Repurposing metformin to manage idiopathic or long COVID Tinnitus: self-report adopting a pathophysiological and pharmacological approach

Chronic tinnitus is a common neurological disorder that affects millions of patients globally with no available successful pharmacotherapy. It can be extremely bothersome to some patients to the extent that it occasionally qualifies as a disability that can hinder them from leading a normal life. In this short communication, the author discusses how he suffered from idiopathic tinnitus and how he managed to adopt a combined pathophysiological and pharmacological approach to the reason for the first time in the medical literature that low-dose metformin might be safely and effectively repurposed to manage at least a subset of tinnitus patients while discussing the potential role of adenosine receptor agonists as potential future tinnitus therapeutics.

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.

Self-reporting of hearing loss and tinnitus in the diagnosis of ototoxicity by meglumine antimoniate in patients treated for American tegumentary Leishmaniasis

INTRODUCTION

American Tegumentary Leishmaniasis (ATL) treatment is based on pentavalent antimonials (Sb5+), but these drugs have been associated to several adverse effects. Hearing loss and tinnitus during treatment with meglumine antimoniate (MA) have already been reported. This study aimed to describe the usefulness of self-reporting of hearing loss and tinnitus in diagnosing MA-induced ototoxicity.

METHODS

A prospective longitudinal study was conducted with 102 patients with parasitological diagnosis of ATL, treated with different MA schemes. The presence of clinical auditory toxicity was defined as the emergence or worsening of self-reporting hearing loss and/or tinnitus during monitoring. Measures of sensitivity, specificity, and the positive and negative predictive value of the patient's self-reporting of hearing loss and tinnitus in relation to the result of the audiometric test (considered the gold standard) were calculated.

RESULTS

The age of the evaluated patients ranged from 15 to 81 years, with a median of 41 years, and most were male (73.5%). Seventy-five patients (73.5%) had cutaneous leishmaniasis and 27 (26.5%) mucosal leishmaniasis. Eighty-six patients (84.3%) received intramuscular (IM) treatment and 16 (15.7%) were treated with intralesional MA. During treatment, 18 (17,6%) had tinnitus and 7 (6,9%) had complaint of hearing loss. 53 (52%) patients had cochlear toxicity confirmed by tone threshold audiometry and high frequency audiometry, from which 60% received a dose of 20 mg Sb5+/kg/day (p = 0.015) and 96.2% were treated with IM MA (p = 0.001). Tinnitus has greater specificity and positive predictive value than hearing loss, with a low number of false positives, but with a high false negative value.

CONCLUSION

Although the large number of false negatives suggests that self-report of hearing loss or tinnitus cannot be considered a good screening test for referring the patient to an audiometry, the low number of false positives suggests the need to value the patient's complaint for referral. Otherwise, this study reinforces the importance of audiological monitoring during treatment with MA, especially in those patients with self-reporting of hearing loss or tinnitus when treated with 20 mg Sb5+/kg/day via IM.

In Silico Study in MPO and Molecular Docking of the Synthetic Drynaran Analogues Against the Chronic Tinnitus: Modulation of the M1 Muscarinic Acetylcholine Receptor

Tinnitus is a syndrome that affects the human auditory system and is characterized by a perception of sounds in the absence of acoustic stimuli, or in total silence. Research indicates that muscarinic acetylcholine receptors (mAChRs), especially the M1 type, have a fundamental role in the alterations of auditory perceptions of tinnitus. Here, a series of computer-aided tools were used, from molecular surface analysis software to services available on the web for estimating pharmacokinetics and pharmacodynamics. The results infer that the low lipophilicity ligands, that is, the 1a-d alkyl furans, present the best pharmacokinetic profile, as compounds with an optimal alignment between permeability and clearance. However, only ligands 1a and 1b have properties that are safe for the central nervous system, the site of cholinergic modulation. These ligands showed similarity with compounds deposited in the European Molecular Biology Laboratory chemical (ChEMBL) database acting on the mAChRs M1 type, the target selected for the molecular docking test. The simulations suggest that the 1 g ligand can form the ligand-receptor complex with the best affinity energy order and that, together with the 1b ligand, they are competitive agonists in relation to the antagonist Tiotropium, in addition to acting in synergism with the drug Bromazepam in the treatment of chronic tinnitus.

Increased risk of hearing loss associated with macrolide use: a systematic review and meta-analysis

The increased risk of hearing loss with macrolides remains controversial. We aimed to systematically review and meta-analyze data on the clinical risk of hearing loss, tinnitus, and ototoxicity following macrolide use. A systematic search was conducted across PubMed, MEDLINE, Cochrane, and Embase databases from database inception to May 2023. Medical Subject Heading (MeSH) terms and text keywords were utilized, without any language restrictions. In addition to the electronic databases, two authors manually and independently searched for relevant studies in the US and European clinical trial registries and Google Scholar. Studies that involved (1) patients who had hearing loss, tinnitus, or ototoxicity after macrolide use, (2) intervention of use of macrolides such as azithromycin, clarithromycin, erythromycin, fidaxomicin, roxithromycin, spiramycin, and/or telithromycin, (3) comparisons with specified placebos or other antibiotics, (4) outcomes measured as odds ratio (OR), relative risk (RR), hazard ratio (HR), and mean difference for ototoxicity symptoms using randomized control trial (RCT)s and observational studies (case-control, cross-section, and cohort studies) were included. Data extraction was performed independently by two extractors, and a crosscheck was performed to identify any errors. ORs along with their corresponding 95% confidence intervals (CIs) were estimated using random-effects models. The Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guidelines for RCTs and Meta-Analysis of Observational Studies in Epidemiology guidelines for observational studies were followed. We assessed the hearing loss risk after macrolide use versus controls (placebos and other antibiotics). Based on data from 13 studies including 1,142,021 patients (n = 267,546 for macrolide and n = 875,089 for controls), the overall pooled OR was 1.25 (95% CI 1.07-1.47). In subgroup analysis by study design, the ORs were 1.37 (95% CI 1.08-1.73) for RCTs and 1.33 (95% CI 1.24-1.43) for case-control studies, indicating that RCT and case-control study designs showed a statistically significant higher risk of hearing loss. The group with underlying diseases such as multiple infectious etiologies (OR, 1.16 [95% CI 0.96-1.41]) had a statistically significant lower risk than the group without (OR, 1.53 [95% CI 1.38-1.70] P = .013). The findings from this systematic review and meta-analysis suggest that macrolide antibiotics increase the risk of hearing loss and that healthcare professionals should carefully consider this factor while prescribing macrolides.

The effect of vitamin B12 on idiopathic tinnitus

INTRODUCTION

Tinnitus is one of the most important challenges in the field of ear, nose and throat diseases. The aim of this study was to evaluate the effect of vitamin B12 on idiopathic tinnitus.

MATERIAL AND METHODS

In this double-blind clinical trial study, 140 patients with idiopathic tinnitus were divided into two groups, the group receiving vitamin B12 and the group receiving placebo. The first group received vitamin B12 for a month and the other group received placebo. All patients filled a THI questionnaire before the participation, one month and three months after the participation. VAS evaluation questionnaires were also filled for the patients before the participation, one month and three months after the participation. The effect of vitamin B12 on tinnitus was also assessed according to hearing loss status. The two groups were also compared regarding the side effects.

RESULTS

There was no significant differences between two groups regarding age (p.value = 0.523), gender (females (p.value = 0.810) and males (p.value = 0.789), and hearing loss status (p value = 0.651). According to VAS score, there was no significant statistical differences in tinnitus severity in each group (B12 group, p.value = 0.851 and placebo group, p.value = 0.386). There was no significant statistical differences in tinnitus severity based on VAS score between two groups before the participation (p.value = 0.560), one month (p.value = 0.485) and three months (p.value = 0.254) after the participation. According to THI criterion, there was no significant statistical differences in tinnitus severity in each group (B12 group, p.value = 0.259 and placebo group, p.value = 0.521). There was no significant statistical differences in tinnitus severity based on THI score between two groups before the participation (p.value = 0.651), one month (p.value = 0.125) and three months (p.value = 0.089) after the participation. None of the patients of the two groups had any noticeable side effects. The mean of VAS and THI also had no statistically significant difference before and after the intervention in term of hearing loss status (p.value>0.05). These results were not significantly different between the two groups in term of hearing loss status (p value>0.05).

CONCLUSION

The result of this study indicated that vitamin B12 has no distinctive effect on reducing tinnitus severity.

The potassium channels: Neurobiology and pharmacology of tinnitus

Tinnitus is a widespread public health issue that imposes a significant social burden. The occurrence and maintenance of tinnitus have been shown to be associated with abnormal neuronal activity in the auditory pathway. Based on this view, neurobiological and pharmacological developments in tinnitus focus on ion channels and synaptic neurotransmitter receptors in neurons in the auditory pathway. With major breakthroughs in the pathophysiology and research methodology of tinnitus in recent years, the role of the largest family of ion channels, potassium ion channels, in modulating the excitability of neurons involved in tinnitus has been increasingly demonstrated. More and more potassium channels involved in the neural mechanism of tinnitus have been discovered, and corresponding drugs have been developed. In this article, we review animal (mouse, rat, hamster, and guinea-pig), human, and genetic studies on the different potassium channels involved in tinnitus, analyze the limitations of current clinical research on potassium channels, and propose future prospects. The aim of this review is to promote the understanding of the role of potassium ion channels in tinnitus and to advance the development of drugs targeting potassium ion channels for tinnitus.

Essential Palatal Myoclonus and Clicking Tinnitus in a Nine-Year-Old Boy-A Case Report

The work describes a case of palatal myoclonus with distressing tinnitus in a 9-year-old boy and its successful treatment with injections of botulinum toxin. This case report discusses common questions about myoclonic-induced clicking tinnitus and provides answers. Laryngoscope, 134:397-399, 2024.

Response to OKN-007 and NAC in a Patient with Unilateral Hearing Loss and Chronic Tinnitus from Vestibular Schwannoma

BACKGROUND

Tinnitus is the perception of sound in the absence of external acoustic stimulation. Being one of the most common diseases of the ear, it has a global prevalence ranging from 4.1 to 37.2%. To date, it has been difficult to treat tinnitus as its pathophysiology is poorly understood and there are limited treatment options.

OBJECTIVE

To investigate the effect of OKN-007 (also known as HPN-07), a nitrone-based investigational drug, in combination with oral N-acetylcycsteine (NAC), for the treatment of hearing loss and chronic tinnitus under an individual expanded access protocol.

PATIENT CASE

We report the case of a patient who presented with left-sided ear fullness, mild tinnitus, and mild high frequency sensorineural hearing loss with 100% word recognition. A large enhancing mass seen on MRI revealed a vestibular schwannoma. He underwent subtotal resection of the tumor resulting in a moderate-to-profound sensorineural hearing loss and catastrophic tinnitus. The patient was treated with intravenous OKN-007 at 60 mg/kg dosed three times per week and oral NAC 2500 mg twice daily.

RESULTS

Post-treatment audiometric testing revealed an average of 16.66 dB in hearing threshold improvement in three frequencies (125, 250 and 500 Hz) with residual hearing in the affected left ear. His tinnitus loudness matching improved from 90 dB to 19 dB post-treatment. His Tinnitus Handicap Inventory improved from 86/100 (Catastrophic) to 40/100 (Moderate). He also experienced improvements in sleep, concentration, hearing, and emotional well-being, and reported significantly decreased levels of tinnitusrelated distress.

CONCLUSIONS

This case report highlights the feasibility and therapeutic potential of the combination of OKN-007 and NAC in treating hearing loss and tinnitus that warrants further investigation.

A randomized, double-blind, placebo-controlled phase 2 study of intratympanic OTO-313 in patients with moderate to severe subjective tinnitus

PURPOSE

This was a randomized, double-blind, placebo-controlled Phase 2 study to evaluate the efficacy and safety of intratympanic OTO-313 in patients with subjective unilateral tinnitus.

METHODS

Patients with moderate to severe unilateral tinnitus of 2-12 months duration were enrolled. A single intratympanic injection of OTO-313 or placebo was administered to the affected ear and patients were evaluated during a 16-weeks follow-up period. Efficacy was assessed using the Tinnitus Functional Index (TFI), daily ratings of tinnitus loudness and annoyance, and Patient Global Impression of Change (PGIC).

RESULTS

Intratympanic administration of OTO-313 and placebo produced reductions in tinnitus with a similar percentage of TFI responders at Weeks 4, 8, 12, and 16. Reductions in daily ratings of tinnitus loudness and annoyance, and PGIC scores were also similar between OTO-313 and placebo groups. No significant differences in mean TFI scores between OTO-313 and placebo were observed for pre-specified strata regarding tinnitus duration (≥ 2 to ≤ 6 months and > 6 to ≤ 12 months) and TFI baseline scores (≥ 32 to ≤ 53 points and ≥ 54 to 100 points), although the results numerically favored OTO-313 in patients in the ≥ 2 to ≤ 6 months strata. These results also demonstrated an unexpectedly high placebo response particularly amongst patients with chronic tinnitus, despite training implemented to mitigate placebo response. OTO-313 was well-tolerated with a similar incidence of adverse events compared to placebo.

CONCLUSIONS

OTO-313 did not demonstrate a significant treatment benefit relative to placebo due in part to a high placebo response. OTO-313 was safe and well-tolerated.

Alterations of auditory sensory gating in mice with noise-induced tinnitus treated with nicotine and cannabis extract

Tinnitus is a phantom sound perception affecting both auditory and limbic structures. The mechanisms of tinnitus remain unclear and it is debatable whether tinnitus alters attention to sound and the ability to inhibit repetitive sounds, a phenomenon also known as auditory gating. Here we investigate if noise exposure interferes with auditory gating and whether natural extracts of cannabis or nicotine could improve auditory pre-attentional processing in noise-exposed mice. We used 22 male C57BL/6J mice divided into noise-exposed (exposed to a 9-11 kHz narrow band noise for 1 h) and sham (no sound during noise exposure) groups. Hearing thresholds were measured using auditory brainstem responses, and tinnitus-like behavior was assessed using Gap prepulse inhibition of acoustic startle. After noise exposure, mice were implanted with multi-electrodes in the dorsal hippocampus to assess auditory event-related potentials in response to paired clicks. The results showed that mice with tinnitus-like behavior displayed auditory gating of repetitive clicks, but with larger amplitudes and longer latencies of the N40 component of the aERP waveform. The combination of cannabis extract and nicotine improved the auditory gating ratio in noise-exposed mice without permanent hearing threshold shifts. Lastly, the longer latency of the N40 component appears due to an increased sensitivity to cannabis extract in noise-exposed mice compared to sham mice. The study suggests that the altered central plasticity in tinnitus is more sensitive to the combined actions on the cholinergic and the endocannabinoid systems. Overall, the findings contribute to a better understanding of pharmacological modulation of auditory sensory gating.

Personalized music therapy combined with medication as treatment for tinnitus

OBJECTIVE

This study aimed to investigate the effects of personalized music therapy in combination with medication as a treatment for tinnitus.

PATIENTS AND METHODS

We retrospectively analyzed a total of 200 patients who were admitted to the Department of Otorhinolaryngology in our hospital from June 2018 to June 2019, with tinnitus as their primary complaint. Patients were divided into four groups based on their individual treatment methods: medication group (patients received medication only, n=40), tinnitus masking (TM) group (patients received medication plus TM, n=38), tinnitus re-training (TRT) group (patients received medication plus TRT, n=35), and personalized group (patients received medication plus personalized music therapy, n=30). The pure-tone audiometry (PTA), loudness visual analogue scale (VAS), and tinnitus handicap inventory (THI) for each patient were analyzed.

RESULTS

There were statistically significant differences in the THI and VAS scores of all groups before and after treatment (p<0.05). Following nine and twelve months of treatment, the THI and VAS scores of the TRT group and the personalized group were significantly lower than those of the other two groups (p<0.05). The THI and VAS scores of the personalized group were significantly lower than those of the TRT group (p<0.05). Additionally, THI and VAS scores were statistically different at various measurement time points in each group (p<0.05). The clinical effective rate (85.37%) of the personalized group was higher than that of the other three groups (p<0.05).

CONCLUSIONS

TM, TRT, or personalized music therapy, when combined with medication, are effective in treating patients with tinnitus. Among these methods, personalized music therapy may be the superior treatment after nine months of treatment.

[Intratympanic Drug Application - Indication and Procedure]

Neurootologic disorders of the inner ear associated with symptoms such as tinnitus, vertigo, and hearing loss are common and often cause significant distress to affected patients. Treatment options are usually limited. There are now some indications for which intratympanic drug application is a possible treatment option. Intratympanic drug administration is a simple, inexpensive therapy option with few side effects that can be used on an outpatient basis. Therefore, it should not be disregarded when indicated.

Intratympanic dexamethasone in Manières disease and symptom control

BACKGROUND

Manières disease (MD) is a chronic inner ear disease characterized by recurrent vertigo and fluctuation in auditory symptoms. Vertigo spells have a sudden onset and are difficult for patients to handle. Therefore, treating a patient with MD is still a challenge for clinicians.

AIMS

This study aims to analyse the short-term effects of intratympanic dexamethasone (ITD) on the various symptoms of unilateral MD.

MATERIALS AND METHODS

The study comprised 27 patients with unilateral MD and severe vertigo who failed medication therapy. Treatment was with ITD as an alternative to destructive therapy. Treatment is evaluated after four months.

RESULTS

Significant improvements were measured with Dizziness Handicap Inventory (DHI), Tinnitus Handicap Inventory (THI), frequency of vertigo attacks longer than 20 min, Functional Level Scale (FLS), and tinnitus sensation measured by the Analog Visual Scale (AVS). Patients with severe symptoms grading with DHI and THI experienced the most improvement. Patients have achieved substantial vertigo control in 73%.

CONCLUSION

ITD application shows improvement in controlling vertigo and tinnitus in patients under exacerbation in MD.

SIGNIFICANCE

It is a promising non-destructive addition to the 'stepwise treatment concept' in MD and can be used as a first-line treatment in vertigo control.

Discriminant Analysis of the Prognostic Factors for Hearing Outcomes in Patients with Idiopathic Sudden Sensorineural Hearing Loss

BACKGROUND

This study aims to determine and assess prognostic variables that might affect the hearing result in patients with idiopathic sudden sensorineural hearing loss following intratympanic steroid injection.

METHODS

In total, 190 patients with idiopathic sudden sensorineural hearing loss received intratympanic steroid injection. Two hearing indices (recovery and nonrecovery) will be analyzed as dependent variables; patient's age, time period between the onset of hearing loss and treatment, initial level of hearing (hearing loss pre), type of audiogram curve (upsloping, downsloping, and flat), presence of vertigo, presence of tinnitus, and diabetes) will be analyzed as prognostic factor variables.

RESULTS

Recovery was seen in 72% of the patients. Different preinjection audiogram curves and hearing grades had a significant effect on recovery, absence of vestibular symptoms and no diabetic history were noted to have a good prognosis. Delay in treatment by more than 30 days from the onset of hearing loss was associated with a worse prognosis.

CONCLUSION

Idiopathic sudden sensorineural hearing loss associated with late treatment plan more than 1 month, presence of vertigo, diabetes, and profound prehearing loss were negative prognostic factors. Whereas age, gender, and presence of tinnitus did not affect prognosis. More stable response was obtained when intratympanic steroids were added within 1 month after diagnosis, and the patient presented with mild or moderate hearing loss grade, flat or downsloping pure tone audiometery curve, and absence of vertigo and nondiabetic with significantly good results.

Effects of Oral Steroids Combined with Postauricular Steroid Injection on Patients with Sudden Sensorineural Hearing Loss with Delaying Intervention: A Retrospective Analysis

Background

In the otology clinic, we often receive some sudden sensorineural hearing loss (SSNHL) patients accompanied by annoying tinnitus, who usually visited over three weeks after the onset. Nevertheless, due to the high treatment cost and relatively low cure rate, there are still great disputes about hospitalization or not for these patients. Aim: This study aimed to perform a retrospective analysis for analyzing the efficacy of treatment with oral steroids combined with postauricular steroid injection in patients with delaying effective treatment.

Material/Methods

A total of 157 eligible SSNHL patients with delaying effective treatment over three weeks were enrolled in this study. According to different treatment methods of oral steroids with or without postauricular steroid injection, these patients were divided into three groups: PO (prednisone oral) group, PSI (prednisone oral and postauricular steroid injection) group, and PII (prednisone oral and postauricular lidocaine injection) group. The changes in level of hearing, mean subjective tinnitus loudness, and side effects were analyzed in the three groups.

Results

Hearing improvement and tinnitus remission were all observed in three groups after treatment. Compared with PO and PII groups, those patients in PSI groups had more improvement in level of hearing and mean subjective tinnitus. The level of tinnitus loudness was statistically significantly correlated with the level of PTA both before treatment and after treatment.

Conclusion

Oral steroids combined with postauricular steroid injection should be employed for treatment of SSNHL patients with delaying effective treatment over three weeks.

Prediction of network pharmacology and molecular docking-based strategy to determine potential pharmacological mechanism of Liuwei Dihuang pill against tinnitus

BACKGROUND

Liuwei Dihuang Pill is widely used to treat tinnitus in China. However, the underlying mechanism of Liuwei Dihuang Pill in treating tinnitus still remains unclear.

OBJECTIVE

To explore the potential pharmacological mechanism of Liuwei Dihuang Pill in the treatment of tinnitus based on network pharmacology and molecular docking.

METHODS

The active components of the Liuwei Dihuang Pill were obtained from the traditional Chinese medicine systems pharmacology database and analysis platform (TCMSP) database. Cytoscape software was used to draw the active component-target network diagram of Liuwei Dihuang Pill, and obtain the core components. Then the corresponding targets were also obtained from the TCMSP database. Targets related to tinnitus were obtained from the GeneCards, DisGeNET, TTD and DrugBank databases. The String database was used to construct protein-protein interaction (PPI) network of common targets of drugs and diseases, then the core targets were screened out. The Annotation, Visualization and Integrated Discovery (DAVID) database was used for gene ontology (GO) enrichment and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis of common targets. Finally, the molecular docking between the core component and the core target was carried out by AutoDock.

RESULTS

The core components of Liuwei Dihuang Pill in the treatment of tinnitus including quercetin, stigmasterol, kaempferol, β-sitosterol, tetrahydroalstonine, which may act on core targets such as STAT3, transcription factor AP-1 (JUN), tumor necrosis factor (TNF), interleukin-6 and MAPK3. HIF-1 signaling pathway, Influenza A, P53 signaling pathway, and Toll-like receptor signaling pathway play a role in anti-inflammatory, improving microcirculation in the blood-labyrinth barrier, increasing cochlear blood flow, and preventing hair cell damage. The molecular docking results showed that the affinity between core components and core targets was good.

CONCLUSION

The potential mechanism of Liuwei Dihuang Pill in the treatment of tinnitus was preliminarily discussed in this study, which may provide a theoretical basis and evidence for further experimental research.

[Scraping needling technique combined with western medication for neurogenic tinnitus of kidney essence deficiency：a randomized controlled trial]

OBJECTIVE

To compare the clinical efficacy of scraping needling technique combined with western medication and simple western medication for neurogenic tinnitus of kidney essence deficiency.

METHODS

A total of 68 patients with neurogenic tinnitus of kidney essence deficiency were randomly divided into an observation group and a control group, 34 cases in each group. In the control group, oral methylcobalamin tablets were given, 0.5 mg each time, 3 times a day; oral flunarizine hydrochloride capsules were given before bed, 5 mg each time, once a day, 4 weeks in total. On the basis of the treatment as the control group, scraping needling technique was applied at Tinghui (GB 2), Yifeng (TE 17), Yangchi (TE 4) on the affected side and Shenshu (BL 23), Lieque (LU 7), 5 min each acupoint, once a day, 5 times a week for 4 weeks. Before treatment, 2, 4 weeks into treatment and 4 weeks after treatment (follow-up), the tinnitus severity score, tinnitus visual analogue scale (VAS) score and pure tone average (PTA) were observed, and the clinical efficacy was evaluated in the two groups.

RESULTS

The tinnitus severity scores, VAS scores and PTA of each time point after treatment in the two groups were lower than those before treatment (P<0.05), and those in the observation group were lower than the control group (P<0.05). The total effective rates of each time point after treatment in the observation group were 50.0% (17/34), 79.4% (27/34), 79.4% (27/34), which were higher than 26.5% (9/34), 64.7% (22/34), 61.8% (21/34) in the control group (P<0.05).

CONCLUSION

Scraping needling technique combined with western medication could improve tinnitus severity, tinnitus volume and hearing in patients with neurogenic tinnitus of kidney essence deficiency, and its curative effect is better than simple western medication.

[Typewriter tinnitus treated with gabapentin]

Typewriter tinnitus (TT) is a rare subtype of tinnitus but different in many ways, and it is treatable in most cases with carbamazepine. TT is defined by characteristic staccato sounds like a typewriter, intermittent and chronic. Compression of the eigth cranial nerve by a vascular loop of the anterior inferior cerebellar artery is believed to be the cause of TT. Additional symptoms, paroxysmal vertigo and hemifacial spasms are often accompanying TT. This case report describes a 43-year-old woman with typical symptoms and findings, who had an excellent response to treatment with gabapentin.

Preventive Effects of Ginkgo-Extract EGb 761® on Noise Trauma-Induced Cochlear Synaptopathy

Noise trauma-induced loss of ribbon synapses at the inner hair cells (IHC) of the cochlea may lead to hearing loss (HL), resulting in tinnitus. We are convinced that a successful and sustainable therapy of tinnitus has to treat both symptom and cause. One of these causes may be the mentioned loss of ribbon synapses at the IHC of the cochlea. In this study, we investigated the possible preventive and curative effects of the Ginkgo biloba extract EGb 761® on noise-induced synaptopathy, HL, and tinnitus development in Mongolian gerbils (Meriones unguiculatus). To this end, 37 male animals received EGb 761® or placebo orally 3 weeks before (16 animals) or after (21 animals) a monaural acoustic noise trauma (2 kHz, 115 dB SPL, 75 min). Animals' hearing thresholds were determined by auditory brainstem response (ABR) audiometry. A possible tinnitus percept was assessed by the gap prepulse inhibition acoustic startle reflex (GPIAS) response paradigm. Synaptopathy was quantified by cochlear immunofluorescence histology, counting the ribbon synapses of 15 IHCs at 11 different cochlear frequency locations per ear. We found a clear preventive effect of EGb 761® on ribbon synapse numbers with the surprising result of a significant increase in synaptic innervation on the trauma side relative to placebo-treated animals. Consequently, animals treated with EGb 761® before noise trauma did not develop a significant HL and were also less affected by tinnitus compared to placebo-treated animals. On the other hand, we did not see a curative effect (EGb 761® treatment after noise trauma) of the extract on ribbon synapse numbers and, consequently, a significant HL and no difference in tinnitus development compared to the placebo-treated animals. Taken together, EGb 761® prevented noise-induced HL and tinnitus by protecting from noise trauma-induced cochlear ribbon synapse loss; however, in our model, it did not restore lost ribbon synapses.

Botulinum Toxin Can Abolish and/or Quiet Tinnitus Associated with Chronic Migraine: Serendipidous Observations

INTRODUCTION

It is well established that treatment of head and neck myofascial dysfunction can alleviate both tinnitus and chronic migraine (CM). Onabotulinumtoxin A (OnaA) has become a standard treatment for CM. In a recent systematic study a subject reported tinnitus improvement. This prompted a survey of the tinnitus in all study participants.

METHODS

Fifty-seven patients with CM at a tertiary headache referral center received intramuscular Onabotulinumtoxin A (OnaA) injections into craniocervical muscles using the "follow-the-pain" protocol for headache. Effectiveness of OnaA was assessed by changes in (i) tinnitus loudness and (ii) number of headache days.

RESULTS

Of the five patients with pre-existing tinnitus OnaA abolished the tinnitus in two, including one whose tinnitus of ten years' duration resolved permanently with one treatment. The tinnitus loudness of the other four was attenuated between 70 to 100 percent for about three months, which paralleled their headaches response. All were women who had (i) a significant improvement of their CM and (ii) headaches located fronto-temporally. None of the CM non-responders reported tinnitus. Analysis of injection sites revealed that the temporalis muscle injections were likely accounting for the tinnitus attenuation.

CONCLUSION

Tinnitus associated with chronic migraine is abolished/quieted by intramuscular craniocervical Onabotulinumtoxin A injections. These results are consistent with the dorsal cochlear nucleus hypothesis for craniocervical somatic tinnitus, as well as the association between migraine and tinnitus. This serendipitous result warrants further study of botulinum toxin for tinnitus.

Ozonetherapy In The Treatment Of Nocturnal Tinnitus

This systematic review was carried out in order to highlight the implementation of ozone therapy as a treatment for nocturnal tinnitus. It is important to note that ozone treatment has resolved nocturnal tinnitus with 100% efficacy in previous studies, producing in turn a symptomatic improvement in the patient. From these results, a high degree of efficacy can be inferred in overcoming nocturnal tinnitus treated with ozone therapy in patients with a severe index of perception of tinnitus.

Tinnitus Associated with Mild Osteomyelitis of the Temporal Bone Reversed after Conservative Antibiotic Treatment: A Case Series

The symptomatology and diagnostic tools for osteomyelitis of the temporal bone have not been well documented. Diagnosis of early stage (i.e., mild form) osteomyelitis of the temporal bone may be delayed due to the limitations of traditional computed tomography’s (CT) imaging resolution. With the advancement of high-resolution CT (HRCT) images, clinicians can now observe images that could not be observed with traditional CT imaging. In this neuro-image report, we present three patients with refractory/untreatable tinnitus. In their HRCT images, mild osteomyelitis of the temporal bone was revealed by mucosa thickening with bony sequestration of air cells, mild opacification of the air cells, and soft tissue density in the middle ear cavity, mild opacification, and bony sequestration attributed to mucosa thickening of the mastoid air cells (along with the cortical bone). All of the clinical presentations and findings in the pure tone audiometry of the reported patients improved after adequate antibiotic treatment. The current report highlights the potential benefit of HRCT to diagnose this in such patients. In addition, immediate and conservative antibiotic treatment is recommended for managing these patients shortly after the detection of mild osteomyelitis of the temporal bone. This treatment could reduce the risk of progression to the severe form.

New onset tinnitus in the absence of hearing changes following COVID-19 infection

BACKGROUND

A variety of neurosensory symptoms including tinnitus have been associated with COVID-19 infection. While most cases of tinnitus are associated with hearing loss, here we report a case of severe tinnitus following COVID-19 infection with normal thresholds through 8000 Hz.

CASE REPORT

A 49-year-old male presented with new onset severe tinnitus following COVID-19 infection. Tinnitus was bilateral, constant and nonpulsatile. Audiometric evaluation revealed normal threshold through 8000 Hz, with mild hearing loss at 16,000 Hz. Conservative measures including masking strategies failed to mitigate symptoms. A trial of gabapentin 300 mg twice per day improved tinnitus with no notable side effects.

CONCLUSION

This patient may represent a subpopulation of patients who suffer from severe tinnitus following COVID-19 infection in the setting of largely normal hearing. The pathophysiology may be distinct from the more common hearing loss associated tinnitus and perhaps neuromodulators may play a larger role in mitigating tinnitus in this patient subset.

Neuroprotective Effect of Valproic Acid on Salicylate-Induced Tinnitus

High-dose salicylate induces temporary moderate hearing loss and the perception of a high-pitched tinnitus in humans and animals. Previous studies demonstrated that high doses of salicylate increase N-methyl-d-aspartate (NMDA) receptor levels, resulting in a rise in Ca²⁺ influx and induction of excitotoxicity. Glutamate excitotoxicity is associated with failure in the maintenance of calcium homeostasis, mitochondrial dysfunction, and production of reactive oxygen species (ROS). Valproic acid (VPA) is widely used for the management of bipolar disorder, epilepsy, and migraine headaches, and is known to regulate NMDA receptor activity. In this study, we examined the beneficial effects of VPA in a salicylate-induced tinnitus model in vitro and in vivo. Cells were pretreated with VPA followed by salicylate treatment. The expression levels of NMDA receptor subunit NR2B, phosphorylated cAMP response element-binding protein—an apoptosis marker, and intracellular levels of ROS were measured using several biochemical techniques. We observed increased expression of NR2B and its related genes TNFα and ARC, increased intracellular ROS levels, and induced expression of cleaved caspase-3. These salicylate-induced changes were attenuated in the neuronal cell line SH-SY5Y and rat cortical neurons after VPA pretreatment. Together, these results provide evidence of the beneficial effects of VPA in a salicylate-induced temporary hearing loss and tinnitus model.

Intratympanic Administration of OTO-313 Reduces Tinnitus in Patients With Moderate to Severe, Persistent Tinnitus: A Phase 1/2 Study

OBJECTIVE

To evaluate the safety and exploratory efficacy of intratympanic administration of OTO-313 in patients with tinnitus.

STUDY DESIGN

Single intratympanic injection of OTO-313 evaluated in a randomized, double-blind, placebo-controlled Phase 1/2 clinical study.

SETTING

Tertiary referral centers.

PATIENTS

Patients with unilateral tinnitus (moderate-severe) with tinnitus duration 1 to 6 months.

INTERVENTIONS

Intratympanic OTO-313.

MAIN OUTCOME MEASURES

Safety and change from baseline in tinnitus functional index (TFI), daily ratings of tinnitus loudness and annoyance, and patient global impression of change (PGIC).

RESULTS

OTO-313 was well-tolerated with lower incidence of adverse events than placebo. Mean TFI reduction from baseline favored OTO-313 at Week 2, 4, and 8. A clinically meaningful, 13-point improvement on the TFI was observed in 43% (6/14) of OTO-313 patients at both Weeks 4 and 8 versus 13% (2/16) of placebo patients (ad hoc responder analysis, p-value < 0.05). Reductions in daily ratings of tinnitus loudness and annoyance favored OTO-313 compared with placebo. In OTO-313 responders, a strong correlation existed between change from baseline in TFI score and changes in tinnitus loudness, tinnitus annoyance, and PGIC.

CONCLUSIONS

OTO-313 was well-tolerated and demonstrated a higher proportion of responders than placebo across consecutive visits (Weeks 4 and 8) supporting further clinical development of OTO-313 for the treatment of tinnitus.

The effect of caffeine on tinnitus: Randomized triple-blind placebo-controlled clinical trial

Objective

To test the hypothesis that caffeine can influence tinnitus, we recruited 80 patients with chronic tinnitus and randomly allocated them into two groups (caffeine and placebo) to analyze the self-perception of tinnitus symptoms after caffeine consumption, assuming that this is an adequate sample for generalization.

Methods

The participants were randomized into two groups: one group was administered a 300-mg capsule of caffeine, and the other group was given a placebo capsule (cornstarch). A diet that restricted caffeine consumption for 24 hours was implemented. The participants answered questionnaires (the Tinnitus Handicap Inventory—THI, the Visual Analog Scale—VAS, the profile of mood state—POMS) and underwent examinations (tonal and high frequency audiometry, acufenometry (frequency measure; intensity measure and the minimum level of tinnitus masking), transient otoacoustic emissions—TEOAE and distortion product otoacoustic emissions—DPOAE assessments) at two timepoints: at baseline and after capsule ingestion.

Results

There was a significant change in mood (measured by the POMS) after caffeine consumption. The THI and VAS scores were improved at the second timepoint in both groups. The audiometry assessment showed a significant difference in some frequencies between baseline and follow-up measurements in both groups, but these differences were not clinically relevant. Similar findings were observed for the amplitude and signal-to-noise ratio in the TEOAE and DPOAE measurements.

Conclusions

Caffeine (300 mg) did not significantly alter the psychoacoustic measures, electroacoustic measures or the tinnitus-related degree of discomfort.

[Hormone replacement therapy in perimenopausal women with chronic tinnitus]

Objective:To explore and analyze the effect and indication of hormone replacement therapy（HRT） in perimenopausal women with chronic tinnitus. Methods:The perimenopausal women with chronic tinnitus were divided into mild group and moderate to severe group according to Kupperman score of menopause, and then were divided into treatment group and untreated group according to whether they received MHT treatment or not. The serum 5-HT level, tinnitus handicap inventory （THI） and Pittsburgh sleep quality index （PSQI） were compared before and after treatment. Results:In moderate to severe perimenopausal tinnitus, the serum 5-HT level, THI and PSQI in the treatment group were statistically different before and after treatment（P<0.05）, and no significant difference was found in the untreated group. In mild perimenopausal tinnitus, there was no significant difference in 5-HT levels, THI and PSQI between the treated group and the untreated group before and after treatment. The 5-HT levels were correlated with THI. The lower the 5-HT level was, the more severe tinnitus was. Conclusion:HRT is helpful in the treatment of perimenopausal chronic tinnitus, especially in moderate to severe perimenopausal patients, and is recommended for clinical use.

Evidence of Cochlear Synaptopathy and the Effect of Systemic Steroid in Acute Idiopathic Tinnitus With Normal Hearing

OBJECTIVE

To evaluate the electrophysiologic evidence of cochlear synaptopathy and the effects of systemic steroids in acute idiopathic tinnitus with normal hearing.

STUDY DESIGN

Retrospective review of medical data.

SETTING

Tertiary referral center.

PATIENTS

Fifty-nine patients who experienced acute-onset idiopathic tinnitus (within 12 weeks) with normal hearing and the same number of age- and pure-tone threshold-matched control groups.

INTERVENTION

Electrophysiologic studies of the auditory pathway, oral steroids, and ginkgo biloba.

MAIN OUTCOME MEASURES

Pure-tone thresholds, wave I and wave V amplitudes of the auditory brainstem response (ABR), tinnitus handicap inventory (THI), and visual analog scale (VAS).

RESULTS

Significantly reduced ABR wave I amplitude and wave I/wave V ratio were found in the tinnitus group compared with the no tinnitus group. Age and pure-tone threshold were significantly correlated with reduced wave I amplitude and small wave I/wave V ratio. The THI and VAS scores were decreased at 3 and 12 weeks after steroid administration; however, overall changes in THI and VAS scores were not significantly different between the steroid and ginkgo biloba groups.

CONCLUSION

Potential cochlear synaptopathy was suspected in the early stage of acute idiopathic tinnitus, even in patients with normal hearing. Age and hearing threshold were potentially associated with the development of cochlear synaptopathy. Low-dose oral steroids and ginkgo biloba induced early subjective relief of tinnitus, which maintained up to 12 weeks, however, those changes did not differ between groups.

Electrophysiological assessment and pharmacological treatment of blast-induced tinnitus

Tinnitus, the phantom perception of sound, often occurs as a clinical sequela of auditory traumas. In an effort to develop an objective test and therapeutic approach for tinnitus, the present study was performed in blast-exposed rats and focused on measurements of auditory brainstem responses (ABRs), prepulse inhibition of the acoustic startle response, and presynaptic ribbon densities on cochlear inner hair cells (IHCs). Although the exact mechanism is unknown, the “central gain theory” posits that tinnitus is a perceptual indicator of abnormal increases in the gain (or neural amplification) of the central auditory system to compensate for peripheral loss of sensory input from the cochlea. Our data from vehicle-treated rats supports this rationale; namely, blast-induced cochlear synaptopathy correlated with imbalanced elevations in the ratio of centrally-derived ABR wave V amplitudes to peripherally-derived wave I amplitudes, resulting in behavioral evidence of tinnitus. Logistic regression modeling demonstrated that the ABR wave V/I amplitude ratio served as a reliable metric for objectively identifying tinnitus. Furthermore, histopathological examinations in blast-exposed rats revealed tinnitus-related changes in the expression patterns of key plasticity factors in the central auditory pathway, including chronic loss of Arc/Arg3.1 mobilization. Using a formulation of N-acetylcysteine (NAC) and disodium 2,4-disulfophenyl-N-tert-butylnitrone (HPN-07) as a therapeutic for addressing blast-induced neurodegeneration, we measured a significant treatment effect on preservation or restoration of IHC ribbon synapses, normalization of ABR wave V/I amplitude ratios, and reduced behavioral evidence of tinnitus in blast-exposed rats, all of which accorded with mitigated histopathological evidence of tinnitus-related neuropathy and maladaptive neuroplasticity.

The effect of fibromyalgia treatment on tinnitus

OBJECTIVES

We investigated the frequency of tinnitus in fibromyalgia patients and the effect of drugs used for routine fibromyalgia on tinnitus.

METHODS

We included 101 diagnosed fibromyalgia patients. After detailed ear nose throat examination, audiometric tests and tinnitus handicap index (THI) were performed. After the tests, routine treatment for fibromyalgia was started by the physical therapy and rehabilitation department. Two months after the beginning of the treatment, THI were repeated again and the results were statistically evaluated.

RESULTS

All patients included in the study were women. 74.3% of the patients had tinnitus. Pregabalin and selective serotonin and norepinephrine reuptake inhibitor (SNRI) antidepressant-treated patients were evaluated; In both groups, there was a statistically significant difference between pre- and post-treatment tinnitus levels (p < .001). However, there was no statistically significant difference between pregabalin group and diloxetine group according to treatment results.

CONCLUSIONS

The incidence of tinnitus is high in fibromyalgia patients. That pregabalin and duloxetine agents routinely used in fibromyalgia require further experimental and human studies in order to be able to use in tinnitus.

Objective Verification of Acute Tinnitus and Validation of Efficacy of Systemic Steroids in Rats

BACKGROUND

This study was performed to identify acute tinnitus and evaluate the efficacy of steroids for noise-induced acute tinnitus by measuring the gap-prepulse inhibition of the acoustic startle (GPIAS) value in an animal model.

METHODS

Nineteen rats (the noise group [n = 7] and the noise + dexamethasone [DEX] group [n = 12]) were exposed to narrow-band noise centered at 16 kHz from a sound generator for 4 hours. The noise + DEX group received intraperitoneal steroid administration daily for 5 days (1.5 mg/kg/day) after completing noise exposure. Auditory brainstem response and GPIAS value were measured just prior to, and 1 day after noise exposure and on days 1 and 10 days after completing steroid administration. The changes in cochlear structure were evaluated by histological analysis.

RESULTS

The threshold shift was checked 1 and 10 days after intraperitoneal steroid injection, and no differences in threshold shift were observed between the two groups in each frequency except for 32 kHz 1 day after steroid injection. The mean GPIAS value in the noise + DEX group (36.4% ± 14.1%) was significantly higher than that in the noise group (16.4% ± 18.8%) 10 days after intraperitoneal steroid administration (P = 0.017). There were no pathological changes associated with noise trauma in the two groups as determined on hematoxylin and eosin and immunohistochemical staining.

CONCLUSION

An acute tinnitus model with minimal structural changes by noise exposure was set up, and used to verify tinnitus objectively by measuring the GPIAS value. Steroid therapy for control of tinnitus was validated in this animal model.

Food-induced stimulation of the antisecretory factor to improve symptoms in Meniere's disease: our results

PURPOSE

Specially processed cereals (SPC) that increase endogenous antisecretory factor (AF) synthesis have been proposed to improve symptoms of Meniere's disease (MD) with controversial results. The aim of this study was to evaluate the effects of SPC in patients with definite unilateral MD and compare the results to a treatment protocol with intravenous glycerol and dexamethasone.

METHODS

Thirteen patients with unilateral MD were treated with SPC and 13 patients were treated with intravenous glycerol and dexamethasone for 12 months. Audio-vestibular evaluation was performed before (T0) and at the end of the treatments (T12). The number of vertigo spells were evaluated before and after therapy and the Efficacy Index (EI) was calculated. Questionnaires for hearing loss (HHIA), tinnitus (THI) and quality of life (TFL) were administered.

RESULTS

EI decreased in the SPC group in the second semester compared to the first although not significantly (p = 0.6323). There was a significant reduction for THI score in the SPC group at T12 (p = 0.0325). No significant differences were found between the two groups at T0 (p = 0.4723), while a significant difference was found at T12 (p = 0.0041). Quality of life showed an improvement in daily activities in the SPC group compared to infusion therapy group.

CONCLUSION

Our study shows a reduced number of vertigo attacks and a positive effect on the discomfort generated by tinnitus and quality of life in patients with unilateral MD treated with SPC and when compared to patients treated with intravenous glycerol and dexamethasone. No effects on hearing thresholds were noted in both groups.

Comparison of the effects of the temperature of intratympanic dexamethasone injections on vertigo

OBJECTIVE

This study aimed to compare if vertigo improved in patients when the dexamethasone used in the intratympanic (IT) injection was applied at body temperature or at room temperature.

METHODS

The study included 54 patients who had undergone intratympanic treatment due to sudden hearing loss and tinnitus. The IT injection was administered to all patients, 2 times with 1-day intervals. Two different IT injection techniques were used for each patient: injecting dexamethasone at room temperature and injecting it at body temperature. Patients were asked to report the vertigo they felt immediately, and at 15 min after the injection using the visual analogue scale (VAS) and the four-point categorical rating scale (CRS-4).

RESULTS

The level of vertigo immediately after injection was lower when the dexamethasone was injected at body temperature rather that at room temperature for both the VAS and CRS-4 (p < 0.05). However, no statistical differences in the VAS and CRS-4 self-report values between the two methods were found 15 min after the injection (p > 0.05).

CONCLUSION

Vertigo due to IT decreases within minutes. When the IT drugs are administered at body temperature, temporal vertigo due to injection is lower than when they are administered at room temperature.

Bilateral clicking tinnitus due to myoclonus of middle ear muscles

Isolated middle ear myoclonus can be a cause of objective tinnitus. We present an acoustically documented case of irregular bilateral middle ear myoclonus with loud clicking, and roaring tinnitus associated with essential palatal tremor. A palatal botulinum toxin injection did not eliminate the tinnitus. Division of both middle ear tendons in both ears abolished the clicking tinnitus with no effect on hearing.

Effects of Tumor Necrosis Factor Blocker on Salicylate-Induced Tinnitus in Mice

OBJECTIVE

Neuroinflammation is considered a novel mechanism for acute tinnitus. Here, we investigated the effects of a tumor necrosis factor (TNF) blocker on the gene expression of inflammatory-cytokine in the cochlea in a tinnitus animal model.

METHODS

Enbrel® (30 mg/kg, intraperitoneally (i.p.)) were administrated to the mice with the salicylate induced tinnitus for 3 days. Tinnitus score and mRNA expression levels of TNFR1, TNFR2, and N-methyl-d-aspartate receptor subunit 2B (NR2B) and its downstream regulatory element antagonist modulator (DREAM) in the cochlea of mice were measured and compared to the control.

RESULTS

The tinnitus score significantly decreased in the Enbrel® treated group. The mRNA levels of both TNFR1 and TNFR2 were significantly lower in the treatment than in the control group. The mRNA levels of NR2B and DREAM followed a similar trend.

CONCLUSION

we found that treatment with 30 mg/ kg Enbrel® decreased salicylate-induced behavior associated with tinnitus and reduced the mRNA expression levels of TNFR1/R2, NR2B, and DREAM in the cochlea of mice. These findings supported the hypothesis that neuroinflammation might be a novel mechanism for salicylate-induced tinnitus.

Successful Treatment of Autophonia with Botulinum Toxin: Case Report

Objectives:

We sought to treat autophonia due to a patulous eustachian tube using botulinum toxin.

Methods:

Because we assumed that the patulous eustachian tube was caused by abnormal activity of paratubal muscles (tensor and levator veli palatini muscles and salpingopharyngeus muscle), paralysis was performed via injection of botulinum toxin type A in a 45-year-old female professional musician who had had chronic unilateral autophonia for 20 years. In addition to a patient interview, an endoscopic examination of the nasopharynx (posterior rhinoscopy), ear microscopy, and impedance audiometry were performed to verify the diagnosis and the outcome after treatment.

Results:

The autophonia disappeared 1 week after treatment. Normalized tympanic ventilation was verified by impedance audiometry after 8 weeks. The period of symptom relief was 9 months.

Conclusions:

The administration of botulinum toxin type A provides a new option in the treatment of patulous eustachian tube. The reliability of this method and the effect of repeated injections remains to be proved in future studies.

Therapeutic Value of Ginkgo biloba Extract EGb 761® in an Animal Model (Meriones unguiculatus) for Noise Trauma Induced Hearing Loss and Tinnitus

Noise induced hearing loss (NIHL) is a common disease in modern societies and may lead to maladaptations within the auditory system that finally result in subjective tinnitus. Available therapies may only alleviate the symptoms rather than restore normal hearing. In a previous study we demonstrated that the prophylactic application of Ginkgo biloba extract EGb 761^® significantly reduces NIHL and tinnitus development in our Mongolian gerbil (Meriones unguiculatus) animal model. Here, we tested whether the application of EGb 761^® has beneficial effects after the formation of permanent NIHL and tinnitus. To this end we monitored the therapeutic effects of EGb 761^® on noise trauma-induced changes in signal processing within the auditory system of our animal model by behavioral (acoustic startle response, ASR) and electrophysiological approaches (auditory brainstem responses, ABR). We found that–in contrast to vehicle–three weeks of daily oral EGb 761^® treatment (100 mg/kg body weight) led to a restoration of hearing thresholds back to pre-trauma conditions. In addition, all 9 animals that displayed behavioral signs of subjective tinnitus showed improvement, with 7 of them showing complete relief of tinnitus symptoms during the time of EGb 761^® treatment. After discontinuation of EGb 761^® treatment, tinnitus related behavior reappeared in all but one of these animals while auditory thresholds remained restored. A detailed analysis of ABR waves revealed that EGb 761^® treatment did not simply change auditory processing back to pre-trauma conditions, but led to subtle changes of ABR wave amplitude and latency at different levels of the auditory pathway, with an overall increase of response to low stimulus intensities and a decrease at high intensities. The functional relevance of these changes may be the observed improvement of hearing thresholds while at the same time suppression of responses to high stimulus intensities may point to a global inhibitory mechanism that counteracts tinnitus.

A pilot clinical trial of the effects of coenzyme Q10 on chronic tinnitus aurium

OBJECTIVE: To determine the short-term effects of coenzyme Q10 (CoQ10) on the antioxidative status and tinnitus expression in patients with chronic tinnitus aurium.

STUDY DESIGN: A 16-week prospective nonrandomized clinical trial (n = 20). Tinnitus and Short Form-36 Questionnaires (TQ/SF-36) were evaluated together with the plasma concentrations of CoQ10, malondialdehyde, and the total antioxidant status.

RESULTS: The mean plasma CoQ10 concentration rose under external CoQ10 supply and remained elevated after medication stopped without overall effects on the tinnitus score. However, in a subgroup of 7 patients with low initial plasma CoQ10 concentration and significant increase in the plasma CoQ10 level, a clear decrease in the TQ score was observed.

CONCLUSION: In patients with a low plasma CoQ10 concentration, CoQ10 supply may decrease the tinnitus expression.

SIGNIFICANCE: This is the first study to examine the effect of CoQ10 in chronic tinnitus aurium.

© 2007 American Academy of Otolaryngology-Head and Neck Surgery Foundation. All rights reserved.

Evaluation of botulinum toxin A in treatment of tinnitus

OBJECTIVES: The purpose of this study was to evaluate the potential benefit of botulinum toxin A in treatment of tinnitus with a prospective, double-blinded study design.

STUDY DESIGN: Double-blinded, prospective clinical study.

METHODS: Thirty patients with tinnitus were randomly placed into 1 of 2 treatment arms. Patients either received botulinum toxin A (20 to 50 units) or saline injection at the first treatment, and the opposite treatment 4 months later. Prospective data including tinnitus matching test, tinnitus handicap inventory (THI), tinnitus rating scale (TRS), and patient questionnaires were obtained over a 4-month period after each injection.

RESULTS: Twenty-six patients completed both injections and follow-up and were included in data analysis. After botulinum toxin A, subjective tinnitus changes included 7 patients improved, 3 worsened, and 16 unchanged. Following placebo, 2 patients were improved, 7 worsened, and 17 unchanged. Comparison of the treatment and placebo groups was statistically significant (P >0.005) when including better, worse, and same effects. A significant decrease in THI scores between pretreatment and 4 month postbotulinum toxin A injection ( P = 0.0422) was recorded. None of the other comparisons of pretreatment to 1 month, or pretreatment to 4 months were significantly different.

CONCLUSIONS: This small study found improvement in THI scores and patient subjective results after botulinum toxin A injection compared with placebo, suggesting a possible benefit of botulinum toxin A in tinnitus management. Larger studies need to be completed to further evaluate potential benefits of botulinum toxin A in treatment of this difficult problem.

[The value of lidocaine through different routes of administration in the treatment of tinnitus: a Meta-analysis]

OBJECTIVE

To evaluate the clinical value of lidocain in the treatment of tinnitus through three routes of administration (intravenous, intratympanic and acupoint injection) by analyzing literatures.

METHOD

Articles were collected through Hownet, Wanfang, VIP, Pubmed, SciVerse ScienceDirect, Springer and OVID, etc. The articles were strictly evaluated based on their quality. The Meta-analysis was performed to evaluate the outcomes by RevMan 5. 2 software.

RESULT

A total of 16 articles with 1203 patients were enrolled in the analysis. Their tinnitus history ranged from 7 hours to 20 years. Assessment methods include tinnitus loudness levels, severity scales and subjective feelings. None of articles refer to maintaining time, instead of "short-term", "short" and so on. A total of 133 cases received intravenous injection and the effective rate was 73.4% (98 cases). 50 cases and 332 cases received intratympanic and acupoint injection respectively and their effective rates were 74.0% and 87.7%, respectively. The effective rate ranged from 42.4% to 58.3% in control group. Meta-analysis results indicate that all three routes of lidocaine administrations are more effective than conventional methods (P < 0.05).

CONCLUSION

Different routes of lidocaine administration have a good but short time effects on the tinnitus control. It can effectively reduce the time of tinnitus habituation as a complementary treatment. But its value still needs further evaluation.

Monosialotetrahexosylganglioside Inhibits the Expression of p-CREB and NR2B in the Auditory Cortex in Rats with Salicylate-Induced Tinnitus

BACKGROUND

This study investigated the effects of monosialotetrahexosylganglioside (GM1) on the expression of N-methyl-D-aspartate receptor subunit 2B (NR2B) and phosphorylated (p)-cyclic AMP response element-binding protein (CREB) in the auditory cortex of rats with tinnitus.

METHODS

Tinnitus-like behavior in rats was tested with the gap prepulse inhibition of acoustic startle paradigm. We then investigated the NR2B mRNA and protein and p-CREB protein levels in the auditory cortex of tinnitus rats compared with normal rats.

RESULTS

Rats treated for 4 days with salicylate exhibited tinnitus. NR2B mRNA and protein and p-CREB protein levels were upregulated in these animals, with expression returning to normal levels 14 days after cessation of treatment; baseline levels of NR2B and p-CREB were also restored by GM1 administration.

CONCLUSIONS

These data suggest that chronic salicylate administration induces tinnitus via upregulation of p-CREB and NR2B expression, and that GM1 can potentially be used to treat tinnitus.

Antioxidant therapy in the elderly with tinnitus

INTRODUCTION

Several approaches have been tried for the treatment of tinnitus, from cognitive-behavioral therapies and sound enrichment to medication. In this context, antioxidants, widely used in numerous areas of medicine, appear to represent a promising approach for the control of this symptom, which often is poorly controlled.

OBJECTIVE

To evaluate the effects of antioxidant therapy for tinnitus in a group of elderly patients.

METHODS

Prospective, randomized, double-blinded, placebo-controlled clinical trial. The sample consisted of 58 subjects aged 60 years or older, with a complaint of tinnitus associated with sensorineural hearing loss. These individuals completed the Tinnitus Handicap Inventory (THI) questionnaire before and after six months of therapy. The treatment regimens were: Ginkgo biloba dry extract (120mg/day), α-lipoic acid (60mg/day)+vitamin C (600mg/day), papaverine hydrochloride (100mg/day)+vitamin E (400mg/day), and placebo.

RESULTS

There was no statistically significant difference between THI by degree (p=0.441) and by score (p=0.848) before and after treatment.

CONCLUSION

There was no benefit from the use of antioxidant agents for tinnitus in this sample.

Your questions about complementary medicines answered: gingko biloba

This is the fourth article in a series providing evidence-based answers to common questions about complementary medicines from consumers and healthcare professionals.

Scopolamine attenuates auditory cortex response

CONCLUSION

Scopolamine, a tropane alkaloid drug that mainly acts as an antagonist of muscarinic acetylcholine receptors, was found to reduce the local field potentials (LFP) of auditory cortex (AC) evoked by tone and gap-offsets whose effects may compensate the cortical hyperexcitability related to tinnitus.

OBJECTIVE

To study the effects of scopolamine on the AC and the inferior colliculus (IC) of awake rats in order to understand scopolamine's effect on tinnitus and gap detection.

METHOD

Silent gaps (duration varied from 2-100 ms) embedded in otherwise continuous noise were used to elicit AC and IC response. Gap evoked AC and IC field potentials were recorded from awake rats before and after treatment of scopolamine (3 mg/kg, i.m.).

RESULTS

Acute injection of scopolamine (3 mg/kg, i.m.) induced a significant reduction of the AC response, but not the IC response, to the offset of the gaps embedded in white noise. The results suggest that scopolamine may reduce AC neural synchrony.

[Clinical analysis of Ginkgo biloba injection combined with traditional therapy in treatment of explosive deafness]

OBJECTIVE

To investigate the clinical efficacy of Ginkgo biloba injection combined with traditional therapy in the treatment of explosive deafness.

METHODS

Fifty-six (98 ears) participants who were all coal miners were selected. These patients were diagnosed with explosive deafness. and admitted to the otolaryngology department of our hospital from May 2010 to October 2013. They were.equally divided into control group and treatment group according to the therapeutic method. The patients in the control group only received traditional therapy, such as hyperbaric oxygen, while the patients in the treatment group were given Ginkgo biloba injection in addition to the therapy for the control group. The improvement in hearing was recorded and compared between the two groups.

RESULTS

The rate of improvement in tinnitus symptom in the treatment group was 78.0% (32/41), significantly higher than that in the control group (55.6%, 25/45) (χ2=4.857, P<0.05); compared with the treatment group (93.5%, 43/46), the control group had a significant lower overall response rate at 76.9% (40/52) (χ2=5.160, P<0.05).

CONCLUSION

Compared with traditional therapy alone, combined ginkgo biloba extract injection and traditional therapy can significantly improve tinnitus symptom and overall response rate in the treatment of explosive deafness in coal miners, which suggests that the combination therapy is worthy of clinical application.