Onset Of Tinnitus Research Articles

Association between gastroesophageal reflux disease and tinnitus in a nationwide population-based cohort study

Gastroesophageal Reflux Disease (GERD) is characterized by the regurgitation of stomach contents. Recent research indicates that acid reflux may disrupt the homeostasis of the middle and inner ear through the Eustachian tube. Given this context, we hypothesized that an association between GERD and tinnitus may exist due to the imbalance of the middle and inner ear caused by acid reflux. To explore this connection, we conducted a retrospective cohort study involving 669,159 patients registered in the National Health Insurance Service-National Sample Cohort (2012–2019) in South Korea. Our data showed that GERD and tinnitus are highly associated. Nevertheless, the use of proton pump inhibitor medication in GERD patients did not show a significant decrease in the onset of tinnitus.

Tinnitus and COVID-19: effect of infection, vaccination, and the pandemic

IntroductionThe COVID-19 pandemic, which began worldwide around March 2020, has had an impact on hearing health, specifically tinnitus and hearing loss. Physiologically, COVID-19 infection, or medication used to treat the infection, has been reported to be a potential risk factor for tinnitus onset. In addition, tinnitus was reported to be a long COVID symptom or to occur after a COVID-19 vaccination in some cases. With most reports focused on the clinical population, this study aimed to investigate how the onset of tinnitus is associated with COVID-19 infection, long COVID, and COVID-19 vaccination in the general population based on self-report, while accounting for otologic and psychological symptoms.MethodsIn this study, a cross-sectional online survey that included general demographic questions, questions about tinnitus, hearing loss, hyperacusis, emotional status, and the Tinnitus Functional Index (TFI) was conducted.ResultsCompleted survey data of 1,511 respondents who reported having tinnitus or believed to have COVID-associated tinnitus were included in the analysis. Participants were categorized into four groups based on their judgment regarding the etiology of their tinnitus: (1) COVID infection group, (2) long COVID group, (3) COVID vaccination group, and (4) pre-existing tinnitus group. The results suggest that tinnitus severity (estimated using TFI scores) was significantly lower in the pre-existing tinnitus group than in any of the COVID-associated tinnitus groups. While varying factors were found to contribute to tinnitus severity among the COVID-associated groups, overall, depression and/or anxiety accounted for the most variance in predicting tinnitus severity.DiscussionThe findings highlight the need to evaluate the impact of varying otologic and psychological symptoms in individuals with COVID-associated tinnitus for better patient-centered care.

Methylphenidate and the risk of acute central nervous system oxygen toxicity: a rodent model and observational data in human divers.

The effects of methylphenidate, a stimulant often prescribed for the treatment of attention-deficit/hyperactivity disorder (ADHD), on the development of central nervous system oxygen toxicity (COT) have not been experimentally evaluated. The records of all pure-oxygen-rebreather divers evaluated at our institution from 1975-2022 were assessed. Cases of COT were defined as a new onset of tinnitus, tunnel vision, myoclonus, headache, nausea, loss of consciousness, or seizures resolving within 15 minutes from breathing normobaric air, and matched 4:1 with similar controls. Any medications issued to the diver in the preceding three months, including methylphenidate, were recorded. In the animal arm of this study, male mice were exposed to increasing doses of methylphenidate orally, with subsequent exposure to hyperbaric O₂ until clinically evident seizures were recorded. Seventy-five cases of COT were identified in divers, occurring at a median of 80 (range 2-240) minutes after dive initiation at a median depth of 5 m (2-13). Hypercarbia was documented in 11 (14.7%) cases. Prescription of methylphenidate in the preceding three months was not associated with increased risk (OR 0.72, 95% CI 0.16-3.32) of COT. In mice, increasing methylphenidate exposure dose was associated with significantly longer mean COT latency time being 877 s (95% CI 711-1,043) with doses of 0 mg·kg⁻¹; 1,312 s (95% CI 850-1,773) when given 0.75 mg·kg⁻¹; and 1,500 s (95% CI 988-2,012) with 5 mg·kg⁻¹ (F = 4.635, P = 0.014). Observational human data did not demonstrate an association between methylphenidate and an increased risk of COT. Methylphenidate exposure in mice prolongs COT latency and may have protective effects against COT.

Noise and the risk of tinnitus: A two‐sample Mendelian randomized study

AbstractObjectivesObservational studies imply that noise may increase the likelihood of developing tinnitus. However, no causal relationship has been established between the two using Mendelian randomization (MR) analysis, we aimed to determine the potential causal relationship between noise and various categories of tinnitus.MethodsWe extracted single nucleotide polymorphisms (SNPs) associated with noise and tinnitus from a large genome‐wide association study (GWAS) of European individuals. UK Biobank (UKB) provided summary data for both entities. Inverse variance weighting (IVW) was implemented as the primary method for evaluating effect estimates. Using Weighted median and MR–Egger regression, heterogeneity and pleiotropy were evaluated using sensitivity analyses.ResultsThe random‐effects IVW approach revealed a causal relationship between noise and the three onset tinnitus (odds ratio [OR] = 1.052, 95% confidence interval [CI] = 1.013–1.092, p = 0.008; OR = 1.248, 95% CI = 1.177–1.323, p = 0.001; OR = 1.133, 95% CI = 1.058–1.213, p = 0.001). Noise was not a risk factor for tinnitus in the past (OR = 0.999, 95% CI = 0.934–1.068, p = 0.969). Validation with various Mendelian randomization methodologies and sensitivity analyses confirmed the findings' consistency.ConclusionThis Mendelian Randomization study provides causal evidence that noise is a risk factor for the onset of tinnitus but is not a risk factor for developing tinnitus in the past.

Retrospective evaluation of the association between climate and seasonal change with idiopathic tinnitus

ABSTRACT Tinnitus, affecting 10–15% of adults, is a multifactorial disorder with a challenging etiology. It is often associated with sex, age, obesity, smoking, and alcohol consumption. Current literature suggests that tinnitus could be associated with seasonal variability, exhibiting seasonal patterns. Although tinnitus is suggested to follow a seasonal trend conclusive evidence associating its onset to seasonality is lacking. This study aims to evaluate the impact of seasonal variability on the prevalence of tinnitus. Data was collected from MDClone platform regarding patients admitted to ‘Clalit medical services' in Israel's southern district due to the first emergence of tinnitus symptoms between the years 2005–2020. The comparison was relaying on difference in gender, age, known risk factors for tinnitus, and date of onset of tinnitus. A total of 56,315 patients were included in this cohort study. Winter is the most common season for first admissions due to tinnitus symptoms including 16,094 patients (29%). Summer (Beta = –3.037, p = 0.012) and autumn (Beta = –3.764, p < 0.001) show a negative effect on minimal mean temperature which suggest lower tinnitus incidence in a higher temperature. Humidity and maximal mean temperature did not show any statistical significance. Except for age (mean 51.73 ± 17.49), no statistical significance was found in the prevalence of risk factors related to tinnitus. In conclusion Our findings shows that tinnitus is associated with seasonality and its trends. The incidence of tinnitus is declining over the past two decades following a peak in the winter, with age being the only significant risk factor.

Stressful life events and tinnitus : Reflections and speculations.

The role of life events has not been extensively studied in the context of tinnitus. There is, however, evidence about the psychological impact of tinnitus and about the influence of psychological processes as mediators of the tinnitus experience. On the basis of this evidence, the possibility that stressful life events can act as atrigger for tinnitus is discussed; although the evidence is fragmentary and indirect, the possibility cannot be discounted. It is argued that the onset of tinnitus and the associated clinical encounters can constitute an acute stressful life event, and the ongoing experience of tinnitus can be regarded as achronic stressful life event. Interactions between ongoing tinnitus and other life events are discussed. Possible mechanisms in terms of stress influencing predictive processing and signal detection judgments are considered.

Customized Music Therapy Combined With the Counseling and Follow-Up System: Stratified Results for Tinnitus Efficacy.

Chronic subjective tinnitus is a worldwide intractable problem. In our previous studies, customized music therapy combined with a follow-up system can reduce tinnitus perception and improve anxiety/depression. This study aims to explore which characteristics of tinnitus patients are more likely to benefit from our therapy. This study included 1031 patients with chronic subjective tinnitus, all of whom completed customized music therapy with the follow-up system. Population demographics, tinnitus characteristics, and tinnitus-related scales at pretherapy and posttherapy were collected. Huadong Hospital affiliated Fudan University, Department of Otorhinolaryngology-Head & Neck Surgery from 2018 to 2022. A paired t test and the one-way analysis of variance were utilized to the overall efficacy and stratified difference based on tinnitus duration/age/tinnitus frequency. There were significant statistical differences in the Tinnitus Handicap Inventory (THI), Tinnitus Loudness Visual Analog Scale (VAS), and Hospital Anxiety and Depression Scale (HADS)-A/D scores between pretherapy and 3 months posttherapy. THI and HADS (A/D) scores decreased the most in the 1-year duration tinnitus group. The most significant decrease in THI and VAS scores was observed in the 31- to 50-year-old tinnitus group. Patients with high-frequency tinnitus and extended high-frequency tinnitus had greater decreases generally than those with low-frequency tinnitus though no significance. Group with severe and prolonged tinnitus, shorter duration of tinnitus onset, and 31 to 50 years old benefit more from our therapy. Therefore, standardized personalized music and consulting and follow-up systems while promoting early treatment can reduce tinnitus and its comorbidities.

Switching tinnitus on or off: An initial investigation into the role of the pregenual and rostral to dorsal anterior cingulate cortices

Research indicates that hearing loss significantly contributes to tinnitus, but it alone does not fully explain its occurrence, as many people with hearing loss do not experience tinnitus. To identify a secondary factor for tinnitus generation, we examined a unique dataset of individuals with intermittent chronic tinnitus, who experience fluctuating periods of tinnitus. EEGs of healthy controls were compared to EEGs of participants who reported perceiving tinnitus on certain days, but no tinnitus on other days.. The EEG data revealed that tinnitus onset is associated with increased theta activity in the pregenual anterior cingulate cortex and decreased theta functional connectivity between the pregenual anterior cingulate cortex and the auditory cortex. Additionally, there is increased alpha effective connectivity from the dorsal anterior cingulate cortex to the pregenual anterior cingulate cortex. When tinnitus is not perceived, differences from healthy controls include increased alpha activity in the pregenual anterior cingulate cortex and heightened alpha connectivity between the pregenual anterior cingulate cortex and auditory cortex. This suggests that tinnitus is triggered by a switch involving increased theta activity in the pregenual anterior cingulate cortex and decreased theta connectivity between the pregenual anterior cingulate cortex and auditory cortex, leading to increased theta-gamma cross-frequency coupling, which correlates with tinnitus loudness. Increased alpha activity in the dorsal anterior cingulate cortex correlates with distress. Conversely, increased alpha activity in the pregenual anterior cingulate cortex can transiently suppress the phantom sound by enhancing theta connectivity to the auditory cortex. This mechanism parallels chronic neuropathic pain and suggests potential treatments for tinnitus by promoting alpha activity in the pregenual anterior cingulate cortex and reducing alpha activity in the dorsal anterior cingulate cortex through pharmacological or neuromodulatory approaches.

Vestibular Schwannoma and Tinnitus: A Systematic Review of Microsurgery Compared to Gamma Knife Radiosurgery.

Background: Vestibular schwannoma (VS) is a benign tumor of the eighth cranial nerve formed from neoplastic Schwann cells. Although VS can cause a variety of symptoms, tinnitus is one of the most distressing symptoms for patients and can greatly impact quality of life. The objective of this systematic review is to comprehensively examine and compare the outcomes related to tinnitus in patients undergoing treatment for VS. Specifically, it evaluates patient experiences with tinnitus following the removal of VS using the various surgical approaches of traditional surgical resection and gamma knife radiosurgery (GKS). By delving into various aspects such as the severity of tinnitus post-treatment, the duration of symptom relief, patient quality of life, new onset of tinnitus after VS treatment, and any potential complications or side effects, this review aims to provide a detailed analysis of VS treatment on tinnitus outcomes. Methods: Following PRISMA guidelines, articles were included from PubMed, Science Direct, Scopus, and EMBASE. Quality assessment and risk of bias analysis were performed using a ROBINS-I tool. Results: Although VS-associated tinnitus is variable in its intensity and persistence post-resection, there was a trend towards a decreased tinnitus burden in patients. Irrespective of the surgical approach or the treatment with GKS, there were cases of persistent or worsened tinnitus within the studied cohorts. Conclusion: The findings of this systematic review highlight the complex relationship between VS resection and tinnitus outcomes. These findings underscore the need for individualized patient counseling and tailored treatment approaches in managing VS-associated tinnitus. The findings of this systematic review may help in guiding clinicians towards making more informed and personalized healthcare decisions. Further studies must be completed to fill gaps in the current literature.

Mendelian randomization analyses support causal relationships between tinnitus of different stages and severity and structural characteristics of specific brain regions

This study aims to delineate the causal relationships between idiopathic tinnitus in different stages and severity and the morphological properties in specific brain regions. We utilized a two-sample bidirectional Mendelian randomization (MR) analysis to ascertain the causal effects of brain structural attributes on varying severities and stages of tinnitus. Our approach involved harnessing genetic variables derived from extensive genome-wide association studies as instrumental variables, centered mainly on pertinent single-nucleotide polymorphisms associated with tinnitus. Subsequently, we integrated this data with brain structural imaging inputs to facilitate the MR analysis. We also applied reverse MR analysis to pinpoint the critical brain regions implicated in the onset of tinnitus. Our analysis revealed a demonstrable causal relationship between tinnitus and brain structural alterations, including changes primarily within the auditory cortex and hub regions of the limbic system, as well as portions of the frontal-temporal-occipital circuit. We found that individuals exhibiting cortical thickness alterations in the bilateral peri-calcarine and right superior occipital gyrus might have previously experienced tinnitus. Changes in the cortical areas of the right rectus, left inferior frontal gyrus, and right pars-orbitalis appeared unrelated to tinnitus. Furthermore, moderate tinnitus patients showed more pronounced structural alterations. This study substantiates that tinnitus could instigate substantial structural alterations mainly within the auditory-limbic-frontal-visual system, while the reciprocal causality was not supported. Moreover, the data underscores that moderate, rather than severe, tinnitus precipitates the most significant structural changes. Morphological alterations in several specific brain areas either indicate a history of tinnitus or bear no relation to it.

Tinnitus: an underreported condition following microvascular decompression for hemifacial spasm

PurposeWhile hearing loss is a well-known condition following microvascular decompression (MVD) for hemifacial spasm (HFS), tinnitus is an underreported one. This study aims to identify prevalence, characteristics, severity, and predictors of tinnitus following MVD for HFS.MethodsA single-center cohort of 55 HFS patients completed a questionnaire approximately 5 years following MVD. Data encompassed tinnitus presence, side, type, onset, and severity measured by a 10-point Visual Analogue Scale (VAS). Descriptive, correlation, and logistic regression analyses were conducted.Results At surgery, participants’ median age was 58 years (IQR 52–65). The median duration of HFS symptoms before surgery was 5 years (IQR 3–8), slightly predominant on the left (60%). Postoperative tinnitus was reported by 20 patients (36%), versus nine (16%) that reported preoperative tinnitus. Postoperative tinnitus was ipsilateral on the surgical side in 13 patients (65%), bilateral in six (30%), and contralateral in one (5%). Among patients with bilateral postoperative tinnitus, 33% did not have this preoperatively. Tinnitus was continuous in 70% of cases and pulsatile in 30%. Onset of new tinnitus was in 58% immediately or within days, in 25% within three months, and in 17% between three months and one year after surgery. The mean severity of postoperative tinnitus was 5.1 points on the VAS. Preoperative tinnitus and presence of arachnoid adhesions had suggestive associations with postoperative tinnitus in initial analyses (p = 0.005 and p = 0.065). However, preoperative tinnitus was the only significant predictor of postoperative tinnitus (p = 0.011).ConclusionTinnitus is a common condition following MVD for HFS, with a moderate overall severity. Causes behind postoperative tinnitus remain obscure but could be related to those of postoperative hearing loss in this patient population. Clinicians should be aware of tinnitus following MVD and vigilantly monitor its occurrence, to facilitate prevention efforts and optimize outcome for HFS patients undergoing MVD.

Dental patients' tinnitus profile: prevalence, types, and associated factors with oral and maxillofacial diseases.

Maxillofacial diseases may pose a risk factor for the onset of tinnitus, and may influence the severity of its symptoms. The objective of this study was to investigate the prevalence of tinnitus among patients routinely visiting the Faculty of Dentistry and to assess the relationship between tinnitus and maxillofacial diseases. This was a prospective cross-sectional study conducted on 3,626 patients. Demographic data, information on tinnitus symptoms, temporomandibular disorder (TMD) presence, the existence of trigger points in masticatory muscles, toothache, and bruxism were evaluated. Tinnitus was detected in 385 patients, resulting in a prevalence rate of 10.61%. Of the patients, 38.4% were male and 61.6% were female, and the mean age was 42.66 ± 16.34 years. Tinnitus was categorised as normal in 47.8% of the patients and pathological in 52.2% of the patients. Bruxism was identified in 65.5% of the patients, toothache in 42.9%, TMD in 33.8%, and masticatory trigger points in 27.0% of the patients. A tendency towards tinnitus provoked by toothache was observed in 5.9% of the patients. The presence of pathological tinnitus was found to increase the risk by 1.839 times for toothache and 1.456 times for bruxism. There may be an association between oral and maxillofacial diseases and tinnitus, especially bruxism and toothache. Therefore, the evaluation of these conditions may be a routine part of tinnitus management.

Cerebral venous congestion alters CNS homeostatic plasticity, evoking tinnitus-like behavior

BackgroundBrain function and neuronal activity depend on a constant supply of blood from the cerebral circulation. The cerebral venous system (CVS) contains approximately 70% of the total cerebral blood volume; similar to the cerebral arterial system, the CVS plays a prominent role in the maintenance of central nervous system (CNS) homeostasis. Impaired venous autoregulation, which can appear in forms such as cerebral venous congestion, may lead to metabolic abnormalities in the brain, causing severe cerebral functional defects and even chronic tinnitus. However, the role of cerebral venous congestion in the progression of tinnitus is underrecognized, and its pathophysiology is still incompletely understood. This study elucidated the specific pathogenetic role of cerebral venous congestion in the onset and persistence of tinnitus and the possible neurophysiological mechanisms.ResultsWe found that a rat model of cerebral venous congestion exhibited tinnitus-like behavioral manifestations at 14 days postoperatively; from that point onward, they showed signs of persistent tinnitus without significant hearing impairment. Subsequent neuroimaging and neurochemical findings showed CNS homeostatic plasticity disturbance in rats with cerebral venous congestion, reflected in increased neural metabolic activity, ultrastructural synaptic changes, upregulated synaptic efficacy, reduced inhibitory synaptic transmission (due to GABA deficiency), and elevated expression of neuroplasticity-related proteins in central auditory and extra-auditory pathways.ConclusionCollectively, our data suggest that alternations in CNS homeostatic plasticity may play a vital role in tinnitus pathology caused by cerebral venous congestion. These findings provide a new perspective on tinnitus related to cerebral venous congestion and may facilitate the development of precise interventions to interrupt its pathogenesis.

Predictive factors of tinnitus after vestibular schwannoma surgery: a case-control study

BackgroundTinnitus is very common in patients with vestibular schwannoma (VS). We analyzed the related factors of tinnitus after surgery.MethodsOne hundred seventy-three patients diagnosed with unilateral VS operated via the retrosigmoid approach were included in the study. All patients underwent relevant examinations and completed the THI scale before surgery and 6 months after surgery. The prognosis of tinnitus was evaluated according to the changes in THI.ResultsOf the 129 preoperative tinnitus patients, postoperative tinnitus resolved in 12.4%, improved in 29.5%, remained unchanged in 28.6%, and worsened in 29.5%. 18.2% of 44 patients without preoperative tinnitus appeared new-onset tinnitus postoperatively. Thirty-six patients never had tinnitus. Patients with smaller tumor sizes (≤ 3 cm) were more likely to experience preoperative tinnitus. Younger patients and those with serviceable hearing preoperatively were more likely to report their tinnitus unchanged or worsened. A new onset of postoperative tinnitus in the preoperative non-tinnitus group was found in better preoperative hearing function.ConclusionsIn this study, 70% of patients had persistent tinnitus after vestibular schwannoma resection. The prognosis of tinnitus was influenced by age and preoperative hearing function. Tinnitus is a bothersome symptom and is often underestimated by doctors. Assessment of tinnitus is mandatory during the management of vestibular schwannoma.

Neuroprotection Role of Vitamin C by Upregulating Glutamate Transporter-1 in Auditory Cortex of Noise-Induced Tinnitus Animal Model.

Vitamin C (Vc) plays a pivotal role in a series of pathological processes, such as tumors, immune diseases, and neurological disorders. However, its therapeutic potential for tinnitus management remains unclear. In this study, we find that Vc relieves tinnitus in noise-exposed rats. In the 7-day therapy groups, spontaneous firing rate (SFR) increases from 1.17 ± 0.10 Hz to 1.77 ± 0.15 Hz after noise exposure. Vc effectively reduces the elevated SFR to 0.99 ± 0.07 and 0.55 ± 0.05 Hz at different doses. The glutamate level in auditory cortex of noise-exposed rats (3.78 ± 0.42 μM) increases relative to that in the control group (1.34 ± 0.22 μM). High doses of Vc (500 mg/kg/day) effectively reduce the elevated glutamate levels (1.49 ± 0.28 μM). Mechanistic studies show that the expression of glutamate transporter 1 (GLT-1) is impaired following noise exposure and that Vc treatment effectively restores GLT-1 expression in the auditory cortex. Meanwhile, the GLT-1 inhibitor, dl-threo-beta-benzyloxyaspartic acid (dl-TBOA), invalidates the protection role of Vc. Our finding shows that Vc substantially enhances glutamate clearance by upregulating GLT-1 and consequently alleviates noise-induced tinnitus. This study provides valuable insight into a novel biological target for the development of therapeutic interventions that may prevent the onset of tinnitus.

Functional Connectivity Alterations and Molecular Characterization of the Anterior Cingulate Cortex in Tinnitus Pathology without Hearing Loss.

Compared with individuals with hearing loss, tinnitus patients without hearing loss have more psychological or emotional problems. Tinnitus is closely associated to abnormal metabolism and function of the limbic system, a key brain region for emotion experience, but the underlying molecular mechanism remains unknown. Using whole-brain microvasculature dynamics imaging, the anterior cingulate cortex (ACC) is identified as a key brain region of limbic system involve in the onset of salicylate-induced tinnitus in mice. In the tinnitus group, there is enhanced purine metabolism, oxidative phosphorylation, and a distinct pattern of phosphorylation in glutamatergic synaptic pathway according to the metabolome profiles, quantitative proteomic, and phosphoproteomic data of mice ACC tissue. Electroencephalogram in tinnitus patients with normal hearing thresholds show that the functional connectivity between pregenual anterior cingulate cortex and the primary auditory cortex is significantly increased for high-gamma frequency band, which is positively correlated with the serum glutamate level. These findings indicate that ACC plays an important role in the pathophysiology of tinnitus by interacting with the primary auditory cortex and provide potential molecular targets in the ACC for tinnitus treatment.

Temporal Changes in Functional and Structural Neuronal Activities in Auditory System in Non-Severe Blast-Induced Tinnitus.

Background and Objectives: Epidemiological data indicate that blast exposure is the most common morbidity responsible for mild TBI among Service Members (SMs) during recent military operations. Blast-induced tinnitus is a comorbidity frequently reported by veterans, and despite its wide prevalence, it is also one of the least understood. Tinnitus arising from blast exposure is usually associated with direct structural damage that results in a conductive and sensorineural impairment in the auditory system. Tinnitus is also believed to be initiated by abnormal neuronal activities and temporal changes in neuroplasticity. Clinically, it is observed that tinnitus is frequently accompanied by sleep disruption as well as increased anxiety. In this study, we elucidated some of the mechanistic aspects of sensorineural injury caused by exposure to both shock waves and impulsive noise. The isolated conductive auditory damage hypothesis was minimized by employing an animal model wherein both ears were protected. Materials and Methods: After the exposure, the animals' hearing circuitry status was evaluated via acoustic startle response (ASR) to distinguish between hearing loss and tinnitus. We also compared the blast-induced tinnitus against the well-established sodium salicylate-induced tinnitus model as the positive control. The state of the sensorineural auditory system was evaluated by auditory brainstem response (ABR), and this test helped examine the neuronal circuits between the cochlea and inferior colliculus. We then further evaluated the role of the excitatory and inhibitory neurotransmitter receptors and neuronal synapses in the auditory cortex (AC) injury after blast exposure. Results: We observed sustained elevated ABR thresholds in animals exposed to blast shock waves, while only transient ABR threshold shifts were observed in the impulsive noise group solely at the acute time point. These changes were in concert with the increased expression of ribbon synapses, which is suggestive of neuroinflammation and cellular energy metabolic disorder. It was also found that the onset of tinnitus was accompanied by anxiety, depression-like symptoms, and altered sleep patterns. By comparing the effects of shock wave exposure and impulsive noise exposure, we unveiled that the shock wave exerted more significant effects on tinnitus induction and sensorineural impairments when compared to impulsive noise. Conclusions: In this study, we systematically studied the auditory system structural and functional changes after blast injury, providing more significant insights into the pathophysiology of blast-induced tinnitus.

Evaluation of chronic idiopathic tinnitus and its psychosocial triggers.

The tinnitus susceptibility patterns in relation to different psychological and life stressors are unknown in different cultures. To determine the comorbid psychosocial factors and behaviors associated with tinnitus and the predictors for the increase in its severity. Participants were 230 adults (males = 70; females = 160; mean age = 38.6 ± 3.3). They underwent audiograms, speech discrimination and masking testing, and neuropsychiatric evaluation. Measures used for assessment included tinnitus handicap inventory, depression anxiety stress scale 21 (DASS-21), perceived stress scale (PSS), and insomnia severity index (ISI). Patients had mean duration of tinnitus of 11.5 ± 2.5 mo. They had intact hearing perception at 250-8000 Hz and 95 (41.3%) had aggravation of tinnitus loudness by masking noise. Decompensated tinnitus was reported in 77% (n = 177). The majority had clinically significant insomnia (81.3%), somatic symptoms (75%) other than tinnitus and perceived moderate (46.1%) and high (44.3%) stress to tinnitus. The severe/extremely severe symptoms of depression, anxiety and stress were reported in 17.4%, 35.7% and 44.3%, respectively. Patients with decom-pensated type had significantly higher scores for ISI (P = 0.001) and DASS-21 (depression = 0.02, anxiety = 0.01, stress = 0.001) compared to those with compensated tinnitus. Psychiatric interviewing showed that 35.7% had non-specific anxiety disorder, 17.4% had major depression, and 19.6% fulfilled the criteria of somatization disorder. Multivariate analysis showed that the only independent predictors for tinnitus severity were the duration of tinnitus [odd ratios (OR) = 0.832, 95%CI: 0.640-1.158; P = 0.001] and PSS (OR = 0.835, 95%CI: 0.540-1.125; P = 0.001) scores. To the best of our knowledge, this is the first study in our culture to evaluate the causal relationship between psychological factors and tinnitus onset, severity and persistence. Tinnitus could be the earliest and dominant somatic symptom induced by life stressors and psychological vulnerabilities. Therefore, multidisciplinary consultation (psychologists, psychiatrists, and neurologists) is important to acknowledge among the audiologists and otolaryngologists who primarily consult patients.

Rapid Development of High-Grade Dural Arteriovenous Fistula During Pregnancy: A Case Report (P14-5.010)

<h3>Objective:</h3> We present a case of minimally symptomatic, radiographically occult dural arteriovenous fistula (dAVF) evolving into intracerebral hemorrhage shortly after pregnancy. <h3>Background:</h3> dAVFs are generally acquired arteriovenous shunts thought to be caused by pathological neo-arterialization within an occluded vein. While a relatively common entity, rapid dAVF development has rarely been described in the setting of pregnancy. <h3>Design/Methods:</h3> Case report. <h3>Results:</h3> A 30-year-old nulliparous woman was referred to our outpatient clinic following subacute onset of left-predominant pulsatile tinnitus and mild bifrontal headache. Brain magnetic resonance imaging (MRI) revealed diffuse evidence of intracranial hypertension, which was supported by elevated opening pressure on lumbar puncture (LP). MR angiography and venography were within normal limits. She was diagnosed with idiopathic intracranial hypertension and started on acetazolamide with improvement in symptoms. At 6-month follow-up, she was seven weeks pregnant and reported mild worsening of tinnitus After discontinuation of acetazolamide. She remained clinically stable until three weeks after an uneventful spontaneous vaginal delivery when she presented with thunderclap headache, confusion, and aphasia. Head computed tomography (CT) was significant for a 4 mL acute frontotemporal intracerebral hemorrhage. CT angiography demonstrated a large vascular malformation of the left sphenoid wing. Cerebral angiogram confirmed a dAVF fed by the left inferolateral trunk, middle meningeal arteries, and arteries of the foramina spinosum, ovale, and rotundum, and draining into enlarged cortical veins. The fistula was successfully obliterated transarterially with a liquid embolic system. Three months following embolization, she has made complete neurological recovery with resolution of tinnitus. <h3>Conclusions:</h3> Radiographically occult dAVF can emerge and become symptomatic during pregnancy and the post-partum period. Potential mechanisms include systemic changes in hormone levels, shifting hemodynamics, and local phenomena of thrombosis, hypoxia, and secondary angiogenesis. Neurologists should consider this entity when evaluating women with new headache or focal symptoms in the peripartum setting. <b>Disclosure:</b> Dr. Sheibani has nothing to disclose. Dr. Voetsch has nothing to disclose. Prof. Orru has nothing to disclose. Dr. Lerner has received publishing royalties from a publication relating to health care. Dr. Culbertson has nothing to disclose.

A Heterogeneous Sample of a Spanish Tinnitus Cohort.

Taking into account heterogeneity has been highly recommended in tinnitus studies both to disentangle all diverse factors that can contribute to their complexity and to design personalized treatments. To this aim, a heterogeneous sample of 270 tinnitus subjects is analyzed considering the gender (male/female), hearing condition (hearing-impaired/normal-hearing), and tinnitus severity (compensated/decompensated) subgroups. Two categorical variables (tinnitus laterality and tinnitus sound type) and four quantitative variables (average auditory threshold, age of tinnitus onset, tinnitus frequency, and tinnitus severity) are used. The percentages (for categorical variables) and mean values (for quantitative variables) of the whole sample are compared with these of each subgroup. Furthermore, correlational and hypothesis testing is applied to calculate the correlation coefficients and statistical significance, respectively. The results show that the male and female subgroups contrast in the sound type and frequency of their tinnitus, hearing-impaired and normal-hearing individuals differ, in addition, in their average auditory threshold, and the compensated/decompensated tinnitus subgroup provides significantly distinct values in tinnitus laterality and tinnitus sound.