High Dose of Intratympanic Steroids for Sudden Sensorineural Hearing Loss Salvage

Hyaluronic acid-ibuprofen conjugation: a novel ototherapeutic approach protecting inner ear cells from inflammation-mediated damage

There is a substantial need of effective drugs for the treatment of hearing loss, which affects nearly 500 million individuals globally. Hearing loss can be the result of intense or prolonged noise exposure, ototoxic drugs, infections, and trauma, which trigger inflammatory signaling cascades that lead to irreversible damage to cochlear structures. To address this, we developed and characterized a series of covalent conjugates of anti-inflammatory drugs to hyaluronic acid (HA), for potential use as topical ototherapeutics. These conjugates were tested in in vitro assays designed to mirror physiological processes typically observed with acoustic trauma. Intense noise exposure leads to macrophage recruitment to the cochlea and subsequent inflammatory damage to sensory cells. We therefore first tested our conjugates' ability to reduce the release of inflammatory cytokines in macrophages. This anti-inflammatory effect on macrophages also translated to increased cochlear cell viability. In our initial screening, one conjugate, ibuprofen-HA, demonstrated significantly higher anti-inflammatory potential than its counterparts. Subsequent cytokine release profiling of ibuprofen-HA further confirmed its ability to reduce a wider range of inflammatory markers, to a greater extent than its equivalent unconjugated drug. The conjugate's potential as a topical therapeutic was then assessed in previously developed tympanic and round window membrane tissue permeation models. As expected, our data indicate that the conjugate has limited tympanic membrane model permeability; however, it readily permeated the round window membrane model and to a greater extent than the unconjugated drug. Interestingly, our data also revealed that ibuprofen-HA was well tolerated in cellular and tissue cytocompatibility assays, whereas the unconjugated drug displayed significant cytotoxicity at equivalent concentrations. Moreover, our data highlighted the importance of chemical conjugation of ibuprofen to HA; the conjugate had improved anti-inflammatory effects, significantly reduced cytotoxicity, and is more suitable for therapeutic formulation. Overall, this work suggests that ibuprofen-HA could be a promising safe and effective topical ototherapeutic for inflammation-mediated cochlear damage.

Modified intratympanic steroid therapy for sudden sensorineural hearing loss via tympanic tube and gelfoam as a salvage treatment

Background

Sudden sensorineural hearing loss (SSNHL) is a prevalent emergency in ear, nose, and throat practice. Previous studies have demonstrated that intratympanic steroid therapy (IST) can serve as a salvage treatment for SSNHL after the failure of systemic steroid therapy (SST).

Objective

This study aimed to analyze the efficacy of modified IST involving the insertion of a tympanic tube and gelfoam as a salvage treatment for patients with SSNHL, and to explore its associated factors.

Methods

Totally, 74 patients who were aged 22-81 years with SSNHL were enrolled and allocated to either the control group (n = 25) or the treatment group (n = 49) based on their treatment modalities. All patients received SST lasting for at least 7 days. Subsequently, patients in the treatment group, after SST failure, underwent IST twice a week for 2-6 weeks, while the control group did not. Efficacy was assessed by the improvement in pure tone average at the affected frequency at the beginning and end of IST.

Results

Hearing improvement in all patients after IST in the treatment group was 9.71 ± 14.84 dB, with significant improvement at affected frequencies (250-8000 Hz) compared with the control group (P < 0.05). The findings indicated the duration from the onset of SSNHL to the beginning of IST as an independent factor for pure tone average improvement after treatment (P = 0.002), whereas age, duration of SST, and time of IST were not (P > 0.05).

Conclusion

The modified IST was demonstrated to be a safe and effective method as a salvage treatment for SSNHL. This study explored the efficacy of a modified IST approach, incorporating the utilization of tympanic tubes and gelfoam as key components. The findings underscore the advantages of gelfoam as a strategic drug carrier placed in the round window niche. By minimizing drug loss, extending action time, and increasing perilymph concentration, gelfoam enhances the therapeutic impact of IST, contributing to improved hearing outcomes in patients with SSNHL.

Delivery of Dexamethasone to the Round Window Niche by Saturated Gelatin Sponge for Refractory Sudden Sensorineural Hearing Loss: A Preliminary Study

OBJECTIVE

The aim of this study was to evaluate the hearing outcome of dexamethasone sodium phosphate (DSP) delivery to the round window niche by saturated gelatin sponge for refractory sudden sensorineural hearing loss.

PATIENTS

Twenty patients with unilateral sudden sensorineural hearing loss with an improvement of pure-tone average (PTA) less than 10 dB after primary systemic treatment with steroids.

INTERVENTIONS

Delivery of DSP to the round window niche via saturated sponge gelatin for 2 weeks.

MAIN OUTCOME MEASURES

Pure-tone audiometry was taken at the beginning and 4 to 8 weeks after the end of the salvage treatment.

RESULTS

PTA thresholds were improved at least 10 dB in 11 of 20 patients (55%) by a mean value of 11.9 dB. The hearing threshold at 500, 1000, and 2000 Hz were improved after salvage treatment, but there was no significant change at 4000 Hz. The PTAs also recovered after the salvage treatment.

CONCLUSIONS

Delivery of DSP to the round window niche via saturated gelatin sponge is a simple and feasible way to treat refractory sudden sensorineural hearing loss with a risk of permanent tympanic membrane perforation.

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

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.

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.

Pharmacotherapy of Tinnitus

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