Intratympanic steroids as a salvage treatment for sudden sensorineural hearing loss? A meta-analysis. Eur Arch Otorhinolaryngol. 2015;272:2777-2782. [PMID: 25217083 DOI: 10.1007/s00405-014-3288-8]

Perilymph sampling in Mongolian gerbil, technical note and procedure evaluation

OBJECTIVE

The aim of this study is to detail and evaluate the surgical procedure for perilymph sampling from the cochlear apex in the Mongolian gerbil.

DESIGN

Perilymph sampling from the cochlear apex was performed one to three time in 12 male gerbils aged 8 to 12 months via the submandibular route. 11 of them were previously implanted with intracochlear implants loaded with dexamethasone and placed in the scala tympani, the 12th was used to collect control samples. The procedure was performed under general gas anesthesia, with head support, by a submandibular approach. After opening the bulla and sacrificing the external and middle ears, the cochlea was exposed and perilymph sampled. Macroscopic features of perilymph samples were reported before an HPLC-MS/MS assay to detect and quantify dexamethasone. Some cochleae were then harvested, immunostained and cleared to study fibrosis formation along the labyrinth and evaluate the consequences of multiple sampling procedures.

RESULTS

The perilymph sampling procedure was technically difficult and required experimenter training. The procedure was well tolerated by the animals. One drawback of this technique in our gerbil model was the need to sacrifice the external ear, eardrum and ossicular chain to allow sufficient exposure for a quality procedure. Our technique enabled the collection of perilymph samples of the desired volume. Most of our samples were contaminated by bleeding from the otic capsule bone secondary to the cochleostomy. Nevertheless, HPLC-MS/MS analyses which successfully found dexamethasone in the perilymph of implanted gerbils, confirmed that our method was suitable for pharmacokinetic analyses. The occurrence of areas of fibrosis in the labyrinth after a sampling procedure compromises the quality and reliability of subsequent samples from the same animal.

CONCLUSION

The Mongolian gerbil is an animal model that can be used to collect perilymph from the cochlear apex to perform pharmacokinetic studies. The number of samples taken from a single animal must be limited to one.

Comparison of side effects of different steroids used in intratympanic injections

OBJECTIVES

This study aimed to compare the side effects of different steroids used in the intratympanic injections (IT).

METHODS

One hundred and sixty patients diagnosed with sudden sensorineural hearing loss and undergoing IT were assigned to four groups based on the type or concentration of steroids administered (Group DM5: 5 mg/ml Dexamethasone sodium phosphate; Group DM10: 10 mg/ml Dexamethasone sodium phosphate; Group MP: 40 mg/ml Methylprednisolone sodium succinate; Group BM: 4 mg/ml Betamethasone sodium phosphate). Each group comprised 40 patients, and all participants received IT six times. The study assessed and compared the degrees and duration of pain, dizziness, and tympanic membrane damage following IT. Patients were asked to report the pain they felt using the numeric rating scale (NRS).

RESULTS

NRS scores for pain after IT showed significant differences among the four groups (p < 0.001). The average NRS scores for pain in each group were as follows: Group DM5: 1.53 ± 1.04; Group DM10: 1.45 ± 1.30; Group MP: 4.33 ± 2.22; Group BM: 6.03 ± 1.46. The durations of pain after IT also exhibited significant differences among the four groups (p < 0.001), with the longest duration observed in Group MP at 31.93 ± 15.20 min.

CONCLUSION

Different types of steroids could lead to varying degrees of pain when used in IT. Betamethasone could cause the most severe pain, and methylprednisolone could result in the longest duration of pain.

[Role of intratympanic glucocorticoid treatment in sudden hearing loss]

Idiopathic sudden sensorineural hearing loss (ISSNHL) is one of the most common diseases in otolaryngology. Its etiology remains unknown. Furthermore, there is only a low level of evidence for the efficacy of established treatment modalities. In addition to systemic glucocorticoids, intratympanic corticosteroid treatment (ICT) has become increasingly important for treatment of ISSNHL. Different application strategies and treatment regimens have been described; however, uniform standards do not yet exist. ICT may be used for primary treatment as well as salvage therapy. Current data from meta-analyses show no benefit of intratympanic versus systemic primary therapy for sudden hearing loss (moderate evidence) but suggest a benefit of intratympanic secondary treatment over no treatment or placebo (high effect size, low evidence). Regarding combination of systemic and local glucocorticoid therapy in primary treatment of hearing loss, there may be a small benefit over systemic treatment alone (low effect size, low evidence).

Therapeutic effect of intraperitoneal dexamethasone on noise-induced permanent threshold shift in mice model

The purpose of the study was to which investigate whether dexamethasone, which has anti-inflammatory and immune response suppression roles, could treat noise-induced hearing loss caused by damage to hair cells in the cochlea. The experiment used 8-week-old CBA mice exposed to white noise at an intensity of 110 dB SPL for 2 h, with hearing loss confirmed by the auditory brainstem response test. Dexamethasone was administered by intraperitoneal injection for 5 days, and the therapeutic effect was investigated for 3 weeks. The experimental groups were 3 mg/kg of dexamethasone (3 mpk) and 10 mg/kg of dexamethasone (10 mpk), and the control group was a saline-administered group. The results showed that compared to the control group, the hearing threshold value was recovered by 10 dB SPL compared to the saline group from the 14th day in the 3 mpk group. In the 10 mpk group, thresholds were recovered from the 7th day compared to the saline group. This difference was similar at 4 kHz, and in the case of the 10 mpk group, the threshold was recovered by 20 dB SPL compared to the saline group. The study also confirmed the restoration of nerve cell activity and showed a recovery effect of about 20 µV in the amplitude value change in the 10 mpk group. In conclusion, the study suggests that dexamethasone has a therapeutic effect for noise-induced hearing loss by increasing the activity of nerve cells and showing a recovery effect from hair cells damaged by noise.

Primary versus salvage intratympanic steroid treatment for idiopathic sudden sensorineural hearing loss

Objective

The objective of this research is to compare primary and salvage intratympanic (IT) steroid treatments in terms of hearing outcomes in patients with idiopathic sudden sensorineural hearing loss (ISSNHL).

Methods

The patients were randomized into two (primary and salvage) groups. Both groups received systemic steroid treatment for 2 weeks. The primary group also received IT dexamethasone injection three times during the treatment period, whereas the salvage group received IT dexamethasone injection only if no or slight recovery was noted at the 2-week follow-up. If needed, salvage steroid injection was administered three times during the following 2 weeks. Hearing recovery was analyzed according to the modified American Academy of Otolaryngology-Head and Neck Surgery criteria.

Results

The degrees of hearing improvement at the 3-month follow-up were similar in the two groups. Compared with baseline, the pure-tone average values and speech discrimination scores improved by 38.45 ± 21.95 dB HL and 34.32% ± 30.55%, respectively, in the primary group and 36.80 ± 22.33 dB HL and 31.87% ± 27.88%, respectively, in the salvage group (p = .762 and .659, respectively). In addition, the complete or partial hearing recovery rates were also similar in the primary and salvage groups (67.7% vs. 73.3%, respectively; p = .780). In the salvage group, 18 patients required no IT steroid injection because they recovered after systemic steroid treatment.

Conclusion

Primary and salvage IT steroid treatments for ISSNHL led to similar outcomes. In summary, salvage IT steroid injection is recommended for patients with ISSNHL patients to prevent unnecessary IT injection.

Level of evidence

2.

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

Objectives

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

Methods

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

Results

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

Conclusion

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

Clinical trial registration

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

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

Introduction

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

Methods

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

Results

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

Conclusion

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

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.

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.

Intratympanic Versus Systemic Steroid Therapy for Idiopathic Sudden Hearing Loss: A Systematic Review and Meta-Analysis

Idiopathic sudden sensorineural hearing loss (ISSHL) is a common condition characterized by hearing threshold reduction, most often of unknown causes. The patient experiences a sudden reduction of the hearing threshold in one or both ears. Steroids are the mainstream of the treatment. This study aims to investigate the effectiveness of intratympanic steroid administration compared with systemic administration and the combination of the two steroid treatments in the hearing recovery of patients with idiopathic sudden sensorineural hearing loss. We searched electronic databases such as PubMed, ScienceDirect, CINAHL, Cochrane (Central), Ovid, and Medline from August 31, 2021, to November 31, 2021, and from February 5 to 10, 2022. We included 12 randomized controlled trials (RCTs) and performed a meta-analysis comparing the efficiency in the hearing recovery of intratympanic versus systemic steroid treatment, systemic versus combined, and intratympanic versus combined steroid treatment. The results of the intratympanic versus systemic steroid therapy comparison showed no actual difference in efficiency and no statistical significance (odds ratio: 1.07 (Mantel-Haenszel (M-H), fixed, 95% confidence interval (CI): 0.76-1.51)). Systemic steroid treatment was inferior to combined steroid treatment and was the only outcome with statistical significance (odds ratio: 0.55 (M-H, fixed, 95% CI: 0.38-0.80)). Intratympanic steroid treatment was inferior to combined steroid treatment, although the results were not statistically significant (odds ratio: 0.65 (M-H, fixed, 95% CI: 0.37-1.16)). In conclusion, systemic steroid therapy was inferior to combined steroid therapy. The comparison of intratympanic with systemic therapy and intratympanic with combined therapy showed no statistical significance. Further research is needed with more RCTs, and side effects should be considered.

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.

Clinical Analysis of Intratympanic Injection of Dexamethasone for Treating Sudden Deafness

Introduction

A variety of causes may induce sudden deafness. However, it remains challenging to determine the exact cause in a clinic. There is no standard treatment for this disease due to its unclear etiology.

Objective

The present study aims to investigate the clinical efficacy of the intratympanic injection of dexamethasone for treating sudden deafness.

Methods

A total of 154 patients with sudden deafness were retrospectively analyzed. The evaluation of sudden deafness was based on the AAO-HNS efficacy evaluative criteria. All patients were initially treated within seven days by an intravenous drip of methylprednisolone, vasodilator, and neurotrophic agents. These patients were divided into two groups: the treatment group (91 patients) and the control group (63 patients). Patients in the treatment group were given an intratympanic injection of dexamethasone, while patients in the control group were given conventional vasodilators and neurotrophic treatment.

Results

The effective rate in the treatment group was 47.25% (43/91 patients), and this was significantly higher than in the control group (14.29%, 9/63 patients). The adverse reactions in the treatment group included transient pain (7.69%, 7/91), but there was no vertigo in either group. There was one case of tympanic membrane perforation.

Conclusion

The intratympanic injection of dexamethasone is a better choice for refractory sudden deafness due to its high efficacy and fewer adverse reactions.

Tympanic Membrane Perforation After Intratympanic Steroid Injection: A Systematic Review and Meta-analysis

OBJECTIVE

We investigated the incidence of tympanic membrane (TM) perforations induced after intratympanic steroid injection (ITSI) in patients with sudden sensorineural hearing loss (SSNHL) through a systematic review and meta-analysis.

DATA SOURCES

PubMed, Embase, and MEDLINE.

REVIEW METHODS

Primary database searches were performed, and 1901 records were identified. After removal of 1802 articles through abstract screening, the remaining 99 full-text journals were assessed for eligibility to be included in the study. Fifty-eight studies that used either ventilation tubing (VT) or tympanocentesis (TC) for ITSI were selected for analysis. The subjects were divided into VT and TC groups. The rate of TM perforation after ITSI in 2 groups, sites of ITSI, needle gauge, and influence on residual hearing were investigated.

RESULTS

The cohorts comprised patients who underwent VT (n = 257, 9.6%) and TC (n = 2415, 90.4%). The proportion of TM perforation after ITSI in each group was 0.073 (95% CI, 0.0469-0.1113) and 0.010 (95% CI, 0.0045-0.0215), respectively, which suggested that the VT group showed a significantly higher TM perforation rate than the TC group (P < .001). In the subgroup analyses, there was no significant difference in the odds ratio for the rate of TM perforation according to the injection site and needle gauge for TC. The proportion of surgical repair showed no significant difference between the 2 groups.

CONCLUSION

ITSI via VT may have a significantly higher risk of TM perforation than ITSI via TC, although those are relatively small overall. ITSI should be performed in the direction to minimize possible adverse effects.

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.

Intratympanic steroid injection versus hyperbaric oxygen therapy in refractory sudden sensorineural hearing loss: a meta-analysis

OBJECTIVE

The present meta-analysis aims to compare the efficacy of intratympanic steroid (ITS) injection and hyperbaric oxygen (HBO) therapy as salvage treatments for refractory sudden sensorineural hearing loss (SSNHL).

DATA SOURCES

Comprehensive searches were performed in PubMed, EMBASE and the Cochrane Library from the date of the database inception to June 2020. All studies reporting the use of salvage ITS and HBO treatments in refractory SSNHL patients were included. Subsequently, the full texts of the eligible studies were evaluated.

METHODS

The quality and bias of the studies were assessed using the Newcastle-Ottawa Scale and Cochrane's risk of bias tools for nonrandomized and randomized studies, respectively. The data were analyzed using Comprehensive Meta-Analysis software (Version 3; Biostat, Englewood, NJ).

RESULTS

Three hundred and fourteen subjects in 3 observational studies and 1 randomized controlled trial met our inclusion criteria. The pooled results demonstrated that there were no significant differences in the mean posttreatment hearing gain between the ITS and HBO groups. The changes in word discrimination and hearing gain at 250, 500, 1000, 2000, 4000 and 8000 Hz were also comparable between the two salvage treatment groups.

CONCLUSIONS

The pooled results demonstrated that there were no significant differences in hearing improvements between salvage ITS injection and salvage HBO therapy after failed primary systemic steroid treatment in patients with SSNHL. However, spontaneous recovery could bias the treatment outcomes, and these results should be interpreted with caution. Clinicians may choose these salvage treatments according to personal experience and treatment availability. In cases in which specialized HBO facilities are difficult to access, salvage ITS injection can be provided with comparable responses.

[Hormonal influence on hearing]

BACKGROUND

Hearing loss leads to impairments in communication, social interactions, and cognitive functions. This renders early treatment particularly important. A causal therapy is not yet available. Human and animal studies have shown that certain hormones can have a positive effect on hearing.

OBJECTIVE

This review provides an overview of the effects of various hormones on hearing and describes the potential benefit for future therapeutic approaches.

MATERIALS AND METHODS

A systematic literature review of reviews dealing with the effects of various hormones on hearing in humans and animals published in PubMed between 2015 and 2020 was conducted.

RESULTS

Hormones may mediate antiapoptotic effects on structure-relevant cells of the cochlea and auditory pathway, and may influence hair cell functionality or the electrolyte balance of the endo- and perilymph. Current research focuses on glucocorticoids; the mineral corticoid aldosterone; the sex hormones estrogen, progesterone, and testosterone; the growth hormones GH (growth hormone) and IGF‑1 (insulin-like growth factor 1); thyroid hormones; and insulin. Study results are still inconsistent at this time, but various hormones appear to represent a possible future treatment option for acute hearing loss. Long-term hormone treatment, which would be necessary particularly in the case of age-related hearing loss, does not currently represent a sensible course of action due to the side effect profile of the systemic treatment/lack of practicable topical application options.

CONCLUSION

The mode of action of hormones is complex. Whether they can be used in the future for individualized treatment of patients with acute hearing impairment requires further investigation.

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.

Idiopathic sudden sensorineural hearing loss: Effectiveness of salvage treatment with low-dose intratympanic dexamethasone

Objectives

To evaluate hearing outcome of salvage treatment with intratympanic steroids (ITS) in idiopathic sudden sensorineural hearing loss (ISSNHL) refractory to initial systemic steroid (SS) therapy.

Material and methods

A retrospective medical chart review was conducted on 54 consecutive patients with ISSNHL refractory to SS. Salvage treatment with a low dose intratympanic dexamethasone (4 mg/ml) was offered after one week of primary treatment. Patients were divided into two groups: 25 patients accepted ITS (treatment group) and 29 patients did not undergo additional treatment (control group). A pure tone average (PTA) gain of at least 10 dB was considered hearing improvement.

Results

Hearing improvement rate was higher in ITS group compared to control group (40% vs. 13.8%, p = 0.035). A mean PTA improvement of 8.6 ± 9.8 dB was observed in the ITS group and, whereas the control group had an average hearing gain of 0.7 ± 2 dB (p < 0.001). Audiometric analysis revealed a significant hearing gain in ITS group at all tested frequencies compared to control group (p < 0.05). Analysis of the selected variables, identified intratympanic steroid treatment as the only independent prognostic factor for hearing improvement (OR = 4.2, 95% CI: 1.1-15.7; p = 0.04).

Conclusion

Intratympanic low dose dexamethasone is effective in patients with incomplete hearing recovery after primary systemic steroid treatment.

Intratympanic dexamethasone injection for sudden sensorineural hearing loss in pregnancy

BACKGROUND

As sudden sensorineural hearing loss (SSNHL) rarely occurs in pregnant women, there is a lack of knowledge and relevant research on its management.

AIM

To investigate the effect of intratympanic dexamethasone injection in the treatment of pregnant patients with SSNHL.

METHODS

A retrospective chart review was made for the period between June 2017 and August 2019 at our Department of Otorhinolaryngology-Head and Neck Surgery. Pregnant women who met the criteria for SSNHL were included and grouped based on the therapeutic modalities. The treatment group received intratympanic dexamethasone (2.5 mg) q.o.d. for a total of four times, while the control group received no medication other than bed rest and medical observations. All the patients were under close care of obstetricians. Pure-tone audiograms were performed before and after treatment.

RESULTS

Eleven patients who met the inclusion criteria were assigned to the treatment group (n = 7) and the control group (n = 4). The mean age of patients was 31.2 ± 3.8 years; the right ear was affected in seven (63.64%) cases. Two patients (18.2%) suffered from vertigo, 10 (90.9%) suffered from tinnitus and 6 (54.5%) suffered from aural fullness. The time from onset to clinic visit was relatively short, with a mean time of 1.3 ± 0.9 d. All the women were within the second or third trimester; the average gestation period was 26.0 ± 6.2 wk. The pure-tone averages at onset between the two groups were similar. After one wk of therapy, the treatment group had a curative rate of 57.1% and a significantly better hearing threshold and greater improvement compared to the control group (all P < 0.05). Some patients experienced transient discomfort from intratympanic injections that disappeared after getting rest, while none had permanent complications. All patients delivered healthy full-term neonates with an average Apgar score of 9.7 ± 0.5.

CONCLUSION

Intratympanic dexamethasone injections can be used as a first-line therapy in pregnant women with SSNHL.

Potential benefits of salvage intratympanic dexamethasone injection in profound idiopathic sudden sensorineural hearing loss

PURPOSES

To compare hearing recovery levels after initial treatment or salvage intratympanic dexamethasone injection (ITDI), and to find the prognostic factor on salvage ITDI therapy in profound ISSNHL.

METHODS

We retrospectively reviewed 115 patients with profound ISSNHL. All patients were treated with combination or systemic steroid therapy as the initial treatment. Next, we used salvage ITDI therapy on patients who showed slight or no improvement according to Siegel's criteria. To find the prognostic factors for the effectiveness of salvage ITDI therapy, we analyzed clinical data, such as, age, sex, vertigo, symptom duration, diabetes, hypertension, initial PTA, pre-salvage PTA, and treatment methods, using multiple regression analyses.

RESULTS

The rate of serviceable hearing recovery were 10.4% (12/115) in the initial-treatment group and 20.4% (21/103) in the salvage group. The difference was statistically significant (p = 0.041). Pre-salvage PTA, diabetes mellitus, and symptom duration were affective factors for the effectiveness of salvage ITDI therapy in profound ISSNHL refractory to initial treatment, with odds ratios of 1.169 (95% confidence interval, 1.088-1.256), 0.069 (95% confidence interval, 0.005-0.889), and 9.242 (95% confidence interval, 1.079-79.146).

CONCLUSIONS

Salvage therapy should be considered for profound ISSNHL, which is expected to result in poor prognosis or hearing recovery: ITSI therapy might be an effective treatment as salvage therapy.

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.

Comparison of 2 Different Intratympanic Methylprednisolone Injection Schedules in Combination With Intravenous Dexamethasone for Unilateral Sudden Sensorineural Hearing Loss

Sudden sensorineural hearing loss is a common otologic disease in clinic. Systemic and intratympanic steroid treatment have been proved to be effective, but the regimens vary from center to center. The purpose of the study is to analyze the effects of the combined application of intravenous dexamethasone and intratympanic methylprednisolone injection in different time strategies for the treatment of unilateral sudden sensorineural hearing loss. A retrospective chart review was performed for the period from March 2016 to June 2018 at our Department of Otorhinolaryngology-Head and Neck Surgery. A total number of 61 patients who met the academy criteria for unilateral sudden hearing loss were included and grouped based on the time to introduce intratympanic methylprednisolone. All the patients received intravenous dexamethasone 10 mg once daily for 5 days, followed 5 mg once daily for the next 7 days. Intratympanic methylprednisolone (40 mg) was injected every other day 4 times into all patients. This regimen was commenced on day 1 in group 1 and on day 6 in group 2. The pre and posttreatment pure-tone audiograms were analyzed. Sixty-one patients met our inclusion criteria. No significant differences were observed between patients' demographics or pretreatment hearing thresholds. In the 3 months posttreatment pure-tone audiogram assessment, the mean hearing threshold improvement were similar between groups with no frequency specificity. The curative rate in both groups were similar and satisfying. Two patients with diabetes mellitus had persistent small perforations. Some patients had other transient discomfort that disappeared before discharge. The different timing of initiation of intratympanic methylprednisolone injection does not significantly affect the outcome of the treatment for sudden sensorineural hearing loss. Thus, we suggest that intratympanic steroid injection should not be applied as a first-line method except for patients who do not respond early to systemic steroid therapy.

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.

Metachronous Sudden Sensorineural Hearing Loss: Patient Characteristics and Treatment Outcomes

OBJECTIVES

Idiopathic sudden sensorineural hearing loss (ISSNHL) is a distressing condition that can significantly affect quality of life. Unilateral ISSNHL, occurring first in 1 ear and then the contralateral ear at a separate and discrete time, is a rare presentation that we refer to as metachronous ISSNHL. Our objective was to characterize the presentation of metachronous ISSNHL and report on management and hearing outcomes.

STUDY DESIGN

Retrospective case series.

SETTING

Otology clinic at an academic tertiary referral center.

SUBJECTS AND METHODS

Patients ≥18 years old presenting with metachronous ISSNHL between April 2008 to November 2017 were identified through review of the clinic electronic medical record. Metachronous ISSNHL was defined as unilateral ISSNHL occurring in temporally discrete episodes (>6 months apart) affecting both ears. Patients with identifiable causes for sudden hearing loss were excluded. Patient demographics, comorbidities, management, and audiologic outcomes were recorded.

RESULTS

Eleven patients with metachronous ISSNHL were identified out of 558 patients with ISSNHL. In patients with metachronous ISSNHL, the mean ± standard deviation age at the time of ISSNHL in the second ear was 58.6 ± 15.2 years (range, 31-77 years). The mean interval between episodes was 9.6 ± 7.5 years (range, 1-22 years). Patients were treated with systemic and intratympanic steroids with variable hearing recovery; 5 patients with resultant bilateral severe to profound hearing loss underwent successful cochlear implantation.

CONCLUSION

Metachronous ISSNHL is uncommon. Treatment is similar to ISSNHL, and cochlear implantation can successfully restore hearing in individuals who do not experience recovery.

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.

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.

Overview of Federated Facility to Harmonize, Analyze and Management of Missing Data in Cohorts

Cohorts are instrumental for epidemiologically oriented observational studies. Cohort studies usually observe large groups of individuals for a specific period of time to identify the contributing factors to a specific outcome (for instance an illness) and create associations between risk factors and the outcome under study. In collaborative projects, federated data facilities are meta-database systems that are distributed across multiple locations that permit to analyze, combine, or harmonize data from different sources making them suitable for mega- and meta-analyses. The harmonization of data can increase the statistical power of studies through maximization of sample size, allowing for additional refined statistical analyses, which ultimately lead to answer research questions that could not be addressed while using a single study. Indeed, harmonized data can be analyzed through mega-analysis of raw data or fixed effects meta-analysis. Other types of data might be analyzed by e.g., random-effects meta-analyses or Bayesian evidence synthesis. In this article, we describe some methodological aspects related to the construction of a federated facility to optimize analyses of multiple datasets, the impact of missing data, and some methods for handling missing data in cohort studies.

Efficacy of 2 Different Intratympanic Steroid Regimen on Prevention of Cisplatin Ototoxicity: An Experimental Study

Ototoxicity is the general name of cochlear and vestibular organ injury resulting from encountering various therapeutic agents and chemical substances. Cisplatin is commonly used in the treatment of many cancers. In this study, the efficacy of intratympanic steroids was compared for preventing cisplatin ototoxicity. In this study, 32 (64 ears) rats were used by separating into 4 groups. Cisplatin was administered intraperitoneally to the first group (n = 8). Methylprednisolone and then cisplatin were administered intratympanically to the second group (n = 8). On the third group (n = 8), dexamethasone and then cisplatin were administered intratympanically. To the fourth group (n = 8), 0.9% NaCl and then cisplatin were given intratympanically. Otoacoustic emission (OAE) measurements and auditory brainstem responses (ABRs) tests were performed on all groups before and 72 hours after the procedure. Pretreatment of ABR-IV values were 4.29 ± 0.19 milliseconds in group 2 and 4.27 ± 0.16 milliseconds in group 3, whereas posttreatment ABR-IV values were 4.95 ± 0.35 milliseconds in group 2 and 4.65 ± 0.26 milliseconds in group 3. The ABR-IV values were measured significantly shorter in the rats given dexamethasone and methylprednisolone, according to control and cisplatin groups (P < .001). Pretreatment of ABR I-IV interval values were 2.98 ± 0.34 milliseconds and 3.03 ± 0.42 milliseconds in group 1 and group 4, respectively, and ABR I-IV interval values in group 1 and group 4 posttreatment were 3.49 ± 0.39 milliseconds and 3.5 ± 0.39 milliseconds in group 1 and group 4, respectively. Auditory brainstem responses I-IV interval was significantly longer in the cisplatin and control group than in the rats given dexamethasone and methylprednisolone (P < .001). After cisplatin treatment, OAE amplitudes decreased significantly in group 1 and group 4 for all frequencies, while OAE values were protected in methylprednisolone and dexamethasone group (P < .001). In conclusion, it has been shown that both agents have protective effects on cisplatin ototoxicity, with dexamethasone slightly more than methylprednisolone.

Intratympanic Methylprednisolone versus Dexamethasone for the Primary Treatment of Idiopathic Sudden Sensorineural Hearing Loss

OBJECTIVES

The aim of the present study was to compare the therapeutic effectiveness of intratympanic (IT) methylprednisolone and dexamethasone in the initial treatment of patients with idiopathic sudden sensorineural hearing loss (ISSHL).

MATERIALS AND METHODS

A total of 46 patients with ISSHL who had been treated with IT methylprednisolone or dexamethasone were included in the present study. Dexamethasone (4 mg/mL) and methylprednisolone (20 mg/mL) were given transtympanically to 22 and 24 patients, respectively, one dosage per day for 5 consecutive days. Audiologic evaluations were performed pretreatment, daily in inpatient clinics, and in the first week and second month after discharge, using four-frequency pure-tone average (PTA) and speech discrimination score (SDS). Audiologic improvement was classified according to the Furuhashi criteria.

RESULTS

According to the Furuhashi criteria, the therapeutic success rate was 62.5% (complete improvement 16.7% and marked improvement 45.8%) in the methylprednisolone group, whereas it was 54.6% (complete improvement 27.3% and marked improvement 27.3%) in the dexamethasone group. Therapeutic success was higher in the methylprednisolone group; however, it was not statistically significant. When the audiologic improvement was accepted as >10 dB in PTA, the therapeutic success rates were 83.3% in the methylprednisolone group and 72.8% in the dexamethasone group. The mean (±SD) improvement of PTA before and after treatment was 30.8±21.4 in the methylprednisolone group and 24.7±2.5 in the dexamethasone group. The mean improvement in SDS was 32.6±25 in the methylprednisolone group and 23.7±26.9 in the dexamethasone group.

CONCLUSION

IT steroids are safe, effective, and well-tolerated agents in the initial treatment of patients with ISSHL. Despite having different pharmacokinetic characteristics, IT methylprednisolone and dexamethasone have no superiorities over each other in the primary treatment in patients with ISSHL.

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.

Middle-ear dexamethasone delivery via ultrasound microbubbles attenuates noise-induced hearing loss

OBJECTIVES/HYPOTHESIS

In this study, we expanded our previous investigation by testing the efficiency of trans-round window membrane dexamethasone (DEX) delivery mediated by ultrasound (US)-aided microbubbles (MBs) and its preventive effects regarding noise exposure in animal models.

STUDY DESIGN

Live animal model.

METHODS

Forty-two pigmented male guinea pigs were divided into the following three groups: an US-MBs (USM) group, in which the tympanic bulla was filled with DEX and MBs and exposed to US; a round window soaking (RWS) group, without the US irradiation; and a control group. The above-mentioned manipulations were performed 2 hours prior to white noise exposure. The cochlear damage, including auditory threshold shifts, hair cell loss, and expression of cochlear HMGB1, was evaluated.

RESULTS

The enhanced DEX delivery efficiency of the USM group was approximately 2.4× to 11.2× greater than that of the RWS group. After the noise exposure, the RWS group showed significant cochlear protection compared with the control group, and more significant and dominant protective effects were demonstrated in the USM group.

CONCLUSIONS

The application of US-MBs provides a safe and more effective approach than spontaneous diffusion, which is commonly used in clinical practice; thus, this technique holds potential for future inner-ear drug delivery.

LEVEL OF EVIDENCE

NA Laryngoscope, 129:1907-1914, 2019.

Acquired sensorineural hearing loss in children: current research and therapeutic perspectives

The knowledge of mechanisms responsible for acquired sensorineural hearing loss in children, such as viral and bacterial infections, noise exposure, aminoglycoside and cisplatin ototoxicity, is increasing and progressively changing the clinical management of affected patients. Viral infections are by far the most relevant cause of acquired hearing loss, followed by aminoglycoside and platinum derivative ototoxicity; moreover, cochlear damage induced by noise overexposure, mainly in adolescents, is an emerging topic. Pharmacological approaches are still challenging to develop a truly effective cochlear protection; however, the use of steroids, antioxidants, antiviral drugs and other small molecules is encouraging for clinical practice. Most of evidence on the effectiveness of antioxidants is still limited to experimental models, while the use of corticosteroids and antiviral drugs has a wide correspondence in literature but with controversial safety. Future therapeutic perspectives include innovative strategies to transport drugs into the cochlea, such as molecules incorporated in nanoparticles that can be delivered to a specific target. Innovative approaches also include the gene therapy designed to compensate for abnormal genes or to make proteins by introducing genetic material into cells; finally, regenerative medicine (including stem cell approaches) may play a central role in the upcoming years in hearing preservation and restoration even if its role in the inner ear is still debated.

Comparison of intratympanic dexamethasone therapy and hyperbaric oxygen therapy for the salvage treatment of refractory high-frequency sudden sensorineural hearing loss

OBJECTIVE

This study aimed to compare the efficacy of intratympanic dexamethasone (ITD) therapy and hyperbaric oxygen(HBO) therapy for the salvage treatment of patients with high-frequency sudden sensorineural hearing loss (SSNHL) after the failure of conventional therapy.

MATERIALS AND METHODS

104 refractory high-frequency SSNHL patients were enrolled in our study. Among them, 31 received ITD alone (ITD group), 32 received HBO alone (HBO group) and 41 received no salvage therapies (control group). Hearing outcomes were determined by pure-tone average measured by audiometry. The total effective rates in the hearing recovery and improvement of tinnitus were calculated before and after salvage treatment.

RESULTS

There was no significant difference of the total effective rates in the hearing recovery between ITD and HBO group (p = 0.368). However, ITD therapy showed much better improvements of tinnitus than HBO therapy (p = 0.039). After ITD and HBO therapy, there were no significant differences in hearing gains at 2 and 4 KHz between ITD and HBO group (p = 0.468 and 0.934, respectively). Nevertheless, ITD therapy showed significant improvements of hearing gains at 8 KHz (p = 0.049) compared to that of HBO therapy.

CONCLUSION

ITD therapy may have better improvements of tinnitus and hearing gains at 8 KHz than HBO therapy in patients with refractory high-frequency SSNHL.

Update on consensus on diagnosis and treatment of idiopathic sudden sensorineural hearing loss

INTRODUCTION

Idiopathic sudden sensorineural hearing loss (ISSNHL) is a sudden, unexplained unilateral hearing loss.

OBJECTIVES

To update the Spanish Consensus on the diagnosis, treatment and follow-up of ISSNHL.

MATERIAL AND METHODS

After a systematic review of the literature from 1966 to March 2018, on MESH terms «(acute or sudden) hearing loss or deafness», a third update was performed, including 1508 relevant papers.

RESULTS

Regarding diagnosis, 11ISSNHL is clinically suspected, the following diagnostic tests are mandatory: otoscopy, acumetry, tonal audiometry, speech audiometry, and tympanometry, to discount conductive causes. After clinical diagnosis has been established, and before treatment is started, a full analysis should be performed. An MRI should then be requested, ideally performed during the first 15 days after diagnosis, to discount specific causes and to help to understand the physiopathological mechanisms in each case. Although treatment is very controversial, due to its effect on quality of life after ISSNHL and the few rare adverse effects associated with short-term steroid treatment, this consensus recommends that all patients should be treated with steroids, orally and/or intratympanically, depending on each patient. In the event of failure of systemic steroids, intratympanic rescue is also recommended. Follow-up should be at day 7, and after 12 months.

CONCLUSION

By consensus, results after treatment should be reported as absolute decibels recovered in pure tonal audiometry and as improvement in speech audiometry.

Intratympanic steroid use for idiopathic sudden sensorineural hearing loss: current otolaryngology practice in Germany and Austria

AIMS

The frequency of the use of intratympanic steroids (ITS) as a treatment for idiopathic sudden sensorineural hearing loss (ISSNHL) in Europe is still unknown and remains a contentious issue amongst otolaryngologists. We undertook a survey of otolaryngologists in Germany and Austria to establish if there is any professional consensus with which to form a protocol for its use.

METHODS

A survey of 21 questions was distributed electronically to otolaryngologists in Germany and Austria and data on demographics, indications for intratympanic treatment, procedure, follow-up, and outcomes were analysed.

RESULTS

We received 908 responses. 49.1% of otolaryngologists used ITS for ISSNHL. Of those otolaryngologists who use ITS, 73.7% do not use it as primary treatment. 20.6% use ITS in conjunction with oral steroids for primary treatment and only 5.8% use ITS as monotherapy for primary treatment. 90.5% use ITS as salvage therapy. 81.1% do not consider the use of ITS after 2 weeks from the onset of symptoms. 8.3% used a tympanostomy tube and while the most commonly used steroid was dexamethasone at a concentration of 4 mg/ml (61%), a wide variety or other steroids and concentrations were used.

CONCLUSIONS

This survey illustrates wide variation of current practice of intratympanic corticosteroid injection for ISSHL in Germany and Austria. In the absence of high-level evidence, knowing what current practice is allows clinicians to assess what they do against what their colleagues are doing, and if they do something very different, make them question their practice. Moreover, the obtained data will help to direct future clinical trials with the aim to compare the outcomes of more commonly used protocols.

Diagnostics and therapy of sudden hearing loss

This article reviews recent aspects of diagnostics, differential diagnostics, and evidence in systemic and local therapy of idiopathic sudden sensorineural hearing loss (ISSHL). Since a number of disorders can be accompanied by sudden hearing loss, a meaningful and targeted diagnostic strategy is of utmost importance. An important differential diagnosis of sudden hearing loss are intralabyrinthine schwannomas (ILS). The incidence of ILS is probably significantly underestimated. This may be due to the lack of awareness or lack of explicit search for an intralabyrinthine tumor on MRI or an inappropriate MRI technique for the evaluation of sudden hearing loss ("head MRI" instead of "temporal bone MRI" with too high slice thicknesses). Therefore, the request to the radiologist should specifically include the question for (or exclusion of) an ILS. With special MRI techniques, it is possibly today to visualize an endolymphatic hydrops. The evidence in the therapy of ISSHL is - with respect to the quality and not quantity of studies - unsatisfying. The value of systemically (low dose) or intratympanically applied corticosteroids in the primary treatment of ISSHL is still unclear. In order to investigate the efficacy and safety of high dose corticosteroids as primary therapy for ISSHL, a national, multicenter, three-armed, randomized, triple-blind controlled clinical trial is currently performed in Germany (http://hodokort-studie.hno.org/). After insufficient recovery of the threshold with systemic therapy of ISSHL, intratympanic corticosteroid therapy appears to be associated with a significantly higher chance of an improved hearing threshold than no therapy or placebo. Both, hearing gain and final hearing threshold, however, appear to be independent from the onset of secondary therapy. Based on currently available data from clinical studies, no recommendation can be made with respect to the type of corticosteroid and specifics of the intratympanic application protocol.

Current concepts in the management of idiopathic sudden sensorineural hearing loss

PURPOSE OF REVIEW

The purpose of this manuscript is to review the initial management strategies for idiopathic sudden sensorineural hearing loss, with an emphasis on the role that steroids play in treatment of this condition, and discuss options for auditory rehabilitation of persistent unilateral hearing loss.

RECENT FINDINGS

Recent data suggest that hearing improvement may be greater for patients initially treated with both systemic and intratympanic steroid when compared with those treated with systemic steroids alone. Salvage intratympanic steroids have been shown to confer hearing benefit if initial management fails. The ideal dosing regimen for intratympanic steroids has not been established, but evidence supports that higher dosing strategies are advantageous. Cochlear implantation has emerged as a strategy for auditory rehabilitation of persistent unilateral hearing loss. Recent studies have demonstrated high patient satisfaction, subjective improvement in tinnitus, and objective performance benefit after cochlear implantation for single-sided deafness.

SUMMARY

Patients can be offered steroid therapy in the initial management of idiopathic sudden sensorineural hearing loss, but should be counseled that the efficacy of steroids remains unclear. If patients fail to improve with initial management, salvage intratympanic steroid administration should be considered. If hearing loss persists long term, options for auditory rehabilitation should be discussed.

Intratympanic glucocorticosteroid therapy for idiopathic sudden hearing loss: Meta-analysis of randomized controlled trials

BACKGROUND AND OBJECTIVE

Glucocorticoids are the standard treatment for idiopathic sudden sensorineural hearing loss (ISSNHL), but whether intratympanic or systemic therapy is superior remains controversial. Previous meta-analyses of this question have omitted key clinical trials or included observational studies.

METHODS

English-language randomized controlled trials in OvidSP, PubMed, Embase, CINAHL, and the Cochrane Library comparing intratympanic versus systemic glucocorticoid therapy for ISSNHL were meta-analyzed using RevMan 5.3. The primary outcome of interest was improvement in pure tone average (PTA) threshold.

RESULTS

Six trials involving 248 patients receiving intratympanic steroids and 236 receiving systemic steroids were meta-analyzed. PTA thresholds were similar between the 2 groups at 3 months after therapy initiation (mean difference, 0.24; 95% confidence interval [CI] -2.43 to 2.91, P = .86; I = 54%, P = .07, random-effects model). PTA thresholds were also similar at 6 months (mean difference, 4.69, 95% CI -5.84 to 15.22, P = .38), although the results showed extremely high heterogeneity (I = 98%). Sensitivity analysis indicated that a single trial containing 250 patients provided the strongest evidence for equivalence between the 2 types of therapy. Rates of recovery within 3 months (defined as PTA improvement >10 dB) were similar between the 2 types of therapy (odds ratio 0.92, 95% CI 0.59-1.43, P = .70), with no significant heterogeneity in the pooled data (I = 1%, P = .40).

CONCLUSION

Intratympanic and systemic steroids' therapies appear to show similar short-term efficacy for restoring hearing in patients with ISSNHL. Intratympanic therapy may reduce systemic side effects associated with steroid use.

Systemic, intratympanic and combined administration of steroids for sudden hearing loss. A prospective randomized multicenter trial

PURPOSE

The purpose of this prospective, randomized, multicenter clinical trial was to compare the therapeutic efficacy of systemic versus intratympanic versus combined administration of steroids in the treatment of idiopathic sudden sensorineural hearing loss.

METHODS

102 patients with an up to 14 days history of idiopathic sudden sensorineural hearing loss were randomized to 1 of 3 arms and followed prospectively. Group A (35 patients) received prednisolone intravenously followed by methylprednisolone orally, whereas Group B (34 patients) were administered intratympanic methylprednisolone. Patients in Group C (33 patients) were administered the combination of the above-mentioned treatment modalities. The patients were followed-up with pure tone audiograms on days 1 (initiation of treatment), 3, 5, 10, 30 and 90.

RESULTS

The final mean hearing gain was 29.0 dB HL for Group A, 27.0 dB HL for Group B and 29.8 dB HL for Group C. The differences between the three groups were not statistically significant. When hearing improvement was assessed according to Siegel's criteria, no statistically significant difference was recorded either. Furthermore, patients younger than 60 years old achieved significantly better hearing outcomes.

CONCLUSIONS

The results demonstrated that systemic, intratympanic and combined steroid administration have similar results in the primary treatment of idiopathic sudden hearing loss. Younger patients are more likely to achieve better hearing outcomes.

Intratympanic steroid injection and hyperbaric oxygen therapy for the treatment of refractory sudden hearing loss

INTRODUCTION

Controversy surrounds the use of salvage therapies to treat sudden sensorineural hearing loss (SSNHL), with no consensus on recommendations. While several studies have demonstrated the effectiveness of intratympanic administration of steroids (ITS) and hyperbaric oxygen (HBO) treatment, few have compared the efficacy of ITS and HBO therapy in patients with refractory SSNHL.

OBJECTIVE

We evaluated the efficiency of ITS and HBO therapy in patients with refractory SSNHL.

METHODS

Patients who did not adequately benefit from systemic treatment were evaluated retrospectively. Refractory patients were defined as those who gained less than 20dB in hearing after initial treatment. All refractory patients were informed about salvage therapy options: ITS or HBO therapy, the advantages and disadvantages of which were explained briefly. ITS involved 4mg/mL dexamethasone administered through a 25 gauge needle. Patients underwent HBO therapy in a hyperbaric chamber where they breathed 100% oxygen for 120min at 2.5 atmospheric pressure. The hearing levels of both groups were evaluated before the salvage therapy and at 3 months after treatment. Improvements in hearing were evaluated according to the Furahashi criteria. We also compared the two therapies in terms of speech discrimination scores (SDSs) and the recovery of all frequencies.

RESULTS

The salvage therapies generated similar results. Changes in pure tone averages and SDSs were similar for ITS and HBO therapy (p=0.364 and p=0.113). Comparison of SDSs and hearing thresholds at all frequencies showed similar levels of improvement.

CONCLUSION

ITS and HBO therapy produced similar improvements in SSNHL patients, but the sample size was too small to draw definitive conclusions. Further randomized controlled studies are needed to identify the best therapy for patients with refractory sudden hearing loss.