Steroids for treatment of sudden sensorineural hearing loss: A meta-analysis of randomized controlled trials

Prevention and treatment of noise-induced hearing loss and cochlear synapse degeneration by potassium channel blockers in vivo

Noise can induce hearing loss. In particularly, noise can induce cochlear synapse degeneration leading to hidden hearing loss, which is the most common type of hearing disorders in the clinic. Currently, there is no pharmacological treatment, particularly, no post-exposure (i.e., therapeutic) treatment available in the clinic. Here, we report that systematic administration of K + channel blockers before or after noise exposure could significantly attenuate NIHL and synapse degeneration. After systematic administration of a general K-channel blocker tetraethylammonium (TEA), the elevation of auditory brainstem response (ABR) thresholds after noise-exposure significantly reduced, and the active cochlear mechanics significantly improved. The therapeutic effect was further improved as the post-exposure administration time extending to 3 days. BK channel is a predominant K + channel in the inner hair cells. Systematic administration of a BK channel blocker GAL-021 after noise exposure also ameliorated hearing loss and improved hearing behavioral responses tested by acoustic startle response (ASR). Finally, both TEA and GAL-021 significantly attenuated noise-induced ribbon synapse degeneration. These data demonstrate that K + -channel blockers can prevent and treat NIHL and cochlear synapse degeneration. Our finding may aid in developing therapeutic strategies for post-exposure treatment of NIHL and synapse degeneration.

Significance Statement

Noise is a common deafness factor affecting more 100 million people in the United States. So far, there is no pharmacological treatment available. We show here that administration of K + channel blockers after noise exposure could attenuate noise-induced hearing loss and synapse degeneration, and improved behavioral responses. This is the first time to real the K + channel blockers that could treat noise-induced hearing loss and cochlear synaptopathy after noise exposure.

Role of Oxidative Stress in Sensorineural Hearing Loss

Hearing is essential for communication, and its loss can cause a serious disruption to one's social life. Hearing loss is also recognized as a major risk factor for dementia; therefore, addressing hearing loss is a pressing global issue. Sensorineural hearing loss, the predominant type of hearing loss, is mainly due to damage to the inner ear along with a variety of pathologies including ischemia, noise, trauma, aging, and ototoxic drugs. In addition to genetic factors, oxidative stress has been identified as a common mechanism underlying several cochlear pathologies. The cochlea, which plays a major role in auditory function, requires high-energy metabolism and is, therefore, highly susceptible to oxidative stress, particularly in the mitochondria. Based on these pathological findings, the potential of antioxidants for the treatment of hearing loss has been demonstrated in several animal studies. However, results from human studies are insufficient, and future clinical trials are required. This review discusses the relationship between sensorineural hearing loss and reactive oxidative species (ROS), with particular emphasis on age-related hearing loss, noise-induced hearing loss, and ischemia-reperfusion injury. Based on these mechanisms, the current status and future perspectives of ROS-targeted therapy for sensorineural hearing loss are described.

Comparing the use of high dose to standard dose corticosteroids for the treatment of sudden sensorineural hearing loss in adults - A systematic review

OBJECTIVE

Idiopathic sudden sensorineural hearing loss (SSNHL) is typically treated with systematic or intratympanic corticosteroids. Current ENT-UK guidelines suggest treatment with a dose of oral prednisolone 1mg/kg/day for 7 days then tapered over a further 5 days. However, there is no consensus on the effectiveness of corticosteroids for idiopathic SSNHL and no universally accepted optimal regime. The objective of this systematic review was to examine the effect of high dose versus standard dose corticosteroids in the management of idiopathic SSNHL.

METHODS

A systematic review was performed of all published data related to patients with idiopathic SSNHL who were treated acutely with high dose corticosteroid therapy. Articles were included that reported data on high dose, or comparing standard dose to high dose, oral or intravenous corticosteroid therapy for the treatment of patients with idiopathic sudden sensorineural hearing loss. Articles where patients received only combination treatment with intra-tympanic steroid were excluded. Risk of bias was assessed using the ROBINS-I tool and the ROB-2 tool.

RESULTS

Six studies were included in the analysis, representing 919 patients. Two prospective single-arm studies of patients with SSNHL treated with a high dose steroid regime found mean hearing level improved (79.5dB to 42.3dB) and 45.8% of idiopathic patients had complete recovery of hearing. Three retrospective case-series comparing high dose to standard dose regimes found a significantly greater improvement in hearing level (38.3dB vs. 48.8dB, P = 0.042), a greater mean absolute hearing gain (44.4dB vs. 15.1dB) and a significantly higher rate of functionally relevant recovery (35.7% vs. 7.4%, P = 0.035) in patients treated with high dose regimes. The single included prospective randomised trial found no statistically significant difference in mean hearing level or speech discrimination score between patients treated with high dose pulse steroids or a standard dose regime.

CONCLUSIONS

Our systematic review found the reported outcomes in the literature in this area to be mixed, with some studies suggesting a greater degree of hearing recovery with a high dose regime but others suggesting no difference. The overall quality of the available evidence was deemed to be low, with the studies at moderate risk of bias.

Early treatment for benign paroxysmal positional vertigo secondary to sudden sensorineural hearing loss

Sudden sensorineural hearing loss (SSNHL) accompanied by benign paroxysmal positional vertigo (BPPV) is relatively common in the clinic. There are unified standards for the treatment of primary BPPV with good reduction effect, while there are few studies on the treatment of BPPV secondary to SSNHL within 1 week of onset. The study was to investigate the treatment of BPPV secondary to SSNHL and compare its manual reduction with that of primary BPPV. We selected 90 patients with BPPV accompanied by SSNHL within a week of onset and 210 primary BPPV patients at Hebei Provincial Eye Hospital from June 2020 to December 2022. The former group was divided into the medicine group and manual reduction plus medicine group. The medicines used were extract of Ginkgo biloba leaves injection, betahistine hydrochloride injection and oral prednisone. We contrasted the efficacy respectively for posterior semicircular canal BPPV (psc-BPPV), horizontal semicircular canal BPPV (hsc-BPPV) and multiple semicircular canal BPPV (msc-BPPV). In addition, we compared the manual reduction effect for primary BPPV and manual reduction group, and the evaluation of efficacy are the intensity of nystagmus and the clinical symptoms. In the secondary BPPV group, there was no difference in efficacy between the medicine group and manual reduction group at the 7th-day after reduction for psc-BPPV, hsc-BPPV, and msc-BPPV (P > .05). The immediate effect of reduction was significantly different between the primary BPPV group and the group with SSNHL and BPPV for both psc-BPPV and hsc-BPPV (P < .05), and the effect of the primary BPPV group was better, but it was no difference for msc-BPPV (P > .05). For the treatment of BPPV accompanied by SSNHL within 1 week of onset, the additional reduction therapy showed no benefit, so we need to apply medication for SSNHL.

Systemic Steroids for Otolaryngology-Head and Neck Surgery Disorders: An Evidence-Based Primer for Clinicians

OBJECTIVE

To offer pragmatic, evidence-informed guidance on the use of systemic corticosteroids (SCS) for common otolaryngologic disorders.

DATA SOURCES

PubMed, Cochrane Library, and American Academy of Otolaryngology-Head and Neck Surgery Foundation clinical practice guidelines.

REVIEW METHODS

A comprehensive search of published literature through November 2021 was conducted on the efficacy of SCS, alone or in combination with other treatments, for managing disorders in otolaryngology and the subdisciplines. Clinical practice guidelines, systematic reviews, and randomized controlled trials, when available, were preferentially retrieved. Interventions and outcomes of SCS use were compiled to generate summary tables and narrative synthesis of findings.

CONCLUSIONS

Evidence on the effectiveness of SCS varies widely across otolaryngology disorders. High-level evidence supports SCS use for Bell's palsy, sinonasal polyposis, and lower airway disease. Conversely, evidence is weak or absent for upper respiratory tract infection, eustachian tube dysfunction, benign paroxysmal positional vertigo, adenotonsillar hypertrophy, or nonallergic rhinitis. Evidence is indeterminate for acute laryngitis, acute pharyngitis, acute sinusitis, angioedema, chronic rhinosinusitis without polyps, Ménière's disease, postviral olfactory loss, postoperative nerve paresis/paralysis, facial pain, and sudden sensorineural hearing loss.

IMPLICATIONS FOR PRACTICE

Clinicians should bring an evidence-informed lens to SCS prescribing to best counsel patients regarding the risks, anticipated benefits, and limited data on long-term effects. Alternate routes of corticosteroid administration-such as sprays, drops, inhalers, and intralesional injections-may be preferable for many disorders, particularly those that are self-limited or require a prolonged duration of therapy. Prudent use of SCS reduces the risk of medication-related adverse effects. Clinicians who are conversant with high-level evidence can achieve optimal outcomes and stewardship when prescribing SCS.

Practice trends in pediatric sudden sensorineural hearing loss management: An unresolved diagnosis

PURPOSE

Assess practice patterns amongst pediatric otolaryngologist for the management of children with SSNHL.

MATERIALS AND METHODS

A cross-sectional online survey of members of the American Society of Pediatric Otolaryngology (ASPO) was performed; 135 responded. Patterns in treatment modalities, ancillary tests, and timing of treatment and follow-up were evaluated. These patterns were compared between respondents with different characteristics (number of years in practice, clinic location, and number of pediatric SSNHL cases within the last year) using ordered logistic regression, Kruskal-Wallis, Wilcoxon rank-sum, and Fisher's exact tests.

RESULTS

Mean time from onset of hearing loss to presentation to a pediatric otolaryngologist was 10 days (range 1-60 days). The most cited reasons for delay in care were 'patient not seeking any healthcare evaluation' (65 %) and 'lack of access to obtain an audiogram' (54 %). The most ordered blood work was complete blood count (14 %) and herpes simplex testing (15 %). Complete blood count was ordered more frequently by physicians in practice for >10 years compared with those in practice 1-10 years, P = 0.03. Most respondents reported treating with systemic steroids (86/92, 93 %), including intratympanic steroids (32/92, 35 %). Treatment with systemic steroids was more common in academic compared with private practice, P = 0.03. Antivirals were the most common additional agent prescribed (14/89, 16 %). Most patients were seen in follow-up 1-4 weeks after diagnosis (63/85, 74 %).

CONCLUSIONS

Most pediatric otolaryngologists treat SSNHL with systemic steroids. The remainder of the diagnostic and management paradigm varies significantly, highlighting the need to systematically define which treatment optimizes outcomes in this population.

The impact of eustachian tube function on intra-tympanic steroid administration

OBJECTIVES

This study investigated the impact of eustachian tube (ET) function (ETF) on therapeutic success on candidates for intra-tympanic administration of steroids (ITAoS), due to idiopathic sudden sensorineural hearing loss (ISSNHL).

METHODS

Medical chart review in two university-affiliated medical centers was performed. Included were consecutive adult patients diagnosed with unilateral ISSNHL between 2012 and 2019 who were treated with ITAoS due to incomplete or no recovery following systemic steroidal therapy. ETF was assessed by means tympanometry, before the initiation of ITAoS. The cohort was divided into an ET dysfunction group (ETD(+)) and a functioning ET group (control: ETD(-)). The audiologic response to treatment was recorded at the last follow-up.

RESULTS

A total of 64 suitable patients [median (interquartile, IQR) age 49 (38-63) years] were enrolled. The ETD(+) group included 20 patients and the remaining 44 patients served as controls. Demographic and clinical parameters were not significantly different between the two groups at presentation. Hearing thresholds were improved significantly better, at frequencies 250, 500, 1, 2, 4, and 8 kHz (p = 0.001-0.040) in the ETD(+) group.

CONCLUSION

ETD(+) is associated with better efficacy of ITAoS.

LEVEL OF EVIDENCE: 4

Optimal timing of salvage intratympanic steroids in idiopathic sudden sensorineural hearing loss

Background

Salvage intratympanic steroids (ITS) works in patients with idiopathic sudden sensorineural hearing loss (ISSNHL) after failure of initial therapy, but optimal timing of administration is unknown.

Methods

Two hundred and seventy patients with ISSNHL were included. Among them, 180 were treated with ITS and standard medical treatment (SMT) and the other 90 received SMT along. The hearing threshold before and after salvage treatment were compared. The relationship between the salvage starting time and hearing recovery was analyzed.

Results

The hearing of ITS group improved more than that of the SMT group in all frequency bands. The effect of both strategies decreases with the delay of the starting time. ITS can improve hearing even if being administrated 5 weeks after onset while SMT failed after 3 weeks.

Conclusion

Patients with profound ISSNHL can obtain extra hearing recovery from salvage ITS. The earlier salvage starts, the greater the patient benefits.

Probability of clinically significant hearing recovery following salvage intratympanic steroids for sudden sensorineural hearing loss in the ‘real world’

Objective

This study aimed to determine the probability of hearing recovery in patients with idiopathic sudden sensorineural hearing loss following salvage intratympanic steroids

Method

A retrospective review of all patients receiving salvage intratympanic steroid injections for idiopathic sudden sensorineural hearing loss was performed (January 2014 to December 2019). Twenty-two patients were identified, of whom 15 met inclusion criteria. Pre- and post-treatment audiograms were compared with the unaffected ear. Hearing recovery was categorised based on American Academy of Otolaryngology Head and Neck Surgery criteria.

Results

Only 1 patient out of 15 (6.7 per cent) made a partial recovery, and the remainder were non-responders. The median duration of time between symptom onset and first salvage intratympanic steroid treatment was 52 days (range, 14–81 days). No adverse reactions were observed.

Conclusion

‘Real world’ patients with idiopathic sudden sensorineural hearing loss present differently to those in the literature. Sudden sensorineural hearing loss should be diagnosed with care and intratympanic steroid injections initiated early if considered appropriate. Patients should make an informed decision on treatment based on prognostic factors and local success rates.

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.

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.

Efficacy and safety of systemic, high-dose glucocorticoid therapy for idiopathic sudden sensorineural hearing loss : Study protocol for a three-armed, randomized, triple-blind, multicenter trial (HODOKORT)

BACKGROUND

Systemic glucocorticosteroids ("steroids") are widely used worldwide as a standard of care for primary therapy of idiopathic sudden sensorineural hearing loss (ISSHL). The German ISSHL guideline recommends high-dose steroids without evidence from randomized controlled trials (RCTs) and refers solely to retrospective cohort studies. This RCT aims to assess the efficacy (improvement in hearing) and safety (especially systemic side effects) of high-dose steroids versus standard of care (standard dose systemic steroids) for the treatment of unilateral ISSHL, when given as a primary therapy.

METHODS

The study is designed as a multicenter (approximately 40 centers), randomized, triple-blind, three-armed, parallel group, clinical trial with 312 adult patients. The interventions consist of 5 days of 250 mg/day intravenous prednisolone (intervention 1) + oral placebo, or 5 days of 40 mg/day oral dexamethasone (intervention 2) + intravenous placebo. The control intervention consists of 60 mg oral prednisolone for 5 days followed by five tapering doses + intravenous placebo. The primary efficacy endpoint is the change in hearing threshold in the three most affected contiguous frequencies between 0.25 and 8 kHz 1 month after ISSHL. Secondary endpoints include further measures of hearing improvement including speech audiometry, tinnitus, quality of life, blood pressure, and altered glucose tolerance.

DISCUSSION

There is an unmet medical need for an effective medical therapy of ISSHL. Although sensorineural hearing impairment can be partially compensated by hearing aids or cochlear implants (CI), generic hearing is better than using hearing aids or CIs. Since adverse effects of a short course of high-dose systemic corticosteroids have not been documented with good evidence, the trial will improve knowledge on possible side effects in the different treatment arms with a focus on hyperglycemia and hypertension.

TRIAL REGISTRATION

EudraCT (European Union Drug Regulating Authorities Clinical Trials Database) Nr. 2015-002602-36; Sponsor code: KKSH-127.

Hearing loss drug discovery and medicinal chemistry: Current status, challenges, and opportunities

Hearing loss is a severe high unmet need condition affecting more than 1.5 billion people globally. There are no licensed medicines for the prevention, treatment or restoration of hearing. Prosthetic devices, such as hearing aids and cochlear implants, do not restore natural hearing and users struggle with speech in the presence of background noise. Hearing loss drug discovery is immature, and small molecule approaches include repurposing existing drugs, combination therapeutics, late-stage discovery optimisation of known chemotypes for identified molecular targets of interest, phenotypic tissue screening and high-throughput cell-based screening. Hearing loss drug discovery requires the integration of specialist therapeutic area biology and otology clinical expertise. Small molecule drug discovery projects in the global clinical portfolio for hearing loss are here collated and reviewed. An overview is provided of human hearing, inner ear anatomy, inner ear delivery, types of hearing loss and hearing measurement. Small molecule experimental drugs in clinical development for hearing loss are reviewed, including their underpinning biology, discovery strategy and activities, medicinal chemistry, calculated physicochemical properties, pharmacokinetics and clinical trial status. SwissADME BOILED-Egg permeability modelling is applied to the molecules reviewed, and these results are considered. Non-small molecule hearing loss assets in clinical development are briefly noted in this review. Future opportunities in hearing loss drug discovery for human genomics and targeted protein degradation are highlighted.

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.

In silico Single-Cell Analysis of Steroid-Responsive Gene Targets in the Mammalian Cochlea

Background

Treatment of many types of hearing instability in humans, including sudden sensorineural hearing loss, Meniere's disease, and autoimmune inner ear disease, rely heavily on the utilization of corticosteroids delivered both by oral and transtympanic routes. Despite this use, there is heterogeneity in the response to treatment with corticosteroids in humans with these diseases. The mechanisms by which corticosteroids exert their effect and the cell types in which they exert their effects in the inner ear remain poorly characterized. In this study, we localize steroid-responsive genes to cochlear cell types using previously published transcriptome datasets from the mammalian cochlea.

Methods

Steroid-responsive genes were localized to specific cochlear cell types using existing transcriptome datasets from wild-type mammalian cochlea exposed to systemic and transtympanic steroids, as well as previously published single-cell and single-nucleus RNA-sequencing datasets from the mammalian cochlea. Gene ontology (GO) analysis of differentially expressed genes (DEGs) was performed using PANTHER to investigate cellular processes implicated in transtympanic vs. systemic steroid action in the cochlea.

Results

Steroid-responsive genes were localized to specific cell types and regions in the cochlea including the stria vascularis, organ of Corti, and spiral ganglion neurons (SGN). Analyses demonstrate differential prevalence of steroid-responsive genes. GO analysis demonstrated steroid-responsive DEGs in the SGN to be associated with angiogenesis, apoptosis, and cytokine-mediated anti-inflammatory pathways.

Conclusions

Single-cell and single-nucleus transcriptome datasets localize steroid-responsive genes to specific regions in the cochlea. Further study of these regionally-specific steroid-responsive genes may provide insight into the mechanisms of and clinical response to corticosteroids in diseases of hearing instability.

Efficacy and safety of standardized Ginkgo biloba L. leaves extract as an adjuvant therapy for sudden sensorineural hearing loss: A systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Ginkgo biloba L. has been used for medical purposes in China for centuries. Standardized Ginkgo biloba L. leaves extract (GBE) is a widely used botanical drug which displays a variety of pharmacological effects against sudden sensorineural hearing loss (SSNHL).

AIM OF THE STUDY

To evaluate the efficacy and safety of GBE as an adjuvant therapy, administered with corticosteroids, for the initial management of patients with SSNHL.

MATERIALS AND METHODS

We searched seven databases for randomized clinical trials (RCTs) comparing GBE plus corticosteroids with corticosteroids alone for SSNHL treatment. Data analysis was carried out by Review Manager 5.4 and Stata 16.0 software. The study was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. We subsequently evaluated the certainty of evidence using the GRADE (Grading of Recommendation Assessment, Development and Evaluation) approach.

RESULTS

A total of 11 RCTs involving 1069 patients were included. Meta-analysis indicated that the clinical cure rate (RR = 1.33, 95% CI = 1.12 to 1.58, P = 0.001) and total effective rate (RR = 1.24, 95%CI = 1.17 to 1.31, P < 0.001) in SSNHL patients receiving GBE plus corticosteroids was superior to patients receiving corticosteroids alone. After treatment, pure tone average (PTA) improvement of observation group was better than that in the control group (WMD = 10.33, 95%CI = 6.46 to 14.21, P < 0.001). The levels of whole blood high shear viscosity (WMD = 0.93, 95%CI = 0.28 to 1.59, P = 0.005), whole blood medium shear viscosity (WMD = 0.53, 95%CI = 0.11 to 0.95, P = 0.01), whole blood low shear viscosity (WMD = 1.26, 95%CI = 0.80 to 1.72, P < 0.001), plasma viscosity (WMD = 0.19, 95%CI = 0.09 to 0.30, P < 0.001) and fibrinogen (WMD = 0.80, 95%CI = 0.25 to 1.35, P = 0.004) were lower than those in the control group. There was no significant difference in the change of hematokrit between two groups (WMD = 4.23, 95%CI = -0.54 to 8.99, P = 0.08). GBE was generally well tolerated, and there was no significant difference in the incidence of adverse reactions between two groups (RR = 1.01, 95%CI = 0.57 to 1.79, P = 0.97).

CONCLUSION

The results of the current study suggested that GBE might be effective and promising as an adjuvant to corticosteroids in the initial treatment of moderate to profound SSNHL. However, the GRADE assessment indicated that the overall strength of evidence was not high. Further studies with high methodological quality and low risk of bias are needed to confirm the positive results. PROSPERO registration No. CRD 42020190113.

Effectiveness of Various Treatments for Sudden Sensorineural Hearing Loss-A Retrospective Study

(1) Background: A retrospective clinical study was conducted to compare the effectiveness of different pharmacological and non-pharmacological regimens for treating sudden sensorineural hearing loss (SSNHL). (2) Methods: Adult patients (n = 130) diagnosed with sudden sensorineural hearing loss (SSNHL) and hospitalized between 2015 and 2020 were enrolled in this study. Depending on the treatment regimen applied, patients were divided into five groups. Inclusion criteria were as follows: (i) hearing loss of sudden onset; (ii) hearing loss of at least 30 dB at three consecutive frequencies; (iii) unilateral hearing loss; (iv) age above 18 years. Exclusion criteria were as follows: (i) no follow-up audiogram; (ii) bilateral hearing loss; (iii) recognized alternative diagnosis such as tumor, disorder of inner ear fluids, infection or inflammation, autoimmune disease, malformation, hematological disease, dialysis-dependent renal failure, postdural puncture syndrome, gene-related syndrome, mitochondrial disease; and (iv) age below 18 years. (3) Results: Complete recovery was found in 14% of patients (18/130) and marked improvement was found in 6% (8/130), giving an overall success rate of 20%. The best results were obtained in the second group (i.e., patients given intratympanic glucocorticoid + prolonged orally administered glucocorticoid) where the success rate was 28%. In general, the older the patient, the smaller the improvement in hearing, a correlation that was statistically significant. (4) Conclusions: In treating SSNHL, the highest rate of hearing recovery-28%-was in the group of patients given intratympanic corticoid plus prolonged treatment with orally administered glucocorticoid.

Idiopathic Sudden Sensorineural Hearing Loss: Speech Intelligibility Deficits Following Threshold Recovery

OBJECTIVES

This retrospective study tests the hypothesis that patients who have recovered from idiopathic sudden sensorineural hearing loss (SSNHL) show deficits in word recognition tasks that cannot be entirely explained by a loss in audibility.

DESIGN

We reviewed the audiologic profile of 166 patients presenting with a unilateral SSNHL. Hearing loss severity, degree of threshold recovery, residual hearing loss, and word recognition performance were considered as outcome variables. Age, route of treatment, delay between SSNHL onset and treatment, and audiogram configuration were considered as predictor variables.

RESULTS

Severity, residual hearing loss, and recovery were highly variable across patients. While age and onset-treatment delay could not account for the severity, residual hearing loss and recovery in thresholds, configuration of the SSNHL and overall inner ear status as measured by thresholds on the contralateral ear were predictive of threshold recovery. Speech recognition performance was significantly poorer than predicted by the speech intelligibility curve derived from the patient's audiogram.

CONCLUSIONS

SSNHL is associated with (1) changes in thresholds that are consistent with ischemia and (2) speech intelligibility deficits that cannot be entirely explained by a change in hearing sensitivity.

Evaluation and comparison of the efficacy of long-acting betamethasone and dexamethasone as injections in the treatment of idiopathic sudden hearing loss

INTRODUCTION & OBJECTIVE

The aim of the present study was to determine the efficacy of long-acting betamethasone, and its comparison with Dexamethasone as an intratympanic injection in the treatment of Sudden Sensorineural Hearing Loss (SSNHL).

MATERIALS AND METHODS

Thirty-one patients who do not respond to systemic steroids and poor prognosis patients were enrolled in this study. The patients divided randomly into two groups: 1- Dexamethasone and 2- Long acting betamethasone. Dexamethasone (0.4 ml/mg) or long-acting betamethasone (0.1 ml/mg) was slowly injected (0.4 to 0.6 cc) into the superior-anterior area of the tympanic membrane as 6 injections twice a week for a total of 3 weeks. Right after the treatment and one, two and six months after completion of treatment, an audiometry was performed and compared with the pre-injection values.

RESULTS

Speech Reception Threshold (SRT) showed improvements in both groups immediately after treatment and in the follow-up period, compared to baseline. Speech Discrimination Score (SDS) also improved in both groups directly after treatment and at one-month follow-up. The hearing improvement in the Dexamethasone group was clinically better than in the Beta group, but due to the non-parametric data, it was not possible to analyze the hearing improvement process in the variable group.

CONCLUSION

According to the results obtained in this study, intratympanic corticosteroid injection in the treatment of patients with SSNHL has positive and promising results on improving hearing level.

Nuclear Factor Erythroid 2-Related Factor 2-Histone Deacetylase 2 Pathway in the Pathogenesis of Refractory Sudden Sensorineural Hearing Loss and Glucocorticoid Resistance

INTRODUCTION

A significant number of sensorineural hearing loss (SSNHL) patients had no noticeable hearing improvement after glucocorticoid (GC) treatment. In the present study, we examined expression of the nuclear factor erythroid 2-related factor 2 (NRF2) and histone deacetylase 2 (HDAC2) in peripheral blood mononuclear cells (PBMCs) of refractory SSNHL patients to study the role of NRF2-HDAC2 pathway in GC insensitivity hearing improvement after GC treatment, which is usually referred to as refractory SSNHL or GC insensitivity.

MATERIALS AND METHODS

Forty-four refractory SSNHL patients were treated by intratympanic GC infusion. Hearing was tested in all patients before and after treatment by pure tone hearing test. NRF2/HDAC2 mRNA and protein levels were examined in PBMCs of refractory SSNHL patients before and after treatment. PBMCs from healthy volunteers were used as normal controls.

RESULTS

According to the hearing improvement after treatment, patients were assigned into 2 groups: the intratympanic GC sensitive (IGCS) group (hearing recovery ≥15 dB HL) and the intratympanic GC insensitive (IGCI) group (hearing recovery <15 dB HL). Before treatment, the NRF2 mRNA level was lower in all patients than the normal control group. After treatment, NRF2 and HDAC2 mRNA and protein levels were increased in the IGCS group, while no significant change was observed in the IGCI group.

CONCLUSION

Low response of NRF2/HDAC2 proteins is associated with GC insensitivity in SSNHL. We speculate that the NRF2-HDAC2 pathway affects GC sensitivity in SSNHL patients.

Residual Perforation Risk Assessment of Intratympanic Steroids via Tympanostomy Tube Versus Transtympanic Injections

OBJECTIVES/HYPOTHESIS

To investigate the risk of residual tympanic membrane (TM) perforation after intratympanic (IT) steroidal treatment administered via transtympanic injection compared with trans-tympanostomy tube (TyT).

STUDY DESIGN

Case series, systematic review and meta analysis.

METHODS

Data were retrieved from the medical files of an original cohort of all consecutive patients with sudden sensorineural hearing loss necessitating IT steroidal treatment in a tertiary medical center between January 1, 2016 and November 20, 2020. A systematic literature search of "MEDLINE" via "PubMed," "Embase," and "Web of Science" on comparable published cases was performed and meta-analysis was established.

RESULTS

Eighteen studies describing 818 ears were included in the quantitative meta-analysis in addition to a local cohort of 140 ears. The proportion of residual TM perforation was 1.11% and 1.14% (95% confidence interval: 0.01%-3.27% and 0.028%-2.38%) in the TyT and trans-tympanic groups, respectively, suggesting no significant difference in residual TM perforation risk between these techniques.

CONCLUSION

IT steroid therapy via trans-TyT is not associated with more residual perforations than IT steroid therapy via transtympanic injections.

LEVEL OF EVIDENCE

NA Laryngoscope, 131:E2583-E2591, 2021.

Effectiveness of salvage intratympanic dexamethasone treatment for refractory sudden sensorineural hearing loss classified by audiogram patterns

BACKGROUND

Intratympanic dexamethasone is commonly conducted to treat refractory sudden sensorineural hearing loss (RSSNHL). However, no consensus has been reached on its effectiveness.

OBJECTIVES

The study aimed to evaluate the effectiveness of otoendoscope-assisted salvage intratympanic dexamethasone treatment (IDT) on RSSNHL with different audiogram patterns after failure of initial therapy.

MATERIAL AND METHODS

A total of 108 patients with unilateral RSSNHL were classified into 4 groups according to audiogram patterns. Hearing results were evaluated by pure-tone audiometry (PTA), which was performed at baseline and one month after otoendoscope-assisted salvage IDT. The effectiveness of otoendoscope-assisted salvage IDT was assessed in each group.

RESULTS

The efficiency in low-frequency, high-frequency, flat, and deaf group was 48%, 24.1%, 46.2%, 17.9%, respectively. The efficacy did not differ between the high-frequency and deaf group. Notably, the efficacy in the low-frequency and flat group was significantly higher than that in the deaf group.

CONCLUSIONS

Otoendoscope-assisted salvage IDT is a safe and effective treatment for RSSNHL. This treatment provided better results for patients with low-frequency damaged and flat curve audiogram than patients with other audiogram patterns.

SIGNIFICANCE

Audiogram patterns should be considered in the clinical management of patients with RSSHNL prior to salvage IDT.

Combination of Pulse Steroid with Intratympanic Injections in Sudden Sensorineural Hearing Loss

Introduction

Oral prednisolone was suggested as the first step to treat idiopathic sudden sensorineural hearing loss (ISSHL). This study aimed to investigate the effect of pulse therapy with methylprednisolone and intratympanic methylprednisolone, compared to traditional oral prednisolone therapy on patients with ISSHL.

Material and Methods

This randomized control trial included an experimental group receiving 500 mg intravenous methylprednisolone for three sequential days, followed by 1 mg/kg oral prednisolone for 11 days, and intratympanic Depo-Medrol four times twice a week. On the other hand, the control group received 1 mg/kg oral prednisolone for 14 days. Hearing change was assessed through pure tone audiometry. Subsequently, hearing recovery was investigated and analyzed in this study.

Result

This study was conducted on 51 patients who were divided into two groups of experimental (n=26) and control (n=25). The result revealed no significant difference between the two groups in terms of hearing improvement (P=0.28).

Conclusion

This revealed no added benefit in pulse steroids combined with intratympanic injections in cases with sudden hearing loss.

Comparison of two different intratympanic corticosteroid injection protocols as salvage treatments for idiopathic sudden sensorineural hearing loss

PURPOSE

We aimed to investigate the effect of interval length and total count of intratympanic steroid (ITS) injections in salvage treatment of patients with idiopathic sudden sensorineural hearing loss (ISSNHL).

METHODS

This retrospective case-control study included 64 patients with ISSNHL, who were treated with ITS injections as salvage therapy at a tertiary referral centre. From September 2019 to December 2020, 32 patients received up to four injections every 2-4 days (revised-protocol group). These patients were 1:1 matched to patients, who received up to three injections at 1-week intervals between January 2014 and August 2019 (initial-protocol group). Hearing outcomes of the two groups were compared.

RESULTS

Both ITS salvage treatment protocols resulted in a statistically significant hearing improvement (p < 0.05). The initial-protocol declined hearing thresholds by 12 ± 11.7 dB (p < 0.001, d = 1, P = 99%). Mean hearing function was improved by 13.4 ± 19.1 dB in the revised-protocol group [p < 0.001, d = 0.7, P = 98%]. A clinically significant hearing improvement (> 10 dB) was seen in 18 patients (58.1%) in the initial-protocol group and in 14 patients (41.9%) in the revised-protocol group. A comparison of the hearing outcomes between protocol groups revealed no statistically significant differences (p > 0.05).

CONCLUSION

These results indicate that a shorter injection interval does not lead to better hearing outcomes in ITS salvage treatment for ISSNHL. Moreover, fewer ITS injections may reduce costs, physical/mental stress of the patients and lower the risk of persistent tympanic perforations.

Therapeutic efficacy of super-high-dose steroid therapy in patients with profound sudden sensorineural hearing loss: a comparison with conventional steroid therapy

BACKGROUND

In patients with sudden sensorineural hearing loss (SSNHL), steroid therapy is an optional treatment method, but there is controversy about its dose.

OBJECTIVE

We aimed to compare the efficacy of super-high-dose steroid therapy with that of conventional steroid therapy in patients with profound SSNHL (pSSNHL).

MATERIAL AND METHODS

Fifty-two patients diagnosed with pSSNHL between March 2010 and May 2017 were divided into the following groups based on their steroid regimen: a conventional steroid regimen (prednisolone at 1.0 mg/kg/day for 10 days) was applied in Group 1, and a super-high-dose steroid regimen (prednisolone at 1.5 mg/kg/day for 14 days) was applied in Group 2. The treatment outcomes were compared between the groups at 2 and 4 weeks after the initial treatment by use of Siegel's criteria.

RESULTS

Of the 52 patients, 31 were classified into Group 1 and 21 into Group 2. When comparing the proportion of patients in complete or partial recovery by Siegel's criteria, the recovery rate was significantly higher in Group 2 than in Group 1 (19% vs 0%, p = .022 at 2 weeks; 35.7% vs 7.4%, p = 0.035 at 4 weeks).

CONCLUSIONS AND SIGNIFICANCE

Patients with pSSNHL treated using the super-high-dose steroid regimen demonstrated better recovery rates to serviceable hearing than did those treated using the conventional steroid regimen without significant complications.

Is it Beneficial to Treat Patients Presenting Three Weeks or Longer after the Onset of Sudden Sensorineural Hearing Loss?

OBJECTIVES

The accepted treatment for idiopathic sudden sensorineural hearing loss (ISSNHL) consists of oral or intratympanic steroids. The time from onset to treatment is considered as an important prognostic factor, although there is no clear cutoff point when treatment is no longer beneficial. This study aimed to assess the efficacy of treatment with oral or intratympanic steroids and carbogen, in patients presenting 21 days or later after the onset of hearing loss.

MATERIALS AND METHODS

A total of 895 patients with ISSNHL was seen in our center between 2010 and 2018. The study cohort included 103 patients treated with oral or intratympanic steroids or both with carbogen 21 days or longer after experiencing hearing loss. Retrospective analysis of files and audiometry was conducted, and pre- and post-treatment audiograms were compared. Improvement was defined by SRT (≥15 dB improvement), discrimination (≥15% improvement), or 15 dB improvement at specific frequencies (250-500, 4000-6000 Hz).

RESULTS

Hearing improvement, according to the study definition, was seen in 22.3% (23/103) of patients within the time period of the treatment. All the 23 patients had functional hearing after treatment and 16 of them returned to their baseline or normal hearing. While the time from onset of ISSNHL to treatment varied, most patients demonstrating improvement were treated 21-30 days after onset.

CONCLUSION

In this patient cohort treated late for sudden sensorineural hearing loss (SSNHL), a small but significant number of patients improved during the time of treatment. Although the lack of a control group makes it difficult to prove that the improvement resulted from the treatment, we recommend not to rule out treatment systematically in patients presenting late after ISSNHL. Additional prospective studies are warranted.

The Outcome of Prompt Concomitant Single-Dose High-Concentration Intratympanic and Tapered Low-Dose Oral Systemic Corticosteroid Treatment for Sudden Deafness

OBJECTIVES

To investigate the efficacy of prompt concomitant corticosteroid treatment with single application of high-concentration intratympanic (IT) dexamethasone and tapered low-dose systemic methylprednisolone of an idiopathic sudden sensorineural hearing loss (ISSNHL).

MATERIALS AND METHODS

Between September 2017 and September 2019, 86 adult patients met the criteria for the diagnosis of ISSNHL at baseline evaluation. The patients received immediate concomitant treatment with single high-concentration (24 mg/mL) IT dexamethasone and low-dose (48 mg) oral methylprednisolone for 1 week followed by tapered doses. Improvement in pure-tone average (PTA) and word recognition score (WRS) was determined after 1 and 6 months.

RESULTS

A total of 63 patients met the requirements for the analysis. PTA improved in 71% and WRS improved in 59% of patients with ISSNHL. PTA and WRS were statistically significantly different at different time points during the intervention (p<0.0005). Hearing improved in all measured frequencies from 125 to 8000 Hz until the second follow-up. In 65.4% of patients with tinnitus, the WRS has improved compared with 27.3% without tinnitus (p<0.05). In 69.2% of patients without vertigo, the WRS has improved compared with 41.7% with vertigo (p<0.05).

CONCLUSION

Prompt concomitant single high-concentration IT and low-dose systemic corticosteroid treatment is efficient in recovering hearing loss and speech discrimination in ISSNHL. Tinnitus positively predicts hearing outcome. Vertigo negatively predicts speech discrimination recovery.

Vestibular prognosis in idiopathic sudden sensorineural hearing loss with vestibular dysfunction treated with oral or intratympanic glucocorticoids: a protocol for randomized controlled trial

Background

Idiopathic sudden sensorineural hearing loss (ISSNHL) is a rapid-onset sensorineural hearing impairment with unclear etiology and unsatisfying treatment effects. Vestibular dysfunction has been considered as a poor indicator in the clinical manifestations and prognosis of ISSNHL, which occurred in approximately 28–57% cases. Glucocorticoids, administered through oral or intratympanic way, are currently regularly and standardly applied for ISSNHL to improve the hearing outcome. However, the vestibular prognosis of ISSNHL after routine treatments remains seldom explored. This study aims to compare the effectiveness of oral and intratympanic glucocorticoids in ISSNHL with vestibular dysfunction in terms of the pattern and trajectory of possible process of vestibular function recovery.

Methods/design

A randomized, outcome-assessor- and analyst-blinded, controlled, clinical trial (RCT) will be carried out. Seventy-two patients with ISSNHL complaining of vestibular dysfunction appearing as vertigo or imbalance will be recruited and randomized into either oral or intratympanic glucocorticoid therapy group with a 1:1 allocation ratio. The primary outcomes will be vestibular function outcomes assessed by sensory organization test, caloric test, video head impulse test, cervical vestibular evoked myogenic potential, and ocular vestibular evoked myogenic potential; the secondary outcomes include self-reported vestibular dysfunction symptoms; dizziness-related handicap, visual analogue scale for vertigo and tinnitus; and pure tone audiometry. Assessments of primary outcomes will be performed at baseline and at 4 and 8 weeks post-randomization, while assessments of secondary outcomes will be performed at baseline and 1, 2, 4, and 8 weeks post-randomization.

Discussion

Previous intervention studies of ISSNHL included only hearing outcomes, with little attention paid on the prognosis of vestibular dysfunction. This trial will be the first RCT study focusing on the progress and prognosis of vestibular dysfunction in ISSNHL. The efficacy of two commonly used therapies of glucocorticoids will be compared in both auditory and vestibular function fields, rather than in the hearing outcome alone.

Trial registration

ClinicalTrials.gov NCT03974867. Registered on 23 July 2019

Regeneration of Cochlear Synapses by Systemic Administration of a Bisphosphonate

Sensorineural hearing loss (SNHL) caused by noise exposure and attendant loss of glutamatergic synapses between cochlear spiral ganglion neurons (SGNs) and hair cells is the most common sensory deficit worldwide. We show here that systemic administration of a bisphosphonate to mice 24 h after synaptopathic noise exposure regenerated synapses between inner hair cells and SGNs and restored cochlear function. We further demonstrate that this effect is mediated by inhibition of the mevalonate pathway. These results are highly significant because they suggest that bisphosphonates could reverse cochlear synaptopathy for the treatment of SNHL.

Intratympanic steroid injection for sudden sensorineural hearing loss: Impact of injection interval on therapeutic efficacy

OBJECTIVE

To compare the effect of injection time intervals of intratympanic (IT) dexamethasone (DEX) in patients with idiopathic sudden sensorineural hearing loss (ISSNHL).

METHODS

Seventy-five adults with ISSNHL were grouped into four groups according to the IT DEX interval. In addition to concurrent oral steroid medication for two weeks, patients received IT DEX injections every 1, 2, 3, and four days, respectively. (Group 1, Group 2, Group 3, and Group 4). We evaluated the treatment outcomes according to modified criteria from "Clinical Practice Guideline: Sudden Hearing Loss" of the American Academy of Otolaryngology-Head and Neck Surgery (AAOHNS) to justify treatment success.

RESULTS

There were no significant differences in demographic and baseline audiometric data. The mean of pure tone audiometry (PTA) and speech discrimination score (SDSs) were significantly improved after oral steroid and IT DEX treatment in all four groups. Group 1 showed significantly higher improvement than Group 4 in PTA after treatment. There was a significantly higher complete recovery (CR) rate in Group 1 than Group 4.

CONCLUSION

We found a statistically significant difference in the complete hearing recovery rate and audiometric results (PTA) between the group with a daily interval of injections and the group with a four-day time interval. Therefore, daily time intervals in intratympanic steroid injection may be considered as an option for better improvement of hearing in patients with ISSNHL.

Guideline Adherence and Hearing Outcomes of Sudden Sensorineural Hearing Loss in the Military Health System

INTRODUCTION

The American Academy of Otolaryngology-Head and Neck Surgery Foundation clinical practice guideline (CPG) proposes several treatment recommendations regarding sudden sensorineural hearing loss (SSNHL). The treatments for this disorder have been controversial and remain varied. We sought to determine CPG adherence and hearing outcomes of SSNHL within the Military Health System (MHS).

MATERIALS AND METHODS

This was a retrospective case series with chart review of the MHS's electronic medical record. Patients with SSNHL (n = 112) were treated between March 1, 2012 and September 30, 2015. Clinical improvement was defined as a 20-dB improvement in pure tone averages or a 20% increase in word recognition scores.

RESULTS

Oral steroids were used in 63 (56%) patients, intratympanic (IT) steroids were utilized in 11 (10%) patients, and combination therapy was used in 38 (34%) patients. Average pure tone averages improvements with oral steroids, IT steroids, and combination therapy were 31.2 dB (95% CI, 24.4-38.0), 13.4 dB (95% CI, 0.4-29.6), and 17.3 dB (95% CI, 9.32-25.3), respectively. Average word recognition scores improvements with oral steroids, IT steroids, and combination therapy were 29.64% (95% CI, 19.5-39.7), 14.43% (95% CI, -8.32 to 45.3), and 18.48% (95% CI, 5.48-31.5), respectively. Clinical improvements with oral steroids, IT steroids, and combination therapy were 65, 46, and 50%, respectively.

CONCLUSION

The MHS is uniquely positioned to evaluate adherence to CPGs on a national and international level given the robust and standardized electronic medical record. Areas identified for improvement include more timely initiation of treatment, standardization of IT steroid dosing, more accurate coding for diagnosis and treatment, and standardization of audiology evaluation.

Intratympanic injection of dexamethasone 4 mg/mL versus 10 mg/mL for management of idiopathic sudden sensorineural hearing loss

Background

The aim of this study was to determine whether different concentrations of intratympanic (IT) injection of dexamethasone at a dose of 4 and 10 mg/mL have an effect on hearing outcomes in patients with idiopathic sudden sensorineural hearing loss (ISSNHL).

Results

Our study was conducted on 30 adult patients with unilateral ISSNHL who failed to respond or with contraindications to systemic steroids. Patients were categorized into two groups; each one included 15 patients. IT injection of 4 mg/mL dexamethasone was done in one group (IT dexamethasone (Dex) 4 mg/mL), while 10 mg/mL dexamethasone was administered intratympanically in the other group (IT Dex 10 mg/mL). IT injection was performed twice weekly for two successive weeks. PTA thresholds were assessed at 0.5, 1, 2 and 4 kHz before and 1 month after the treatment.

In the group with IT Dex 10 mg/mL, the average PTA improved significantly from 75.50 ± 12.59 to 49 ± 24.04 dB with an average gain of 26.50 ± 14.25 (p = 0.0007). In the group with IT Dex 4 mg/mL, there was a significant change of PTA from a pretreatment value of 76.92 ± 11.89 dB to a post-treatment value of 59.27 ± 92.10 dB with an average gain of 17.65 ± 8.36 dB.

A comparison of the post-treatment gain of PTA in both groups showed better improvement of hearing in a group treated by IT Dex 10 mg/mL compared with 4 mg/mL.

Conclusion

This study demonstrated that IT injection of dexamethasone at a dose of 10 mg/ml was associated with better hearing outcomes compared with 4 mg/mL for the treatment of ISSNHL.

Methodological Quality of Systematic Reviews and Meta-analyses Published in High-Impact Otolaryngology Journals

OBJECTIVE

To assess the methodological quality of intervention-focused systematic reviews (SRs) and meta-analyses (MAs) published in high-impact otolaryngology journals.

DATA SOURCES

Ovid Medline, Embase, and Cochrane Library.

REVIEW METHODS

A comprehensive search was performed for SR and MA citations from 2012 to 2017 in the 10 highest impact factor otolaryngology journals. Abstracts were screened to identify published manuscripts in which the authors indicated clearly that they were performing an SR or MA. Applying a modified typology of reviews, 4 reviewers characterized the review type as SR, MA, or another review type. A simplified version of the AMSTAR 2 (A MeaSurement Tool to Assess systematic Reviews 2) tool was used to assess the reporting and methodological quality of the SRs and MAs that were focused on interventions.

RESULTS

Search and abstract screening generated 499 manuscripts that identified themselves as performing an SR or MA. A substantial number (85/499, 17%) were review types other than SRs or MAs, including 34 (7%) that were literature reviews. In total, 236 SRs and MAs focused on interventions. Over 50% of these SRs and MAs had weaknesses in at least 3 of the 16 items in the AMSTAR 2, and over 40% had weaknesses in at least 2 of the 7 critical domains. Ninety-nine percent of SRs and MAs provided critically low confidence in the results of the reviews.

CONCLUSION

Intervention-focused SRs and MAs published in high-impact otolaryngology journals have important methodological limitations that diminish confidence in the results of these reviews.

Efficacy and Safety of AM-111 in the Treatment of Acute Unilateral Sudden Deafness-A Double-blind, Randomized, Placebo-controlled Phase 3 Study

Objective:

To confirm the efficacy and safety of AM-111 (brimapitide), a cell-penetrating c-Jun N-terminal Kinase (JNK) inhibitor, in patients suffering from severe to profound acute unilateral idiopathic sudden sensorineural hearing loss (ISSNHL).

Study design:

Prospective, double-blind, randomized, placebo-controlled phase 3 study with follow-up visits on Days 3, 7, 28, and 91.

Setting:

Fifty-one European and Asian sites (tertiary referral centers, private ENT practices).

Patients:

Two hundred fifty-six patients aged 18 to 65 years presenting within 72 hours following ISSNHL onset with mean hearing loss ≥ 40 dB and mean threshold ≥ 60 dB at the 3 worst affected contiguous test frequencies.

Interventions:

Single-dose intratympanic injection of AM-111 (0.4 or 0.8 mg/ml) or placebo; oral prednisolone as reserve therapy if hearing improvement < 10 dB at Day 7.

Main outcome measures:

Hearing improvement to Day 28 was the primary efficacy endpoint; complete hearing recovery, frequency of reserve therapy used, complete tinnitus remission, improvement in word recognition were secondary endpoints. Safety was evaluated by the frequency of clinically relevant hearing deterioration and adverse events.

Results:

While the primary efficacy endpoint was not met in the overall study population, post-hoc analysis showed a clinically relevant and nominally significant treatment effect for AM-111 0.4 mg/ml in patients with profound ISSNHL. The study drug and the administration procedure were well tolerated.

Conclusions:

AM-111 provides effective otoprotection in case of profound ISSNHL. Activation of the JNK stress kinase, AM-111's pharmacologic target, seems to set in only following pronounced acute cochlear injury associated with large hearing threshold shifts.

Adjuvant Migraine Medications in the Treatment of Sudden Sensorineural Hearing Loss

OBJECTIVES/HYPOTHESIS

To examine the hearing outcomes of patients with sudden sensorineural hearing loss (SSNHL) treated with oral and intratympanic (IT) steroid only or a combination of steroid and migraine treatment. Our hypothesis was that adjuvant migraine medications may improve outcomes in SSNHL.

METHODS

A retrospective chart review at a tertiary otology center was conducted to identify patients with SSNHL who received oral steroid and IT dexamethasone injection(s) with or without migraine medications (a combination of nortriptyline and topiramate).

RESULTS

A total of 47 patients received oral steroid and IT dexamethasone injection(s) only, and 46 patients received oral steroid and IT dexamethasone injection(s) as well as migraine lifestyle changes plus a combination of nortriptyline and topiramate. There were no significant differences in demographics and baseline audiometric data between the two groups. Both groups demonstrated improvements in pure tone average (PTA) and hearing thresholds at 250 Hz and 8000 Hz posttreatment. However, compared to steroid-only group, the adjuvant migraine medications group had significantly greater improvements in hearing thresholds at the lower frequencies (250 Hz, 500 Hz, 1000 Hz). Patients in the latter cohort also had greater improvement in PTA (P = .01) and received fewer IT injections (P = .04) PTA improvement of ≥ 10 dB was observed in 36 patients (78%) in the adjuvant migraine medications group and 22 patients (46%) in the control group (P < .001).

CONCLUSION

In multimodal treatment of SSNHL, supplementing oral and IT steroid with migraine medications may result in greater improvements in lower frequency hearing thresholds and PTA. Furthermore, adjuvant migraine treatment can lead to decrease in number of IT injections, thus reducing procedure-related risks and complications.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:E283-E288, 2021.

Clinical Practice Guideline: Sudden Hearing Loss (Update)

OBJECTIVE

Sudden hearing loss is a frightening symptom that often prompts an urgent or emergent visit to a health care provider. It is frequently but not universally accompanied by tinnitus and/or vertigo. Sudden sensorineural hearing loss affects 5 to 27 per 100,000 people annually, with about 66,000 new cases per year in the United States. This guideline update provides evidence-based recommendations for the diagnosis, management, and follow-up of patients who present with sudden hearing loss. It focuses on sudden sensorineural hearing loss in adult patients aged ≥18 years and primarily on those with idiopathic sudden sensorineural hearing loss. Prompt recognition and management of sudden sensorineural hearing loss may improve hearing recovery and patient quality of life. The guideline update is intended for all clinicians who diagnose or manage adult patients who present with sudden hearing loss.

PURPOSE

The purpose of this guideline update is to provide clinicians with evidence-based recommendations in evaluating patients with sudden hearing loss and sudden sensorineural hearing loss, with particular emphasis on managing idiopathic sudden sensorineural hearing loss. The guideline update group recognized that patients enter the health care system with sudden hearing loss as a nonspecific primary complaint. Therefore, the initial recommendations of this guideline update address distinguishing sensorineural hearing loss from conductive hearing loss at the time of presentation with hearing loss. They also clarify the need to identify rare, nonidiopathic sudden sensorineural hearing loss to help separate those patients from those with idiopathic sudden sensorineural hearing loss, who are the target population for the therapeutic interventions that make up the bulk of the guideline update. By focusing on opportunities for quality improvement, this guideline should improve diagnostic accuracy, facilitate prompt intervention, decrease variations in management, reduce unnecessary tests and imaging procedures, and improve hearing and rehabilitative outcomes for affected patients.

METHODS

Consistent with the American Academy of Otolaryngology-Head and Neck Surgery Foundation's "Clinical Practice Guideline Development Manual, Third Edition" (Rosenfeld et al. Otolaryngol Head Neck Surg. 2013;148[1]:S1-S55), the guideline update group was convened with representation from the disciplines of otolaryngology-head and neck surgery, otology, neurotology, family medicine, audiology, emergency medicine, neurology, radiology, advanced practice nursing, and consumer advocacy. A systematic review of the literature was performed, and the prior clinical practice guideline on sudden hearing loss was reviewed in detail. Key Action Statements (KASs) were updated with new literature, and evidence profiles were brought up to the current standard. Research needs identified in the original clinical practice guideline and data addressing them were reviewed. Current research needs were identified and delineated.

RESULTS

The guideline update group made strong recommendations for the following: (KAS 1) Clinicians should distinguish sensorineural hearing loss from conductive hearing loss when a patient first presents with sudden hearing loss. (KAS 7) Clinicians should educate patients with sudden sensorineural hearing loss about the natural history of the condition, the benefits and risks of medical interventions, and the limitations of existing evidence regarding efficacy. (KAS 13) Clinicians should counsel patients with sudden sensorineural hearing loss who have residual hearing loss and/or tinnitus about the possible benefits of audiologic rehabilitation and other supportive measures. These strong recommendations were modified from the initial clinical practice guideline for clarity and timing of intervention. The guideline update group made strong recommendations against the following: (KAS 3) Clinicians should not order routine computed tomography of the head in the initial evaluation of a patient with presumptive sudden sensorineural hearing loss. (KAS 5) Clinicians should not obtain routine laboratory tests in patients with sudden sensorineural hearing loss. (KAS 11) Clinicians should not routinely prescribe antivirals, thrombolytics, vasodilators, or vasoactive substances to patients with sudden sensorineural hearing loss. The guideline update group made recommendations for the following: (KAS 2) Clinicians should assess patients with presumptive sudden sensorineural hearing loss through history and physical examination for bilateral sudden hearing loss, recurrent episodes of sudden hearing loss, and/or focal neurologic findings. (KAS 4) In patients with sudden hearing loss, clinicians should obtain, or refer to a clinician who can obtain, audiometry as soon as possible (within 14 days of symptom onset) to confirm the diagnosis of sudden sensorineural hearing loss. (KAS 6) Clinicians should evaluate patients with sudden sensorineural hearing loss for retrocochlear pathology by obtaining magnetic resonance imaging or auditory brainstem response. (KAS 10) Clinicians should offer, or refer to a clinician who can offer, intratympanic steroid therapy when patients have incomplete recovery from sudden sensorineural hearing loss 2 to 6 weeks after onset of symptoms. (KAS 12) Clinicians should obtain follow-up audiometric evaluation for patients with sudden sensorineural hearing loss at the conclusion of treatment and within 6 months of completion of treatment. These recommendations were clarified in terms of timing of intervention and audiometry and method of retrocochlear workup. The guideline update group offered the following KASs as options: (KAS 8) Clinicians may offer corticosteroids as initial therapy to patients with sudden sensorineural hearing loss within 2 weeks of symptom onset. (KAS 9a) Clinicians may offer, or refer to a clinician who can offer, hyperbaric oxygen therapy combined with steroid therapy within 2 weeks of onset of sudden sensorineural hearing loss. (KAS 9b) Clinicians may offer, or refer to a clinician who can offer, hyperbaric oxygen therapy combined with steroid therapy as salvage therapy within 1 month of onset of sudden sensorineural hearing loss.

DIFFERENCES FROM PRIOR GUIDELINE

Incorporation of new evidence profiles to include quality improvement opportunities, confidence in the evidence, and differences of opinion Included 10 clinical practice guidelines, 29 new systematic reviews, and 36 new randomized controlled trials Highlights the urgency of evaluation and initiation of treatment, if treatment is offered, by emphasizing the time from symptom occurrence Clarification of terminology by changing potentially unclear statements; use of the term sudden sensorineural hearing loss to mean idiopathic sudden sensorineural hearing loss to emphasize that >90% of sudden sensorineural hearing loss is idiopathic sudden sensorineural hearing loss and to avoid confusion in nomenclature for the reader Changes to the KASs from the original guideline: KAS 1-When a patient first presents with sudden hearing loss, conductive hearing loss should be distinguished from sensorineural. KAS 2-The utility of history and physical examination when assessing for modifying factors is emphasized. KAS 3-The word "routine" is added to clarify that this statement addresses nontargeted head computerized tomography scan that is often ordered in the emergency room setting for patients presenting with sudden hearing loss. It does not refer to targeted scans, such as temporal bone computerized tomography scan, to assess for temporal bone pathology. KAS 4-The importance of audiometric confirmation of hearing status as soon as possible and within 14 days of symptom onset is emphasized. KAS 5-New studies were added to confirm the lack of benefit of nontargeted laboratory testing in sudden sensorineural hearing loss. KAS 6-Audiometric follow-up is excluded as a reasonable workup for retrocochlear pathology. Magnetic resonance imaging, computerized tomography scan if magnetic resonance imaging cannot be done, and, secondarily, auditory brainstem response evaluation are the modalities recommended. A time frame for such testing is not specified, nor is it specified which clinician should be ordering this workup; however, it is implied that it would be the general or subspecialty otolaryngologist. KAS 7-The importance of shared decision making is highlighted, and salient points are emphasized. KAS 8-The option for corticosteroid intervention within 2 weeks of symptom onset is emphasized. KAS 9-Changed to KAS 9A and 9B. Hyperbaric oxygen therapy remains an option but only when combined with steroid therapy for either initial treatment (9A) or salvage therapy (9B). The timing of initial therapy is within 2 weeks of onset, and that of salvage therapy is within 1 month of onset of sudden sensorineural hearing loss. KAS 10-Intratympanic steroid therapy for salvage is recommended within 2 to 6 weeks following onset of sudden sensorineural hearing loss. The time to treatment is defined and emphasized. KAS 11-Antioxidants were removed from the list of interventions that the clinical practice guideline recommends against using. KAS 12-Follow-up audiometry at conclusion of treatment and also within 6 months posttreatment is added. KAS 13-This statement on audiologic rehabilitation includes patients who have residual hearing loss and/or tinnitus who may benefit from treatment. Addition of an algorithm outlining KASs Enhanced emphasis on patient education and shared decision making with tools provided to assist in same.

Treatment algorithm for idiopathic sudden sensorineural hearing loss based on epidemiologic surveys of a large Japanese cohort

Background: To date, there have been few conventional algorithms for the treatment of idiopathic sudden sensorineural hearing loss (SSNHL), as there have been only limited reports with high evidence levels.Objectives: To propose an evidence- and trend-based treatment algorithm for SSNHL.Methods: We referred not only to the evidence for each treatment, but also to trends related to treatment selection in Japan based on epidemiologic surveys, and considered the balance of the advantages and disadvantages with regard to each patient's condition.Results: We propose an algorithm that begins with the grade of SSNHL severity as the prognosis of SSNHL is strongly related to the severity of hearing loss. We selected systemic corticosteroid therapy as the first-line therapy, and Intra-tympanic corticosteroid therapy as salvage therapy. We also proposed the use of prostaglandin E1 with corticosteroids for the treatment of SSNHL patients with severe hearing loss. According to the data obtained from an epidemiologic survey, we decided time limits for the application of each treatment.Conclusion: An algorithm for the treatment for SSNHL is presented according to the results of epidemiologic surveys in Japan. It is expected that this algorithm can provide a guide to choosing the suitable treatment for SSNHL patients.

5-HT3 Receptor Antagonists in Neurologic and Neuropsychiatric Disorders: The Iceberg Still Lies beneath the Surface

5-HT₃ receptor antagonists, first introduced to the market in the mid-1980s, are proven efficient agents to counteract chemotherapy-induced emesis. Nonetheless, recent investigations have shed light on unappreciated dimensions of this class of compounds in conditions with an immunoinflammatory component as well as in neurologic and psychiatric disorders. The promising findings from multiple studies have unveiled several beneficial effects of these compounds in multiple sclerosis, stroke, Alzheimer disease, and Parkinson disease. Reports continue to uncover important roles for 5-HT₃ receptors in the physiopathology of neuropsychiatric disorders, including depression, anxiety, drug abuse, and schizophrenia. This review addresses the potential of 5-HT₃ receptor antagonists in neurology- and neuropsychiatry-related disorders. The broad therapeutic window and high compliance observed with these agents position them as suitable prototypes for the development of novel pharmacotherapeutics with higher efficacy and fewer adverse effects.

Hearing Changes After Intratympanic Steroids for Secondary (Salvage) Therapy of Sudden Hearing Loss: A Meta-Analysis Using Mathematical Simulations of Drug Delivery Protocols

OBJECTIVE

The use of glucocorticoids for secondary (salvage/rescue) therapy of idiopathic sudden hearing loss (ISSHL), including controlled and uncontrolled studies with intratympanic injections or continuous, catheter mediated applications, were evaluated by means of a meta-analysis in an attempt to define optimal local drug delivery protocols for ISSHL.

STUDY DESIGN

A total of 30 studies with 33 treatment groups between January 2000 and June 2014 were selected based on sufficiently detailed description of application protocols. Cochlear drug levels were calculated by a validated computer model of drug dispersion in the inner ear fluids based on the concentration and volume of glucocorticoids applied, the time drug remained in the middle ear, and on the specific timing of injections. Various factors were compared with hearing outcome, including baseline data, individual parameters of the application protocols, calculated peak concentration (Cmax), and total dose (area under the curve, AUC).

RESULTS

There was no dependence of hearing outcome on individual parameters of the application protocol, Cmax or AUC. Hearing gain and final hearing thresholds were independent of treatment delay.

CONCLUSION

Based on the available data from uncontrolled and controlled randomized and non-randomized studies no clear recommendation can be made so far for a specific application protocol for either primary or secondary (salvage) intratympanic steroid treatment in patients with ISSHL. For meta-analyses, change in pure tone average (PTA) may not be an adequate outcome parameter to assess effectiveness of the intervention especially with inhomogeneity of patient populations. Final PTA might provide a better outcome parameter.

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice - Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Eighth Special Issue

The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating and categorizing indications for the evidence-based use of therapeutic apheresis (TA) in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Eighth Edition of the JCA Special Issue continues to maintain this methodology and rigor in order to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Eighth Edition, like its predecessor, continues to apply the category and grading system definitions in fact sheets. The general layout and concept of a fact sheet that was introduced in the Fourth Edition, has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of TA in a specific disease entity or medical condition. The Eighth Edition comprises 84 fact sheets for relevant diseases and medical conditions, with 157 graded and categorized indications and/or TA modalities. The Eighth Edition of the JCA Special Issue seeks to continue to serve as a key resource that guides the utilization of TA in the treatment of human disease.

Evidence Supporting the Hypothesis That Inflammation-Induced Vasospasm Is Involved in the Pathogenesis of Acquired Sensorineural Hearing Loss

Sensorineural hearing loss is mainly acquired and affects an estimated 1.3 billion humans worldwide. It is related to aging, noise, infection, ototoxic drugs, and genetic defects. It is essential to identify reversible and preventable causes to be able to reduce the burden of this disease. Inflammation is involved in most causes and leads to tissue injury through vasospasm-associated ischemia. Vasospasm is reversible. This review summarized evidence linking inflammation-induced vasospasm to several forms of acquired sensorineural hearing loss. The link between vasospasm and sensorineural hearing loss is directly evident in subarachnoid haemorrhage, which involves the release of vasoconstriction-inducing cytokines like interleukin-1, endothelin-1, and tumour necrosis factor. These proinflammatory cytokines can also be released in response to infection, autoimmune disease, and acute or chronically increased inflammation in the ageing organism as in presbyacusis or in noise-induced cochlear injury. Evidence of vasospasm and hearing loss has also been discovered in bacterial meningitis and brain injury. Resolution of inflammation-induced vasospasm has been associated with improvement of hearing in autoimmune diseases involving overproduction of interleukin-1 from inflammasomes. There is mainly indirect evidence for vasospasm-associated sensorineural hearing loss in most forms of systemic or injury- or infection-induced local vascular inflammation. This opens up avenues in prevention and treatment of vascular and systemic inflammation as well as vasospasm itself as a way to prevent and treat most forms of acquired sensorineural hearing loss. Future research needs to investigate interventions antagonising vasospasm and vasospasm-inducing proinflammatory cytokines and their production in randomised controlled trials of prevention and treatment of acquired sensorineural hearing loss. Prime candidates for interventions are hereby inflammasome inhibitors and vasospasm-reducing drugs like nitric oxide donors, rho-kinase inhibitors, and magnesium which have the potential to reduce sensorineural hearing loss in meningitis, exposure to noise, brain injury, arteriosclerosis, and advanced age-related and autoimmune disease-related inflammation.

Medicines discovery for auditory disorders: Challenges for industry

Currently, no approved medicines are available for the prevention or treatment of hearing loss. Pharmaceutical industry productivity across all therapeutic indications has historically been disappointing, with a 90% chance of failure in delivering a marketed drug after entering clinical evaluation. To address these failings, initiatives have been applied in the three cornerstones of medicine discovery: target selection, clinical candidate selection, and clinical studies. These changes aimed to enable data-informed decisions on the translation of preclinical observations into a safe, clinically effective medicine by ensuring the best biological target is selected, the most appropriate chemical entity is advanced, and that the clinical studies enroll the correct patients. The specific underlying pathologies need to be known to allow appropriate patient selection, so improved diagnostics are required, as are methodologies for measuring in the inner ear target engagement, drug delivery and pharmacokinetics. The different therapeutic strategies of protecting hearing or preventing hearing loss versus restoring hearing are reviewed along with potential treatments for tinnitus. Examples of current investigational drugs are discussed to highlight key challenges in drug discovery and the learnings being applied to improve the probability of success of launching a marketed medicine.

Prediction of hearing recovery in sudden deafness treated with intratympanic steroids

The present study aims to obtain a probability model allowing prediction of auditory recovery in patients affected by sudden sensorineural hearing loss treated exclusively with intratympanic steroids. A monocentric retrospective chart review of 381 patients has been performed. A Probit model was used to investigate the correlation between the success of treatment (marked or total recovery according to Furuashi’s criteria) and the delay between onset of disease and beginning of therapy. The age of patients and audiometric curve shapes were included in the analysis. The results show that delay is negatively correlated with variable success. Considering the entire sample, each day of delay decreases the probability of success by 3%. The prediction model shows that for each day that passes from the onset of the disease the probability of success declines in absence of the medical treatment, hence we conclude that early treatment is strongly recommended.

Glucococorticoid receptor activation exacerbates aminoglycoside-induced damage to the zebrafish lateral line

Aminoglycoside antibiotics have potent antibacterial properties but cause hearing loss in up to 25% of patients. These drugs are commonly administered in patients with high glucocorticoid stress hormone levels and can be combined with exogenous glucocorticoid treatment. However, the interaction of stress and aminoglycoside-induced hearing loss has not been fully explored. In this study, we investigated the effect of the glucocorticoid stress hormone cortisol on hair cells in the zebrafish lateral line as an important step toward understanding how physiological stressors modulate hair cell survival. We found that 24-hr cortisol incubation sensitized hair cells to neomycin damage. Pharmacological and genetic manipulation demonstrates that sensitization depended on the action of the glucocorticoid receptor but not the mineralocorticoid receptor. Blocking endogenous cortisol production reduced hair cell susceptibility to neomycin, further evidence that glucocorticoids modulate aminoglycoside ototoxicity. Glucocorticoid transcriptional activity was apparent in lateral line hair cells, suggesting a direct action of cortisol in these aminoglycoside-sensitive cells. Our work shows that the stress hormone cortisol can increase hair cell sensitivity to aminoglycoside damage, which highlights the importance of recognizing stress and the impacts of glucocorticoid signaling in both ototoxicity research and clinical practice.

Efficacy of combination therapy in adolescent and adult patients with total-deafness sudden sensorineural hearing loss

BACKGROUND

Combination therapy is the first-line option for total-deafness sudden sensorineural hearing loss (SSNHL). Age may act as a crucial prognostic factor.

OBJECTIVE

The aim of this study was to compare efficacy of combination therapy between adolescent and adult patients with total-deafness SSNHL.

MATERIALS AND METHODS

Twenty-five adolescent patients (adolescent group) and 106 adult patients (adult group) with total-deafness SSNHL were recruited. All the recruited patients underwent initial treatment with batroxobin, methylprednisolone, and gastrodin. After 10-day treatment, hearing outcomes were determined by pure-tone average measured by audiometry. Moreover, the total effective rates in the hearing recovery and improvement of tinnitus were calculated.

RESULTS

There existed no significant difference between two groups in the total effective rate of the hearing recovery (p = .110). However, a significant difference was found in the total effective rate of improvement of tinnitus between two groups (p = .016). Both adolescent and adult patients could receive the optimal hearing gains at 500 Hz (20.2 ± 13.3 and 23.1 ± 13.9dB, respectively), followed by those at 1000 Hz (18.8 ± 12.5 and 22.7 ± 14.8dB, respectively). Yet, adult patients could get better hearing gains only at 500 Hz than adolescent patients (p = .02).

CONCLUSION

Compared with adult patients, adolescent patients with total-deafness SSNHL undergoing combination therapy may be less likely to have hearing recovery and the improvement of tinnitus.

Intratympanic Steroid Use for Sudden Sensorineural Hearing Loss: Current Otolaryngology Practice

OBJECTIVE

To investigate the current practice of intratympanic steroid (ITS) injection for sudden sensorineural hearing loss (SSNHL) in the United Kingdom and link the data with data from the United States and continental Europe.

METHODS

A survey of 21 questions was distributed to members of the British Society of Otology using an online survey platform via ENT UK. Data obtained from UK otolaryngologists (n = 171) were integrated with previously published data from other countries, including the United States (n = 63) and continental Europe (n = 908).

RESULTS

In the United Kingdom, 62% of responding otolaryngologists use ITS injection for SSNHL, while 38% do not. Of those using ITS, 59% use it as first-line treatment, either using it in conjunction with oral steroids (51%) or using it as monotherapy (8%). Of those that use ITS, a majority (83%) use it as salvage therapy when primary treatment with systemic steroids has failed, and similar results are found in the continental Europe and US surveys. The most commonly used preparation is dexamethasone. Responses to questions regarding treatment regimes used are enlightening and show considerable variation in the treatment regimes used within and between countries.

CONCLUSIONS

There is a wide variation in practice with regards to ITS for SSNHL hearing loss in the United Kingdom, United States, and continental Europe. In the absence of protocols or definitive guidance from published literature, knowledge of contemporary practice may help guide or encourage reevaluation of clinical practice and will help guide the design of future clinical trials.