on the narrative analysis, revealed that three out of five participants presented a regressive form of narrative indicating ongoing struggles beyond tinnitus itself, which they were unable to bring to closure. For them, valued goals were continuously thwarted by frustrating circumstances in their lives, either past events or current unresolved issues. Progressive and stable narratives, as identified in the other two participants, demonstrated values that rely on others' attitude and understanding toward their suffering, in sharp contrast to the regressive narratives. We suggest that a central issue in tinnitus rehabilitation should be to help suffering patients to overcome unresolved conflicts and thereby extend their ability for a fuller commitment in life. Conclusion: Considering enduring tinnitus as a chronic condition, whose course is likely to vary depending on the patient's general health status, an alteration of progressive and stable narratives is likely to occur during the lifespan. A progressive narrative shows similarities to the core construct of the salutogenesis model of health promotion (1). In conclusion, a narrative approach in tinnitus rehabilitation can be health promoting by offering the patient the opportunity to engage in storytelling, which in turn can increase comprehensibility and a sense of coherence.

A study on the epidemiology of tinnitus in the United Kingdom

Purpose

Subjective tinnitus is a common symptom with potentially negative impact on quality of life. More research is required to gain a deeper understanding of the disease and its clinical presentation. To estimate the incidence of tinnitus and to describe patient-related characteristics such as lifestyle factors and comorbidities.

Patients and methods

Using the Clinical Practice Research Datalink, we calculated incidence rates of first-time diagnosed tinnitus in an adult population between 2000 and 2016. We stratified incidence rates by sex, age, and year of diagnosis. Additionally, we performed a 1:1 matched case-control study comparing body mass index, lifestyle factors and selected comorbidities between patients with incident tinnitus and tinnitus-free controls.

Results

We identified 109 783 adults with a first-time diagnosis of tinnitus between 2000 and 2016, yielding an overall age-standardized incidence rate of 25.0 new tinnitus cases per 10,000 person-years (95% CI: 24.6–25.5). There was a steady increase in tinnitus incidence throughout the study period. Approximately 80% of tinnitus cases were diagnosed at age 40 years or older. We observed the highest incidence rate in individuals aged 60–69 years (41.2 per 10,000 person-years, 95% CI: 40.7–41.7). Smokers and alcohol drinkers were at lower risk of being diagnosed with tinnitus compared with non-smokers and non-drinkers, respectively. The occurrence of tinnitus was strongly associated with a recent diagnosis of several otological and vestibular disorders as well as head and neck disorders.

Conclusion

The present observational study found an increasing incidence of tinnitus over time, emphasizing the continuously growing health burden. The findings on patient characteristics, lifestyle factors, and selected comorbidities contribute to a better understanding of risk factors for tinnitus.

Auditory and Cognitive Behavioral Performance Deficits and Symptom Reporting in Postconcussion Syndrome Following Mild Traumatic Brain Injury

Purpose This study examined auditory deficits and symptom reporting in individuals with long-term postconcussion symptoms following a single mild traumatic brain injury (mTBI) compared to age- and gender-matched controls without a history of mTBI. Method Case history interviews, symptom questionnaires, and a battery of central auditory and neuropsychological tests were administered to 2 groups. The mTBI group was a civilian population recruited from a local concussion management program who were seeking rehabilitation for postconcussion-related problems in a postacute period between 3 and 18 months following injury. Symptom validity testing was included to assess the rate of possible insufficient test effort and its influence on scores for all outcome measures. Analyses of group differences in test scores were performed both with and without the participants who showed insufficient test effort. Rates of symptom reporting, correlations among symptoms and behavioral test outcomes, and the relationships between auditory and cognitive test performance were analyzed. Results The mTBI group reported a high rate of auditory symptoms and general postconcussion symptoms. Performance on neuropsychological tests of cognitive function showed some differences in raw scores between groups, but when effort was considered, there were no significant differences in the rate of abnormal performance between groups. In contrast, there were significant differences in both raw scores and the rate of abnormal performance between groups for some auditory tests when only considering participants with sufficient effort. Auditory symptoms were strongly correlated with other general postconcussion symptoms. Conclusions Significant auditory symptoms and evidence of long-term central auditory dysfunction were found in a subset of individuals who had chronic postconcussion symptoms after a single mTBI unrelated to blast trauma. The rate of abnormal performance on auditory behavioral tests exceeded the rate of abnormal performance on tests of cognitive function. Supplemental Material https://doi.org/10.23641/asha.8329955.

The Role of the Brainstem in Generating and Modulating Tinnitus

Purpose The purpose of this work is to present a perspective article summarizing ideas pertaining to the brainstem's role in generating and modulating tinnitus. It is organized in 4 sections: Part 1, the role of the brainstem as a tinnitus generator; Part 2, the role of the brainstem in modulating tinnitus; Part 3, the role of the brainstem in nonauditory comorbid conditions associated with tinnitus; and Part 4, clinical implications. In Part 1, well-established neurophysiological models are discussed providing the framework of evidence that auditory brainstem nuclei play a role in generating tinnitus. In Part 2, ideas are presented explaining modulatory effects on tinnitus related to underlying pathways originating from or projecting to brainstem auditory and nonauditory nuclei. This section addresses multiple phenomena including somatic-related, attention-mediated, and emotion-mediated changes in the tinnitus percept. In Part 3, the role of the brainstem in common nonauditory comorbidities that occur in patients with tinnitus is discussed. Part 4 presents clinical implications of these new ideas related to the brainstem's involvement in generating and modulating tinnitus. Impact Knowledge of the brainstem's involvement in generating and modulating tinnitus provides a context for health care professionals to understand the temporal relationship between tinnitus and common nonauditory comorbid conditions.

Prolonged Exposure of CBA/Ca Mice to Moderately Loud Noise Can Cause Cochlear Synaptopathy but Not Tinnitus or Hyperacusis as Assessed With the Acoustic Startle Reflex

Hearing loss changes the auditory brain, sometimes maladaptively. When deprived of cochlear input, central auditory neurons become more active spontaneously and begin to respond more strongly and synchronously to better preserved sound frequencies. This spontaneous and sound-evoked central hyperactivity has been postulated to trigger tinnitus and hyperacusis, respectively. Localized hyperactivity has also been observed after long-term exposure to noise levels that do not damage the cochlea. Adult animals exposed to bands of nondamaging noise exhibited suppressed spontaneous and sound-evoked activity in the area of primary auditory cortex (A1) stimulated by the exposure band but had increased spontaneous and evoked activity in neighboring A1 areas. We hypothesized that the cortically suppressed frequencies should for some time after exposure be perceived as less loud than before (hypoacusis), whereas the hyperactivity outside of the exposure band might lead to frequency-specific hyperacusis or tinnitus. To investigate this, adult CBA/Ca mice were exposed for >2 months to 8 to 16 kHz noise at 70 or 75 dB sound pressure level and tested for hypo-/hyperacusis and tinnitus using tone and gap prepulse inhibition of the acoustic startle reflex. Auditory brainstem responses and distortion product otoacoustic emissions showed evidence of cochlear synaptopathy after exposure at 75 but not 70 dB, putting a lower bound on damaging noise levels for CBA/Ca mice. Contrary to hypothesis, neither exposure significantly shifted startle results from baseline. These negative findings nevertheless have implications for startle test methodology and for the putative role of central hyperactivity in hyperacusis and tinnitus.

Cofactors of Pediatric Tinnitus: A Look at the Whole Picture

Retrospective chart review of 248 children (1-19 years old) with tinnitus who presented to a tertiary pediatric hospital between 2006 and 2011, looking at which cofactors are predictors of pediatric tinnitus. In our review, we extracted demographics, symptoms, historical data, imaging, and laboratory results; we compared with the general population. Eighty-seven percent had normal hearing. Age distribution, noise exposure, and frequency of psychiatric diagnoses in our cohort were consistent with previous reports. We found a lower incidence of otitis media and the same prevalence of dizziness, asthma, and hearing loss as the general population, a lower prevalence of Eustachian tube dysfunction, otitis media, headaches, and higher incidence of rhinosinusitis. Lack of patient reporting and objective testing complicate the ability to detect pediatric tinnitus. We revealed a gap in the literature regarding rhinosinusitis as a cofactor, imaging during diagnosis, and if psychiatric diagnoses are associated with tinnitus in younger children.

Telephone-Based Progressive Tinnitus Management for Persons With and Without Traumatic Brain Injury: A Randomized Controlled Trial

OBJECTIVES

This randomized controlled trial evaluated the efficacy of delivering coping skills education from Progressive Tinnitus Management (PTM) by telephone (Tele-PTM). The trial followed a previous pilot study that showed positive results for Tele-PTM.

DESIGN

Participants included individuals with bothersome tinnitus (N = 205) located anywhere within the United States. A special emphasis was given to including individuals who had experienced one or more traumatic brain injuries (TBIs). Participants were randomized to either Tele-PTM intervention or 6-month wait-list control (WLC). The Tele-PTM intervention involved five telephone appointments-two led by an audiologist (teaching how to use therapeutic sound) and three by a psychologist (teaching coping skills derived from cognitive-behavioral therapy). It was hypothesized that Tele-PTM would be more effective than WLC in reducing functional effects of tinnitus as measured with the Tinnitus Functional Index. Additional outcome measures included the Self-Efficacy for Managing Reactions to Tinnitus questionnaire and the Hospital Anxiety and Depression Scale. The effect of Tele-PTM on outcomes was estimated using linear mixed models.

RESULTS

Overall results showed convincingly that the Tele-PTM group had significantly better outcomes than the WLC group. These results were consistent across all outcome measures, indicating not only a reduction of tinnitus functional distress but also increased self-efficacy. Improvements in measures of anxiety and depression were also observed. Tele-PTM participants in all TBI categories showed significant improvement.

CONCLUSIONS

Results provide strong support for use of Tele-PTM methodology for persons with bothersome tinnitus, regardless of whether the person also has TBI symptoms. The effect size for Tele-PTM was high for the primary outcome measure, the Tinnitus Functional Index, and all other outcome measures showed significant improvement. Combined with our previous pilot study, the Tele-PTM method is validated for potential nationwide provision of tinnitus services.

Association Between Subjective Tinnitus and Cervical Spine or Temporomandibular Disorders: A Systematic Review

Movements of the neck and jaw may modulate the loudness and pitch of tinnitus. The aim of the present study was to systematically analyze the strength of associations between subjective tinnitus, cervical spine disorders (CSD), and temporomandibular disorders (TMD). A systematic literature search of the Medline, Embase, and Pedro databases was carried out on articles published up to September 2017. This covered studies in which tinnitus and CSD or TMD were studied as a primary or a secondary outcome and in which outcomes were compared with a control group. Included articles were evaluated on nine methodological quality criteria. Associations between tinnitus and CSD or TMD were expressed as odds ratios. In total, 2,139 articles were identified, of which 24 studies met the inclusion criteria. Twice, two studies were based on the same data set; consequently, 22 studies were included in the meta-analysis. Methodological quality was generally limited by a lack of blinding, comparability of groups, and nonvalidated instruments for assessing CSD. Results indicated that patients with tinnitus more frequently reported CSD than subjects without tinnitus. The odds ratio was 2.6 (95% CI [1.1, 6.4]). For TMD, a bidirectional association with tinnitus was found; odds ratios ranged from 2.3 (95%CI [1.5, 3.6]) for arthrogenous TMD to 6.7 (95%CI [2.4, 18.8]) for unspecified TMD. Funnel plots suggested a publication bias. After adjusting for this, the odds ratios decreased, but associations persisted. There is weak evidence for an association between subjective tinnitus and CSD and a bidirectional association between tinnitus and TMD.

Sensory neurologic disorders: Tinnitus

Tinnitus is the sensation of hearing a sound with no external auditory stimulus present. It is a public health issue correlated with multiple comorbidities and precipitating factors such as noise exposure, military service, and traumatic brain injury, migraine, insomnia, small vessel disease, smoking history, stress exposure, anxiety, depression, and socioeconomic status. Clinical experience and a recent literature review point at tinnitus as a neuropsychiatric condition involving both auditory and nonauditory cortical areas of the brain and affecting brain-auditory circuitry. In fact, brain-ear connections have been highlighted in different models. Forward management of this disorder should take this body of research into consideration as tinnitus remains a challenging condition to evaluate and treat with current management protocols still symptomatic at best. With a better understanding of the etiologic factors and comorbidities of tinnitus, additional research trials and new therapeutic approaches could see the light to tackle this public health disability bringing hope to patients and doctors.

Blast Exposure Disrupts the Tonotopic Frequency Map in the Primary Auditory Cortex

Blast exposure can cause various auditory disorders including tinnitus, hyperacusis, and other central auditory processing disorders. While this is suggestive of pathologies in the central auditory system, the impact of blast exposure on central auditory processing remains poorly understood. Here we examined the effects of blast shockwaves on acoustic response properties and the tonotopic frequency map in the auditory cortex. We found that multiunits recorded from the auditory cortex exhibited higher acoustic thresholds and broader frequency tuning in blast-exposed animals. Furthermore, the frequency map in the primary auditory cortex was distorted. These changes may contribute to central auditory processing disorders.

Auditory-somatosensory bimodal stimulation desynchronizes brain circuitry to reduce tinnitus in guinea pigs and humans

The dorsal cochlear nucleus is the first site of multisensory convergence in mammalian auditory pathways. Principal output neurons, the fusiform cells, integrate auditory nerve inputs from the cochlea with somatosensory inputs from the head and neck. In previous work, we developed a guinea pig model of tinnitus induced by noise exposure and showed that the fusiform cells in these animals exhibited increased spontaneous activity and cross-unit synchrony, which are physiological correlates of tinnitus. We delivered repeated bimodal auditory-somatosensory stimulation to the dorsal cochlear nucleus of guinea pigs with tinnitus, choosing a stimulus interval known to induce long-term depression (LTD). Twenty minutes per day of LTD-inducing bimodal (but not unimodal) stimulation reduced physiological and behavioral evidence of tinnitus in the guinea pigs after 25 days. Next, we applied the same bimodal treatment to 20 human subjects with tinnitus using a double-blinded, sham-controlled, crossover study. Twenty-eight days of LTD-inducing bimodal stimulation reduced tinnitus loudness and intrusiveness. Unimodal auditory stimulation did not deliver either benefit. Bimodal auditory-somatosensory stimulation that induces LTD in the dorsal cochlear nucleus may hold promise for suppressing chronic tinnitus, which reduces quality of life for millions of tinnitus sufferers worldwide.

The Application of the International Classification of Functioning, Disability and Health to Functional Auditory Consequences of Mild Traumatic Brain Injury

This article reviews the auditory consequences of mild traumatic brain injury (mTBI) within the context of the International Classification of Functioning, Disability and Health (ICF). Because of growing awareness of mTBI as a public health concern and the diverse and heterogeneous nature of the individual consequences, it is important to provide audiologists and other health care providers with a better understanding of potential implications in the assessment of levels of function and disability for individual interdisciplinary remediation planning. In consideration of body structures and function, the mechanisms of injury that may result in peripheral or central auditory dysfunction in mTBI are reviewed, along with a broader scope of effects of injury to the brain. The activity limitations and participation restrictions that may affect assessment and management in the context of an individual's personal factors and their environment are considered. Finally, a review of management strategies for mTBI from an audiological perspective as part of a multidisciplinary team is included.

Risk of Ear-Associated Diseases After Zygomaticomaxillary Complex Fracture

PURPOSE

Investigate the risk of ear-associated diseases after zygomaticomaxillary complex (ZMC) fracture in a population-based retrospective cohort study.

MATERIALS AND METHODS

This is a retrospective cohort study using Taiwan's National Health Insurance Research Database of reimbursement claims. A total of 1,330 ZMC fracture patients and 5,320 non-ZMC fracture participants were included and newly developed ear-associated disease data were collected. A Poisson regression and multivariate Cox proportion hazard regression were used for data analysis.

RESULTS

The ZMC fracture cohort had a higher incidence of tinnitus than non-ZMC fracture cohort (IRR 1.64, 95 % CI 1.37-1.96), particularly in younger patients (≤34 years of age; IRR 4.05, 95 % CI 3.18-5.15) and male patients (IRR 2.08, 95 % CI 1.12-3.73). ZMC fracture patients also showed a significantly increased risk of having trigeminal neuralgia [IRR 4.06, 95 % CI 3.34-4.94, adjusted HR 4.07 (1.02-16.3)]. For sudden hearing loss and peripheral vertigo, the incidence densities were higher in the ZMC fracture cohort, but these relationships were not significant in the multivariate Cox proportional hazard regression analyses (HR 2.69, 95 % CI 0.76-9.53 for risk of sudden hearing loss; HR 1.36, 95 % CI 0.77-2.40 for risk of peripheral vertigo).

CONCLUSIONS

The findings of the study suggest an increased risk of ear-associated diseases among individuals with ZMC fractures, particularly within 2-years follow-ups after injury. We suggest performing detailed examinations for ear-associated diseases in patients with ZMC fractures for early diagnosis and adequate treatment.

Tinnitus: Maladaptive auditory-somatosensory plasticity

Tinnitus, the phantom perception of sound, is physiologically characterized by an increase in spontaneous neural activity in the central auditory system. However, as tinnitus is often associated with hearing impairment, it is unclear how a decrease of afferent drive can result in central hyperactivity. In this review, we first assess methods for tinnitus induction and objective measures of the tinnitus percept in animal models. From animal studies, we discuss evidence that tinnitus originates in the cochlear nucleus (CN), and hypothesize mechanisms whereby hyperactivity may develop in the CN after peripheral auditory nerve damage. We elaborate how this process is likely mediated by plasticity of auditory-somatosensory integration in the CN: the circuitry in normal circumstances maintains a balance of auditory and somatosensory activities, and loss of auditory inputs alters the balance of auditory somatosensory integration in a stimulus timing dependent manner, which propels the circuit towards hyperactivity. Understanding the mechanisms underlying tinnitus generation is essential for its prevention and treatment. This article is part of a Special Issue entitled <Tinnitus>.

Undetected metallic chopstick stabbed on neck resulting tinnitus and foreign body sensation

Penetrating neck injuries constitute 5-10% of all trauma cases. These injuries may cause life-threatening suppurative or vascular complications, but the severity and extent of damage depends upon the inflicting object and the involved structures. If significant complications are not expected, then it is best to leave the foreign body embedded and avoid surgical risks. We present a rare case of a foreign body embedded in the neck causing tinnitus and foreign body sensation.

Non-Invasive Brain Stimulation for the Treatment of Symptoms Following Traumatic Brain Injury

BACKGROUND

Traumatic brain injury (TBI) is a common cause of physical, psychological, and cognitive impairment, but many current treatments for TBI are ineffective or produce adverse side effects. Non-invasive methods of brain stimulation could help ameliorate some common trauma-induced symptoms.

OBJECTIVE

This review summarizes instances in which repetitive Transcranial Magnetic Stimulation (rTMS) and transcranial Direct Current Stimulation (tDCS) have been used to treat symptoms following a TBI. A subsequent discussion attempts to determine the value of these methods in light of their potential risks.

METHODS

The research databases of PubMed/MEDLINE and PsycINFO were electronically searched using terms relevant to the use of rTMS and tDCS as a tool to decrease symptoms in the context of rehabilitation post-TBI.

RESULTS

Eight case-studies and four multi-subject reports using rTMS and six multi--subject studies using tDCS were found. Two instances of seizure are discussed.

CONCLUSION

There is evidence that rTMS can be an effective treatment option for some post-TBI symptoms, such as depression, tinnitus, and neglect. Although the safety of this method remains uncertain, the use of rTMS in cases of mild TBI without obvious structural damage may be justified. Evidence on the effectiveness of tDCS is mixed, highlighting the need for additional investigations.

The neuropsychiatry of tinnitus: a circuit-based approach to the causes and treatments available

Patients presenting with tinnitus commonly have neuropsychiatric symptoms with which physicians need to be familiar. We provide an overview of tinnitus, including its types and pathophysiology. We discuss how recent methods such as transcranial magnetic stimulation, positron emission tomography, MRI, magnetoencephalography and quantitative EEG improve our understanding of the pathophysiology of tinnitus and connect tinnitus to the neuropsychiatric symptoms. We then explain why treatment of the tinnitus patient falls within the purview of neuropsychiatry. Psychiatric problems such as depression, anxiety and personality disorders are discussed. We also discuss how stress, headache, cognitive processing speed and sleep disturbance are associated with tinnitus. Finally, we provide a brief overview of treatment options and discuss the efficacy of various medications, including benzodiazepines, antidepressants, antipsychotics and mood-stabilising agents, and various non-pharmacological treatment options, such as cognitive behavioural therapy, habituation therapy and acupuncture. We also discuss how brain stimulation therapies are being developed for the treatment of tinnitus. In conclusion, a review of the literature demonstrates the varied neuropsychiatric manifestations of tinnitus. Imaging studies help to explain the mechanism of the association. However, more research is needed to elucidate the neurocircuitry underlying the association.

Mining and analysis of audiology data to find significant factors associated with tinnitus masker

Objectives

The objective of this research is to find the factors associated with tinnitus masker from the literature, and by using the large amount of audiology data available from a large NHS (National Health Services, UK) hearing aid clinic. The factors evaluated were hearing impairment, age, gender, hearing aid type, mould and clinical comments.

Design

The research includes literature survey for factors associated with tinnitus masker, and performs the analysis of audiology data using statistical and data mining techniques.

Setting

This research uses a large audiology data but it also faced the problem of limited data for tinnitus.

Participants

It uses 1,316 records for tinnitus and other diagnoses, and 10,437 records of clinical comments from a hearing aid clinic.

Primary and secondary outcome measures

The research is looking for variables associated with tinnitus masker, and in future, these variables can be combined into a single model to develop a decision support system to predict about tinnitus masker for a patient.

Results

The results demonstrated that tinnitus maskers are more likely to be fit to individuals with milder forms of hearing loss, and the factors age, gender, type of hearing aid and mould were all found significantly associated with tinnitus masker. In particular, those patients having Age < =55 years were more likely to wear a tinnitus masker, as well as those with milder forms of hearing loss. ITE (in the ear) hearing aids were also found associated with tinnitus masker. A feedback on the results of association of mould with tinnitus masker from a professional audiologist of a large NHS (National Health Services, UK) was also taken to better understand them. The results were obtained with different accuracy for different techniques. For example, the chi-squared test results were obtained with 95% accuracy, for Support and Confidence only those results were retained which had more than 1% Support and 80% Confidence.

Conclusions

The variables audiograms, age, gender, hearing aid type and mould were found associated with the choice of tinnitus masker in the literature and by using statistical and data mining techniques. The further work in this research would lead to the development of a decision support system for tinnitus masker with an explanation that how that decision was obtained.

Trauma-associated tinnitus: audiological, demographic and clinical characteristics

Background

Tinnitus can result from different etiologies. Frequently, patients report the development of tinnitus after traumatic injuries. However, to which extent this specific etiologic factor plays a role for the phenomenology of tinnitus is still incompletely understood. Additionally, it remains a matter of debate whether the etiology of tinnitus constitutes a relevant criterion for defining tinnitus subtypes.

Objective

By investigating a worldwide sample of tinnitus patients derived from the Tinnitus Research Initiative (TRI) Database, we aimed to identify differences in demographic, clinical and audiological characteristics between tinnitus patients with and without preceding trauma.

Materials

A total of 1,604 patients were investigated. Assessment included demographic data, tinnitus related clinical data, audiological data, the Tinnitus Handicap Inventory, the Tinnitus Questionnaire, the Beck Depression Inventory, various numeric tinnitus rating scales, and the World Health Organisation Quality of Life Scale (WHOQoL).

Results

Our data clearly indicate differences between tinnitus patients with and without trauma at tinnitus onset. Patients suffering from trauma-associated tinnitus suffer from a higher mental burden than tinnitus patients presenting with phantom perceptions based on other or unknown etiologic factors. This is especially the case for patients with whiplash and head trauma. Patients with posttraumatic noise-related tinnitus experience more frequently hyperacousis, were younger, had longer tinnitus duration, and were more frequently of male gender.

Conclusions

Trauma before tinnitus onset seems to represent a relevant criterion for subtypization of tinnitus. Patients with posttraumatic tinnitus may require specific diagnostic and therapeutic management. A more systematic and – at best - standardized assessment for hearing related sequelae of trauma is needed for a better understanding of the underlying pathophysiology and for developing more tailored treatment approaches as well.

Role of acamprosate in sensorineural tinnitus

Acamprosate with dual mechanism of action as glutamate antagonist and GABA agonist can be a potential target to decrease the severity of sensorineural tinnitus.

The distressed brain: a group blind source separation analysis on tinnitus

BACKGROUND

Tinnitus, the perception of a sound without an external sound source, can lead to variable amounts of distress.

METHODOLOGY

In a group of tinnitus patients with variable amounts of tinnitus related distress, as measured by the Tinnitus Questionnaire (TQ), an electroencephalography (EEG) is performed, evaluating the patients' resting state electrical brain activity. This resting state electrical activity is compared with a control group and between patients with low (N = 30) and high distress (N = 25). The groups are homogeneous for tinnitus type, tinnitus duration or tinnitus laterality. A group blind source separation (BSS) analysis is performed using a large normative sample (N = 84), generating seven normative components to which high and low tinnitus patients are compared. A correlation analysis of the obtained normative components' relative power and distress is performed. Furthermore, the functional connectivity as reflected by lagged phase synchronization is analyzed between the brain areas defined by the components. Finally, a group BSS analysis on the Tinnitus group as a whole is performed.

CONCLUSIONS

Tinnitus can be characterized by at least four BSS components, two of which are posterior cingulate based, one based on the subgenual anterior cingulate and one based on the parahippocampus. Only the subgenual component correlates with distress. When performed on a normative sample, group BSS reveals that distress is characterized by two anterior cingulate based components. Spectral analysis of these components demonstrates that distress in tinnitus is related to alpha and beta changes in a network consisting of the subgenual anterior cingulate cortex extending to the pregenual and dorsal anterior cingulate cortex as well as the ventromedial prefrontal cortex/orbitofrontal cortex, insula, and parahippocampus. This network overlaps partially with brain areas implicated in distress in patients suffering from pain, functional somatic syndromes and posttraumatic stress disorder, and might therefore represent a specific distress network.

Tinnitus and depression

OBJECTIVES

Depressive symptoms are common in individuals with tinnitus and may substantially aggravate their distress. The mechanisms, however, by which depression and tinnitus mutually interact are still not fully understood.

METHODS

Here we review neurobiological knowledge relevant for the interplay between depression and tinnitus.

RESULTS

Neuroimaging studies confirm the existence of neural circuits that are activated both in depression and tinnitus. Studies of neuroendocrine function demonstrate alterations of the HPA-axis in depression and, more recently, in tinnitus. Studies addressing neurotransmission suggest that the dorsal cochlear nucleus that is typically hyperactive in tinnitus, is also involved in the control of attention and emotional responses via projections to the locus coeruleus, the reticular formation and the raphe nuclei. Impaired hippocampal neurogenesis has been documented in animals with tinnitus after noise trauma, as in animal models of depression. Finally, from investigations of human candidate genes, there is some evidence to suggest that variant BDNF may act as a common susceptibility factor in both disorders.

CONCLUSIONS

These parallels in the pathophysiology of tinnitus and depression argue against comorbidity by chance and against depression as pure reaction on tinnitus. Instead, they stand for a complex interplay between tinnitus and depression. Implications for tinnitus treatment are discussed.

Chronic Tinnitus following Electroconvulsive Therapy

A 43-year-old female with a 27-year history of obsessive-compulsive disorder and major depression had previously been treated with psychotherapy, antidepressant, and antipsychotic medications. Because these treatments were minimally effective and because the frequency and duration of her depressive episodes continued to increase, the patient was scheduled to undergo a series of electroconvulsive therapy (ECT) procedures. The patient received four ECT treatments during one month. Stimulating current was delivered to the right frontotemporal region of the head. Electroencephalographic seizures occurred during each of the ECT procedures. After the patient recovered from anesthesia, she complained of headaches, muscle pain, amnesia, and, after the fourth ECT, she reported a ringing sound in her right ear. Audiometric testing the day after the fourth ECT revealed a slight increase in threshold for 8000 Hz tones in her right ear. It is likely that current delivered during the fourth ECT treatment triggered the perception of tinnitus for this patient. The unique organization of this patient's central nervous and auditory systems combined with her particular pharmacological history might have predisposed her to developing tinnitus.

‘‘Ringing in the Ears’’: Narrative Review of Tinnitus and Its Impact

About 10% of the population experiences tinnitus, a common and distressing symptom characterized by the perception of sound in the absence of external stimuli. There is, however, marked heterogeneity in etiology, perception, and extent of distress among those who experience tinnitus. Reactions to tinnitus vary from simple awareness to severe irritation; some people have difficulty in hearing because of the loudness of the noise. Severe tinnitus causes many, often psychological, symptoms (e.g., tension, frustration, impaired concentration, disrupted sleep). For some, tinnitus is temporary, for others it is longstanding. Although many people adjust successfully, others are disabled by tinnitus; approximately 5% experience persistent and severe symptoms affecting their lifestyle and significantly reducing their quality of life. Because tinnitus is poorly understood and no single therapeutic approach is effective for all patients, many patients are told that ‘‘nothing can be done’’ and they must ‘‘learn to live with it.’’ In spite of these challenges, there is remarkably little relevant nursing literature on tinnitus. This literature review was conducted to explore current knowledge of tinnitus, including prevalence, causes and diagnosis, and assessment. Its psychosocial effects and impact on individuals are considered. Implications for practice are discussed—demonstrating that understanding the full impact of the condition and identifying patients’ needs are essential to effective care.

The Tinnitus Research Initiative (TRI) database: a new approach for delineation of tinnitus subtypes and generation of predictors for treatment outcome

Tinnitus, the phantom perception of sound, is a frequent disorder that causes significant morbidity and treatment is elusive. A large variety of different treatment options have been proposed and from most of them some patients benefit. However, a particular treatment that helps one patient may fail for others. This suggests that there are different forms of tinnitus which differ in their pathophysiology and their response to specific treatments. Therefore, it is a major challenge for tinnitus treatment to identify the most promising therapy for a specific patient.

However, most published clinical treatment studies have enrolled only relatively small patient samples, making it difficult to identify predictors of treatment response for specific approaches. Furthermore, inter-study comparability is limited because of varying methods of tinnitus assessment and different outcome parameters. Performing clinical trials according to standardized methodology and pooling the data in a database should facilitate both clinical subtypisation of different forms of tinnitus, and identification of promising treatments for different types of tinnitus. This would be an important step towards the goal of individualized treatment of tinnitus.

For these reasons, an international database of tinnitus patients, who undergo specific treatments, and are assessed during the course of this treatment with standardized instruments (e.g., psychoacoustic measures, questionnaires) has been established. The primary objectives of this database are (1) collecting a standardized set of data on patient characteristics, treatments, and outcomes from tinnitus patients consulting specialized tinnitus clinics all over the world (at present 13 centers in 8 countries), (2) delineating different subtypes of tinnitus based on data that has been systematically collected and (3) identifying predictors for individual treatment response based on the clinical profile. Starting in 2008, the database currently contains data from more than 400 patients. It is expected that more centers will join the project and that the patient numbers will rapidly grow, so that this international database will further facilitate future research and contribute to the development of evidence based on individualized treatment.

The latest buzz on tinnitus

Although often benign, tinnitus can cause significant psychological distress and may be a symptom of a life-threatening disease. Prompt diagnosis and knowledge of current treatment options are essential.