Diagnostics and therapy of sudden hearing loss

Current Role of the Nonsteroid Treatment of Idiopathic Sudden Sensorineural Hearing Loss (ISSNHL): A Narrative Review

Sudden sensorineural hearing loss (SSHNL) is an abruptly appearing hearing loss. The etiology remains unclear, although vascular pathologies, viral infections, or autoimmune disease contribute to the understanding of this pathology. Systematic steroids are often used as the first-line treatment because of their anti-inflammatory effect. However, there remains controversy about the use of steroids and other alternative treatments, as hyperbaric oxygen therapy (HBOT), exploratory tympanotomy, prostaglandin, N-acetylcysteine, or defibrinogenation therapy. In this study, we aim to review the various treatment options currently available for sudden hearing loss, with the objective of advancing our understanding of this condition and clarifying information to guide future clinical practice guidelines.

MRI-confirmed cochlear artery infarct clinically diagnosed in a patient with sickle cell disease: a case report

PURPOSE

To corroborate the vascular etiology of sudden sensorineural hearing loss (SNHL) utilizing magnetic resonance imaging (MRI).

PATIENT

A 24-year-old male with a history of sickle cell disease experienced sudden SNHL and right horizontal nystagmus, without accompanying vertigo.

INTERVENTION

Audiometric evaluation revealed left-sided SNHL, predominantly affecting high frequencies. Video head impulse testing demonstrated isolated dysfunction of the left posterior semicircular canal. An urgent brain MRI identified a recent punctiform ischemic stroke in the frontal region. A subsequent MRI, conducted with a 4-hour delay and post-contrast enhancement, highlighted a hyperintense signal within the left cochlear region and the left posterior semicircular canal.

CONCLUSION

The investigative results substantiate an infarction in the territory of the cochlear artery, precipitated by a vaso-occlusive event, thereby reinforcing the vascular hypothesis of cochleovestibular artery syndrome. This case underscores the congruence between clinical observations and delayed post-contrast MRI findings.

Probucol-bile acid nanoparticles: a novel approach and promising solution to prevent cellular oxidative stress in sensorineural hearing loss

The use of antioxidants could thus prove an effective medication to prevent or facilitate recovery from oxidative stress-induced sensorineural hearing loss (SNHL). One promising strategy to prevent SNHL is developing probucol (PB)-based nanoparticles using encapsulation technology and administering them to the inner ear via the established intratympanic route. The preclinical, clinical and epidemiological studies support that PB is a proven antioxidant that could effectively prevent oxidative stress in different study models. Such findings suggest its applicability in preventing oxidative stress within the inner ear and its associated neural cells. However, several hurdles, such as overcoming the blood-labyrinth barrier, ensuring sustained release, minimising systemic side effects and optimising targeted delivery in the intricate inner ear structures, must be overcome to efficiently deliver PB to the inner ear. This review explores the background and pathogenesis of hearing loss, the potential of PB in treating oxidative stress and its cellular mechanisms, and the obstacles linked to inner ear drug delivery for effectively introducing PB to the inner ear.

[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).

Safety and audiological outcome in a case series of tertiary therapy of sudden hearing loss with a biodegradable drug delivery implant for controlled release of dexamethasone to the inner ear

Background

Intratympanic injections of glucocorticoids have become increasingly common in the treatment of idiopathic sudden sensorineural hearing loss (ISSHL). However, due to their fast elimination, sustained applications have been suggested for local drug delivery to the inner ear.

Materials and methods

The study is based on a retrospective chart review of patients treated for ISSHL at a single tertiary (university) referral center. We included patients who were treated with a solid, biodegradable, poly(D,L-lactic-co-glycolic acid) (PLGA)-based drug delivery system providing sustained delivery of dexamethasone extracochlear into the round window niche (n = 15) or intracochlear into scala tympani (n = 2) for tertiary therapy of ISSHL in patients without serviceable hearing after primary systemic and secondary intratympanic glucocorticoid therapy. We evaluated the feasibility and safety through clinical evaluation, histological examination, and functional tests [pure-tone threshold (PTA), word recognition scores (WRS)].

Results

With adequate surgical preparation of the round window niche, implantation was feasible in all patients. Histologic examination of the material in the round window niche showed signs of resorption without relevant inflammation or foreign body reaction to the implant. In patients where the basal part of scala tympani was assessable during later cochlear implantation, no pathological findings were found. In the patients with extracochlear application, average preoperative PTA was 84.7 dB HL (SD: 20.0) and 76.7 dB HL (SD: 16.7) at follow-up (p = 0.08). The preoperative average maximum WRS was 14.6% (SD: 17.9) and 39.3% (SD: 30.7) at follow-up (p = 0.11). Six patients (40%), however, reached serviceable hearing. The two patients with intracochlear application did not improve.

Conclusion

The extracochlear application of the controlled release system in the round window niche and – based on limited observations - intracochlear implantation into scala tympani appears feasible and safe. Due to the uncontrolled study design, conclusions about the efficacy of the treatment are limited. These observations, however, may encourage the initiation of prospective controlled studies using biodegradable controlled release implants as drug delivery systems for the treatment of inner ear diseases.

[Vestibular schwannomas - baseline and progress diagnostics]

Vestibular (vestibulocochlear) schwannomas are rare, benign schwannomas of the cerebellopontine angle, the internal auditory canal, or the inner ear. They can occur with or without clinical symptoms. The most common symptoms are unilateral or side-differentiated hearing loss with or without tinnitus and balance disorders. Initial symptomatology is nonspecific in the basic functional diagnosis, raising the question of when a hearing or balance disorder should be thought of as a differential diagnosis of vestibular schwannoma and what diagnostic pathway is appropriate. This concerns not only the confirmation of the diagnosis and the recording of all dysfunctions of the involved cranial nerves in the initial basic diagnostics, but also the procedure in the course and follow-up diagnostics - especially in patients who are subject to an observation strategy. Today, imaging alone is no longer sufficient for differentiated and individualized patient counseling. Due to the increasing detection of smaller tumors on MRI and the growing proportion of nearly asymptomatic patients, a shift in thinking from pure imaging monitoring to a detailed analysis of auditory and vestibular function is timely. In this educational article, diagnostic pathways for a sufficient patient consultation will be compiled. Ultimately, functional examination techniques from follow-up and progression diagnostics will also be included.

[Improvement of cochleovestibular function in chronic non-inflammatory perilymphatic fistulas of the labyrinth windows: cases from practice]

After a brief discussion of the problem of idiopathic sensorineural hearing loss and perilymphatic fistulas of the labyrinth windows, audiometric tests are identified that are informative for the preoperative diagnosis of the latter. Taking into account the own results of surgical treatment, attention is drawn to the feasibility of a wider use of exploratory tympanotomy in cases of suspected occurrence of perilymphatic fistulas of the labyrinth windows.

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

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

[Glucocorticosteroids in the treatment of acute neurosensory hearing loss. The current state of the problem. Part 2]

Modern literature data are presented on the choice of a drug for hormonal therapy in acute neurosensory hearing loss of various origins, the doses used for systemic therapy, the features and methods of intratympanic administration of glucocorticosteroids, and the evaluation of the effectiveness of treatment with this group of drugs.

Illness experience and coping styles of young and middle-aged patients with sudden sensorineural hearing loss: a qualitative study

Background

The incidence of Sudden Sensorineural Hearing Loss (SSNHL) is increasing and tends to occur at a young age. The patient’s disease experience during treatment is related to their physical and mental health. Effective coping styles such as proactively solving problems and asking for help will alleviate the patients’ psychological symptoms and improve their quality of life.

Aims and objectives

To explore the illness experience and coping styles of young and middle-aged patients with SSNHL (age: 18–64 years), clarify the relationship between the two, and understand the psychological state and needs of the patients.

Methods

The purposive and maximum difference sampling method was used to conduct semi-structured interviews with 23 young and middle-aged SSNHL patients. The interview data were analyzed by Colaizzi’s seven-step analysis.

Results

The illness experience of young and middle-aged SSNHL patients was complex, including symptoms during the onset of deafness and emotional experience before and after diagnosis. The coping styles of young and middle-aged SSNHL patients were active and diverse, including active acquisition of information, change in living habits, and seeking the care and attention of medical staff. Illness experience and coping style influence each other: good illness experience leads to active coping styles; active coping style results in good illness experience.

Conclusions

The illness experience of young and middle-aged SSNHL patients includes not only physical symptoms, but also changes in psychological and emotional reactions. Good illness experience can lead patients to adopt active coping style. Active and effective coping styles, such as positive acquisition of information, change in living habits and seeking care and help, can improve patients’ illness experience.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-021-06763-z.

Prognostic Value of Early Magnetic Resonance Imaging Patterns in Sudden Hearing Loss

INTRODUCTION

Sudden sensorineural hearing loss (SSHL) is a relatively frequent disease, but a sensitive marker or a reliable test to identify the underlying cause is still unavailable. Neuroradiology appears to offer the most promising tools, especially magnetic resonance imaging (MRI). In a recent study from our group, we explored the ability of MRI to detect subtle changes in the inner ear compartments by means of a 3D-fluid-attenuated inversion recovery sequence, aiming at identifying 3 distinct MRI patterns (haemorrhagic, inflammatory, brain-labyrinth barrier breakdown). In the present study, we contrasted the MRI patterns at onset with relevant prognostic factors, with the audiological features of each patient's SSHL and with treatment outcomes.

METHODS

In this retrospective study, we enrolled 50 adult subjects (54.61 ± 18.26 years) with SSHL. They underwent an MRI within 72 h from admission, and 5 audiological evaluations: at admission, on the 5th day after the start of medical therapy, at the end of the first cycle of hyperbaric oxygen therapy, then 1 and 6 months later.

RESULTS

Abnormalities of the MRI signal and/or post-contrast enhancement asymmetry of the cochlea ("pattern+ MRI") correlated with worse audiological outcomes at 1 month, but the different MRI patterns were not correlated with any specific prognostic model, despite rigid protocol settings. However, a significant difference was found for low-tone SSHL, which were always "pattern" negative at MRI (p = 0.01), and for profound SSHL which demonstrated a pattern+ MRI in 80% (p = 0.04). At the onset of SSHL, a pattern+ MRI was found in 29/50 cases (58.0%) and was related with lesser degree of recovery of pure-tone average at 1 month and lesser chance to retain the hearing threshold benefit in the long term. Given the limited numbers of patients enrolled so far, the relative impact of comorbidities on each MRI pattern remains uncertain. At 6 months, we observed a trend of greater and more stable recovery (p = 0.023) and less frequent recurrence of SSHL in patients with a normal MRI.

CONCLUSIONS

The 3 observed MRI patterns did not correlate consistently with specific audio-vestibular features or any peculiar aspect of the patient's clinical history. Larger series of patients with SSHL are needed, possibly from multicentric studies.

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.

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

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

Sudden sensorineural hearing loss - A contemporary review of management issues

Sudden sensorineural hearing loss (SSNHL) is an enigmatic entity, with obscure pathophysiology and debatable efficacy of the treatment agents used. An underlying cause is identified in only 10-15% of cases. The management of the remaining patients, classified as 'idiopathic', is empirical, and is conventionally with systemic steroids, vasodilator therapy, rheological agents, and antioxidants, to list a few amongst the host of the agents employed for the treatment. The availability of conflicting outcomes and lack of conclusive evidence has resulted in the propagation of consensus-based treatment protocols. In the present review, we discuss the various controversial issues and newer developments in the management of idiopathic SSNHL. The current review aims to present a narrative outlook of the updated evidence base available from PUBMED, augmented with relevant designated publications.

The Price of Immune Responses and the Role of Vitamin D in the Inner Ear

OBJECTIVE

In this review the authors discuss evidence from the literature concerning vitamin D and temporal bone diseases (benign paroxysmal positional vertigo [BPPV], Menière's disease [MD], vestibular neuritis, idiopathic facial paralysis, idiopathic acute hearing loss). Common features shared by Menière's disease, glaucoma, and the possible influence by vitamin D are briefly discussed.

DATA SOURCES, STUDY SELECTION

Publications from 1970 until recent times have been reviewed according to a keyword search (see above) in PubMed.

CONCLUSIONS

MD, BPPV, vestibular neuritis, idiopathic facial paralysis, idiopathic acute hearing loss may all have several etiological factors, but a common feature of the current theories is that an initial viral infection and a subsequent autoimmune/autoinflammatory reaction might be involved. Additionally, in some of these entities varying degrees of demyelination have been documented. Given the immunomodulatory effect of vitamin D, we postulate that it may play a role in suppressing an eventual postviral autoimmune reaction. This beneficial effect may be enhanced by the antioxidative activity of vitamin D and its potential in stabilizing endothelial cells. The association of vitamin D deficiency with demyelination has already been established in other entities such as multiple sclerosis and experimental autoimmune encephalitis. Mice without vitamin D receptor show degenerative features in inner ear ganglia, hair cells, as well as otoconia. The authors suggest further studies concerning the role of vitamin D deficiency in diseases of the temporal bone. Additionally, the possible presence and degree of demyelination in these entities will have to be elucidated more systematically in the future.

Healthy lifestyle consultation based on traditional Chinese medicine versus routine patient education in the treatment of idiopathic sudden sensorineural hearing loss after failure of systemic therapy: study protocol for a clinical randomised trial

Background

Idiopathic sudden sensorineural hearing loss (ISSNHL) is a major cause of deafness. Despite the advances in systemic therapy, some cases of ISSNHL are untreated, because the exact ISSNHL aetiology is unclear. Traditional Chinese medicine (TCM) has been used to treat diseases for thousands of years and is popular and widely practiced in Asia. TCM includes guidance on a healthy lifestyle. In recent decades, the relationship between lifestyle and disease has been emphasised; an unhealthy lifestyle may lead to illnesses. Thus, this study aims to compare the efficacy of lifestyle modification based on TCM with the usual consultation of ISSNHL after failure of a 2-week systemic therapy to provide a scientific basis for clinical decisions.

Methods

This study is a clinical randomised trial that involves 56 patients diagnosed with ISSNHL but who have had incomplete recovery after initial management (at least 2 weeks of routine Western medical treatment). The study is performed in accordance with the sudden hearing loss clinical guideline of the American Academy of Otolaryngology–Head and Neck Surgery, published in 2012. Participants are randomly distributed into two groups: the healthy lifestyle modification group based on TCM and the control group (1:1 ratio). Patient follow-up lasts for 3 months. The primary outcome measure is the effective rate of hearing improvement, which is defined as the proportion of patients with at least 15 dB of improvement in the average thresholds of hearing loss frequency. The secondary outcome measures are improvements in word recognition score, Tinnitus Handicap Inventory and visual analogue scale for ear blockage and dizziness. Assessments are made at baseline and after lifestyle modification for 1 and 3 months.

Discussion

The efficacy of healthy lifestyle modification based on a TCM programme for patients with ISSNHL with incomplete recovery after failure of initial systemic therapy is determined in this trial. Positive results will provide clinical evidence on the effects of a TCM-based healthy lifestyle, which could be recommended as salvage therapy for patients with ISSNHL.

Trial registration

Chinese Clinical Trial Registry, ChiCTR-INR-17011459. Registered on 22 May 2017.

Untreated primary hypothyroidism with simultaneous rhabdomyolysis, pericardial effusion, and sudden sensorineural hearing loss: a case report

BACKGROUND

Hypothyroidism, one of the prevalent endocrine disorders worldwide, has a broad spectrum of clinical manifestations, from an asymptomatic condition to myxedema coma. Although the majority of patients with hypothyroidism have minor clinical symptoms, which are recovered with levothyroxine treatment, some patients occasionally do experience fatal complications. Here we report, for the first time, the case of a patient who had hypothyroidism with simultaneous occurrence of rhabdomyolysis with acute kidney injury, moderate pericardial effusion, and sudden sensorineural hearing loss.

CASE PRESENTATION

A 57-year-old man with a previous history of dyslipidemia and untreated hypothyroidism was admitted to the hospital due to shortness of breath, lethargy, lower extremity discomfort, and unilateral hearing loss. Laboratory results revealed rhabdomyolysis with acute kidney injury and severe hypothyroidism. We detected cardiomegaly without lung parenchymal infiltration on chest radiography and moderate pericardial effusion on transthoracic echocardiography. We performed pure tone audiometry and identified profound unilateral sensorineural hearing loss. Aggressive fluid resuscitation, levothyroxine treatment, and systemic and intratympanic steroid therapy alleviated the patient's severe hypothyroidism, rhabdomyolysis, and pericardial effusion; however, sensorineural hearing loss was not fully recovered.

CONCLUSIONS

Early recognition of life-threatening complications is important in patients with severe hypothyroidism to prevent adverse outcomes. This case suggests that hypothyroidism should be considered in patients who have rhabdomyolysis with acute kidney disease and pericardial effusion. Moreover, sudden sensorineural hearing loss should be kept in mind as a rare complication of hypothyroidism.

MR evaluation of encephalic leukoaraiosis in sudden sensorineural hearing loss (SSNHL) patients

Epidemiological evidence suggests a strict correlation between sudden sensorineural hearing loss (SSNHL) and cerebrovascular disorders. Leukoaraiosis represents a diffuse alteration of the periventricular and subcortical white matter. The aim of our study was to verify if the presence of white matter hyperintensity (WMH) was higher in patients affected by SSNHL compared to controls and evaluate the correlation between WMH and the cardiovascular risk factors, hearing level, and the response to therapy in SSNHL patients. The study group included 36 subjects affected by unilateral SSNHL. Thirty-six age- and sex-matched normal subjects with a negative history of SSNHL were used as controls. All patients underwent magnetic resonance imaging (MRI) (1.5 Tesla GE Signa) and the extent of leukoaraiosis was assessed with the Fazekas scale. The results of the present study demonstrate a high prevalence of WMH in SSNHL patients compared to controls confirming the hypothesis of a vascular impairment in SSNHL patients. The higher recovery rate in patients with greater periventricular white matter hyperintensity (PWMH) may suggest a vascular etiology that is still responsive to medical treatment. We aim to expand both the number of patients and the controls to avoid the limitation of the still small number to warrant solid scientific conclusions.