Sudden sensorineural hearing loss: a review of diagnosis, treatment, and prognosis

Prognosis of Bilateral Sudden Sensorineural Hearing Loss: A Systematic Review and Meta-Analysis

OBJECTIVES

To comprehensively examine the characteristics and prognosis of bilateral sudden sensorineural hearing loss (BSSHL) and its subtypes compared to unilateral sudden sensorineural hearing loss (USSHL).

DATA SOURCES

PubMed, Scopus, and CINAHL.

REVIEW METHODS

Databases were searched from inception to December 5, 2023, for studies reporting patient characteristics and audiometric outcomes for BSSHL and its simultaneous (Si-BSSHL) and sequential (Se-BSSHL) subtypes. Meta-analysis of continuous measures, proportions (%), mean differences (Δ), and odds ratio (OR) were performed.

RESULTS

Eleven studies were included, consisting of 368 patients with BSSHL and 2,705 patients with USSHL. The pooled prevalence among all SSHL cases was 88.1% (95% CI: 81.2%-93.6%) for USSHL and 11.9% (95% CI: 6.4% to 18.8%) for BSSHL. PTA improvement following treatment with steroids was significantly worse in patients with BSSHL (Δ15.3 dB; 95% CI: 14.6 to 15.9; p < 0.0001) compared to patients with USSHL. There was no significant difference in post-treatment PTA improvement between the BSSHL subtypes. Patients with Si-BSSHL were significantly less likely to have an idiopathic etiology (OR: 0.4; 95% CI: 0.2 to 0.8; p = 0.01) and significantly more likely to have an autoimmune disease etiology (OR: 27.4; 95% CI: 2.2 to 336.1; p = 0.01), comorbid cardiovascular disease (OR: 2.3; 95% CI: 1.1 to 5.1; p = 0.03), and comorbid hypertension (OR: 2.5; 95% CI: 1.6 to 3.8; p < 0.0001) compared to patients with USSHL.

CONCLUSIONS

BSSHL is a considerably rarer form of SSHL with worse prognosis compared to USSHL. BSSHL, and Si-BSSHL in particular, has significantly greater associations with systemic pathologies compared to USSHL. Laryngoscope, 134:3883-3891, 2024.

Sudden Hearing Loss in the Active Duty Population: An Epidemiological Study

INTRODUCTION

Hearing loss among military personnel is a well-known challenge, reported as the second most common VA service-connected disability. Although most hearing loss occurs gradually, a subset occurs suddenly and significantly impacts quality of life and military readiness and is considered as a medical emergency. This study aims to evaluate the incidence of sudden hearing loss among different subpopulations within the military system to better identify at-risk groups.

MATERIALS AND METHODS

This study was a retrospective population-based study reviewing all cases of diagnosed sudden hearing loss between January 1, 2016 and December 31, 2021 within active duty service members in the U.S. DoD. Statistical analysis of multiple subpopulations was performed.

RESULTS

There were 2,650 cases of sudden hearing loss diagnosed in active duty service members during the study period, with an average incidence of 32.9 cases per 100,000 people per year, compared with 5 to 27 cases per 100,000 people per year reported in civilian populations. Senior officers demonstrated significantly increased rates of sudden hearing loss with 103.9 cases per 100,000 people per year, likely as a result of increased age, as did Air Force personnel with 45.1 cases per 100,000 people per year. There was no difference in incidence based on military occupational specialty, though service members located overseas were noted to have decreased incidence compared with those stationed within the USA. There was no significant difference during the years before coronavirus-19 pandemic (2016-2019) compared to the years following the start of the pandemic (2020-2021).

CONCLUSIONS

Sudden hearing loss appears to occur more frequently in military personnel than in the civilian population. The increased incidence in senior officers is likely driven by increased age, though further evaluation into the discrepancies between reported incidence of hearing loss among enlisted service members and officers is warranted. Although military occupational specialty did not demonstrate any significant difference in incidence, for thus far unknown reasons those in the Air Force demonstrated increased rates of sudden hearing loss. Although other potentially at-risk groups were identified, focused efforts to better understand contributing factors to elevated incidence in senior officers and Air Force personnel will help to better mitigate the incidence and effects of sudden hearing loss.

Characterization of the components in plasma EVs unveiling the link between EVs-derived complement C3 with the severity and initial treatment response of profound sudden sensorineural hearing loss

BACKGROUND

Sudden sensorineural hearing loss (SSNHL) is characterized by rapid, unexplained loss of hearing within a 72-hour period and exhibits a high incidence globally. Despite this, the outcomes of therapeutic interventions remain largely unpredictable, especially for those with profound hearing loss. Extracellular vesicles (EVs), nano-sized entities containing biological materials, are implicated in the development of numerous diseases. The specific relationship between EVs and both the severity and treatment effectiveness of SSNHL, however, is not well understood.

METHODS

This study involved the analysis of medical records from the Department of Otolaryngology (September 1, 2020 - December 31, 2022) of patients diagnosed with SSNHL according to the 2015 Guidelines for Diagnosis and Treatment of Sudden Deafness in China. Peripheral blood samples from patients with various types of SSNHL before and after treatment were collected, alongside samples from healthy volunteers serving as controls. Plasma EVs were isolated using gel rejection chromatography and analyzed for concentration, marker presence, and morphology using Nanosight, Western blot, and transmission electron microscopy (TEM), respectively. Proteomics and miRNA assessments were conducted to identify differentially expressed proteins and miRNAs in the plasma EVs of SSNHL patients and healthy volunteers. Key proteins were further validated through Western blot analysis. Enzyme-linked immunosorbent assay (ELISA) was utilized to determine the levels of complement C3 in plasma EVs, and correlation analyses were performed with audiological data pre- and post-treatment.

RESULTS

Plasma from SSNHL patients of varying types was collected and their EVs were successfully isolated and characterized. Proteomic analysis revealed that complement C3 levels in the plasma EVs of patients with profound SSNHL were significantly higher compared to healthy controls. Differential expression of miRNAs in plasma EVs and their related functions were also identified. The study found that the level of complement C3 in plasma EVs, but not the total plasma complement C3, positively correlated with the severity of SSNHL in patients exhibiting positive therapeutic responses, particularly in those with initially lower levels of EV-associated complement C3. After treatment, complement C3 level was decreased in patients with initially higher levels of EV-associated complement C3. No significant correlation was observed between changes in plasma EV-derived complement C3 levels and the degree of hearing loss in either responders or non-responders among patients with profound SSNHL.

CONCLUSION

Differential profiles of proteins and miRNAs were identified in patients with profound SSNHL. Notably, plasma EV-derived complement C3 was linked to both the severity and early treatment effectiveness of patients with profound SSNHL.

Biomaterials as a new option for treating sensorineural hearing loss

Sensorineural hearing loss (SNHL) usually involves damage to complex auditory pathways such as inner ear cells and auditory nerves. The highly intricate and nuanced characteristics of these cells render their repair and regeneration extremely challenging, making it difficult to restore hearing to normal levels once it has been compromised. The effectiveness of traditional drugs is so minimal that they provide little help with the treatment. Fortunately, extensive experiments have demonstrated that combining biomaterials with conventional techniques significantly enhances drug effectiveness. This article reviews the research progress of biomaterials in protecting hair cells and the auditory nerve, repairing genes related to hearing, and developing artificial cochlear materials. By organizing the knowledge presented in this article, perhaps new insights can be provided for the clinical management of SNHL.

Prognosis Prediction of Sudden Sensorineural Hearing Loss Using Ensemble Artificial Intelligence Learning Models

OBJECTIVE

We used simple variables to construct prognostic prediction ensemble learning models for patients with sudden sensorineural hearing loss (SSNHL).

STUDY DESIGN

Retrospectively study.

SETTING

Tertiary medical center.

PATIENTS

1,572 patients with SSNHL.

INTERVENTION

Prognostic.

MAIN OUTCOME MEASURES

We selected four variables, namely, age, days after onset of hearing loss, vertigo, and type of hearing loss. We also compared the accuracy between different ensemble learning models based on the boosting, bagging, AdaBoost, and stacking algorithms.

RESULTS

We enrolled 1,572 patients with SSNHL; 73.5% of them showed improving and 26.5% did not. Significant between-group differences were noted in terms of age ( p = 0.011), days after onset of hearing loss ( p < 0.001), and concurrent vertigo ( p < 0.001), indicating that the patients who showed improving to treatment were younger and had fewer days after onset and fewer vertigo symptoms. Among ensemble learning models, the AdaBoost algorithm, compared with the other algorithms, achieved higher accuracy (82.89%), higher precision (86.66%), a higher F1 score (89.20), and a larger area under the receiver operating characteristics curve (0.79), as indicated by test results of a dataset with 10 independent runs. Furthermore, Gini scores indicated that age and days after onset are two key parameters of the predictive model.

CONCLUSIONS

The AdaBoost model is an effective model for predicting SSNHL. The use of simple parameters can increase its practicality and applicability in remote medical care. Moreover, age may be a key factor influencing prognosis.

Three-dimensional heavily T2-weighted FLAIR in the detection of blood-labyrinthine barrier leakage in patients with sudden sensorineural hearing loss: comparison with T1 sequences and application of deep learning-based reconstruction

OBJECTIVE

Blood-labyrinthine barrier leakage has been reported in sudden sensorineural hearing loss (SSNHL). We compared immediate post-contrast 3D heavily T2-weighted fluid-attenuated inversion recovery (FLAIR), T1 spin echo (SE), and 3D T1 gradient echo (GRE) sequences, and heavily T2-weighted FLAIR (hvT2F) with and without deep learning-based reconstruction (DLR) in detecting perilymphatic enhancement.

METHODS

Fifty-four patients with unilateral SSNHL who underwent ear MRI with three sequences were included. We compared asymmetry scores, confidence scores, and detection rates of perilymphatic enhancement among the three sequences and obtained 3D hvT2F with DLR from 35 patients. The above parameters and subjective image quality between 3D hvT2F with and without DLR were compared.

RESULTS

Asymmetry scores and detection rate of 3D hvT2F were significantly higher than 3D GRE T1 and SE T1 (respectively, 1.37, 0.11, 0.19; p < 0.001). Asymmetry scores significantly increased with DLR compared to 3D hvT2F for experienced and inexperienced readers (respectively, 1.77 vs. 1.40, p = 0.036; 1.49 vs. 1.03, p = 0.012). The detection rate significantly increased only for the latter (57.1% vs. 31.4%, p = 0.022). Patients with perilymphatic enhancement had significantly higher air conduction thresholds on initial (77.96 vs. 57.79, p = 0.002) and 5 days after presentation (63.38 vs. 41.85, p = 0.019).

CONCLUSION

3D hvT2F significantly increased the detectability of perilymphatic enhancement compared to 3D GRE T1 and SE T1. DLR further improved the conspicuity of perilymphatic enhancement in 3D hvT2F. 3D hvT2F and DLR are useful for evaluating blood-labyrinthine barrier leakage; furthermore, they might provide prognostic value in the early post-treatment period.

CLINICAL RELEVANCE STATEMENT

Ten-minute post-contrast 3D heavily T2-weighed FLAIR imaging is a potentially efficacious sequence in demonstrating perilymphatic enhancement in patients with sudden sensorineural hearing loss and may be further improved by deep learning-based reconstruction.

KEY POINTS

• 3D heavily T2-weighted FLAIR (3D hvT2F) is a sequence sensitive in detecting low concentrations of contrast in the perilymphatic space. • 3D hvT2F sequences properly demonstrated perilymphatic enhancement in sudden sensorineural hearing loss compared to T1 sequences and were further improved by deep learning-based reconstruction (DLR). • 3D hvT2F and DLR are efficacious sequences in detecting blood-labyrinthine barrier leakage and with potential prognostic information.

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.

Recovery rate after acute acoustic trauma: a case series and meta-analysis

OBJECTIVE

Steroids given systemically, locally, or both are the mainstay of treatment for acute acoustic trauma (AAT). The overall recovery rate (full, partial, and none) is undetermined.

STUDY DESIGN

Original case series and systematic literature review.

SETTING

Case series of a tertiary referral center and a systematic literature review.

METHODS

Cases of AAT between 2012 and 2022 were retrospectively analyzed for demographics, acoustic trauma characteristics, treatment modality and delay and prognosis. This case series was added to the series identified by a systematic literature review. This review included "Medline" via "PubMed", "EMBASE", and "Google scholar". All series were pooled for meta-analysis defining prognosis following steroidal treatment for AAT patients.

RESULTS

The pooled analyses included 662 ears, out of which 250 underwent complete recovery of hearing (overall proportion = 0.2809, 95%confidence interval [CI] = 0.1611-0.4178). Any recovery was recorded for 477 ears (overall proportion = 0.7185, 95% CI = 0.5671-0.8493) and no recovery was documented for 185 ears (overall proportion = 0.2815, 95% CI = 0.1507-0.4329).

CONCLUSION

The rate of overall recovery for AAT is around 70%, and around 30% for full recovery when steroids are initiated within the first 2 weeks following the insult.

LEVEL OF EVIDENCE: 3

Impact of audiovestibular factors on prognosis in patients with sudden sensorineural hearing loss without vertigo

PURPOSE

This study aimed to investigate the hearing outcomes in patients with sudden sensorineural hearing loss without vertigo (SSNHLwoV).

METHODS

Patients with SSNHLwoV managed from December 2016 to March 2020 were prospectively enrolled in an academic tertiary referral center. Fifty-one patients with SSNHLwoV who completed high-dose steroid treatment. The hearing prognosis was analyzed using a multivariate Cox regression model.

RESULTS

The rates of complete, partial, and no hearing recovery were 52.9%, 17.6%, and 29.4% in patients with SSNHLwoV, respectively. The video head impulse test (vHIT) of the posterior semicircular canal (PSC), high-tone hearing loss (4-8 kHz) ≥ 30 dB, and average hearing threshold (0.5-1-2-4 kHz) were significantly associated with incomplete recovery of hearing after treatment. In multivariate analysis, the vHIT of the PSC (hazard ratio [HR], 14.502; 95% confidence interval [CI], 1.371-153.355) and high-tone hearing loss ≥ 30 dB (HR, 9.170; 95% CI, 2.283-36.830) remained robust.

CONCLUSIONS

Abnormal vestibular function tests were performed in 80.4% of the patients with SSNHLwoV. Abnormal vHIT of the PSC and high-tone hearing loss ≥ 30 dB were independent factors resulting in incomplete recovery of hearing in patients with SSNHLwoV. In the SSNHLwoV cohort, the caloric test was not significantly associated with hearing prognosis, and vHIT was a feasible predictor of treatment outcome.

Access to Sudden Hearing Loss Care at Urgent Care Centers

OBJECTIVES

To compare patient access to urgent care centers (UCCs) with a diagnosis of sudden hearing loss based on insurance.

METHODS

One hundred twenty-five random UCCs in states with Medicaid expansion and 125 random UCCs in states without Medicaid expansion were contacted by a research assistant posing as a family member seeking care on behalf of a patient with a one-week history of sudden, unilateral hearing loss. Each clinic was called once as a Medicaid patient and once as a private insurance (PI) patient for 500 total calls. Each phone encounter was evaluated for insurance acceptance and self-pay price. Secondary outcomes included other measures of timely/accessible care. Chi-square/McNemar's tests and independent/paired sample t-tests were performed to determine whether there were statistically significant differences between expansion status and insurance type. Calls ended before answering questions were not included in the analysis.

RESULTS

Medicaid acceptance rate was significantly lower than PI (68.1% vs. 98.4%, p < 0.001). UCCs in Medicaid expansion states were significantly more likely to accept Medicaid (76.8% vs. 59.2%, p = 0.003). The mean wage-adjusted self-pay price was significantly greater in states with Medicaid expansion at $169.84 than in states without at $145.34 when called as a Medicaid patient (mean difference: $24.50, 95% Confidence Interval: $0.45-$48.54, p = 0.046). The rates of referral to an emergency department and self-pay price nondisclosure rates were greater for Medicaid calls than for private insurance calls (8.2% vs. 0.4% and 17.4% vs. 5.8%; p < 0.001 for both).

CONCLUSION

Medicaid patients with otologic emergencies face reduced access to care at UCCs.

LEVEL OF EVIDENCE

NA Laryngoscope, 2024.

Assessment of Peripheral and Central Auditory Processing after Treatment for Idiopathic Sudden Sensorineural Hearing Loss

Introduction  When cases of idiopathic sudden sensorineural hearing loss (SSNHL) are treated successfully, most clinicians assume the normality and symmetry of the auditory processing. This assumption is based on the recovery of the detection ability on the part of the patients, but the auditory processing involves much more than detection alone. Since certain studies have suggested a possible involvement of the central auditory system during the acute phase of sudden hearing loss, the present study hypothesized that auditory processing would be asymmetric in people who have experienced sudden hearing loss. Objective  To assess the physiologic and electrophysiological conditions of the cochlea and central auditory system, as well as behavioral discrimination, of three primary aspects of sound (intensity, frequency, and time) in subjects with normal ears and ears treated successfully for SSNHL. Methods  The study included 19 SSNHL patients whose normal and treated ears were assessed for otoacoustic emissions, speech auditory brainstem response, intensity and pitch discrimination, and temporal resolution in a within-subject design. Results  The otoacoustic emissions were poorer in the treated ears compared to the normal ears. Ear- and sex-dependent differences were observed regarding otoacoustic emissions and pitch discrimination. Conclusion  The asymmetrical processing observed in the present study was not consistent with the hearing threshold values, which might suggest that the central auditory system would be affected regardless of the status of the peripheral hearing. Further experiments with larger samples, different recovery scenarios after treatment, and other assessments are required.

Predicting Sudden Sensorineural Hearing Loss Recovery with Patient-Personalized Seigel's Criteria Using Machine Learning

BACKGROUND

Accurate prognostic prediction is crucial for managing Idiopathic Sudden Sensorineural Hearing Loss (ISSHL). Previous studies developing ISSHL prognosis models often overlooked individual variability in hearing damage by relying on fixed frequency domains. This study aims to develop models predicting ISSHL prognosis one month after treatment, focusing on patient-specific hearing impairments.

METHODS

Patient-Personalized Seigel's Criteria (PPSC) were developed considering patient-specific hearing impairment related to ISSHL criteria. We performed a statistical test to assess the shift in the recovery assessment when applying PPSC. The utilized dataset of 581 patients comprised demographic information, health records, laboratory testing, onset and treatment, and hearing levels. To reduce the model's reliance on hearing level features, we used only the averages of hearing levels of the impaired frequencies. Then, model development, evaluation, and interpretation proceeded.

RESULTS

The chi-square test (p-value: 0.106) indicated that the shift in recovery assessment is not statistically significant. The soft-voting ensemble model was most effective, achieving an Area Under the Receiver Operating Characteristic Curve (AUROC) of 0.864 (95% CI: 0.801-0.927), with model interpretation based on the SHapley Additive exPlanations value.

CONCLUSIONS

With PPSC, providing a hearing assessment comparable to traditional Seigel's criteria, the developed models successfully predicted ISSHL recovery one month post-treatment by considering patient-specific impairments.

Focus on the effect of nursing care combined with cognitive intervention and functional training on negative emotion, compliance and quality of life in elderly patients with sudden deafness: A retrospective study

To explore the effects of focused solution nursing combined with cognitive intervention combined with functional training on negative emotions, compliance and quality of life in elderly patients with sudden deafness. A total of 160 patients with sudden deafness in the elderly who were treated in our hospital from January 2019 to May 2021 were selected as the objects of this retrospective study. Based on different treatment approaches, subjects were divided into a control group and an observation group. Due to reasons such as the COVID-19 pandemic and transfers, 10 cases were lost to follow-up. In total, 75 cases were ultimately lost from both the control and observation groups. The control group implements cognitive intervention and functional training, and the observation group adopts focused solution nursing care on the basis of the control group. Observe and compare the effects of negative emotions, psychological distress, air conduction threshold level, compliance and quality of life of the 2 groups of patients. The air conduction hearing threshold level of the 2 groups of patients after nursing was lower than that before nursing and the observation group was lower than the control group. The positive coping scores of the 2 groups were significantly increased, and the negative coping scores were both significantly reduced and the observation group was in the 2 indicators. The degree of change was greater than that of the control group (P < .05). After nursing, the self-rating anxiety scale (SAS) and self-rating depression scale (SDS) of the observation group were lower than those of the control group (P < .05). The mental vitality score, social interaction score, emotional restriction score, and mental status of the observation group were significantly higher than those of the control group. The observation group's psychological compliance, activity compliance, dietary compliance, and treatment protocol compliance were significantly higher than those of the control group (P < .05). Adopting the focused solution model of nursing care can provide a better nursing recovery for elderly patients with sudden deafness, significantly improve the patient quality of life and anxiety and depression, improve patient compliance with treatment, and provide a certain reference for the nursing of elderly patients with sudden deafness.

Sudden Sensorineural Hearing Loss in Patients Aged from 15 to 40 Years

Objectives: The purpose of this study was to investigate the hearing characteristics and causes of sudden sensorineural hearing loss (SSNHL) in patients aged from 15 to 40 years, focusing on audiological outcomes one year after the diagnosis. Methods: The medical records of individuals with SSNHL who were referred to our tertiary-level audiologic center were reviewed. All patients had undergone comprehensive diagnostic evaluations, including high-resolution 3D-FLAIR delayed magnetic resonance imaging (MRI), cone beam computed tomography (CBCT), and screening for coagulation, infectious, and autoimmune diseases. Results: Overall, 56 patients (mean age 28.1 ± 7.6 years) were included in the study. The hearing threshold in the affected ear improved significantly from 56.0 ± 18.0 dB at the diagnosis to 46.9 ± 22.3 dB after one year (p = 0.02). The degree of hearing loss, audiometric configurations, hearing improvements, and adherence to hearing treatments showed considerable variability among patients. Aural fullness, tinnitus, and hyperacusis were the predominant symptoms associated with SSNHL, and their prevalence decreased significantly over time. The diagnostic protocol led to the identification of the specific cause of SSNHL in 75% (42/56) of patients. The known etiology was found to be otological (39.3%), infectious (21.4%), autoimmune (7.1%), vascular (5.4%), or neoplastic (1.8%). In particular, Menière's disease (n = 12), isolated cochlear endolymphatic hydrops (n = 6), HSV-1 (n = 5), and EBV (n = 4) infections were the most frequent causes of SSNHL. Conclusions: The identification of the specific etiology of SSNHL may facilitate a more personalized approach to management and treatment.

Complementary acupuncture treatment and reduced risk of sudden sensorineural hearing loss in nasopharyngeal carcinoma patients: a retrospective, nested case-control study

PURPOSE

Hearing loss is a frequently observed comorbidity in patients with nasopharyngeal carcinoma (NPC). Accumulating evidence demonstrated that acupuncture can safely manage cancer and its treatment-related symptoms, but its effect in minimizing the likelihood of experiencing sudden sensorineural hearing loss (SSHL) has not been established. So this work aimed to determine the risk of SSHL among NPC persons with or without acupuncture use.

METHODS

One population-level, nested case-control design within a cohort study is employed. Relevant information on persons aged 20-80 years who were afflicted with NPC between 2000 and 2010 was extracted from a nationwide health claims database. From them, we identified the cases who had the first SSHL diagnosis occurring after NPC, and all of them were randomly matched to two controls without SSHL. Conditional logistic regression was employed to calculate odds ratios (OR) and its respective 95% confidence intervals (CI) for incident SSHL in relation to acupuncture treatment.

RESULTS

Eight hundred eleven SSHL cases were randomly matched to 1452 controls. Those receiving conventional care plus acupuncture use had a reduced adjusted OR of 0.39 (95% CI, 0.25-0.60) for SSHL. We further discovered that the longer usage of acupuncture remarkably correlated with reduction of SSHL risk in a dose-dependent manner.

CONCLUSIONS

Delineation of the benefit from integration of acupuncture into conventional care may be a reference in instituting more appropriate care for NPC subjects.

IMPLICATIONS FOR CANCER SURVIVORS

Patients living with NPC may benefit from a timely integration of acupuncture into routine care to lessen SSHL risk.

Association of sudden sensorineural hearing loss with meteorological factors: a time series study in Hefei, China, and a literature review

Air pollution can cause disease and has become a major global environmental problem. It is currently believed that air pollution may be related to the progression of SSNHL. As a rapidly developing city in recent years, Hefei has serious air pollution. In order to explore the correlation between meteorological variables and SSNHL admissions, we conducted this study. This study investigated the short-term associations between SSNHL patients admitted to the hospital and Hefei climatic variables. The daily data on SSNHL-related hospital admissions and meteorological variables containing mean temperature (T-mean; °C), diurnal temperature range (DTR; °C), atmospheric pressure (AP; Hp), and relative humidity (RH; %), from 2014 to 2021 (2558 days), were collected. A time-series analysis integrating distributed lag non-linear models and generalized linear models was used. PubMed, Embase, Cochrane Library, and Web of Science databases were searched. Literature published up to August 2023 was reviewed to explore the potential impact mechanisms of meteorological factors on SSNHL. The mechanisms were determined in detail, focusing on wind speed, air pressure, temperature, humidity, and air pollutants. Using a median of 50.00% as a baseline, the effect of exceedingly low T-mean in the single-day hysteresis effect model began at a lag of 8 days (RR = 1.032, 95% CI: 1.001 ~ 1.064). High DTR affected the admission rate for SSNHL on lag 0 day. The significance of the effect was the greatest on that day (RR = 1.054, 95% CI: 1.007 ~ 1.104) and then gradually decreased. High and exceedingly high RH affected the admission rate SSNHL on lag 0 day, and these effects lasted for 8 and 7 days, respectively. There were significant associations between all grades of AP and SSNHL. This is the first study to assess the effect of meteorological variables on SSNHL-related admissions in China using a time-series approach. Long-term exposures to high DTR, RH values, low T-mean values, and all AP grades enhance the incidence of SSNHL in residents. Limiting exposure to extremes of ambient temperature and humidity may reduce the number of SSNHL-related hospital visits in the region. It is advisable to maintain a suitable living environment temperature and avoid extreme temperature fluctuations and high humidity. During periods of high air pollution, it is recommended to stay indoors and refrain from outdoor exercise.

White Matter Hyperintensity in Patients with Sudden Sensorineural Hearing Loss

OBJECTIVE

To compare white matter hyperintensities (WMHs) on T2-weighted magnetic resonance imaging (MRI) of patients with sudden sensorineural hearing loss (SSNHL) and analyze subpopulations with age-matched controls.

METHODS

T2-weighted MRI scans of 150 patients with SSNHL were assessed for WMHs and compared with the data of 148 healthy age-matched adults. Assessments of WMHs included independent grading of deep white matter hyperintensities (DWMHs) and periventricular hyperintensities (PVHs). WMH severity was visually rated using the Fazekas and Mirsen scales by two independent observers.

RESULTS

Fazekas grades for PVHs (p < 0.001) and DWMHs (p < 0.001) of SSNHL patients were found to be significantly greater than those of healthy participants. The average Mirsen grades for DWMHs of healthy and SSNHL patients were evaluated to be 0.373 ± 0.550 and 2.140 ± 0.859, respectively. Mirsen grades for DWMHs of SSNHL patients were found to be significantly greater (p < 0.001) than those of healthy participants. The Mirsen scale was found to have higher sensitivity (p < 0.001) than the Fazekas scale in grading PVHs and DWMHs. No significant difference (p = 0.24) was found in specificities between the two scales.

CONCLUSIONS

Patients with sudden hearing loss have a much higher likelihood of having periventricular and deep white matter hyperintensities compared to age-matched controls. These findings indicate that sudden hearing loss patients are more likely to have microvascular changes in the brain, which may indicate a vascular and/or migraine origin to sudden sensorineural hearing loss.

Bilateral sudden sensorineural hearing loss in patient with Behçet disease

Bacckground: Approximately 80% to 85% of sudden sensorineural hearing loss (SSNHL) is idiopathic, but immune-mediated mechanisms are thought to be involved. Behçet disease is an autoinflammatory vasculitis that may involve vessels of the inner ear. It can cause sensorineural hearing loss (SNHL) and an increased risk of SSNHL. Study Sample: We report a 21-year-old man who was diagnosed with Behçet disease in childhood and presented to our clinic with a 10-day history of abrupt hearing deterioration in both ears. Pure-tone audiometry showed severe to profound bilateral SNHL. Results: Oral prednisolone was prescribed for 3 weeks. Concurrent intratympanic steroid injections (ITSIs) were administered in each ear every 2 days for 5 days. A total of 15 daily sessions of hyperbaric oxygen therapy (HBOT) were completed. Acupuncture was performed every 2 days for 1 month. After these combined therapies, the patient's hearing threshold by 20 dB and his speech recognition threshold were improved. Conclusions: Some patients with SSNHL recover no hearing improvement after routine treatment, and alternative treatments including ITSI, HBOT, and acupuncture can be considered as optional. We used an aggressive multimodal approach to treat severe bilateral SSNHL in patient with Behçet disease.

The Roles Played by Blood Inflammatory Parameters in Sudden Sensorineural Hearing Loss

OBJECTIVE

The etiology of sudden sensorineural hearing loss (SSNHL) remains unknown; inflammation may be one cause. We retrospectively studied SSHNL cases in terms of the inflammatory parameters involved.

METHODS

We reviewed 169 SSNHL cases. The control group contained 132 patients with vocal cord polyps. The C-reactive protein (CRP) level, CRP/serum albumin (Alb) ratio, and neutrophil/lymphocyte ratio (NLR) were compared between the 2 groups. The relationships between these parameters and the time to treatment after SSHNL onset, hearing level, and therapeutic effects were also analyzed.

RESULTS

The CRP level, CRP/Alb ratio, and NLR were higher in SSNHL patients than in controls, but only the NLR differed significantly between the 2 groups. We found no significant differences between patients with different hearing levels, those evaluated at various times after SSNHL onset, and those with different outcomes.

CONCLUSION

The NLR is a reliable SSNHL diagnostic marker. The CRP level and CRP/Alb ratio are not useful indicators.

Causal role of immune cell phenotypes in idiopathic sudden sensorineural hearing loss: a bi-directional Mendelian randomization study

Background

A growing body of evidence suggests that immunological processes have a significant role in developing idiopathic sudden sensorineural hearing loss (SSHL). However, few studies have examined the association between immune cell phenotype and SSHL using Mendelian Randomization (MR).

Methods

The online genome-wide association studies (GWAS) database was used to compile data from GWAS covering 731 immunophenotypes and SSHL. Inverse variance weighted (IVW) analysis was primarily used for MR study, and single nucleotide polymorphisms (SNPs) associated with immunophenotypes served as dependent variables. A sensitivity study and the false discovery rate (FDR) correction were used to examine the MR hypothesis. In addition, the possibility of reverse causality between immunophenotype and SSHL was validated by reverse MR. Reverse MR was analyzed in a manner consistent with forward MR.

Results

After FDR correction and sensitivity analysis, we screened 7 immunophenotypes, including IgD+ CD38dim %lymphocyte (95% CI: 1.0019, 1.0742, p = 3.87 × 10-2, FDR = 1.15 × 10-2); Unsw mem AC (95% CI: 1.004, 1.2522, p = 4.23 × 10-2, FDR = 2.25 × 10-2); CD86+ myeloid DC AC (95% CI: 1.0083, 1.1147, p = 2.24 × 10-2, FDR = 4.27 × 10-2); CD33dim HLA DR- AC (95% CI: 1.0046, 1.0583, p = 2.12 × 10-2, FDR = 4.69 × 10-2); SSC-A on CD8br (95% CI: 1.0028, 1.1461, p = 4.12 × 10-2, FDR = 4.71 × 10-2); CD45RA- CD4+ %T cell (95% CI: 1.0036, 1.0503, p = 2.32 × 10-2, FDR = 4.82 × 10-2); DP (CD4+CD8+) AC (95% CI: 1.011, 1.2091, p = 2.78 × 10-2, FDR = 4.97 × 10-2). There was a strong causal relationship with SSHL onset, and the reliability of the results was verified. Furthermore, the immunological cell profile and SSHL did not appear to be closely associated, as shown by reverse MR analysis.

Conclusion

Our study provides more support for the current hypothesis that immunophenotypes and the pathophysiology of SSHL are closely associated. Further validation is needed to assess the role of these immunophenotypes in SSHL.

A prognostic value of estimated pulse wave velocity in idiopathic sudden sensorineural hearing loss

PURPOSE

Arterial stiffness, represented by estimated pulse wave velocity (ePWV), is the independent surrogate marker for cardiovascular event. The aim of the study was to investigate the significance of ePWV in the treatment outcome of idiopathic sudden sensorineural hearing loss (SSNHL).

METHODS

One hundred and ten patients with idiopathic SSNHL who hospitalized between April 2019 and March 2022 were evaluated. Arterial stiffness was calculated with formula for ePWV and other cardiovascular parameters of body mass index (BMI), and serum lipid level was determined. All patients received systemic high-dose steroid therapy and intratympanic steroid injections as a salvage management. Treatment outcome was assessed at 6 months after treatment, and classified as recovery and nonrecovery groups according to hearing recovery.

RESULTS

The initial pure-tone hearing threshold was 72.6 ± 23.8 dB and final hearing threshold was 52.63 ± 31.10 dB. After treatment, 60 (54.5%) patients included in recovery group and other 50 (45.5%) were classified as nonrecovery group. Age, days of onset to treatment, BMI, waist circumference, and ePWV were higher in the nonrecovery group compared to recovery group in univariate analysis (p = 0.039, p = 0.049, p = 0.003, p = 0.004, p = 0.007, respectively). In multivariate analysis, days of onset to treatment, BMI, and ePWV were associated with recovery (p = 0.030, p = 0.007, p = 0.022).

CONCLUSION

Higher ePWV, a measure of arterial stiffness, was associated with a poor hearing recovery of SSNHL.

The Effectiveness of Salvage Hyperbaric Oxygen Therapy Following Combined Steroid Therapy for Refractory Sudden Sensorineural Hearing Loss

OBJECTIVE

Hyperbaric oxygen therapy (HBOT) is an accepted treatment option for sudden sensorineural hearing loss (SSNHL), but it is still recommended in combination with corticosteroids. We investigated the efficacy of salvage HBOT in refractory SSNHL that does not respond to corticosteroid combination therapy.

METHODS

Eighty-four patients were included, who had unilateral SSNHL with an improvement of pure-tone average (PTA) less than 10 dB after using intratympanic plus systemic corticosteroids (combined therapy) as the initial therapy. The control group (n = 66) received no further treatment, and the HBOT group (n = 18) received additional treatment with HBOT (10 sessions in total with 2.5 atmospheres absolute for 1 hour).

RESULTS

No differences in PTA or WDS were found between the 2 groups. However, the mean hearing gain in the HBOT group (16.8 ± 4.49 dB) was significantly higher than that in the control group (4.45 ± 1.03 dB) (P = .015). The proportion of patients with hearing recovery (hearing gain of 10 dB or more) after treatment was significantly higher in HBOT group (38.9%) than in the control group (10.6%).

CONCLUSIONS

In patients with refractory SSNHL after steroid combined therapy, salvage HBOT showed a significant effect on hearing gain and recovery rate.

Normal Weight Central Obesity is a Poor Prognostic Factor for Sudden Sensorineural Hearing Loss

OBJECTIVES

To investigate the role of normal weight central obesity (NWCO) in the prognosis of sudden sensorineural hearing loss (SSNHL).

METHODS

We retrospectively investigated 807 cases of SSNHL from January of 2008 to August of 2019 from the Department of Otorhinolaryngology at Kaohsiung Medical University Hospital in southern Taiwan. We analyzed the association between overweight and obesity, NWCO, and the prognosis of SSNHL. The demographic and clinical characteristics, audiometry results, and outcomes were also reviewed.

RESULTS

The nonobese (body mass index [BMI] < 24 kg/m2) and overweight and obese groups (BMI ≥ 24 kg/m2) comprised 343 (42.50%) and 464 (57.50%) patients, respectively. The favorable prognosis rates in the nonobese and the overweight and obese groups were 45.48% and 45.91%, respectively, without a significant difference (P = .9048). Multivariate logistic regression revealed that BMI (adjusted odds ratio [aOR] = 1.00, 95% CI = 0.948-1.062, P = .9165) was not significantly associated with SSNHL recovery. The normal weight noncentral obesity (NWNCO) and NWCO groups comprised 266 (77.55%) and 77 (22.45%) patients, respectively, and had favorable prognosis rates of 48.50% and 35.06%, respectively. The difference between the groups was significant (P = .0371). Multivariate logistic regression analysis revealed that NWCO (aOR = 2.51, 95% CI = 1.292-5.019, P = .0075) was significantly associated with SSNHL recovery.

CONCLUSIONS

NWCO may significantly affect the prognosis of SSNHL.

A Scoping Review of Otologic Manifestations of Hematologic Malignancies

OBJECTIVE

To examine the otologic and neurotologic symptoms, physical examination findings, and imaging features secondary to hematologic malignancies.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, databases, including PubMed, Scopus, and CINAHL, were searched for articles including patients with otologic manifestations of leukemia, lymphoma and multiple myeloma. Data collected included patient and study demographics, specific hematologic malignancy, timing and classification of otologic symptoms, physical examination findings, imaging features and methods of diagnosis. Pooled descriptive analysis was performed.

RESULTS

Two hundred seventy-two articles, of which 255 (93.8%) were case reports and 17 (6.2%) were case series, reporting on 553 patients were identified. Otologic manifestations were reported on 307 patients with leukemia, 204 patients with lymphoma and 42 patients with multiple myeloma. Hearing loss and unilateral facial palsy were the most common presenting symptoms for 111 reported subjects with leukemia (n = 46, 41.4%; n = 43, 38.7%) and 90 with lymphoma (n = 38, 42.2%; n = 39, 43.3%). Hearing loss and otalgia were the most common presenting symptoms for 21 subjects with multiple myeloma (n = 10, 47.6%; n = 6, 28.6%). Hearing loss and unilateral facial palsy were the most common otologic symptoms indicative of relapse in subjects with leukemia (n = 14, 43.8%) and lymphoma (n = 5, 50%).

CONCLUSION

Hearing loss, facial palsy, and otalgia might be the first indication of a new diagnosis or relapse of leukemia, lymphoma, or multiple myeloma. Clinicians should have a heightened level of suspicion of malignant etiologies of otologic symptoms in patients with current or medical histories of these malignancies.

Lipids and sudden sensorineural hearing loss: A bidirectional two-sample Mendelian randomization analysis

OBJECTIVE

While numerous observational studies have indicated an association between lipids and Sudden Sensorineural Hearing Loss (SSNHL), it remains uncertain whether dyslipidemia serves as a causal risk factor for SSNHL. Our objective is to elucidate the potential causal relationship between lipid levels and SSNHL through Mendelian randomization analysis.

METHODS

The primary and secondary lipid data used in this study were sourced from the UK Biobank (UKBB) and the Global Lipid Genetics Consortium results (GLGC), respectively. These datasets were obtained from large, publicly available genome-wide association studies (GWAS). The outcome data for sudden sensorineural hearing loss (SSNHL) were acquired from the Finnegan Biobank, consisting of 1491 cases and 196,592 controls. Subsequently, both single-variable Mendelian randomization (SVMR) and multivariate Mendelian randomization (MVMR) methods were employed to evaluate the causal relationship between lipids and the occurrence of SSNHL.

RESULTS

Among the primary lipid data, SVMR analysis showed a significant correlation between high density lipoprotein cholesterol (HDL-C) (OR: 0.822, 95 %CI: 0.694-0.974, p = 0.023) and SSNHL, and triglycerides (TG) (OR: 0.997, 95 %CI: 0.836-1.188, p = 0.975), low density lipoprotein cholesterol (LDL-C) (OR: 1.067, 95 %CI: 0.861-1.322, p = 0.552) did not correlate with SSNHL. In the secondary lipid data, SVMR analysis showed that HDL-C (OR: 0.987, 95 %CI: 0.805-1.210, p = 0.903), TG (OR: 0.991, 95 %CI: 0.787-1.246, p = 0.937) and LDL-C (OR: 1.092, 95 % CI: 0.926-1.287, p = 0.294) did not correlate with SSNHL. MVMR analysis of the primary lipid data showed that HDL-cholesterol (OR: 0.755, 95 % CI: 0.596-0.956, p = 0.019) was significantly associated with SSNHL, while TG (OR: 0.808, 95 %CI: 0.611-1.068, p = 0.134) and LDL-C (OR: 1.146, 95 %CI: 0.869-1.511, p = 0.333) did not correlate with SSNHL, consistent with the results of SVMR. Inverse MR results showed that SSNHL did not correlate with TG (OR: 0.999, 95 %CI: 0.997-1.001, p = 0.835), HDL-C (OR: 1.001, 95 %CI: 0.998-1.003), LDL-C (OR: 0.999, 95 %CI: 0.997-1.002, p = 0.863).

CONCLUSIONS

Mendelian randomization (MR) results suggest that decreased serum HDL-C levels are an independent risk factor for SSNHL. Monitoring and focusing on lipid levels may be of value in the prevention and treatment of SSNHL.

Objective and subjective efficacy of hearing aids in patients with mild-to-moderate unilateral hearing loss: a prospective study

PURPOSE

In patients with unilateral sensorineural hearing loss (USNHL), we explored both objective functional audiological gains and subjective satisfaction, indicating when a unilateral hearing aid is valuable.

METHODS

Thirty-seven patients with mild-to-moderate USNHL (mean pure-tone thresholds between 25 and 70 dB) were prescribed unilateral hearing aids. Functional gain, the aided speech discrimination score (SDS), the Hearing in Noise Test (HINT) score, and the sound localization test score were collected, and a questionnaire (the Hearing Handicap Inventory for the Elderly, HHIE) completed after 1, 2, and 3 months of hearing aid use. We classified the participants as having 'no handicap' (HHIE < 17), 'mild-to-moderate handicap' (17-42), and 'significant handicap' (> 42).

RESULTS

The decrease in handicap afforded by unilateral hearing aids was largest in the 'significant handicap' group (the HHIE total score fell from 59.1 to 37.2; P = 0.007). There were no between-group differences in either functional gain or the aided SDS. Only the 'significant handicap' group evidenced an improved HINT score; the composite signal-to-noise ratio (SNR) fell from - 1.5 to - 2.2 dB [S/N] (P = 0.023). The HHIE usefully indicated when a hearing aid alleviated the discomfort of USNHL; patients with unaided HHIE scores ≥ 20 evidenced significant decreases in the composite SNR (- 1.7 to - 2.0 dB [S/N]; P = 0.045).

CONCLUSIONS

When considering whether to prescribe a unilateral hearing aid for patients with mild-to-moderate USNHL, it is helpful to use the HHIE to evaluate discomfort. If the total score is ≥ 20, a hearing aid is appropriate.

A Comprehensive Study on Sudden Deafness for Analyzing Their Clinical Characteristics and Prognostic Factors

Background: To study the factors associated with the prognosis of patients with sudden deafness to facilitate clinical treatment and improve efficacy. Methods: A total of 414 patients with sudden deafness treated in Zhenjiang First People's Hospital from January 2020 to December 2022 were chosen. Relevant data were gathered and the effectiveness of treatment was assessed by comparing hearing test results before and after hospital admission and divided into effective and ineffective groups, and the effectiveness of each factor was analyzed using univariate analysis, Spearman's correlation analysis, and multifactor logistic regression. Results: The 2 groups had significant differences in age, presence of tinnitus, degree of hearing loss, and triglyceride levels. Spearman's rank correlation analysis showed a negative correlation between hearing threshold of at least 81 dB at 250 to 8000 Hz, the low-density lipoprotein (LDL), triglyceride levels, and the prognosis (r < 0, P < .001). A positive correlation exists between high-density lipoprotein levels and prognosis (r > 0, P < .001). Receiver operating characteristic curve showed LDL level, age, and time since disease onset appears to be highly predictive. Multivariable logistic regression analysis showed that age >47 years, LDL >2.93 mmol/L, and time to presentation >10 days after disease onset are at higher risk for poor prognosis. Conclusion: Factors that influence the prognosis of patients with sudden deafness include age, tinnitus symptoms, high LDL levels, and the type of hearing curve. Early intervention and targeted treatment should be given to high-risk patients to improve the outcome of sudden deafness in clinical practice.

Association of Autonomic Symptom Burden with Sudden Sensorineural Hearing Loss

OBJECTIVE

To investigate the autonomic symptom burden in patients with sudden sensorineural hearing loss (SSNHL) and its association with the severity and prognosis.

STUDY DESIGN

Observational prospective study.

SETTING

Tertiary academic medical center.

METHODS

Patients diagnosed with SSNHL at a single medical center completed the COMPASS 31 questionnaire, which assesses dysautonomia across 6 domains with 31 questions. A total COMPASS 31 score was calculated by summing the scores from each weighted domain. The treatment outcome was evaluated by the percentage of recovery, calculated as the hearing gain in pure tone average (PTA) after treatment divided by the pretreatment PTA difference between the 2 ears. We defined poor recovery as a percentage of recovery <80%.

RESULTS

A total of 63 SSNHL patients were included. The mean COMPASS 31 score was 23.4 (SD 14). Patients with poor recovery had significantly higher COMPASS 31 scores than those with good recovery (mean 26.4 [SD 14.4] vs 16.9 [SD 10.4]; 95% confidence interval [CI] 2-17). There was a negative association between COMPASS 31 score and both hearing gain (r = -.323, 95% CI -0.082 to -0.529) and percentage of recovery (r = -.365, 95% CI -0.129 to -0.562). Multivariate analyses of independent factors indicate that patients with higher COMPASS 31 scores had a greater risk for poor recovery (OR 1.06 [95% CI 1.003-1.117]).

CONCLUSION

This study highlights the association between autonomic symptom burden and poor hearing outcomes in SSNHL patients. The findings underscore the importance of evaluating autonomic function during the treatment of SSNHL.

Approach to Sudden Hearing Loss Among Primary Care Physicians in Riyadh, Saudi Arabia

INTRODUCTION

A medical emergency known as sudden sensorineural hearing loss (SSNHL) affects the ears suddenly, has a considerable probability of negative cognitive and functional outcomes, and can influence the patient's quality of life. Primary care physicians play a crucial role in diagnosing SSNHL and initiating prompt and efficient management since they are the ones who would likely encounter it initially. This study aims to evaluate the present knowledge, diagnostic, and management perspective of SSNHL among primary care physicians in Riyadh, Saudi Arabia.

METHODS

A self-generated questionnaire with 17 questions was developed, and a link to the online survey was delivered to primary care physicians (PHPs) in Riyadh, Saudi Arabia, concerning the management of SSNHL.

RESULTS

The knowledge level regarding SSNHL was evaluated, in which 21 (25%) of the participants had a low knowledge level, 34 (40.5%) had moderate knowledge, and 29 (34.5%) had a high knowledge level. Among 84 participants, 20 (23.8%) were confident in their ability to administer and understand the findings of tuning fork tests (TFT) to differentiate between sensorineural hearing loss and conductive hearing loss, whereas 64 (76.2%) were unsure about it. In addition, to distinguish between sensorineural hearing loss and conductive hearing loss, 62 (73.8%) participants were confident, and 22 (26.2%) participants were skeptical about their ability to interpret a formal audiogram.

CONCLUSION

Considering SSNHL as a medical emergency, in our survey, many family doctors would make proper referral and treatment decisions. However, TFTs were underutilized for guiding management decisions compared to other ways to distinguish between conductive and sensorineural hearing loss.

Machine Learning Models for Predicting Sudden Sensorineural Hearing Loss Outcome: A Systematic Review

BACKGROUND

Machine Learning models have been applied in various healthcare fields, including Audiology, to predict disease outcomes. The prognosis of sudden sensorineural hearing loss is difficult to predict due to the variable course of the disease. Hence, researchers have attempted to utilize ML models to predict the outcome of patients with sudden sensorineural hearing loss. The objectives of this study were to review the performance of these machine learning models and assess their applicability in real-world settings.

METHODS

A systematic search was conducted in PubMed, Web of Science and Scopus. Only studies that built machine learning prediction models were included, and studies that used algorithms such as logistic regression only for the purpose of adjusting for confounding variables were excluded. The risk of bias was assessed using the Prediction model Risk of Bias Assessment Tool (PROBAST).

RESULTS

After screening, a total of 7 papers were eligible for synthesis. In total, these studies built 48 ML models. The most common utilized algorithms were Logistic Regression, Support Vector Machine (SVM) and boosting. The area under the curve of the receiver operating characteristic curve ranged between 0.59 and 0.915. All of the included studies had a high risk of bias; hence there are concerns regarding their applicability.

CONCLUSION

Although these models showed great performance and promising results, future studies are still needed before these models can be applied in a real-world setting. Future studies should employ multiple cohorts, different feature selection methods, and external validation to further validate the models' applicability.

Exploring quality of life post sudden onset hearing loss: A convergent parallel approach

BACKGROUND

 Sudden onset hearing loss (SOHL) is rare and presents differently to individuals; hence, it is complex to diagnose. The impact on the quality of life (QoL) varies for individuals and their support structure. However, the exploration of research designs is warranted.

OBJECTIVES

 This study explored the lived experiences of adults post-SOHL diagnosis and the impact on the QoL. Facilitators of emotional and social aspects of counselling provided by audiologists post-SOHL diagnosis were established.

METHOD

 This was a convergent parallel research study. Data were collected from the two primary participants and three secondary participants, face-to-face and telephonically. The Hearing Handicap Inventory for Adults (HHIA) screening tool and the semi-structured interviews were used for data collection. The data sets were analysed independently, viz. descriptive analysis and thematic analysis, to confirm the impact on the QoL post-SOHL diagnosis.

RESULTS

 The HHIA scores obtained were 84% and 50% for P1 and P2, respectively. Key themes that emerged from the interviews revealed that communication difficulties mostly impacted the QoL, which in turn influenced their mental and social well-being. Aural rehabilitation was perceived as ineffective support, thus the inability to reduce the impact on the QoL post-SOHL diagnosis.

CONCLUSION

 The integrated findings indicated the impact on the QoL post-SOHL diagnosis. Convergent parallel methods should be considered by researchers to understand rare auditory pathologies and their impact on the QoL.Contribution: Person-centred care (PCC) and family-centred care (FCC) are facilitators of counselling that audiologists can employ as QoL management strategies post-SOHL diagnosis.

Sudden Sensorineural Hearing Loss after COVID-19 Vaccination: A Review of the Available Evidence through the Prism of Causality Assessment

Sudden sensorineural hearing loss (SSNHL), a rare audiological condition that accounts for 1% of all cases of sensorineural hearing loss, can cause permanent hearing damage. Soon after the launch of global COVID-19 vaccination campaigns, the World Health Organization released a signal detection about SSNHL cases following administration of various COVID-19 vaccines. Post-marketing studies have been conducted in different countries using either pharmacovigilance or medico-administrative databases to investigate SSNHL as a potential adverse effect of COVID-19 vaccines. Here, we examine the advantages and limitations of each type of post-marketing study available. While pharmacoepidemiological studies highlight the potential association between drug exposure and the event, pharmacovigilance approaches enable causality assessment. The latter objective can only be achieved if an expert evaluation is provided using internationally validated diagnostic criteria. For a rare adverse event such as SSNHL, case information and quantification of hearing loss are mandatory for assessing seriousness, severity, delay onset, differential diagnoses, corrective treatment, recovery, as well as functional sequelae. Appropriate methodology should be adopted depending on whether the target objective is to assess a global or individual risk.

The Importance of Lassa Fever and Its Disease Management in West Africa

Lassa virus (LASV) is a zoonotic pathogen endemic throughout western Africa and is responsible for a human disease known as Lassa fever (LF). Historically, LASV has been emphasized as one of the greatest public health threats in West Africa, with up to 300,000 cases and 5000 associated deaths per year. This, and the fact that the disease has been reported in travelers, has driven a rapid production of various vaccine candidates. Several of these vaccines are currently in clinical development, despite limitations in understanding the immune response to infection. Alarmingly, the host immune response has been implicated in the induction of sensorineural hearing loss in LF survivors, legitimately raising safety questions about any future vaccines as well as efficacy in preventing potential hearing loss. The objective of this article is to revisit the importance and prevalence of LF in West Africa, with focus on Nigeria, and discuss current therapeutic approaches and ongoing vaccine development. In addition, we aim to emphasize the need for more scientific studies relating to LF-associated hearing loss, and to promote critical discussion about potential risks and benefits of vaccinating the population in endemic regions of West Africa.

Increased risk of sudden sensorineural hearing loss in patients with cervical spondylosis

Whether cervical spondylosis (CS) is a risk factor for sudden sensorineural hearing loss (SSNHL) remains unclear. This study used national population-based data to investigate the risk of SSNHL in patients with CS in Taiwan of different ages and sexes. This study used data covering 2 million people in Taiwan, which were obtained from the National Health Insurance Research Database. The data that support the findings of this study are available from National Health Insurance Research Database but restrictions apply to the availability of these data, which were used under license for the current study, and so are not publicly available. Data are however available from the corresponding authors upon reasonable request and with permission of National Health Insurance Research Database. This retrospective cohort study enrolled 91,587 patients with a newly diagnosed CS between January 2000 and December 2018. Case and control cohorts were matched 1:1 according to age, sex, and comorbidities. SSNHL incidence rate and risk were compared between the groups. Cox regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). The mean follow-up period was 8.80 (SD = 4.12) and 8.24 (SD = 4.09) years in the CS and control cohorts, respectively. The incidence rate of SSNHL in the CS cohort (85.28 per 100 000 person-years) was 1.49-fold significantly higher than that in the non-CS cohort (57.13 per 100,000 person-years) (95% CI 1.32-1.68, P < .001). After age, sex, and selected comorbidities were adjusted for, CS exhibited an independent risk factor for SSNHL (adjusted HR = 1.52; 95% CI   1.34-1.71, P < .001). An age-stratified analysis in this study demonstrated a strong and highly significant association between CS and SSNHL in patients aged < 35 years (IRR = 2.28, 95% CI   1.18-4.39, P = .013). This large-scale Taiwanese-population-based retrospective study found that CS was associated with an increased risk of SSNHL. Acute hearing loss in patients with CS, particularly at a young age, should be carefully evaluated, and prompt treatment for SSNHL should be initiated.

Abnormal quantitative sudomotor axon reflex test results in patients with tinnitus as a possible indicator of small fiber neuropathy

A few cases of small fiber neuropathy (SFN) and tinnitus (TN) associated with coronavirus disease 2019 have been reported. However, the relationship between SFN and TN has not been studied. This study investigated a possible relationship between SFN and patients with TN (PwTNs) using autonomic function tests (AFTs) including quantitative sudomotor axon reflex tests (QSART). We performed QSARTs and other AFTs such as the Sympathetic skin response (SSR), Valsalva ratio (VR), and heart rate variability (HRV). The QSART results, obtained at seven hospitals using same protocols, were compared between PwTNs and healthy controls. We confirmed the abnormalities in SSR, VR, and HRV in PwTNs, although those parasympathetic AFTs were not performed in healthy controls. Additionally, we checked Tinnitus handicap inventory (THI) scores for PwTNs and ~50% of PwTNs had low-grade disability, whereas 9.3% had high-grade disability. Data from 57 PwTNs and 122 healthy controls were analyzed. The sweat volumes of QSART in the older age group tended to be higher in the PwTNs than in age-matched healthy controls, and significant differences between the PwTN and control groups were observed in the feet in both sexes (p < 0.001) and in the arms in women (p = 0.013). In the younger age group, the sweat volumes in the feet of men were higher in PwTNs than in healthy controls (p = 0.017). No association was observed between THI and QSART scores. In this study, the sweat volumes in QSARTs were higher in PwTNs than in healthy controls. However, abnormal SSR, HRV, and VR results were not commonly observed in PwTNs. Although the results should be interpreted with caution because of limitations in study, PwTNs might also have SFN apart from dysautonomia. This is the first study to perform QSART with other parasympathetic AFTs in PwTNs. However, larger and more rigorously controlled studies will be needed to reveal the relationship between SFN and TN in the future.

Exploring functional connectivity alterations in sudden sensorineural hearing loss: A multilevel analysis

Sudden sensorineural hearing loss (SSNHL) constitutes an urgent otologic emergency, marked by a rapid decline of at least 30 dB across three consecutive frequencies within 72 h. While previous studies have noted brain region alterations encompassing both auditory and non-auditory areas, this research examines functional connectivity changes across integrity, network, and edge levels in SSNHL. The cohort included 184 participants: 107 SSNHL patients and 77 age- and sex-matched healthy controls. Our investigation comprises: (1) characterization of overall functional connectivity degree across 55 nodes in nine networks (p < 0.05, corrected for false discovery rate), exposing integrity level changes; (2) identification of reduced intranetwork connectivity strength within sensory and attention networks (somatomotor network, auditory network, ventral attention network, dorsal attention network) in SSNHL individuals (p < 0.05, Bonferroni corrected), and reduced internetwork connectivity across twelve distinct subnetwork pairs (p < 0.05, FDR corrected); (3) revelation of increased internetwork connectivity in SSNHL patients, primarily spanning dorsal attention network, fronto parietal network, default mode network, and limbic network, alongside widespread reductions in connectivity patterns among the nine distinct resting-state brain networks. The study further uncovers negative correlations between SSNHL duration and intranetwork connectivity of the auditory network (p < 0.001, R = -0.474), and between Tinnitus Handicap Inventory (THI) scores and internetwork connections linking auditory network and dorsal attention network (p < 0.001, R = -0.331). These observed alterations provide crucial insights into the neural mechanisms underpinning SSNHL and extend our comprehension of the brain's network-level responses to sensory loss. By unveiling the intricate interplay between sensory deprivation, adaptation, and cognitive processes, this study lays the groundwork for future research targeting enhanced diagnosis, treatment, and rehabilitation approaches for individuals afflicted by SSNHL.

Efficacy of high dose systemic versus combined (systemic and intratympanic) corticosteroid therapy in idiopathic sudden sensorineural hearing loss: A prospective randomized trial and risk factor analysis

The pathophysiology and the proper treatment of idiopathic sudden sensorineural hearing loss (ISSNHL) are an ongoing subject of debate. Locally or systemic administered corticosteroids are the most accepted drugs of treatment in reference to ISSNHL (idiopathic sudden sensorineural hearing loss), however, no strong evidence nor guidelines regarding their effectiveness yet exists. In our prospective, randomized, controlled trial 78 participants were enrolled. Patients were randomly assigned based on the day of admission to two groups according to treatment: group SS (n = 43) received intravenous systemic methylprednisolone alone, and group CT (n = 35) received intratympanic dexamethasone + systemic methylprednisolone. The primary outcome was to compare the hearing outcomes between the treatment groups based on different, widely accepted categories (Siegel, Kanzaki, modified Siegel and PTA4 gain). In consideration of the secondary outcome, we examined the effect of the various risk factors on the hearing improvement. No differences were detected regarding hearing improvement between the two groups, based on any criteria [Siegel's criteria (p = 0.604); Kanzaki's criteria (p = 0.720); modified Siegel's criteria (p = 0.524) and PTA 4 gain (p = 0.569)]. However, several clinical factors such as vertigo (p = 0.039), or cardiovascular comorbidity (p = 0.02) and the severity of initial hearing loss (p = 0.033) were found to bear a significant impact upon the hearing outcome. To the best of our knowledge, this is the first randomized controlled trial comparing high dose systemic and combination corticosteroid therapy in ISSNHL patients. Our findings suggest coexisting cardiovascular comorbidity, vertigo and severity of the initial hearing loss may bear a significantly higher impact upon hearing improvement, than the additional intratympanic steroid administration. The presented trial was registered in the European Union Drug Regulating Authorities Clinical Trials Database (name: Combinated systemic and intratympanic steroid therapy in idiopathic sudden sensorineural hearing loss, No.: 2017-000658-20) and with the ethical approval of The National Institute of Pharmacy and Nutrition (OGYÉI) (protocol No.: 7621, on 2017.02.16.).

The Value of Plasma Atherogenic Index in Prognosis of Sudden Hearing Loss

BACKGROUND

The impact of lipid parameters on hearing loss has been extensively studied in the literature. However, there is currently no study investigating the prognostic factor of plasma atherogenic index in patients with sudden hearing loss. This study aimed to evaluate the relationship of plasma atherogenic index in patients with sudden hearing loss.

METHODS

Plasma atherogenic index is calculated using the logarithmic ratio of triglycerides [mg/dL] to high-density lipoprotein cholesterol ([mg/dL]) based on lipid parameters. The patients were divided into tertiles according to their plasma atherogenic index values and the role of plasma atherogenic index on prognosis was investigated among the tertiles. The difference between baseline and control audiometer values for each patient was calculated, and a linear regression analysis was used to determine its statistical significance.

RESULTS

A total of 84 sudden hearing loss patients (57 male: 68%; 27 female: 32%) were included in the study. The mean age of the study participants was 45.3 ± 14.0. There was an inverse relationship between plasma atherogenic index and difference of audiometer values. Linear regression analyses revealed odds ratio and 95% confidence intervals of 0.405 (0.123-1.331) with P=.135 for 500 Hz, 0.371 (0.071-0.990) with P=.048 for 1000 Hz, 0.319 (0.119-0.851) with P=.024 for 2000 Hz and 0.406 (0.161-0.992) with P=.049 for 4000 Hz.

CONCLUSION

To the best of our knowledge, this is the first study to demonstrate that plasma atherogenic index can serve as an indicator of a poor prognosis in the treatment of sudden hearing loss.

Association between air pollution and sudden sensorineural hearing loss (SSHL): A systematic review and meta-analysis

Recent studies have indicated that air pollution (AP) has harmful effects on hearing and ear diseases such as Sudden Sensorineural Hearing Loss (SSHL). The purpose of this study was to evaluate the impact of exposure to AP on SSHL incidence. Valid electronic databases were searched to retrieve studies published until December 1, 2022, using appropriate keywords. The result of the search was 1146 studies, and after screening according to the defined criteria, in total 8 studies were obtained. The risk of bias (ROB) in the studies and their quality were assessed. Finally, the meta-analysis with a significance level of 5% was performed. The findings revealed that the mean level of SO2, CO, NO2, and PM10 in the patient group was more than that of the control group, and p-values were 0.879, 0.144, 0.077, and 0.138, respectively. There was an indirect relation between air pollutants and SSHL, and PM2.5 showed a significant effect (p < 0.05). Given the limited research and the use of different statistical methods, more research is suggested to confirm this association and to determine the mechanisms by which AP exposure may cause SSHL.

Intratympanic Triamcinolone or Dexamethasone in Sudden Sensory Neural Hearing Loss: A Randomized Clinical Trial

Sudden sensorineural hearing loss (SSNHL) is a condition in which a person experiences a rapid loss of hearing, often in one ear. The cause of SSNHL is not always clear, but it is thought to be related to issues with the inner ear, auditory nerve, or other parts of the hearing pathway. Intratympanic injection is a treatment method for SSNHL in which a medication (corticosteroids) is injected directly into the middle ear space through the tympanic membrane. This randomized clinical trial was conducted in two hospitals in Tehran, Iran. Patients with SSNHL were randomized (using the 4-block method) and included in this study. 0.5 cc of dexamethasone or triamcinolone was injected via a 25-gauge spinal needle into the cone of light of tympanic membrane. This procedure was repeated six times. In the present study, the rate of response to treatment was compared in the two groups of triamcinolone and dexamethasone, which showed that in the group where intratympanic injection of dexamethasone was performed, 70.9% of patients responded to treatment (48.4% had a complete response and 22.5% had a partial response), and in the group receiving intratympanic triamcinolone, 72.5% responded to the treatment and improved, 50% showed a complete response and 22.5% showed a partial response, and no significant difference was found in the statistical analysis of the two groups. Also, the comparison of audiometric parameters (SDS and SRT) did not show any significant difference before and after the treatment based on the treatment group, and the treatment response was found in the same group. No significant differences were noted in terms of outcome. Intratympanic dexamethasone injection was associated with a 70.9% response and triamcinolone injection with a 72.5% response.

Association between Serum Vitamin D Levels and Risk of Sudden Sensorineural Hearing Loss: A cross-sectional Study

Background

Sudden sensorineural hearing loss (SSNHL) is an autoimmune diseases of the inner ear which is usually defined by acute onset of hearing loss in one or both ears, of 30 dB or more on at least three contiguous audiometric frequencies within 3 days or less. This study aimed to compare the serum levels of 25-hydroxyvitamin D (VitD) between patients with SSNHL and healthy controls.

Methods

A total of 50 patients with SSNHL and 50 healthy individuals without hearing loss as control group were enrolled in this study. Serum levels of VitD and other related laboratory tests such as calcium (Ca), phosphorus (P), and parathyroid hormone (PTH) were measured and compared between two study groups.

Results

Serum level of VitD was significantly lower in patients suffering from SSNHL compared to the healthy controls (26.55 ± 14.44 vs. 33.51 ± 14.21, P = 0.017, respectively). VitD insufficiency was observed in 70% (n = 35) of the patients with SSNHL as compared to 44% (n = 22) of healthy individuals, demonstrating a significant difference between two study groups. However, no statistically difference was observed for serum levels of Ca, P, and PTH.

Conclusion

This study indicated an increased prevalence of VitD insufficiency in subjects with SSNHL, suggesting a possible association between serum VitD levels and the development of SSNHL. VitD may protect the hearing loss through its antioxidant role.

A Comparative Study Using Vestibular Mapping in Sudden Sensorineural Hearing Loss With and Without Vertigo

OBJECTIVE

To investigate the impairment patterns in peripheral vestibular organs in sudden sensorineural hearing loss (SSNHL) with and without vertigo.

STUDY DESIGN

Retrospective study.

SETTING

Single tertiary medical center.

METHODS

Data from 165 SSNHL patients in a tertiary referral center from January 2017 to December 2022 were retrospectively analyzed. All patients underwent a video head impulse test, vestibular evoked myogenic potential test, and pure-tone audiometry. Hierarchical cluster analysis was performed to investigate vestibular impairment patterns. The prognosis of the hearing was determined using American Academy of Otolaryngology-Head and Neck Surgery recommendations.

RESULTS

After excluding patients with vestibular schwannoma and Meniere's disease, 152 patients were included in this study. A total of 73 of 152 patients were categorized as SSNHL with vertigo (SSNHL_V) and showed an independent merge of the posterior semicircular canal (PSCC) in cluster analysis. A total of 79 of 152 patients were categorized as SSNHL without vertigo (SSNHL_N) and showed an independent merge of saccule in cluster analysis. The PSCC (56.2%) and saccule (20.3%) were the most frequently impaired vestibular organs in SSNHL_V and SSNHL_N, respectively. In terms of prognosis, 106 of 152 patients had partial/no recovery and showed an independent merge of the PSCC in cluster analysis. A total of 46 of 152 patients had a complete recovery and showed an independent merge of the saccule in cluster analysis.

CONCLUSION

A tendency of isolated PSCC dysfunction was seen in SSNHL_V and partial/no recovery. A tendency of isolated saccular dysfunction was seen in SSNHL_N and complete recovery. Different treatments might be needed in SSNHL depending on the presence of vertigo.

Efficacy and safety of Ginkgo biloba extract as an adjuvant in the treatment of Chinese patients with sudden hearing loss: a meta-analysis

CONTEXT

Ginkgo biloba Linn (Ginkgoaceae) [leaves extract (GBE)] is authorized for the treatment of sudden hearing loss (SHL); however, its clinical feasibility in SHL has not been thoroughly investigated.

OBJECTIVE

To evaluate the efficacy and safety of adjuvant GBE in the treatment of SHL.

MATERIALS AND METHODS

We used PubMed, EMBASE, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Wanfang, Chinese Scientific Journal Database, China Biomedical Database for literature research, starting from inception to 30 June 2022. The key terms: Ginkgo biloba extract, Sudden Sensorineural Deafness. This meta-analysis contained randomized controlled trials that compared the safety and efficacy of the combination of GBE and general treatments (GT) with GT alone for SHL. The extracted data were analyzed using Revman5.4 software with risk ratio (RR), 95% confidence intervals (CI) and mean difference (MD).

RESULTS

Our meta-analysis included 27 articles with a total of 2623 patients. The results revealed that the effects of GBE adjuvant therapy was superior than GT (total effective rate: RR = 1.22, 95% CI: 1.18-1.26, p < 0.00001), the pure tone hearing threshold (MD = 12.29, 95% CI: 11.74-12.85, p < 0.00001) and hemorheology indexes (whole blood high shear viscosity: MD = 1.46, 95% CI: 0.47-2.44, p = 0.004) after treatment were significantly improved compared to non-treatment, while there was no significant difference as for hematocrit (red blood cells) (MD = 4.15, 95% CI: -7.15-15.45, p = 0.47).

CONCLUSION

The efficacy of GBE + GT for the treatment of SHL may be more promising than GT alone.

The Role of Fibrinogen, Homocysteine and Metabolic Syndrome's Alterations in Sudden Sensorineural Hearing Loss (SSHL): A Narrative Review

Fibrinogen and homocysteine (HCY) are molecules known to play a role in vascular homeostasis, and their blood levels are often elevated in patients with metabolic syndrome. Recent evidence suggests that sudden sensorineural hearing loss (SSHL) may have a vascular origin. This has led many authors to advocate that fibrinogen, homocysteine, and metabolic syndrome (MetS) may play a direct role in SSHL. The aim of this brief review is to examine the role and influence of these molecules and MetS on the mechanisms of SSHL. Elevated fibrinogen levels have been associated with a worse prognosis in SSHL, possibly due to increased blood viscosity and decreased blood flow. Similarly, HCY has been associated with vascular damage, particularly in hyperhomocysteinemia, although the exact association with SSHL remains controversial. MetS has been demonstrated to function both as a causative factor and as a contributor to poorer recovery in cases of SSHL. However, although some studies suggest a possible role for these biomarkers and MetS in the prognosis and treatment of SSHL, specific therapeutic and preventive strategies based solely on these factors have yet to be developed. Given their potential role in prognosis and treatment and the global epidemic of metabolic syndrome, this issue needs to be analyzed comprehensively. Thus, further quality studies need to be conducted, even though it is difficult to determine the actual impact of MetS on the development of SSHL, as it is a multifactorial disease affecting multiple organs.

Osteopathic Cranial Manipulative Medicine as a Proposed Addition to the Treatment Regimen for Idiopathic Sudden-Onset Unilateral Sensorineural Hearing Loss: A Case Report

Adult sudden-onset unilateral sensorineural hearing loss is primarily idiopathic. There are few treatment options with high success rates, but the literature suggests there is equally moderate success with oral or intratympanic steroids, with some evidence to support the use of acupuncture as a salvage treatment. Here, we present a case of sudden unilateral sensorineural hearing loss with otolaryngology evaluation and audiograms before and after osteopathic manipulative treatment (OMT). Osteopathic cranial manipulative medicine (OCMM) directed at eustachian tube dysfunction elicited findings indicating resolution of symptoms was at least partly due to cranial treatment. This report explains a probable anatomic mechanism contributing to hearing loss and suggests treatment options that should be considered as part of the treatment of idiopathic unilateral hearing loss. Future research opportunities are also proposed.

Bidirectional Association Between Sudden Sensorineural Hearing Loss and Glaucoma: A Cohort Study

OBJECTIVES

To investigate the bidirectional association between sudden sensorineural hearing loss (SSNHL) and open-angle glaucoma (OAG) over a 12-year follow-up period using nationwide, population-based data.

METHODS

The study was conducted using the National Health Information Database of the National Health Insurance Service (NHIS-NHID), which covered 3.5 million individuals from 2008 to 2019. In Study 1, we evaluated the effect of OAG on SSNHL, and in Study 2, we evaluated the effect of SSNHL on OAG. Participants of the control group were enrolled through "greedy nearest-neighbor" 1:1 propensity score matching.

RESULTS

In Study 1, 26,777 people were included in each group. The hazard ratio (HR) for SSNHL of the OAG group was 1.27 (95% confidence interval [CI], 1.15-1.39). In subgroup analysis, there was significant HR value regarding (old age: 1.17, hyperlipidemia: 1.19). In Study 2, 15,433 people were included in each group. The HR for OAG of the SSNHL group was 1.18 (95% CI, 1.07-1.30). In subgroup analysis, the HRs were significant for old age (2.31), hypertension (1.17), diabetes (1.39), and hyperlipidemia (1.26).

CONCLUSION

Over the 12-year follow-up, we found a bidirectional association between SSNHL and OAG, suggesting a shared pathogenesis.

LEVEL OF EVIDENCE

N/A. Laryngoscope, 133:3169-3177, 2023.

Assessment of prognostic biomarkers in sudden sensorineural hearing loss: A systematic review and meta-analysis

Sudden sensorineural hearing loss (SSNHL) is defined as hearing loss of more than 30 dB in less than 72 h. SSNHL is a frequent complaint and an emergency in otolaryngology. Various biomarkers have been used to determine the prognosis of SSNHL. This systematic review and meta-analysis aims to evaluate the relationship between the different biomarkers and the prognosis of SSNHL. We searched English-language literature up to October 2022 in four databases, including PubMed, Google Scholar, Cochrane, and Science Direct. This search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. This study was reported in the International Prospective Register of Systematic Reviews (PROSPERO) database (ID = CRD42022369538). All studies examining the role of neutrophil to lymphocyte ratio (NLR) concluded that higher NLR is associated with a worse prognosis. The results of studies regarding the relationship between platelet to lymphocyte ratio (PLR) and tumor necrosis factor (TNF) are controversial. Other factors shown to be associated with SSNHL include Glycated hemoglobin (HbA1C), blood glucose, iron levels, serum endocan, salusin-beta, and bone turnover biomarkers. This meta-analysis showed that PLR, NLR, and neutrophils were significantly different between recovered and non-recovered patients. PLR, NLR, and neutrophil count are reliable tools to assess the prognosis of patients with SSNHL.

Overcoming barriers: a review on innovations in drug delivery to the middle and inner ear

Despite significant advances in the development of therapeutics for hearing loss, drug delivery to the middle and inner ear remains a challenge. As conventional oral or intravascular administration are ineffective due to poor bioavailability and impermeability of the blood-labyrinth-barrier, localized delivery is becoming a preferable approach for certain drugs. Even then, localized delivery to the ear precludes continual drug delivery due to the invasive and potentially traumatic procedures required to access the middle and inner ear. To address this, the preclinical development of controlled release therapeutics and drug delivery devices have greatly advanced, with some now showing promise clinically. This review will discuss the existing challenges in drug development for treating the most prevalent and damaging hearing disorders, in particular otitis media, perforation of the tympanic membrane, cholesteatoma and sensorineural hearing loss. We will then address novel developments in drug delivery that address these including novel controlled release therapeutics such as hydrogel and nanotechnology and finally, novel device delivery approaches such as microfluidic systems and cochlear prosthesis-mediated delivery. The aim of this review is to investigate how drugs can reach the middle and inner ear more efficiently and how recent innovations could be applied in aiding drug delivery in certain pathologic contexts.

Sudden Sensorineural Hearing Loss in Patient Incidental to Treatment With Hyaluronic Acid Filler

Hyaluronic acid fillers comprise a major component of aesthetic practice with few serious adverse effects. Hearing loss has not been previously associated with hyaluronic acid filler. The authors describe a case in which a patient developed sudden sensorineural hearing loss 1 day after filler injection into the nasolabial folds. Audiogram showed moderately severe sensorineural loss, and MRI revealed no abnormalities. Despite transtympanic steroid injections and hyperbaric oxygen therapy, the hearing loss persists at the time of writing. Although no causal relationships can be drawn from this case alone, this case serves to reinforce the importance of continued vigilance for future occurrences to minimize the potential risk of this serious adverse event.

Level of Evidence 5