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

[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).

Microbubble-assisted ultrasound for inner ear drug delivery

Treating pathologies of the inner ear is a major challenge. To date, a wide range of procedures exists for administering therapeutic agents to the inner ear, with varying degrees of success. The key is to deliver therapeutics in a way that is minimally invasive, effective, long-lasting, and without adverse effects on vestibular and cochlear function. Microbubble-assisted ultrasound ("sonoporation") is a promising new modality that can be adapted to the inner ear. Combining ultrasound technology with microbubbles in the middle ear can increase the permeability of the round window, enabling therapeutic agents to be delivered safely and effectively to the inner ear in a targeted manner. As such, sonoporation is a promising new approach to treat hearing loss and vertigo. This review summarizes all studies on the delivery of therapeutic molecules to the inner ear using sonoporation.

[Intratympanic Drug Application - Indication and Procedure]

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

Diagnosis, differential diagnosis, and treatment for sudden sensorineural hearing loss: Current otolaryngology practices in China

Introduction

Although sudden sensorineural hearing loss (SSNHL) has been attempted to be understood for 70 years, diagnosis and treatment strategies still have strong heterogeneity worldwide, which are reflected in the guidelines issued by countries and the clinical practice of otolaryngologists.

Methods

Questionnaires were sent to registered otolaryngologists nationwide via an online questionnaire system. We investigated the current views and clinical practices of otolaryngologists in mainland China about the diagnosis, examination, and treatment strategies of SSNHL.

Results

Most otolaryngologists supported diagnostic classification via audiograms. Regional economic situation and hospital grade affected application strategies for differential diagnosis. Regarding corticosteroid therapy, 54.9% of respondents opted to discontinue the drug 5 days after systemic administration. Both intratympanic therapy and post-auricular injections were selected by more than half of the respondents as initial and salvage treatments.

Discussion

Chinese otolaryngologists exhibit heterogeneity in clinical practices for SSNHL, including distinct approaches to combination therapy and local application of steroids. This study pointed out Chinese doctors' similarities, differences, and unique strategies in diagnosing and treating SSNHL and analyzed the possible reasons to help the world understand the current otolaryngology practices in China.

Intratympanic Substance Distribution After Injection of Liquid and Thermosensitive Drug Carriers: An Endoscopic Study

OBJECTIVE

In the treatment of inner ear conditions, intratympanic injection emerges as an important drug delivery method. Novel compounds designed for intratympanic injection are routinely loaded in viscous drug carriers. To date, it is unclear if they can freely distribute in the middle ear. The aims of this study were to investigate the middle ear distribution of different drug carriers during intratympanic injection and to determine an optimal injection method for thermosensitive hydrogels.

METHODS

Twenty-one human temporal bones were intratympanically injected with fluid drug carriers or poloxamer-407 hydrogels at different tympanic membrane injection sites (inferior, anterior-superior) using different needle types (Whitacre, Quincke). Fluid distribution was evaluated via an endoscopic view. Injection volume, duration, backflow, and overall safety were analyzed.

RESULTS

Liquid drug carriers distribute effortlessly in the middle ear, whereas an additional ventilation hole is advantageous when applying thermosensitive hydrogels. The round window is coated with required volumes between 150 and 200 μl, irrespective of the injection position. Required volumes to also coat the stapedial footplate ranged from 310 to 440 μl. Use of the Whitacre-type needle reduced backflow to the ear canal and enabled longer tympanic membrane visibility when no additional ventilation hole was placed.

CONCLUSION

Intratympanic injection is a safe and reliable method for the application of thermosensitive hydrogels. The round window niche is readily filled regardless of the injected formulation and injection position. Although fluid drug carriers distribute effortlessly in the middle ear, the placement of an additional ventilation hole might facilitate the application of viscous hydrogels.

Triamcinolone acetonide can be detected in cerebrospinal fluid after intratympanic injection

Intratympanically applied treatments are of increasing interest to the otologic community to treat sudden sensorineural hearing loss or vestibular disorders but also to deliver gene therapy agents, or biologics to the inner ear. Further diversion from the middle ear and perilymph to blood circulation and cerebrospinal fluid via the cochlear aqueduct are one of the limiting factors and so far not understood well enough. In this study, intratympanically applied triamcinolone acetonide was determined in cerebrospinal fluid. Additionally, perilymph was sampled through the round window membrane as well as at the lateral semicircular canal to determine drug levels. Of the twenty-one included patients, triamcinolone acetonide was quantifiable in cerebrospinal fluid in 43% at very low levels (range 0 ng/ml - 6.2 ng/ml) which did not correlate with perilymph levels. Drug levels at the two different perilymph sampling sites were within a range of 13.5 ng/ml to 1180.0 ng/ml. Results suggest an equal distribution of triamcinolone acetonide to semicircular canals, which might support the use of triamcinolone acetonide as a treatment option for vestibular pathologies such as Menièrés disease. On the other hand, the distribution to cerebrospinal fluid might be limiting current approaches in gene therapy where a central distribution is unwanted.

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.

Steroid Nomenclature in Inner Ear Therapy

: Local glucocorticosteroid ("steroid") therapy is widely used to treat the inner ears of patients with Menière's disease, idiopathic sudden sensorineural hearing loss and in combination with cochlear implants. Applied steroids have included dexamethasone, methylprednisolone, and triamcinolone. In reality, however, this is often not true and the steroid forms commonly applied are dexamethasone-phosphate, methylprednisolone-hemisuccinate, or triamcinolone-acetonide. In each case, the additional component is not a counter-ion but is covalently bound to the molecule to increase aqueous solubility or potency. These drug forms are approved for intravenous or intramuscular delivery and are used "off-label" in the ear. When given systemically, the molecular form of the drug is of minor importance as the drugs are rapidly metabolized. In contrast, when administered intratympanically, the exact form of the drug has a major influence on entry into perilymph and elimination from perilymph, which in turn influences distribution along the cochlear scalae. Dexamethasone-phosphate has completely different molecular properties to dexamethasone and has different pharmacokinetic properties entering and leaving perilymph. Molecular properties and perilymph pharmacokinetics also differ markedly for triamcinolone and triamcinolone-acetonide. Methylprednisolone-hemisuccinate has completely different molecular properties to methylprednisolone. In the ear, different steroid forms cannot therefore be regarded as equivalent in terms of pharmacokinetics or efficacy. This presents a terminology problem, where in many cases the drug stated in publications may not be the form actually administered. The lack of precision in nomenclature is a serious problem for the inner ear drug delivery field and needs to be recognized.

Clinical Feature and Prognosis of Sudden Sensorineural Hearing Loss With Rheumatoid Arthritis

OBJECTIVES

Recent publications reported that patients with rheumatoid arthritis (RA) experience an increased risk of suffering sudden sensorineural hearing loss (SSNHL), however, these cases are poorly understood. This study aims to explore the clinical presentations and hearing recovery of SSNHL patients with RA.

STUDY DESIGN

Retrospective study.

SETTING

Tertiary medical center.

PATIENTS

Forty-seven SSNHL patients with RA (RA group) and 431 SSNHL patients without RA (non-RA group) were recruited between April 2015 and June 2019.

INTERVENTIONS

In the non-RA group, all patients were administrated with oral steroids. In the RA group, 21 patients were treated with oral steroid (OS group) and 26 patients were administrated with intratympanic steroids plus oral steroids (IS+OS group).

MAIN OUTCOME MEASURES

We explored the clinical features and hearing recovery of SSNHL patients with RA in comparison with patients without RA, we also evaluated the therapeutic effect of combined steroids in SSNHL patients with RA.

RESULTS

RA group had higher initial hearing loss level (mean 68.5 dB), final hearing threshold (mean 52.3 dB), the rates of profound hearing loss (48.9%), and no recovery (48.9%) than non-RA group (mean 55.1 dB, mean 34.8 dB, 32.9 and 27.6%, all p < 0.05), however, had lower hearing gains (mean 16.1 dB) and the rate of partial recovery (12.8%) than non-RA group (mean 20.3 dB and 28.8%, all p < 0.05). Furthermore, IS+OS group had higher hearing gains (mean 21.1 dB) and lower rate of no recovery (30.8%) than in the OS group (mean 10.0 dB and 71.4%, all p < 0.05).

CONCLUSIONS

SSNHL patients with RA experienced severe hearing loss and had poor hearing prognosis. IS+OS provide better hearing recovery than OS for this population.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Steroid Administration Approach for Idiopathic Sudden Sensorineural Hearing Loss: A National Survey in China

OBJECTIVE

To optimize a protocol for the steroid administration approach for idiopathic sudden sensorineural hearing loss (ISSNHL) in China.

METHODS

A questionnaire was distributed to otolaryngologists. The data on demographics, indications for first-line and salvage treatment, such as intratympanic administration of steroids (ITS) and postauricular steroids (PAS), and procedures were analyzed.

RESULTS

74 respondents used oral steroids, 112 used intravenous injections, 10 used ITS and 6 used PAS as a monotherapy for first-line treatment, and 135 used ITS or PAS in conjunction with oral or intravenous injection as a first-line treatment. Of the 249 respondents who used ITS, 97.19% adopted it as salvage therapy. The most commonly used steroid was 0.5 ml dexamethasone at 5 mg/ml and the most common side effect was pain. Of the 174 respondents who used PAS, 94.25% used it as salvage therapy. The most commonly used steroid was 0.5 ml methylprednisolone mixed with 0.5 ml lidocaine.

CONCLUSIONS

The obtained data suggested that intravenous injection of steroids was the most popular treatment for ISSNHL and that ITS or PAS were used as a salvage treatment in China.

Intratympanic application of triamcinolone in sudden hearing loss-radiologic anatomy in cone beam CT and its' correlation to clinical outcome

PURPOSE

To evaluate temporal bone cone-beam CT in patients with idiopathic sudden sensorineural hearing loss (ISSNHL) being treated with primary and secondary intratympanic (IT) triamcinolone and to possibly correlate these results to the clinical outcome.

METHODS

Retrospective analysis of patients treated with IT triamcinolone for ISSNHL at our department in 2018. Pre- and post-therapeutic audiologic examinations included four-tone average (FTA) at 0.5, 1, 2 and 3 kHz. Using a clinical questionnaire, pre-therapeutic CBCT scans were re-evaluated looking at items, which might interfere with adequate drug diffusion into the inner ear (e.g. bony overhangs or secondary membranes at the round or oval window).

RESULTS

Thirty-one patients were included. Twenty-four (77%; group A) had experienced ineffective systemic steroid therapy before and seven (23%; group B) received primary IT injections. Four group A-patients (21%) and two group B-patients (33%) showed a post-therapeutic FTA improvement of more than 15 dB HL. Bony overhangs at the round window niche (RWN) were present in seven cases (26%), a secondary membrane at the RWN in four (15%) and soft tissue in eight (30%) cases, respectively.

CONCLUSION

Most patients present radiological findings in CBCT imaging, which might interfere with drug diffusion through the RW membrane. Interestingly, soft or bony tissue obstructing the RWN or the OWN was found in 50% of patients, who showed improvement of hearing. We conclude that radiologic 'tiny' findings are either clinically irrelevant or improvement in hearing is independent from intratympanic drug delivery.

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.

Prognostic factors regarding the hearing outcome in severe to profound sudden sensorineural hearing loss treated by tympanotomy and sealing of labyrinthine windows after ineffective systemic corticosteroid application

PURPOSE

Tympanotomy and sealing of labyrinthine membranes has become in some centers used to treat severe to profound sudden sensorineural hearing loss refractory to conservative treatment. The aim of this retrospective study was to determine which preoperative factors influence the likelihood of postoperative recovery according to different audiological assessment criteria.

METHODS

The mean final hearing threshold, the hearing improvement, the probability of a complete recovery according to two different classifications, and probability of a significant recovery of 136 adult subjects were studied by univariate and multivariate analyses.

RESULTS

The subject's mean postoperative 4-pure-tone-average was 63.9 ± 35.9 dB, the mean improvement was 42.8 ± 32.6 dB. Depending on the classification system used, 18.4-28.0% of subjects experienced a complete recovery. 77.2% of subjects had a significant hearing improvement. History of a pressure change (odds ratio (OR):4.6) was the only positive prognostic factor for hearing improvement. It also enhanced probability of experiencing a complete hearing recovery (OR: 2.8-6.3). Preoperative total deafness (OR: 1.5-1.9) and vertigo (OR: 3.3-4.6) were negative prognostic factors for the mean final hearing threshold and the probability of a complete hearing recovery. Patients with a preceding pressure change event achieved a complete recovery in 45.5-50.0%, those without such an event recovered completely only in 13.2-23.7%.

CONCLUSION

Evaluating prognostic factors and the rate of complete hearing recovery are influenced by the underlying assessment parameters. In addition to the mean postoperative hearing threshold and hearing gain, the probability of regaining a serviceable hearing is clinically important for the individual and should be added to the assessment criteria in future studies.