A systematic review and network meta-analysis of existing pharmacologic therapies in patients with idiopathic sudden sensorineural hearing loss

Protocol for a multicentre randomised controlled trial of STeroid Administration Routes For Idiopathic Sudden sensorineural Hearing loss: The STARFISH trial

Idiopathic sudden sensorineural hearing loss (ISSNHL) is the rapid onset of reduced hearing due to loss of function of the inner ear or hearing nerve of unknown aetiology. Evidence supports improved hearing recovery with early steroid treatment, via oral, intravenous, intratympanic or a combination of routes. The STARFISH trial aims to identify the most clinically and cost-effective route of administration of steroids as first-line treatment for ISSNHL. STARFISH is a pragmatic, multicentre, assessor-blinded, three-arm intervention, superiority randomised controlled trial (1:1:1) with an internal pilot (ISRCTN10535105, IRAS 1004878). 525 participants with ISSNHL will be recruited from approximately 75 UK Ear, Nose and Throat units. STARFISH will recruit adults with sensorineural hearing loss averaging 30dBHL or greater across three contiguous frequencies (confirmed via pure tone audiogram), with onset over a ≤3-day period, within four weeks of randomisation. Participants will be randomised to 1) oral prednisolone 1mg/Kg/day up to 60mg/day for 7 days; 2) intratympanic dexamethasone: three intratympanic injections 3.3mg/ml or 3.8mg/ml spaced 7±2 days apart; or 3) combined oral and intratympanic steroids. The primary outcome will be absolute improvement in pure tone audiogram average at 12-weeks following randomisation (0.5, 1.0, 2.0 and 4.0kHz). Secondary outcomes at 6 and 12 weeks will include: Speech, Spatial and Qualities of hearing scale, high frequency pure tone average thresholds (4.0, 6.0 and 8.0kHz), Arthur Boothroyd speech test, Vestibular Rehabilitation Benefit Questionnaire, Tinnitus Functional Index, adverse events and optional weekly online speech and pure tone hearing tests. A health economic assessment will be performed, and presented in terms of incremental cost effectiveness ratios, and cost per quality-adjusted life-year. Primary analyses will be by intention-to-treat. Oral prednisolone will be the reference. For the primary outcome, the difference between group means and 97.5% confidence intervals at each time-point will be estimated via a repeated measures mixed-effects linear regression model.

The Effect of Rivaroxaban in the Complementary Therapy of Sudden Sensorineural Hearing Loss

Background

Due to the importance of sudden sensorineural hearing loss (SSNHL) and the possible role of blood coagulation in its mechanism and the likely therapeutic effect of anticoagulants and also the lack of studies in this field, this study aimed to evaluate the effect of rivaroxaban (RXA) in the treatment of this disease.

Materials and Methods

The present double-blind randomized clinical trial study was performed on 34 patients with SSNHL. Patients were randomly divided into two groups. In the first group, in addition to corticosteroid therapy (CST), RXA 10 mg tablets were used daily for 10 days (RXA group), and in the second group, only CST (CST group) treatment was prescribed. Hearing recovery was then assessed and recorded according to the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) criteria.

Results

This study showed that the grade of hearing recovery in the RXA group (58.8%) was higher than the CST group (47.1%), but this difference was not significant (P value >0.05). Also, RXA treatment increased the odds of hearing recovery, and this difference was not statistically significant (odd ratio (95% confidence interval)(OR (95% CI): 2.327 (0.180-18.082); P value = 0.518). In contrast, delay to treatment, more increased PTA (pure tone average (PTA)), and having vertigo reduced the odds of hearing recovery by 0.138-, 0.019-, and 0.069-fold, respectively (P value <0.05).

Conclusion

According to the results of this study, although the percentage of hearing recovery was higher in the RXA group, in general, the results of the two treatments were not significantly different.

Salvage therapy for refractory sudden sensorineural hearing loss (RSSNHL): a systematic review and network meta-analysis

OBJECTIVE

Approximately 30-50% of sudden sensorineural hearing loss (SSNHL) patients show poor response to systemic steroid therapy. Additionally, the most appropriate treatment for patients with refractory sudden sensorineural hearing loss (RSSNHL) is unknown. This study aimed to explore the best treatment for RSSNHL.

DESIGN

Using a frequentist contrast-based model and PRISMA guidelines, this study compared five salvage regimes: intratympanic injection of steroids (ITS), hyperbaric oxygen (HBO) therapy, post auricle steroid injection (PSI), ITS combined with HBO therapy, and continued systemic steroids.

STUDY SAMPLE

We searched the PubMed, EMBASE, Web of Science, and Cochrane Library databases for randomised controlled trials and cohort studies comparing treatment regimens for RSSNHL.

RESULTS

Compared with the control group (no additional treatment), PSI and ITS demonstrated significant improvements. The mean hearing gain was greater after PSI (11.1 dB [95% CI, 4.4-17.9]) than after ITS (7.7 dB [95% CI, 4.8-10.7]). When a restricted definition of RSSNHL was used, the ITS + HBO therapy showed the largest difference in improvement for pure tone average compared with the control group (14.5 dB [95% CI, 4.2-25.0]).

CONCLUSIONS

The administration of either PSI or ITS leads to the greatest therapeutic effect in patients with RSSNHL. However, a consensus on the definition of RSSNHL is needed.

Efficacy of high dose systemic versus combined (systemic and intratympanic) corticosteroid therapy in idiopathic sudden sensorineural hearing loss: A prospective randomized trial and risk factor analysis

The pathophysiology and the proper treatment of idiopathic sudden sensorineural hearing loss (ISSNHL) are an ongoing subject of debate. Locally or systemic administered corticosteroids are the most accepted drugs of treatment in reference to ISSNHL (idiopathic sudden sensorineural hearing loss), however, no strong evidence nor guidelines regarding their effectiveness yet exists. In our prospective, randomized, controlled trial 78 participants were enrolled. Patients were randomly assigned based on the day of admission to two groups according to treatment: group SS (n = 43) received intravenous systemic methylprednisolone alone, and group CT (n = 35) received intratympanic dexamethasone + systemic methylprednisolone. The primary outcome was to compare the hearing outcomes between the treatment groups based on different, widely accepted categories (Siegel, Kanzaki, modified Siegel and PTA4 gain). In consideration of the secondary outcome, we examined the effect of the various risk factors on the hearing improvement. No differences were detected regarding hearing improvement between the two groups, based on any criteria [Siegel's criteria (p = 0.604); Kanzaki's criteria (p = 0.720); modified Siegel's criteria (p = 0.524) and PTA 4 gain (p = 0.569)]. However, several clinical factors such as vertigo (p = 0.039), or cardiovascular comorbidity (p = 0.02) and the severity of initial hearing loss (p = 0.033) were found to bear a significant impact upon the hearing outcome. To the best of our knowledge, this is the first randomized controlled trial comparing high dose systemic and combination corticosteroid therapy in ISSNHL patients. Our findings suggest coexisting cardiovascular comorbidity, vertigo and severity of the initial hearing loss may bear a significantly higher impact upon hearing improvement, than the additional intratympanic steroid administration. The presented trial was registered in the European Union Drug Regulating Authorities Clinical Trials Database (name: Combinated systemic and intratympanic steroid therapy in idiopathic sudden sensorineural hearing loss, No.: 2017-000658-20) and with the ethical approval of The National Institute of Pharmacy and Nutrition (OGYÉI) (protocol No.: 7621, on 2017.02.16.).

Effect of statins on hearing outcome in patients with idiopathic sudden sensorineural hearing loss

Objective

Statins have been reported to improve vascular endothelial function and microcirculation, reduce oxidative stress, and exert anti-inflammatory and protective effects against inner ear damage. Therefore, this study aimed to investigate the effect of statins on hearing prognosis in patients with idiopathic sudden sensorineural hearing loss (ISSNHL).

Methods

We reviewed the medical records of 149 patients diagnosed with ISSNHL. Clinical characteristics, hearing thresholds, statin medications, and hematological findings were investigated. First, patients with ISSNHL were assigned to the good and poor outcome groups, and factors influencing their prognosis were analyzed. Furthermore, patients with dyslipidemia were investigated to determine whether statins have therapeutic effects on ISSNHL.

Results

Significant differences in age (p = .011), days from the onset of ISSNHL to the initiation of treatment (p = .04), and hematological total cholesterol (TC; p = .015) between the good and poor outcome groups were observed. Furthermore, when hearing outcomes were investigated in patients with dyslipidemia, TC was significantly lower in the good outcome group (p = .03). Although no significant therapeutic effects of statins were observed in participants with dyslipidemia, patients in the statin-treated group were significantly older and experienced more diabetic complications than those in the non-statin-treated group.

Conclusion

Although our study showed that dyslipidemia is a poor prognostic factor for ISSNHL, statins had no significant therapeutic effects on hearing recovery in ISSNHL patients with dyslipidemia. The patients that received statin medications were significantly older and experienced more diabetic complications, which may have affected their hearing prognosis.

Level of Evidence

Level 4.

Sudden Sensorineural Hearing Loss Is Related to Endothelial Progenitor Cells and Lipoprotein-Associated Phospholipase A2

BACKGROUND

This study aimed to investigate the correlation between lipoprotein-associated phospholipase A2, endothelial progenitor cells, and sudden sensorineural hearing loss.

METHODS

The number of endothelial progenitor cells and lipoprotein-associated phospholipase A2 levels collected from peripheral blood samples were measured and compared between sudden sensorineural hearing loss group and control group.

RESULTS

The number of endothelial progenitor cells was reduced in sudden sensorineural hearing loss group compared to control group (38.88 ± 10.73 in sudden sensorineural hearing loss group vs. 77.14 ± 8.56 in control group, P <.01). The lipoprotein-associated phospholipase A2 level was markedly increased in sudden sensorineural hearing loss group compared to control group (244.94 ± 59.547 in sudden sensorineural hearing loss group vs. 189.00 ± 50.987 in control group, P <.05).

CONCLUSION

The number of endothelial progenitor cells was decreased and lipoprotein-associated phospholipase A2 levels were increased in sudden sensorineural hearing loss patients. Changes in the number of endothelial progenitor cells and lipoprotein-associated phospholipase A2 levels may be involved in the pathogenesis of sudden sensorineural hearing loss.

Is There an Association between Concurrent Epstein-Barr Virus Infection and Sudden Hearing Loss?-A Case-Control Study in an East Asian Population

Viral infection serves as the crucial etiology for the development of sudden sensorineural hearing loss (SSNHL). We aimed to investigate whether there is an association between concurrent Epstein-Barr virus (EBV) infection and SSNHL in an East Asian population. Patients who were older than 18 years of age and met the criteria of sudden hearing loss without an identifiable etiology were enrolled from July 2021 until June 2022, followed by the serological testing of IgA antibody responses against EBV-specific early antigen (EA) and viral capsid antigen (VCA) with an indirect hemagglutination assay (IHA) and real-time quantitative polymerase chain reaction (qPCR) of EBV DNA in serum before the treatment was initiated. After the treatment for SSNHL, post-treatment audiometry was performed to record the treatment response and degree of recovery. Among the 29 patients included during enrollment, 3 (10.3%) had a positive qPCR result for EBV. In addition, a trend of poor recovery of hearing thresholds was noted for those patients with a higher viral PCR titer. This is the first study to use real-time PCR to detect possible concurrent EBV infection in SSNHL. Our study demonstrated that approximately one-tenth of the enrolled SSNHL patients had evidence of concurrent EBV infection, as reflected by the positive qPCR test results, and a negative trend between hearing gain and the viral DNA PCR level was found within the affected cohort after steroid therapy. These findings indicate a possible role for EBV infection in East Asian patients with SSNHL. Further larger-scale research is needed to better understand the potential role and underlying mechanism of viral infection in the etiology of SSNHL.

Sonoporation of the Round Window Membrane on a Sheep Model: A Safety Study

Sonoporation using microbubble-assisted ultrasound increases the permeability of a biological barrier to therapeutic molecules. Application of this method to the round window membrane could improve the delivery of therapeutics to the inner ear. The aim of this study was to assess the safety of sonoporation of the round window membrane in a sheep model. To achieve this objective, we assessed auditory function and cochlear heating, and analysed the metabolomics profiles of perilymph collected after sonoporation, comparing them with those of the control ear in the same animal. Six normal-hearing ewes were studied, with one sonoporation ear and one control ear for each. A mastoidectomy was performed on both ears. On the sonoporation side, Vevo MicroMarker^® microbubbles (MBs; VisualSonics-Fujifilm, Amsterdam, The Netherlands) at a concentration of 2 × 10⁸ MB/mL were locally injected into the middle ear and exposed to 1.1 MHz sinusoidal ultrasonic waves at 0.3 MPa negative peak pressure with 40% duty cycle and 100 μs interpulse period for 1 min; this was repeated three times with 1 min between applications. The sonoporation protocol did not induce any hearing impairment or toxic overheating compared with the control condition. The metabolomic analysis did not reveal any significant metabolic difference between perilymph samples from the sonoporation and control ears. The results suggest that sonoporation of the round window membrane does not cause damage to the inner ear in a sheep model.

Spontaneous recovery rate of idiopathic sudden sensorineural hearing loss: A systematic review and meta-analysis

PURPOSE

Steroids comprise the mainstay of treatment for idiopathic sudden sensorineural hearing loss (ISSNHL). Since steroidal treatment was integrated to clinical practice guidelines, newly published no-treatment or placebo arms in clinical trials are scarce. To evaluate the effectiveness of steroidal treatment ± hyperbaric oxygen therapy, the data should be compared to spontaneous recovery. The aim of this paper is to find the most accurate spontaneous recovery rate, in the light of which, other treatment modalities should be judged.

MATERIALS AND METHODS

Eligible studies published until July 2021 were identified through systematic searches of 'PubMed', 'Web of Science' and 'Google Scholar'. Retrospective studies and randomised/non-randomised control trials involving only adult participants (≥18 years) with ISSNHL, and placebo/no treatment were included. Only articles that used the American Academy of Otolaryngology-Head and Neck Surgery's diagnostic criteria for ISSNHL were included.

RESULTS

942 records initially identified, 166 duplicates and 753 articles were excluded based on article subject, title, and abstract. The full texts of 13 articles were reviewed. Seven studies were included for qualitative synthesis, five papers included in quantitative synthesis. 180 ears were included in pooled statistics. The pooled spontaneous recovery was 60.28% (95% confidence interval [CI] = 38.88%-79.94%) with a heterogeneity of 86.0% (95% CI = 69.4%-93.6%).

CONCLUSIONS

Spontaneous recovery of ISSNHL should not be over-looked, as it may be close to 60%. This may have both clinical and research implications.

Efficacy of intratympanic or postauricular subperiosteal corticosteroid injection combined with systemic corticosteroid in the treatment of sudden sensorineural hearing loss: A prospective randomized study

Objectives

This study aimed to investigate the efficacy and safety of intratympanic or postauricular subperiosteal glucocorticoid injection combined with systemic glucocorticoid in the treatment of sudden sensorineural hearing loss (SSNHL).

Methods

This study is a prospective randomized controlled study. This study included unilateral SSNHL patients who were hospitalized in our department between January 2020 and June 2021. Patients were randomly divided into three groups (groups A, B, and C). Patients in group A were treated with an intratympanic corticosteroid injection combined with systemic corticosteroid treatment, and patients in group B received a postauricular corticosteroid injection combined with systemic corticosteroid treatment. Patients in group C (control group) were treated with systemic corticosteroid alone. The case number of groups A, B, and C was 311, 375, and 369, respectively.

Results

There was no significant difference in gender distribution, the proportion of left and right affected ears, and the average interval from onset to treatment among the three groups (P > 0.05). However, there were significant differences in their average age, distribution of audiogram type, and hearing loss levels among them (P < 0.01). Our study shows that there was no significant difference in average hearing threshold improvement before and after treatment in the three groups (P > 0.05). Regarding the complications, in group A, 33 patients (10.6%) had a transient vertigo attack during tympanic injection, which lasted for ~1-3 min. In group B, 20 patients (6.43%) complained of pain at the injection site, which disappeared after 1-3 days. No other complications occurred in all the other patients.

Conclusion

The addition of intratympanic or postauricular corticosteroid to systemic steroids did not result in a significant effect on hearing recovery in SSNHL. No obvious complications occur in SSNHL patients treated with intratympanic injection or postauricular injection of corticosteroid.

Clinical trial registration

[chictr.org.cn], registration number: ChiCTR2100048762.

Is repetitive systemic corticosteroid therapy effective for idiopathic sudden sensorineural hearing loss? a retrospective study

Introduction

Some idiopathic sudden sensorineural hearing loss (ISSHL) cases experience repetitive systemic corticosteroid treatment, but studies focusing on repetitive systemic corticosteroid administration have not been reported. Thus, we investigated the clinical characteristics and usefulness of repetitive systemic corticosteroid treatment in ISSHL cases.

Methods

We reviewed the medical records of 103 patients who received corticosteroids only in our hospital (single-treatment group), and 46 patients who presented at our hospital after receiving corticosteroids in a nearby clinic and were subsequently treated with corticosteroids again in our hospital (repetitive-treatment group). Clinical backgrounds, hearing thresholds, and hearing prognosis were assessed.

Results

The final hearing outcomes were not different between the two groups. Further, in the repetitive-treatment group, statistical differences were found between the good and poor prognosis groups in the number of days to start corticosteroid administration (p = 0.03), the dose of corticosteroid (p = 0.02), and the duration of corticosteroid administration (p = 0.02) at the previous facility. Multivariate analysis revealed a significant difference in the dose of corticosteroids administered by the previous clinic (p = 0.004).

Conclusion

The repetitive systemic corticosteroid administration might play a supplementary role in hearing improvement, and initial sufficient corticosteroid administration would lead to good hearing outcomes in an early phase of ISSHL.

Combination of Hyperbaric Oxygen Therapy and Oral Steroids for the Treatment of Sudden Sensorineural Hearing Loss: Early or Late?

Background and Objectives: Several treatments are available for sudden sensorineural hearing loss (SSNHL), but no studies have compared the different treatments based on the delay from the onset of the disease. Our study aims to compare the effect of hyperbaric oxygen therapy (HBOT), oral steroids (OS) and combination of both therapies (HBOT + OS) for treating SSNHL. Materials and Methods: This randomized study analyzed 171 patients with SSNHL. Patients were evaluated by pure tone audiometry test (PTA) at baseline (T0) and 20 days after treatment (T1). Three groups were available HBOT-A-, OS-B- and HBOT + OS-C-. After baseline PTA, patients were randomly assigned to each group. Statistical analysis was performed by one-way ANOVA and Chi-square. Results: Patients in the HBOT + OS and HBOT groups improved their auditory function (p < 0.05). HBOT was the best choice for treatment when started by 7 days from SSNHL onset, while HBOT + OS in case of late treatment. Profound SNHL recovered equally by HBOT and HBOT + OS (p < 0.05). Upsloping SNHL obtained better auditory results by HBOT compared to HBOT + OS (p < 0.05). Downsloping and flat SSNHL had the most improvement with HBOT + OS compared to HBOT only (p < 0.05). Conclusions: Combination of HBOT and OS is a valid treatment for SSNHL both in case of early and late treatment. Combination of HBOT and OS was the choice with the best results in case of treatment started >14 days from symptom onset.

Idiopathic sudden sensorineural hearing loss: A critique on corticosteroid therapy

Idiopathic sudden sensorineural hearing loss (ISSNHL) is a condition affecting 5-30 per 100,000 individuals with the potential to significantly reduce one's quality of life. The true incidence of this condition is not known because it often goes undiagnosed and/or recovers within a few days. ISSNHL is defined as a ≥30 dB loss of hearing over 3 consecutive audiometric octaves within 3 days with no known cause. The disorder is typically unilateral and most of the cases spontaneously recover to functional hearing within 30 days. High frequency losses, ageing, and vertigo are associated with a poorer prognosis. Multiple causes of ISSNHL have been postulated and the most common are vascular obstruction, viral infection, or labyrinthine membrane breaks. Corticosteroids are the standard treatment option but this practice is not without opposition. Post mortem analyses of temporal bones of ISSNHL cases have been inconclusive. This report analyzed ISSNHL studies administering corticosteroids that met strict inclusion criteria and identified a number of methodologic shortcomings that compromise the interpretation of results. We discuss the issues and conclude that the data do not support present treatment practices. The current status on ISSNHL calls for a multi-institutional, randomized, double-blind trial with validated outcome measures to provide science-based treatment guidance.

Predictive factors of acute sensorineural hearing loss in adult Japanese patients for clinical application by primary care doctors: a cross-sectional study

Background

Several methods are used for hearing loss screening; however, their benefits are uncertain. In this study, we aimed to determine the predictive factors of acute sensorineural hearing loss for clinical application by primary care doctors.

Methods

This retrospective, cross-sectional study included 365 patients with acute sensorineural hearing loss without prior therapy. The patients’ clinical data, demographic information, and medical histories were obtained, and they were asked about comorbidities. In addition, we assessed lifestyle factors such as stress level, alcohol consumption, marital status, and socioeconomic level. Logistic regression analysis was performed to investigate the diagnostic predictive ability of the selected factors associated with acute sensorineural hearing loss. The hearing levels of all patients were evaluated using pure tone audiometry.

Results

We identified significant predictive factors for acute sensorineural hearing loss. The absence of hyperacusis was a predictive factor for sudden sensorineural hearing loss. Younger age, female sex, and marital status were predictive factors for acute low-tone hearing loss. High body mass index, high socioeconomic level, low alcohol consumption, high stress level, hyperacusis, and vertigo/dizziness were predictive factors for Ménière’s disease. High body mass index and ear fullness were predictive factors for perilymph fistula. Low stress level was a predictive factor for acoustic tumours.

Conclusions

Our findings can be used to distinguish between the types of acute sensorineural hearing loss. Symptoms, physical status, and lifestyle factors identified during this study are useful markers for predicting acute sensorineural hearing loss occurrence.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12875-022-01830-8.

Intratympanic corticosteroids for sudden sensorineural hearing loss

BACKGROUND

Idiopathic sudden sensorineural hearing loss (ISSNHL) is common, and defined as a sudden decrease in sensorineural hearing sensitivity of unknown aetiology. Systemic corticosteroids are widely used, however their value remains unclear. Intratympanic injections of corticosteroids have become increasingly common in the treatment of ISSNHL.

OBJECTIVES

To assess the effects of intratympanic corticosteroids in people with ISSNHL.

SEARCH METHODS

The Cochrane ENT Information Specialist searched the Cochrane ENT Trials Register; CENTRAL (2021, Issue 9); PubMed; Ovid Embase; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials (search date 23 September 2021).

SELECTION CRITERIA

We included randomised controlled trials (RCTs) involving people with ISSNHL and follow-up of over a week. Intratympanic corticosteroids were given as primary or secondary treatment (after failure of systemic therapy).

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods, including GRADE to assess the certainty of the evidence. Our primary outcome was change in hearing threshold with pure tone audiometry. Secondary outcomes included the proportion of people whose hearing improved, final hearing threshold, speech audiometry, frequency-specific hearing changes and adverse effects.

MAIN RESULTS

We included 30 studies, comprising 2133 analysed participants. Some studies had more than two treatment arms and were therefore relevant to several comparisons. Studies investigated intratympanic corticosteroids as either primary (initial) therapy or secondary (rescue) therapy after failure of initial treatment. 1. Intratympanic corticosteroids versus systemic corticosteroids as primary therapy We identified 16 studies (1108 participants). Intratympanic therapy may result in little to no improvement in the change in hearing threshold (mean difference (MD) -5.93 dB better, 95% confidence interval (CI) -7.61 to -4.26; 10 studies; 701 participants; low-certainty). We found little to no difference in the proportion of participants whose hearing was improved (risk ratio (RR) 1.04, 95% CI 0.97 to 1.12; 14 studies; 972 participants; moderate-certainty). Intratympanic therapy may result in little to no difference in the final hearing threshold (MD -3.31 dB, 95% CI -6.16 to -0.47; 7 studies; 516 participants; low-certainty). Intratympanic therapy may increase the number of people who experience vertigo or dizziness (RR 2.53, 95% CI 1.41 to 4.54; 1 study; 250 participants; low-certainty) and probably increases the number of people with ear pain (RR 15.68, 95% CI 6.22 to 39.49; 2 studies; 289 participants; moderate-certainty). It also resulted in persistent tympanic membrane perforation (range 0% to 3.9%; 3 studies; 359 participants; very low-certainty), vertigo/dizziness at the time of injection (1% to 21%, 3 studies; 197 participants; very low-certainty) and ear pain at the time of injection (10.5% to 27.1%; 2 studies; 289 participants; low-certainty). 2. Intratympanic plus systemic corticosteroids (combined therapy) versus systemic corticosteroids alone as primary therapy We identified 10 studies (788 participants). Combined therapy may have a small effect on the change in hearing threshold (MD -8.55 dB better, 95% CI -12.48 to -4.61; 6 studies; 435 participants; low-certainty). The evidence is very uncertain as to whether combined therapy changes the proportion of participants whose hearing is improved (RR 1.27, 95% CI 1.15 to 1.41; 10 studies; 788 participants; very low-certainty). Combined therapy may result in slightly lower (more favourable) final hearing thresholds but the evidence is very uncertain, and it is not clear whether the change would be important to patients (MD -9.11 dB, 95% CI -16.56 to -1.67; 3 studies; 194 participants; very low-certainty). Some adverse effects only occurred in those who received combined therapy. These included persistent tympanic membrane perforation (range 0% to 5.5%; 5 studies; 474 participants; very low-certainty), vertigo or dizziness at the time of injection (range 0% to 8.1%; 4 studies; 341 participants; very low-certainty) and ear pain at the time of injection (13.5%; 1 study; 73 participants; very low-certainty).  3. Intratympanic corticosteroids versus no treatment or placebo as secondary therapy We identified seven studies (279 participants). Intratympanic therapy may have a small effect on the change in hearing threshold (MD -9.07 dB better, 95% CI -11.47 to -6.66; 7 studies; 280 participants; low-certainty). Intratympanic therapy may result in a much higher proportion of participants whose hearing is improved (RR 5.55, 95% CI 2.89 to 10.68; 6 studies; 232 participants; low-certainty). Intratympanic therapy may result in lower (more favourable) final hearing thresholds (MD -11.09 dB, 95% CI -17.46 to -4.72; 5 studies; 203 participants; low-certainty). Some adverse effects only occurred in those who received intratympanic injection. These included persistent tympanic membrane perforation (range 0% to 4.2%; 5 studies; 185 participants; very low-certainty), vertigo or dizziness at the time of injection (range 6.7% to 33%; 3 studies; 128 participants; very low-certainty) and ear pain at the time of injection (0%; 1 study; 44 participants; very low-certainty).  4. Intratympanic plus systemic corticosteroids (combined therapy) versus systemic corticosteroids alone as secondary therapy We identified one study with 76 participants. Change in hearing threshold was not reported. Combined therapy may result in a higher proportion with hearing improvement, but the evidence is very uncertain (RR 2.24, 95% CI 1.10 to 4.55; very low-certainty). Adverse effects were poorly reported with only data for persistent tympanic membrane perforation (rate 8.1%, very low-certainty).

AUTHORS' CONCLUSIONS

Most of the evidence in this review is low- or very low-certainty, therefore it is likely that further studies may change our conclusions.   For primary therapy, intratympanic corticosteroids may have little or no effect compared with systemic corticosteroids. There may be a slight benefit from combined treatment when compared with systemic treatment alone, but the evidence is uncertain. For secondary therapy, there is low-certainty evidence that intratympanic corticosteroids, when compared to no treatment or placebo, may result in a much higher proportion of participants whose hearing is improved, but may only have a small effect on the change in hearing threshold. It is very uncertain whether there is additional benefit from combined treatment over systemic steroids alone. Although adverse effects were poorly reported, the different risk profiles of intratympanic treatment (including tympanic membrane perforation, pain and dizziness/vertigo) and systemic treatment (for example, blood glucose problems) should be considered when selecting appropriate treatment.

Intratympanic corticosteroid as salvage therapy in treatment of idiopathic sudden sensorineural hearing loss: A systematic review and meta-analysis

Background

The standard treatment of idiopathic sudden sensorineural hearing loss (ISSNHL) constitutes of systemic oral corticosteroid. Although oral corticosteroid might revert the acute deafness, some patients with ISSNHL display a more treatment refractory course. For these patients, corticosteroid installed directly into the middle ear has become a more frequent treatment, due to the potential benefits of a high, local concentration compared to a systemic administration. As such, for patients being refractory to standard treatment, intratympanic injection of a high dosage of corticosteroid as salvage therapy may be beneficial.

Objectives

To evaluate the efficacy of intratympanic corticosteroid (ITC) as a salvage treatment of ISSNHL.

Methods

A systematic literature search was performed in relevant databases. Both randomized trials and observational studies were considered for inclusion. The risk of bias was evaluated using the Cochrane risk of bias tool (randomized trials) or ROBINS-I tool (observational studies). Meta-analysis was performed to investigate the improvement of PTA (dB) and number of patients displaying recovery following salvage ITC injections. Occurrence of serious side effects was investigated. Finally, the certainty of the evidence was evaluated using the GRADE approach.

Results

Eleven relevant studies were identified (4 randomized trials and 7 observational studies). Both observational and randomized trials showed that salvage ITC significantly increased the number of patients displaying recovery. No serious adverse events were identified in any of the included studies. The certainty of evidence ranged from moderate to very low, due to risk of bias, imprecision, and heterogeneity.

Conclusion

Collectively, our findings indicate that salvage ITC treatment may be a beneficial and safe treatment for patients with sudden hearing loss, who otherwise are refractory to standard treatment approaches. However, the evidence level indicates need for a cautious interpretation of especially the magnitude of effect and thus the extrapolation on how much the individual may improve from this treatment. Furthermore, it remains to be investigated whether treatment outcomes may vary across different patient groups presenting with ISSNHL. This potential variation in treatment response should be kept in mind, when counselling the patient.

Trial registration number

The protocol is registered in PROSPERO. Registration number: CRD42019130586.

Influence of Metabolic Syndrome on the Recovery from Idiopathic Sudden Sensorineural Hearing Loss

Introduction  Idiopathic sudden sensorineural hearing loss (ISSHL) is a disabling otologic urgency whose ethiopathogenesis is still controversial. Only in recent years metabolic syndrome (MetS) has been implicated as a possible aggravating factor in the prognosis of recovery from ISSHL.

Objective  To assess whether the preexistence of MetS interferes on hearing recovery levels.

Methods  Retrospective cohort study composed of adult (> 18 years old) ISSHL patients admitted for treatment between January 2015 and December 2019. To diagnose ISSHL, we used pure-tone audiometry, and identified MetS patients based on the criteria of the United States National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III). The treatment protocol comprised hospitalization for five days for the intravenous administration of dexamethasone, audiometric surveillance, imaging and blood analyses, and, based on recovery, the planning of rescue treatments (intratympanic administration of dexamethasone and/or hyperbaric oxygen). The Siegel criteria were used to evaluate the hearing outcomes.

Results  The final sample was composed of 81 patients, 48 without MetS (nMetS) and 33 with MetS. Regarding the Siegel recovery category, the nMetS group had significantly better results ( p  = 0.001), with 44% of complete recoveries against 6% in the MetS, and 58% of the MetS patients had the worst outcome, contrasting with 27% in the nMetS group. The nMetS group had an overall better evolution in terms of hearing recovery and had a significant improvement in the median hearing gain (20.6 dB versus 8.8 dB; p  = 0.008). Additionally, the multivariate analysis revealed that the presence of MetS is a significant risk factor for a worse outcome (odds ratio [OR] = 0.30; 95% confidence interval [95%CI] = 0.10–0.85).

Conclusion  Regardless of age, gender, the initial audiometry threshold, and autoimmunity, MetS is a clear risk factor for a worse outcome regarding the recovery of hearing after ISSHL.

Clinical Value of 3D-FLAIR MRI in Idiopathic Sudden Sensorineural Hearing Loss

BACKGROUND

Three-dimensional fluid-attenuated inversion recovery sequence magnetic resonance imaging (3D-FLAIR MRI) has been used in the diagnosis of inner ear diseases. However, the relevance of 3D-FLAIR MRI appearances with multiple features and prognosis of patients with idiopathic sudden sensorineural hearing loss (ISSNHL) remains unclear.

METHODS

This study was a retrospective trial. We recruited 1300 patients with unilateral ISSNHL hospitalized from May 2017 to January 2019. They were divided into four groups according to their 3D-FLAIR MRI appearances: normal (n = 739), inner ear hemorrhage (n = 218), increased protein content (n = 288), and blood-labyrinth barrier damage (n = 55). The correlation between 3D-FLAIR MRI appearances and the degree or type of deafness of the participants was analyzed.

RESULTS

There was a statistical difference in the deafness side (p < 0.001) and vestibular dysfunction (p < 0.001) among the four groups. There was a statistical difference in the duration of treatment (p < 0.001) and the incidence of dizziness or vertigo (p < 0.001) for patients among these groups. The degree of deafness in the patients in the inner ear hemorrhage group was significantly more severe than that of the patients in the other three groups (p < 0.001).

CONCLUSION

3D-FLAIR MRI appearances were correlated with the prognosis of patients with ISSNHL.

[Corticosteroids for acute sensorineural hearing loss treatment. The contemporary state of problem. Literature review. Part 1]

The article presents modern literary data relating to the expediency of the purpose of glucocorticosteroids in sudden sensorineural hearing loss (SSHL) of various genes. In detail, the radar molecular mechanisms and the anatomo-physiological features of the exposure to the inner ear, side effects, the introduction methods, their comparative efficacy and modern schemes of the SSHL.

Clinical features and hearing prognosis of idiopathic sudden sensorineural hearing loss in patients undergoing hemodialysis: A retrospective study

BACKGROUND

Patients undergoing hemodialysis (HD) tend to experience hearing loss, including idiopathic sudden sensorineural hearing loss (ISSHL). However, little is known about the relationship between HD and ISSHL.

OBJECTIVE

To investigate the effects of HD on the hearing level and the treatment prognosis of ISSHL.

METHODS

We reviewed the medical records of 23 patients with ISSHL receiving HD treatment (HD group) and 101 patients with ISSHL not receiving HD treatment (non-HD group), and assessed clinical features, results of audiometric tests and blood examination results.

RESULTS

Statistically significant differences were not observed in pretreatment hearing level and hearing recovery of the ear affected with ISSHL between the two groups (P > .05). Conversely, hearing thresholds in the unaffected ear were statistically different (P < .0001), and the hearing thresholds of the HD groups were significantly increased compared with those of the non-HD groups, especially at high frequency. In addition, patients with renal dysfunction not receiving HD treatment showed similar hearing thresholds in the unaffected ear when compared with patients receiving HD treatment.

CONCLUSION

HD itself did not influence the treatment prognosis of ISSHL. Renal dysfunction itself, and not HD treatment, worsened the hearing level. As similar treatment results are expected, standard treatment should be administered to patients undergoing HD.

LEVEL OF EVIDENCE

3b.

Quality Indicators for the Diagnosis and Management of Sudden Sensorineural Hearing Loss

OBJECTIVE

Sudden sensorineural hearing loss (SSNHL) is an ideal entity for quality indicator (QI) development, providing treatment challenges resulting in variable or substandard care. The American Academy of Otolaryngology-Head and Neck Surgery recently updated their SSNHL guidelines. With SSNHL demonstrating a large burden of illness, this study sought to leverage the updated guidelines and develop QIs that support quality improvement initiatives at an individual, institutional, and systems level.

METHODS

Candidate indicators (CIs) were extracted from high-quality SSNHL guidelines that were evaluated using the Appraisal of Guidelines for Research and Evaluation II tool. Each CI and its supporting evidence were summarized and reviewed by a nine-member expert panel based on validity, reliability, and feasibility of measurement. Final QIs were selected from CIs using the modified RAND Corporation-University of California, Los Angeles appropriateness methodology.

RESULTS

Fifteen CIs were identified after literature review. After the first round of evaluations, the panel agreed on 11 candidate indicators as appropriate QIs with 2 additional CIs suggested for consideration. An expert panel meeting provided a platform to discuss areas of disagreement before final evaluations. The expert panel subsequently agreed upon 11 final QIs as appropriate measures of high-quality care for SSNHL.

CONCLUSION

The 11 proposed QIs from this study are supported by evidence and expert consensus, facilitating measurement across a wide breadth of quality domains. With the recently updated SSNHL guidelines, and a greater focus on quality improvement opportunities, these QIs may be used by healthcare providers for targeted quality improvement initiatives.

Differences in hearing recovery following intratympanic alone or intravenous dexamethasone with rescue intratympanic steroids for sudden sensorineural hearing loss: A randomised trial

OBJECTIVES

This study aimed to evaluate hearing improvement at different frequencies and the safety of intratympanic (IT) and intravenous (IV) administration of dexamethasone for sudden sensorineural hearing loss (SSNHL).

METHODS

SSNHL patients were randomly divided into two groups within 72 hours after onset and received 24 days of dexamethasone therapy. Group A received IT dexamethasone once every other day for 24 days. Group B received IV dexamethasone for 12 days, followed by IT dexamethasone once every other day for the following 12 days. Hearing recovery and side effects were compared.

RESULTS

Subgroup analysis was performed to look for variation in hearing improvement in high frequency, low frequency and overall hearing at different time points. There was no evidence of a difference in hearing outcomes between IT dexamethasone and sequential IV plus IT treatments. Side effects of steroids were observed within 90 days after treatment. The local adverse effects of IT injection were mild. The systemic side effects in group B were more serious than those in group A.

CONCLUSIONS

IT dexamethasone was safer than IV dexamethasone, and there was no evidence of a difference in hearing outcomes between IT dexamethasone and sequential IV plus IT treatments. It is necessary to make individualised treatment decisions according to the patient's condition.

Imaging Parameters of the Ipsilateral Medial Geniculate Body May Predict Prognosis of Patients with Idiopathic Unilateral Sudden Sensorineural Hearing Loss on the Basis of Diffusion Spectrum Imaging

BACKGROUND AND PURPOSE

Idiopathic sudden sensorineural hearing loss is an acute unexplained onset of hearing loss. We examined the central auditory pathway abnormalities in patients with unilateral idiopathic sudden sensorineural hearing loss using diffusion spectrum imaging and the relationships between hearing recovery and diffusion spectrum imaging parameters.

MATERIALS AND METHODS

Forty-eight patients with unilateral idiopathic sudden sensorineural hearing loss with a duration of ≤2 weeks (range, 8.9 ± 4.3 days) and 20 healthy subjects underwent diffusion spectrum imaging tractography. Hearing levels were evaluated using a pure-tone average at initial presentation and 3-month follow-up. Clinical characteristics and MR imaging findings were assessed.

RESULTS

Compared with healthy control subjects, the generalized fractional anisotropy values of patients decreased significantly in the bilateral posterior limbs of the internal capsule, with no differences between the ipsilateral and contralateral sides. The quantitative anisotropy values decreased in the Brodmann area 41, contralateral medial geniculate body, bilateral lateral lemniscus, anterior limb of internal capsule, middle temporal gyrus, and anterior corona radiata. Furthermore, at 3-month follow-up, 14 patients had <15 dB of hearing gain. Receiver operating characteristic curve analysis demonstrated that generalized fractional anisotropy in the ipsilateral medial geniculate body was related to prognosis (sensitivity = 64.7%; specificity = 85.7%; area under the curve = 0.796, 95% CI, 0.661-0.931; P < .01).

CONCLUSIONS

Diffusion spectrum imaging can detect abnormalities of white matter microstructure along the central auditory pathway in patients with unilateral idiopathic sudden sensorineural hearing loss. The generalized fractional anisotropy value of the ipsilateral medial geniculate body may help to predict recovery outcomes.

Long-term administration of vitamin B12 and adenosine triphosphate for idiopathic sudden sensorineural hearing loss: a retrospective study

Background

In idiopathic sudden sensorineural hearing loss (ISSNHL), the relationship between the administration duration of vitamin B12 (vit B12) with adenosine triphosphate (ATP) and their therapeutic effect is not fully understood.

Objective

To investigate the therapeutic effect of long-term 16 (≥weeks) administration of vit B12 with ATP on the prognosis of ISSNHL patients and compare it with those of short-term (<8 weeks) and middle-term (≥8 weeks, <16 weeks) administration.

Methods

We retrospectively reviewed the medical records of 117 patients with ISSNHL treated between 2015 and 2018.

Results

The overall recovery rate was 32.5%. Initial higher hearing threshold and initial higher grade of hearing loss (HL) were associated with a poor prognosis. However, the administration duration of vit B12 and ATP did not influence the overall hearing improvement. With regard to the time course of hearing recovery, there was no significant difference in hearing recovery among the long-, middle-, and short-term administration groups until 16 weeks after treatment. However, at 16–24 weeks after initial treatment, the short-term administration group exhibited significantly lower hearing recovery than did the long-term administration groups.

Conclusions

The administration duration of vit B12 and ATP did not influence the overall hearing prognosis in ISSNHL, but long-term administration of vit B12 and ATP helped prevent the progression of HL after ISSNHL. Our results suggest that long-term administration of vit B12 and ATP is not necessarily required to treat ISSNHL patients, except for slowly progressing HL in the affected ears.

Idiopathic Sudden Sensorineural Hearing Loss in Children: A Systematic Review and Meta-analysis

Objective

Idiopathic sudden sensorineural hearing loss (ISSNHL) is uncommon in children, and its treatment and outcome are debated. We aimed to critically review evidence in the literature about treatment options and functional outcomes of pediatric ISSNHL. Additionally, we performed a meta-analysis of the results of combined systemic-intratympanic steroid therapy versus solely systemic treatment.

Data Sources

A search was run in the PubMed, Scopus, and Google Scholar databases.

Review Methods

Included articles were original ISSNHL case series, written in English, with a population age ranging from 2 to 19 years. Other study types (single case reports, editorials, and reviews) and case series with known etiology of sudden hearing loss were excluded. Descriptive data of patients, treatments, outcomes, and possible prognostic factors were extracted and recorded for every included study.

Results

Twelve articles (7 cohort and 5 case-control studies) met all the selection criteria. Based on only the studies that provided sufficient data about clinical outcome, the pooled overall recovery rate was 67.91% (95% CI, 58.34%-77.48%). No studies showed a significant difference between systemic steroid and combined systemic-intratympanic steroid. The pooled odds ratio for combined systemic-intratympanic steroid versus systemic steroid alone was 0.90 (95% CI, 0.36-2.27) based on a random effects model, ruling out any significant difference between these treatment options.

Conclusions

The results of our meta-analysis did not support combination therapy more than systemic steroid alone. Further prospective clinical trials are necessary to establish evidence-based therapies.

Perspectives on Human Hearing Loss, Cochlear Regeneration, and the Potential for Hearing Restoration Therapies

Most adults who acquire hearing loss find it to be a disability that is poorly corrected by current prosthetics. This gap drives current research in cochlear mechanosensory hair cell regeneration and in hearing restoration. Birds and fish can spontaneously regenerate lost hair cells through a process that has become better defined in the last few years. Findings from these studies have informed new research on hair cell regeneration in the mammalian cochlea. Hair cell regeneration is one part of the greater problem of hearing restoration, as hearing loss can stem from a myriad of causes. This review discusses these issues and recent findings, and places them in the greater social context of need and community.

Sudden sensorineural hearing loss: What factors influence the response to therapy?

The standard treatment of Sudden Sensorineural Hearing Loss is based on oral steroids. In addition, intratympanic steroid is currently used in patients who fail to respond to oral treatment. The aim of the present study was to evaluate, in patients affected by SSHL, factors that influence the response to systemic and intratympanic steroid treatment. A retrospective analysis was conducted on 149 patients, all treated with systemic steroids. Moreover, patients not responsive to systemic therapy were treated with intratympanic steroids as salvage therapy. Auditory gain was assessed through the recovery rate at the discharge and after 30 days. Statistical analysis demonstrated that patients with delayed treatment and down-sloping auditory curve presented a poor recovery. Linear and stepwise regression showed that hypertriglyceridemia and hyperglycemia were negative prognostic factors. The prognosis of SSHL is affected by hyperglycemia and hypertriglyceridemia suggesting that a microvascular dysfunction within the cochlea could impair hearing recovery. Intratympanic steroid treatment was used as salvage treatment, however in patients with poor prognostic factors or at risk for side effects, it could be used in association with systemic treatment.

[The efficacy of intratympanic or combined steroids as the salvage treatment for moderate-to-severe to profound sudden sensorineural hearing loss]

Objective:The objective is to investigate and compare the efficacy of intratympanic methylprednisolone or combination therapy as the salvage treatment for idiopathic sudden sensorineural hearing loss （ISSNHL）. Method:Ninety patients with moderate-to-severe to profound SSNHL which were unresponsive to the conventional treatment were recruited. Among these 90 patients, 45 patients underwent intratympanic methylprednisolone therapy （IMT） alone and 45 patients underwent systemic dexamethasone+IMT（systemic steroids+IMT）. IMT was performed every other day, with a total of four times. The pure-tone audiogram （PTA） before and after IMT or systemic steroids+IMT was conducted. And for those with tinnitus or anxiety, tinnitus handicap inventory（THI）, visual analog scale （VAS） as well as Hamilton anxiety rating scale （HAMA） were performed before and after the treatment. Result:The success rate was 31.1% with IMT and 51.1% with systemic steroids+IMT, and the difference was not significant between the two groups. The efficacy of patients with less than 30 days of onset was better than those with more than 30 days, and the difference was not significant, either. Both groups showed significant improvement in the scores of THI, VAS, and HAMA, but no significant difference was found between the two groups. Conclusion:Intratympanic methylprednisolone is recommended as the salvage treatment for patients with moderate-to-severe to profound SSNHL which showed little efficacy after the conventional treatment. Prompt medication improves the therapeutic efficacy.

Pharmacotherapy of Tinnitus

Tinnitus is a common symptom for which there is in most cases no causal therapy. The search for an improvement of tinnitus through pharmacological interventions has a long tradition. The observation that tinnitus can be transiently suppressed by the use of lidocaine has shown that the symptom is susceptible to pharmacotherapy. So far, however, no medication has been found for either acute or chronic subjective tinnitus that reliably leads to a long-term reduction or even complete disappearance of the symptom for the majority of tinnitus sufferers. Nevertheless, in everyday clinical life, drugs are frequently used, usually off-label, to relieve tinnitus or tinnitus-associated symptoms (e.g. sleep disturbance, depression, anxiety disorder or hearing loss). This chapter shows the different approaches to acute and chronic subjective tinnitus by means of pharmacotherapeutic interventions. Furthermore, this review reports on the scientific studies carried out in this area in recent years and explains the difficulties in finding a suitable medication for most forms of tinnitus. In addition, it reports on the pharmacotherapeutic options for objective tinnitus and describes the development of tinnitus as a side effect of certain drugs. Finally, possible target structures are mentioned, which should possibly be addressed in pharmacological studies in the near future.