Bilateral simultaneous sudden sensorineural hearing loss

Vestibular function assessment in Idiopathic sudden sensorineural hearing loss: a prospective study

PURPOSE

Idiopathic sudden sensorineural hearing loss (ISSHL) can cause acute damage not only to the auditory function, but also to the vestibular function in addition to damage to the hearing function. The aim of this study was to perform vestibular assessment using caloric test and video head impulse test in patients with idiopathic sudden sensorineural hearing loss. In addition, to evaluate the relationship of dizziness with vestibular tests and post-treatment responses of vestibular tests.

METHODS

This is an observational, longitudinal and prospective study, including patients diagnosed with idiopathic sudden sensorineural hearing. Patients were divided into two groups according to the presence of vestibular complaints at presentation: Group 1: Patients with vestibular complaints, Group 2: Patients without vestibular complaints. All subjects underwent pure tone audiometry (PTA) testing, cold caloric test and video head impulse test (vHIT) during their admission and on the 10th day, 3rd month, and 1st year of their follow-up outpatient clinic controls. A unilateral weakness (UW) in the caloric test response was quantified according to the Jongkees formula.

RESULTS

A positive and significant relationship was found between the degree of hearing loss according to the ASHA criteria pre-treatment and the level of improvement created according to Siegel criteria at the 10th day, 3rd month, 1st year after treatment (respectively p = 0.001, p = 0.001, p < 0.001). When both short-term and long-term results were evaluated after treatment, a positive improvement in the degree of hearing loss was observed. A statistically significant difference was observed between Groups 1 and 2 when the pre-treatment, at 10 days, 3 months and 1 year after treatment the caloric test UW value was compared (respectively p = 0.020, p = 0.004, p = 0.004, p = 0.004). A statistically significant difference was observed between Groups 1 and 2 when the pre-treatment, at 10 days, 3 months and 1 year after treatment vHIT lateral canal VOR value was compared (respectively p = 0.000, p = 0.001, p = 0.000, p = 0.004). When both short-term and long-term results were evaluated after treatment, a positive improvement was observed in both caloric test results and lateral vHIT VOR values. Pre-treatment, post-treatment 10th day, 3rd month, 1st year vHIT anterior and posterior canal VOR values were found to be VOR˃0.8 in all patients. No difference was observed in anterior and posterior canal VOR values.

CONCLUSION

Vertigo in patients with ISSHL "as objectively confirmed through caloric testing and vHIT" can be considered a sign of severe cochlear damage. Our study demonstrated a significantly increased risk of vestibular affect in patients with ISSHL, especially in the presence of vertigo. Thus, we conclude that the focus in ISSHL should not only be on the cochlea but also on the vestibular system.

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, 2024.

Red flags alerting a posterior cranial fossa tumor from audiovestibular perspectives - a review

BACKGROUND

There is no comprehensive and up-to-date overview of audiovestibular approach to the posterior fossa tumors in the literature.

OBJECTIVE

This paper reviewed the literature relating to tumors at the posterior cranial fossa to find red flags alerting a posterior fossa lesion from audiovestibular perspectives.

METHODS

This review was developed from articles published in those journals listed on the journal citation reports. Through the PubMed database, Embase, Google Scholar, and Cochrane library, 60 articles were finally obtained based on the PRISMA guidelines for reporting reviews.

RESULTS

The presence of one red flag indicates a positive predictive value of 33% for detecting a posterior fossa lesion. Clinical features, namely, 1) mid-frequency sudden sensorineural hearing loss (SNHL), 2) bilateral sudden SNHL, and 3) rebound nystagmus may indicate a posterior fossa lesion, representing one, two, and three red flags, respectively.

CONCLUSION

Those with 1) mid-frequency sudden SNHL, 2) bilateral sudden SNHL, and 3) rebound nystagmus trigger one, two, and three red flags, respectively, alerting clinicians the possibility of a posterior fossa lesion, which warrant MR imaging to exclude life-threatening or treatable conditions.

SIGNIFICANCE

Patients with posterior fossa tumors may have potential life-threatening outcome.

Case report: Bilateral sudden deafness in acute middle cerebellar peduncle infarction: central or peripheral?

Background

The middle cerebellar peduncle (MCP) is the most common site associated with hearing impairment in acute ischaemic stroke. Narrowing or occlusion of the vertebrobasilar artery due to atherosclerosis is thought to be the main pathogenesis of MCP infarction. Most previous reports of MCP infarction have not been clear whether the patient's hearing impairment is localized to the center or periphery.

Case presentation

We report 44-year-old man with vertigo, tinnitus, and bilateral sudden sensorineural hearing loss (SSNHL) as the first symptoms. Pure Tone Audiogram revealed complete hearing loss in both ears. Acute bilateral MCP infarction was diagnosed by repeated brain magnetic resonance imaging (MRI). The brainstem auditory evoked potential (BAEP) and the electrocochleography were normal. The otoacoustic emissions showed binaural cochlear dysfunctions. After the antiplatelet, lipid-lowering, steroids and hyperbaric oxygen therapy, the pure-tone average (PTA) showed a clear improvement with 67 decibels (dB) on the right and 73 dB on the left at the 3-month follow-up.

Conclusion

Vertebrobasilar diseases due to atherosclerosis should be routinely considered in middle-aged and elderly patients with vascular risk factors and bilateral hearing loss. Bilateral SSNHL can be a prodrome of acute MCP infarction and it can be peripheral. Brain MRI, brain magnetic resonance angiogram (MRA), brain and neck computed tomography angiography (CTA), BAEP, otoacoustic emissions, and Pure Tone Audiogram help to localize and qualify the diagnosis. Bilateral SSNHL localized to the periphery usually improves better and has a good prognosis. Early detection of hearing loss and intervention can help patients recover.

Development and In-Silico and Ex-Vivo Validation of a Software for a Semi-Automated Segmentation of the Round Window Niche to Design a Patient Specific Implant to Treat Inner Ear Disorders

The aim of this study was to develop and validate a semi-automated segmentation approach that identifies the round window niche (RWN) and round window membrane (RWM) for use in the development of patient individualized round window niche implants (RNI) to treat inner ear disorders. Twenty cone beam computed tomography (CBCT) datasets of unilateral temporal bones of patients were included in the study. Defined anatomical landmarks such as the RWM were used to develop a customized 3D Slicer™ plugin for semi-automated segmentation of the RWN. Two otolaryngologists (User 1 and User 2) segmented the datasets manually and semi-automatically using the developed software. Both methods were compared in-silico regarding the resulting RWM area and RWN volume. Finally, the developed software was validated ex-vivo in N = 3 body donor implantation tests with additively manufactured RNI. The independently segmented temporal bones of the different Users showed a strong consistency in the volume of the RWN and the area of the RWM. The volume of the semi-automated RWN segmentations were 48 ± 11% smaller on average than the manual segmentations and the area of the RWM of the semi-automated segmentations was 21 ± 17% smaller on average than the manual segmentation. All additively manufactured implants, based on the semi-automated segmentation method could be implanted successfully in a pressure-tight fit into the RWN. The implants based on the manual segmentations failed to fit into the RWN and this suggests that the larger manual segmentations were over-segmentations. This study presents a semi-automated approach for segmenting the RWN and RWM in temporal bone CBCT scans that is efficient, fast, accurate, and not dependent on trained users. In addition, the manual segmentation, often positioned as the gold-standard, actually failed to pass the implantation validation.

A review of bilateral sudden sensorineural hearing loss in pediatric patients

OBJECTIVE

Bilateral, sudden sensorineural hearing loss (SSNHL) in the pediatric population is a rare phenomenon potentially detrimental to language acquisition and social development. This study comprehensively reviews and analyzes existing literature to determine any correlation or commonality in etiologies, presentations, and management of this condition.

METHODS

PubMed, Cochrane, Scopus, and Web of Science databases were systematically searched for articles related to pediatric SSNHL from 1970 to 2021. Case series, case reports, and cohort studies were included. Data on patient demographics, etiology, diagnostic testing, management, and hearing recovery were collected.

RESULTS

Excluding duplicates, 553 unique titles were identified by established search criteria, of which 342 titles were relevant to pediatric sudden hearing loss. Forty-six papers reported cases of bilateral SSNHL, totaling 145 individual cases. Not included in the analysis were 45 cases documented as non-organic hearing loss. The average age of the total 145 included patients was 8.5 years and 51 were male. Reported etiologies included cytomegalovirus (n = 3), meningitis (n = 13), mumps (n = 5), ototoxin exposure (n = 13), and enlarged vestibular aqueduct (n = 9). Tinnitus (n = 30) was the most reported concurrent symptom, followed by vertigo (n = 21). Systemic steroid therapy was the most common treatment and, when follow up was reported, most patients (51.2%) had complete or partial recovery of hearing.

CONCLUSIONS

This is a comprehensive review of pediatric bilateral SSNHL. Though often idiopathic, etiologies also include infectious, structural, and autoimmune. Treatment largely consists of systemic steroid therapy, with variables rates of recovery. Further studies on intratympanic administration of steroids may guide future treatment.

Characteristics and prognostic analysis of simultaneous bilateral sudden sensorineural hearing loss

Objective

To evaluate the clinical characteristics of simultaneous bilateral sudden sensorineural hearing loss (Si-BSSNHL) as well as its prognostic factors.

Methods

Patients with Si-BSSNHL who were admitted to the Department of Otology Medicine between December 2018 and December 2021 were enrolled in the case group. Propensity score matching (PSM) for sex and age was used to select the control group, which included people who had unilateral sudden sensorineural hearing loss (USSNHL) during the same time period. Hearing recovery, audiological examinations, vestibular function assessments, laboratory tests, and demographic and clinical manifestations were analyzed for intergroup comparisons. Binary logistic regressions were used for both univariate and multivariate analyses of Si-BSSNHL prognostic factors.

Results

Before PSM, the Si-BSSNHL and USSNHL groups differed significantly (p < 0.05) in terms of time from onset to treatment, initial pure-tone average (PTA), final PTA, hearing gain, audiogram curve type, proportion of tinnitus, high-density lipoprotein level, homocysteine level, and effective rate. After PSM, significant differences were also observed in time from onset to treatment, initial PTA, final PTA, hearing gain, total and indirect bilirubin levels, homocysteine level, and effective rate between the two groups (p < 0.05). There was a significant difference in the classification of therapeutic effects between the two groups (p < 0.001). For prognostic analysis, the audiogram curve type was significantly different between the effective group and the ineffective groups of Si-BSSNHL (p = 0.01), in which the sloping type was an independent risk factor for the prognosis of the right ear in Si-SSNHL (95% confidence interval, 0.006-0.549, p = 0.013).

Conclusion

Patients with Si-BSSNHL had mild deafness, elevated total and indirect bilirubin and homocysteine levels, and poorer prognosis than those with USSNHL. Audiogram curve type was linked to the therapeutic effect of Si-BSSNHL, and the sloping type was an independent risk factor for a poor prognosis in the right ear of Si-SSNHL.

Vestibular function assessment in sudden hearing loss

OBJECTIVES

To perform vestibular assessment using cervical and ocular vestibular evoked myogenic potential, video head impulse test and caloric testing in patients with sudden hearing loss. Moreover, to evaluate the correlation of dizziness with vestibular tests and the correlation of vestibular tests with hearing prognosis.

METHODS

This is an observational, longitudinal and prospective study, including participants diagnosed with sudden hearing loss. The participants underwent cervical and ocular vestibular evoked myogenic potential, video head impulse test and caloric testing. The audiometric assessment was performed at the beginning and at the end of the follow-up. A value of p≤0.05 was considered statistically significant.

RESULTS

Seventeen patients were included in the study sample, with a mean age of 45.4±11.1 years. Five participants (29.41%) had dizziness and 15 (88.23%) had tinnitus. All participants underwent vestibular evaluation through cervical and ocular vestibular evoked myogenic potential and video head impulse test, and 13 of them were evaluated through caloric testing. The cervical vestibular evoked myogenic potential was considered altered in five (29.41%) participants, while 11 (64.71%) showed alterations at the ocular vestibular evoked myogenic potential. The video head impulse test and the caloric testing were considered altered in seven (41.18%) and five (38.46%) participants, respectively. There was no statistically significant correlation between the clinical data and the results of vestibular tests or hearing recovery, nor between the results of vestibular tests and hearing recovery.

CONCLUSION

The assessment through vestibular evoked myogenic potential, video head impulse test and caloric testing showed vestibular involvement in some participants. However, it cannot be stated that the results of the vestibular tests are related to the hearing prognosis of sudden hearing loss.

Bilateral Sudden Sensorineural Hearing Loss: A Distinct Phenotype Entity

OBJECTIVE

To investigate the clinical phenotype and hearing prognosis of patients with unilateral and bilateral (simultaneous and nonsimultaneous) sudden sensorineural hearing loss (SSNHL).

STUDY DESIGN

Retrospective cohort.

SETTING

Otology outpatient clinic of a tertiary university hospital.

PATIENTS

Three hundred eighty-five medical records from patients with SSNHL.

MAIN OUTCOME MEASURES

Comparison of demographic, clinical, and audiometric (pretreatment and posttreatment) data of patients with unilateral and bilateral SSNHL.

RESULTS

Our final analysis comprised of 239 medical records of patients with SSNHL. Most patients had unilateral SSNHL (186, 77.82%). We identified a potential underlying cause for the SSNHL in 105 (43.9%) of the cases, being more frequent in cases of bilateral simultaneous SSNHL (100%) as compared with unilateral (45.6%) and nonsimultaneous bilateral SSNHL (22.7%). Cases of simultaneous bilateral SSNHL presented more frequently with severe or profound hearing loss (89%; unilateral SSNHL 50.5%; nonsimultaneous bilateral SSNL, 59.1%) and had a significantly worse hearing recovery prognosis as compared with unilateral or nonsimultaneous bilateral SSNHL (p = 0.002).

CONCLUSION

We observed a high heterogeneity of clinical presentations of SSNHL, the most common being unilateral SSNHL. Our results demonstrate that the clinical and audiological prognosis of simultaneous bilateral SSNHL differed significantly from unilateral and nonsimultaneous bilateral SSNHL, suggesting that simultaneous cases of bilateral SSNHL may be a part of a different disease process. The presence of a simultaneous, bilateral SSNHL indicates the need to investigate the presence of an underlying systemic disease.

Silence is deafening: Acute bilateral hearing loss as a rare presentation of acute stroke

Acute bilateral hearing loss is an uncommon presentation in the Emergency Department (ED), with a variety of potential causes. It is important to consider neurologic vascular etiologies as a cause for acute sensorineural hearing loss. We report a case of acute hemorrhagic stroke presenting as acute bilateral hearing loss. A 60-year-old male with a history of atrial fibrillation presented to the ED with the acute onset of bilateral hearing loss with otherwise intact neurologic testing. He was found to have an acute left temporal hemorrhagic stroke, and magnetic resonance imaging demonstrated multifocal ischemia including an acute right temporal ischemic stroke. In the ED setting, cerebrovascular pathology is an important consideration in the patient presenting with acute hearing loss in the absence of an alternative diagnosis. Missing such a diagnosis can lead to significant morbidity and mortality.

Serum Bilirubin Level as a Potential Marker for the Hearing Outcome in Severe-Profound Bilateral Sudden Deafness

Supplemental Digital Content is available in the text

Objective:

To investigate the association of serum bilirubin level with hearing outcomes in bilateral sudden sensorineural hearing loss (BSSHL) patients.

Participants:

One hundred thirteen in-patient BSSHL patients were consecutively enrolled between July 2008 and December 2015 in a tertiary center.

Main Outcome Measures:

Multivariable linear regression, generalized estimating equations (GEE), and stratified analyses were applied to examine the association between serum bilirubin level and hearing outcome measures such as final hearing threshold and absolute and relative hearing gains in BSSHL.

Results:

After full adjustment for potential confounders, total bilirubin levels (TBIL) were observed to be positively and independently associated with hearing outcomes as measured by final hearing (β [95% confidence interval {CI}]: −1.5 [−2.7, −0.2] dB HL per 1 μmol/L increase in TBIL) and absolute and relative hearing gains (β [95% CI]: 1.4 [0.2, 2.7] dB and 1.6 [0.2, 3.1] dB, respectively) in the severe to profound hearing loss subpopulation.

Conclusions:

Higher TBIL levels, within the normal or mildly elevated ranges, were independently and significantly associated with better hearing outcome in BSSHL patients with severe to profound hearing loss. Given bilirubin elevation treatments exist, our finding suggests a novel pharmacological strategy for this specific subpopulation.

Vestibular evoked myogenic potentials in the prognosis of sudden hearing loss ‒ a systematic review

INTRODUCTION

Sudden hearing loss is an otorhinolaryngological emergency that often leads to severe damage to the auditory and vestibular function. The vestibular evoked myogenic potential is a test that allows a noninvasive evaluation of the otolithic system function and vestibulospinal and vestibulo-ocular pathways.

OBJECTIVE

To evaluate the importance of vestibular evoked myogenic potential in determining the prognosis of patients with sudden hearing loss.

METHODS

A search for articles published up to December 2018 was performed in the PubMed, Cochrane, VHL and LILACS databases using MeSH descriptors. Retrospective and prospective articles were included containing cervical or ocular vestibular evoked myogenic potential in sudden hearing loss patients and information on associated vertigo and/or dizziness.

RESULTS

Sixteen of 62 initially selected articles met the inclusion criteria and were analyzed. Regarding the methodology of the evaluated studies, 8 studies were prospective, six were retrospective, one contained part of the data from a retrospective analysis and another part from a prospective analysis, and one study was cross-sectional. A total of 872 patients were evaluated (50.22% males and 49.77% females) with a mean age of 51.26 years. Four hundred and twenty-six patients (50.35%) had vertigo and/or dizziness associated with sudden hearing loss. The cervical vestibular evoked myogenic potential was performed in all studies, but only seven assessed the ocular vestibular evoked myogenic potential. The cervical vestibular evoked myogenic potential showed alterations in 38.65% of 846 evaluated ears, whereas ocular vestibular evoked myogenic potential showed alterations in 47.88% of 368 evaluated ears. The hearing recovery rate was analyzed by 8 articles, with 63.4% of 410 evaluated ears showing hearing recovery.

CONCLUSIONS

The studies suggest that the assessment of the vestibular system using vestibular evoked myogenic potential seems to be important in the prognosis of sudden hearing loss. For better follow-up of patients with sudden hearing loss, the emphasis should not be limited to the cochlea, but also include the diagnosis and treatment of vestibular abnormalities, regardless of the presence of vertigo.

Comparison between Bilateral and Unilateral Sudden Sensorineural Hearing Loss

Background:

Bilateral sudden sensorineural hearing loss (BSSHL) is rare and assumed to be a different clinical entity compared to unilateral SSHL (USSHL). This study examined the differences between the idiopathic BSSHL and USSHL.

Methods:

Forty-six sequential BSSHL patients (Se-BSSHL) and 68 simultaneous BSSHL (Si-BSSHL) were consecutively admitted between June 2008 and December 2015. Two sets of patients served as control groups: (1) USSHL patients with healthy contralateral ear and (2) USSHL patients with contralateral preexisting hearing loss (USSHLwCHL). We retrospectively analyzed differences among four cohorts using analysis of variance, Kruskal-Wallis test, Welch's t-test, and Chi-square test as appropriate before and after propensity score matching (PSM) based on age, gender, and body mass index (BMI).

Results:

The prevalence of idiopathic BSSHL was 8.6% (114/1329) among the total SSHL patients. In the total cohort, USSHL patients tended to be younger, female, and tended to have lower BMI, renal parameters, and total cholesterol in addition to higher high-density lipoprotein compared to the other three groups. Most routine blood indicators, some coagulation markers, and immunoglobulin M (H = 13.4, P = 0.004) were significantly different among the study groups. After PSM, the major significant differences were found in audiometric characteristics. Si-BSSHL and Se-BSSHL patients demonstrated similar hearing thresholds as USSHL but were significantly better than the USSHLwCHL patients across most frequencies before and after treatment (H = 30.0, P < 0.001 for initial hearing and H = 12.0, P = 0.007 for final hearing). Moreover, the BSSHL patients showed different hearing loss distribution patterns (more descending type, χ² = 33.8, P = 0.001) with less hearing gain (H = 17.5, P < 0.001) compared to the USSHL patients.

Conclusions:

Idiopathic BSSHL is a relatively rare subtype of SSHL with a higher rate of descending audiogram type and inferior hearing outcome rather than being classified as a completely different disease entity compared to USSHL.

Differences in Intrinsic Brain Abnormalities Between Patients With Left- and Right-Sided Long-Term Hearing Impairment

Unilateral hearing impairment is characterized by asymmetric hearing input, which causes bilateral unbalanced auditory afferents and tinnitus of varying degrees. Long-term hearing imbalance can cause functional reorganization in the brain. However, differences between intrinsic functional changes in the brains of patients with left- and those with right-sided long-term hearing impairments are incompletely understood. This study included 67 patients with unilateral hearing impairments (left-sided, 33 patients; right-sided, 34 patients) and 32 healthy controls. All study participants underwent blood oxygenation level dependent resting-state functional magnetic resonance imaging and T1-weighted imaging with three-dimensional fast spoiled gradient-echo sequences. After data preprocessing, fractional amplitude of low frequency (fALFF) and functional connectivity (FC) analyses were used to evaluate differences between patients and healthy controls. When compared with the right-sided hearing impairment group, the left-sided hearing impairment group showed significantly higher fALFF values in the left superior parietal gyrus, right inferior parietal lobule, and right superior frontal gyrus, whereas it showed significantly lower fALFF values in the left Heschl’s gyrus, right supramarginal gyrus, and left superior frontal gyrus. In the left-sided hearing impairment group, paired brain regions with enhanced FC were the left Heschl’s gyrus and right supramarginal gyrus, left Heschl’s gyrus and left superior parietal gyrus, left superior parietal gyrus and right inferior parietal lobule, right inferior parietal lobule and right superior frontal gyrus, and left and right superior frontal gyri. In the left-sided hearing impairment group, the FC of the paired brain regions correlated negatively with the duration and pure tone audiometry were in the left Heschl’s gyrus and right supramarginal gyrus. In the right-sided hearing impairment group, the FC of the paired brain regions correlated negatively with the duration was in the left Heschl’s gyrus and superior parietal gyrus, and with pure tone audiometry was right inferior parietal lobule and superior frontal gyrus. The intrinsic reintegration mechanisms of the brain appeared to differ between patients with left-sided hearing impairment and those with right-sided hearing impairment, and the severity of hearing impairment was associated with differences in functional integration in certain brain regions.

Side-related differences in sudden sensorineural hearing loss in children

OBJECTIVE

Most studies on sudden sensorineural hearing loss (SSNHL) do not differentiate the outcomes within varied affected ears in children. The present study was designed to determine the clinical differences between unilateral and bilateral SSNHL in children.

METHODS

The clinical data, from a total of 101 pediatric patients with SSNHL, was retrospectively analyzed from January 2003 to December 2016. The main outcome measures included basic characteristics, etiology, clinical symptoms and treatment courses.

RESULTS

When the bilateral group (n = 28) was compared to the unilateral group (n = 73), neither gender nor onset of SSNHL was significantly different (p > 0.05 each); However, bilateral SSNHL tended to occur in younger ages (8.1 ± 4.0 yrs), with higher percentages of suspected etiologies (50%) and proportion of profound deafness (55.4%, p < 0.05 each). The short-term recovery rate was superior in the unilateral cases over the bilateral cases (37.0% vs. 12.5%, p < 0.05). Milder initial hearing threshold, early onset of treatment (5.6 ± 4.8 days) with unilateral involvement and an older age (11.3 ± 3.0 yrs) in bilaterally affected cases were associated with a better prognosis in this cohort. In addition, the unilateral group showed comparable outcomes, when sub-analyzed by comparison to that in either left- (n = 42) or right-sided (n = 31) SSNHL.

CONCLUSION

Although bilateral and unilateral pediatric SSNHL could cause partial to complete cochlear lesion, they may be relevant to distinct backgrounds. Our data also provides valuable information about demographics and outcomes of SSNHL in children.