Development of clinical predictive nomograms for prognosis of idiopathic sudden sensorineural hearing loss.

BACKGROUND: The outcome of clinical treatment for idiopathic sudden sensorineural hearing loss (ISSNHL) is frequently the primary concern. AIM: For the convenient prediction of reference prognosis outcomes in patients with ISSNHL. MATERIALS AND METHODS: Patients diagnosed with ISSNHL who were admitted to the otorhinolaryngology ward of Zhejiang Provincial Hospital of Traditional Chinese Medicine from January 2020 to December 2023 were included. Univariate and multivariate logistic regression analyses were employed to identify independent prognostic factors for the treatment outcome of ISSNHL, which were subsequently used to develop nomograms. Discrimination, calibration, and clinical utility were assessed to evaluate the performance of the ISSNHL nomograms. RESULTS: 371 ISSNHL patients were enrolled in this study. Multivariable logistic regression analysis showed that history of deafness, aural fullness, time of onset, and age were independent prognostic factors for ISSNHL patients, with statistically significant regression coefficients. Predictive nomograms were developed with excellent discrimination, calibration, and clinical value. CONCLUSIONS: Leveraging data from ISSNHL patients, we developed a predictive nomogram to assess prognostic factors upon admission. This nomogram facilitates clinicians in approximating the likelihood of favorable prognosis. SIGNIFICANCE: By accumulating clinical data from ISSNHL patients, it's anticipated that the possibility of recovery following treatment can be determined.

Management of Idiopathic Sudden Sensorineural Hearing Loss (ISSNHL) Intratympanic Platelet-Rich Plasma (PRP) Versus Intratympanic Steroid Injections: A Cross-Sectional Study.

<b><br>Introduction:</b> Idiopathic sensorineural hearing loss of 30 decibels (dB) or more over at least three contiguous audiometric frequencies with an onset of less than 3 days is referred to as sudden sensorineural hearing loss (ISSNHL) and is known as an ENT (ear, nose, and throat) emergency. When a patient's hearing suddenly deteriorates, they become confused, anxious, and worried. One of the primary therapies for sudden sensorineural hearing loss is intratympanic steroids. Intratympanic injections of platelet-rich plasma (PRP) improve inner ear hair cells, which enhances hearing.</br> <b><br>Aim:</b> To show the safety and efficacy of intratympanic PRP injection in the management of ISSNHL in comparison with intratympanic steroid injection.</br> <b><br>Methods:</b> The study group was comprised of 100 patients who had experienced ISSNHL within 30 days with no retrocochlear pathology, as demonstrated by a negative MRI scan. 50 patients received 6 intratympanic steroid injections, while the remaining 50 patients received 2 intratympanic injections of PRP at a 1-week interval.</br> <b><br>Results:</b> A total of 39 patients with PRP injection noted an improvement in their hearing of 25 db after 2 weeks and of 30 db after 2 months, with improved speech discrimination of 26% after 2 weeks and of 28% after 2 months. 31 patients with intratympanic steroid injection noted an improvement in their hearing of 18 db after 2 weeks and of 22 db after 2 months, with improved speech discrimination of 21% after 2 weeks and of 24% after 2 months.</br> <b><br>Conclusions:</b> PRP appears safe and efficient for the treatment of ISSNHL, with a low cost and no systemic side effects, as with oral steroids. Therefore, such research should be continued.</br>.

Aberrant Intra- and Inter-Network Connectivity in Idiopathic Sudden Sensorineural Hearing Loss with Tinnitus.

BACKGROUND: Idiopathic Sudden Sensorineural Hearing Loss (ISSNHL) is related to alterations in brain cortical and subcortical structures, and changes in brain functional activities involving multiple networks, which is often accompanied by tinnitus. There have been many in-depth research studies conducted concerning ISSNHL. Despite this, the neurophysiological mechanisms of ISSNHL with tinnitus are still under exploration. OBJECTIVE: The study aimed to investigate the neural mechanism in ISSNHL patients with tinnitus based on the alterations in intra- and inter-network Functional Connectivity (FC) of multiple networks. METHODS: Thirty ISSNHL subjects and 37 healthy subjects underwent resting-state functional Magnetic Resonance Imaging (rs-fMRI). Independent Component Analysis (ICA) was used to identify 8 Resting-state Networks (RSNs). Furthermore, the study used a two-sample t-test to calculate the intra-network FC differences, while calculating Functional Network Connectivity (FNC) to detect the inter-network FC differences. RESULTS: By using the ICA approach, tinnitus patients with ISSNHL were found to have FC changes in the following RSNs: CN, VN, DMN, ECN, SMN, and AUN. In addition, the interconnections of VN-SMN, VN-ECN, and ECN-DAN were weakened. CONCLUSION: The present study has demonstrated changes in FC within and between networks in ISSNHL with tinnitus, providing ideas for further study on the neuropathological mechanism of the disease.

Local vs Systemic Use of Steroids for Sudden Deafness with Diabetes: A Systematic Review and Meta-Analysis.

BACKGROUND: Diabetes is associated with a risk of idiopathic sudden deafness. The main treatment of diabetic sudden deafness is systemic and topical application of steroids. Topical steroid therapy reduces systemic adverse reactions compared with systemic therapy. PURPOSE: The aim of this study was to conduct a meta-analysis design on the improvement value and recovery rate of pure tone mean hearing threshold (PTA).To investigate whether there is difference between local and systemic steroid treatment as the initial treatment for sudden deafness patients with diabetes. METHODS: We searched databases from publication date to October 1, 2022 including PubMed, EMBASE, Cochrane Library, web of science, CNKI, Wan fang Database, China Biomedical Literature Database (CBM), and VIP information resource system. A systematic literature review was conducted on the efficacy and safety of local and systemic steroid therapy for diabetic sudden deafness. RevMan5.4 and stata14 software were used for Meta-analysis. RESULTS: A total of 23 studies were included in this study, covering 1777 patients, including 885 cases in the observation group (local steroid group) and 894 cases in the control group (systemic steroid group). Meta-analysis showed that there was a significant difference in the total effective rate of local and systemic steroid treatment for diabetic sudden deafness between groups (RR = 1.17, 95% CI = 1.11-1.22, P < 0.05). The effective rate in the observation group was higher than that in the control group. For the improvement of PTA, the difference between groups was statistically significant (RR = 6.60, 95% CI = 3.07-10.14, P < 0.05). The improvement of PTA in the local steroid group was higher than that in the systemic steroid group. Subgroup analysis showed that there were significant differences between groups in hormones, drug administration, follow-up time and course of disease. CONCLUSION: Topical steroid therapy is effective in the treatment of diabetic sudden deafness. Hormone methylprednisolone has high effective rate; the shorter the course of disease and the longer the follow-up time are, the higher the total effective rate will be. Tympanic injection is more effective than post-aural injection. Topical steroid injections are safer for hormonal side effect.

The relationship between serum lipid and sudden sensorineural hearing loss.

BACKGROUND: Hyperlipidemia may be part of the important mechanisms for the development of idiopathic sudden sensorineural hearing loss (ISSNHL). AIMS: So the purpose of this study was to evaluate the relationship between changes in blood lipid levels and ISSNHL. MATERIALS AND METHODS: We enrolled 90 ISSNHL patients in our hospital using a retrospective study design from 2019.1 to 2021.12. Blood levels of total cholesterol (TC), triglycerides (TG), and low-density lipoprotein (LDL-C). Hearing recovery was analyzed using the chi-square test and one-way analysis of variance (ANONA). Univariate and multifactorial Logstic retrospective analyses to establish the relationship between LDL-C/HDL-C ratio and hearing recovery after adjustment for potential confounding factors. RESULTS: In our study, 65 (72.2%) patients had their hearing recovered. All group analyses and three group analyses (i.e. Excluding the no-recovery group) found that LDL/HDL was on an upward trend from complete recovery to a slight recovery group and strongly associated with hearing recovery. Univariate and multivariate logistic regression analysis found high levels of LDL and LDL/HDL in the partial hearing recovery group, relative to the full hearing recovery group. Curve fitting intuitively demonstrates the influence of blood lipids on prognosis. CONCLUSIONS: Our findings suggest that LDL. TC, TC/HDL, and LDL/HDL concentrations may be closely related to the pathogenesis of ISSNHL. SIGNIFICANCE: Improving the relevant lipid test at the time of admission to the hospital has good clinical significance for improving the prognosis of ISSNHL.

Vascular loops in cerebellopontine angle in patients with unilateral idiopathic sudden sensorineural hearing loss: Evaluations by three radiological grading systems.

Objective: We aimed to investigate the impact of the position, configuration and neurovascular contact of the anterior inferior cerebellar artery (AICA) in cerebellopontine angle (CPA) and internal auditory canal (IAC) on the clinical features of patients with unilateral idiopathic sudden sensorineural hearing loss (ISSNHL). Methods: One hundred and thirty-six patients with unilateral ISSNHL were enrolled. All patients received detailed history inquiry and standard treatments. Pure tone audiometry and magnetic resonance imaging (MRI) of CPA-IAC were performed. The MRI findings of both ears were evaluated by the Chavda, Gorrie and Kazawa systems. The association between radiological findings and clinical data were analyzed. Results: (1) No significant interaural difference in the position, configuration and neurovascular contact of AICA was observed. (2) There was no significant association between the AICA loop and concomitant vertigo or pre-treatment audiometric configuration in the affected ear. (3) Concomitant tinnitus seemed to be affected by the configuration of AICA categorized by Kazawa system, while the Chavda and Gorrie classification of AICA loop was unassociated with tinnitus. (4) Hearing outcomes were not compromised by the position or configuration of AICA based on the Chavda and Kazawa systems. Patients with Gorrie type B tended to have better hearing recovery than those with type C. Conclusions: In patients with ISSNHL, the position, configuration and neurovascular contact of AICA in the CPA-IAC were unassociated with the side of hearing loss, audiometric configurations, or concomitant vertigo. The neurovascular contact graded by Gorrie system might be associated with hearing outcomes.

Video Head Impulse Test Findings in Patients With Benign Paroxysmal Positional Vertigo Secondary to Idiopathic Sudden Sensorineural Hearing Loss.

Benign paroxysmal positional vertigo (BPPV) is amongst the most common causes of episodic vestibular syndrome. It can be classified as idiopathic and secondary types according to the causative factors, and the underlying mechanism between idiopathic (i-BPPV) and secondary BPPV (s-BPPV) may differ. Idiopathic sudden sensorineural hearing loss (ISSNHL) has been considered as a common inner ear disease that precipitates s-BPPV. Yet, few studies have addressed the functional impairment of the semicircular canal (SCC) system in patients with s-BPPV associated with ISSNHL. Our purpose was to explore the pathophysiological mechanism and investigate the clinical implications of video head impulse test (vHIT) in these patients. Here, the clinical and laboratory data of patients with BPPV secondary to ISSNHL, including the results of vHIT, were retrospectively reviewed, and compared with those of patients with i-BPPV. Pathological vHIT findings (low vestibulo-ocular reflex gain and re-fixation saccade), which mainly affected the posterior SCC, were more common in the s-BPPV group than in the i-BPPV group (41.9 and 0%, respectively). The incidence of horizontal SCC involvement was also higher in the s-BPPV group (45.16 and 16.67%, respectively). Furthermore, patients with s-BPPV showed lower vHIT gains of the posterior and horizontal SCCs in affected ears than in unaffected ears. Compared to i-BPPV, posterior SCC paresis detected by vHIT is more prevalent in BPPV secondary to ISSNHL. This dysfunction may be associated mainly with vestibular impairments caused by ISSNHL, and not with BPPV per se.

Intratympanic corticosteroid as salvage therapy in treatment of idiopathic sudden sensorineural hearing loss: A systematic review and meta-analysis.

BACKGROUND: The standard treatment of idiopathic sudden sensorineural hearing loss (ISSNHL) constitutes of systemic oral corticosteroid. Although oral corticosteroid might revert the acute deafness, some patients with ISSNHL display a more treatment refractory course. For these patients, corticosteroid installed directly into the middle ear has become a more frequent treatment, due to the potential benefits of a high, local concentration compared to a systemic administration. As such, for patients being refractory to standard treatment, intratympanic injection of a high dosage of corticosteroid as salvage therapy may be beneficial. OBJECTIVES: To evaluate the efficacy of intratympanic corticosteroid (ITC) as a salvage treatment of ISSNHL. METHODS: A systematic literature search was performed in relevant databases. Both randomized trials and observational studies were considered for inclusion. The risk of bias was evaluated using the Cochrane risk of bias tool (randomized trials) or ROBINS-I tool (observational studies). Meta-analysis was performed to investigate the improvement of PTA (dB) and number of patients displaying recovery following salvage ITC injections. Occurrence of serious side effects was investigated. Finally, the certainty of the evidence was evaluated using the GRADE approach. RESULTS: Eleven relevant studies were identified (4 randomized trials and 7 observational studies). Both observational and randomized trials showed that salvage ITC significantly increased the number of patients displaying recovery. No serious adverse events were identified in any of the included studies. The certainty of evidence ranged from moderate to very low, due to risk of bias, imprecision, and heterogeneity. CONCLUSION: Collectively, our findings indicate that salvage ITC treatment may be a beneficial and safe treatment for patients with sudden hearing loss, who otherwise are refractory to standard treatment approaches. However, the evidence level indicates need for a cautious interpretation of especially the magnitude of effect and thus the extrapolation on how much the individual may improve from this treatment. Furthermore, it remains to be investigated whether treatment outcomes may vary across different patient groups presenting with ISSNHL. This potential variation in treatment response should be kept in mind, when counselling the patient. TRIAL REGISTRATION NUMBER: The protocol is registered in PROSPERO. Registration number: CRD42019130586.

Clinical Value of 3D-FLAIR MRI in Idiopathic Sudden Sensorineural Hearing Loss.

BACKGROUND: Three-dimensional fluid-attenuated inversion recovery sequence magnetic resonance imaging (3D-FLAIR MRI) has been used in the diagnosis of inner ear diseases. However, the relevance of 3D-FLAIR MRI appearances with multiple features and prognosis of patients with idiopathic sudden sensorineural hearing loss (ISSNHL) remains unclear. METHODS: This study was a retrospective trial. We recruited 1300 patients with unilateral ISSNHL hospitalized from May 2017 to January 2019. They were divided into four groups according to their 3D-FLAIR MRI appearances: normal (n = 739), inner ear hemorrhage (n = 218), increased protein content (n = 288), and blood-labyrinth barrier damage (n = 55). The correlation between 3D-FLAIR MRI appearances and the degree or type of deafness of the participants was analyzed. RESULTS: There was a statistical difference in the deafness side (p < 0.001) and vestibular dysfunction (p < 0.001) among the four groups. There was a statistical difference in the duration of treatment (p < 0.001) and the incidence of dizziness or vertigo (p < 0.001) for patients among these groups. The degree of deafness in the patients in the inner ear hemorrhage group was significantly more severe than that of the patients in the other three groups (p < 0.001). CONCLUSION: 3D-FLAIR MRI appearances were correlated with the prognosis of patients with ISSNHL.

Usefulness of stress-related hormones as predictors and prognostic factors for idiopathic sudden sensorineural hearing loss.

BACKGROUND: The pathogenesis of Idiopathic sudden sensorineural hearing loss (ISSNHL) is ambiguous. Stress is commonly defined as a cause of the disease. Serum levels of stress-related hormone (cortisol, growth hormone, aldosterone, ADH, ACTH) may be elevated in patients with ISSNHL patients. OBJECTIVES: We aimed to determine whether psychological factors and stress hormones in patients are associated with the severity of hearing loss and therapeutic outcomes. We hypothesized that the stress hormone level in the disease sequence is a strong prognostic factor of ISSNHL. Additionally, we investigated whether the subjective degree of psychological stress is likely to contribute to the therapeutic prognosis of ISSNHL, as determined using questionnaires. METHODS: We conducted a prospective study of patients aged between 19 and 65 years admitted for the treatment of ISSNHL at our hospital. All patients underwent pure tone audiometry (PTA) on day 0, day 5 and 2 weeks after discharge. As an objective indicator of stress, we measured the level of HPA axis-related hormones. So, we measured serum cortisol, adrenocorticotropic hormone (ACTH), aldosterone and dehydroepiandrosterone sulfate (DHEAS) levels in the venous blood sample of patients on day 1 and day 5 after admission. In addition, for subjective stress measurements, depression and anxiety levels were assessed using self-reported questionnaires, Beck Depression Inventory (BDI), and Perceived Stress Scale (PSS) in the revised to Korean versions. RESULTS: Eighteen patients diagnosed with ISSNHL at the Department of Otorhino-laryngology were enrolled. Serum DHEAS level measured on day 1 showed a statistically significant correlation with the hearing threshold in the hearing test performed at the time of diagnosis (p = .037, correlation coefficients(r) = 0.541). Serum ACTH level was measured on day 1, and patients were classified into normal and elevated groups based on a threshold of 1.5 pg/mL; the normal group had better hearing thresholds in the first and second hearing test than the elevated group (p = .040, 0.015, respectively). In the stress-related questionnaires, the BDI score showed a statistically significant correlation with the last hearing test (p = .015, correlation coefficients(r) = 0.613). CONCLUSION: We demonstrated the possible role of stress-related hormones in the pathogenesis of ISSNHL and suggest that depressive stress response can be a strong predictor of treatment response in patients with ISSNHL. However, the impact of response to stress on the inner ear and endolymph homeostasis remains unknown. Since this is a cross-sectional study, we can only comment on the relationship between stress and ISSNHL, not a causal relationship. Further investigation is necessary to identify the mechanism of interaction between stress and hearing ability in the inner ear.

Correlation between serum lipid and prognosis of idiopathic sudden sensorineural hearing loss: a prospective cohort study.

BACKGROUND: To investigate the correlation between blood lipids and the prognosis of idiopathic sudden sensorineural hearing loss (ISSNHL). METHODS: We included 232 patients with ISSNHL at the Second Affiliated Hospital of Shanghai University from June 2015 to March 2017 using a prospective cohort study design. We collected information including age, gender, hypertension, diabetes, mellitus, vertigo, as well as the levels of blood total cholesterol (TC), triglycerides (TG), and low-density lipoproteins (LDL-C). We also recorded the ratio between the levels of low-density lipoproteins and the levels of high-density lipoproteins (LDL-C/HDL-C ratio). Correlations between the prognosis of ISSNHL and TC, TG, LDL-C, and LDL-C/HDL-C ratio were analyzed by univariable and multivariable logistic regression analyses. RESULTS: The clinical effectiveness rate of patients with TC ranging from 5.2 to 6.2 mmol/L was significantly higher than that of patients with TC <5.2 mmol/L (P<0.001). No notable difference was found between patients with TC <5.2 mmol/L and patients with TC ≥6.2 mmol/L. The clinical effectiveness rate of patients in TG ranging from 1.7 mmol/L to 2.3 mmol/L was markedly higher than those in TG <1.7 mmol/L (P<0.001). No significant difference was found between patients with TG ranging from 2.3 to 5.6 mmol/L, TG ≥5.6 mmol/L, and TG <1.7 mmol/L. The clinical effectiveness rate of patients in LDL-C/HDL-C <1.5 was considerably higher than those in LDL-C/HDL-C ranging from 1.5 to 2.5, 2.5 to 3.5, and ≥3.5 (P<0.001). CONCLUSIONS: Our findings indicated that TC, TG, and the LDL-C/HDL-C ratio are strongly associated with the prognosis of ISSNHL. These three indices could be recommended as independent markers to predict outcomes.

Inhibition of Brain Area and Functional Connectivity in Idiopathic Sudden Sensorineural Hearing Loss With Tinnitus, Based on Resting-State EEG.

This study aimed to identify the mechanism behind idiopathic sudden sensorineural hearing loss (ISSNHL) in patients with tinnitus by investigating aberrant activity in areas of the brain and functional connectivity. High-density electroencephalography (EEG) was used to investigate central nervous changes in 25 ISSNHL subjects and 27 healthy controls. ISSNHL subjects had significantly reduced activity in the left frontal lobe at the alpha 2 frequency band compared with controls. Linear lagged connectivity and lagged coherence analysis showed significantly reduced functional connectivity between the temporal gyrus and supramarginal gyrus at the gamma 2 frequency band in the ISSNHL group. Additionally, a significantly reduced functional connectivity was found between the central cingulate gyrus and frontal lobe under lagged phase synchronization analysis. These results strongly indicate inhibition of brain area activity and change in functional connectivity in ISSNHL with tinnitus patients.

Steady-state auditory evoked fields reflect long-term effects of repetitive transcranial magnetic stimulation in tinnitus.

OBJECTIVES: Evidence of plastic changes in tinnitus has been demonstrated in functional brain imaging. Although repetitive transcranial magnetic stimulation (rTMS) has been shown to decrease steady-state auditory evoked fields (SSAEFs) in tinnitus, the long-term consequence remained unknown. In addition, association between plastic changes as reflected by hemispheric asymmetry and tinnitus handicap inventory (THI) before and after rTMS have not been addressed. METHODS: Twelve tinnitus patients received rTMS and 12 received sham stimulation. Another 12 healthy participants served as the normal hearing controls. Patients responded to the THI before the 1st session and at one month after the final session of rTMS/sham stimulation. Changes in brain activity were assessed by measuring SSAEFs. RESULTS: SSAEFs remained decreased one month after rTMS compared to before treatment, along with a significant reduction in THI score. There was no significant effect between the index of hemispheric asymmetry and THI score. CONCLUSIONS: The current study objectively demonstrated the long-term effects of rTMS on tinnitus using SSAEFs. A longitudinal study to develop an index using SSAEFs to assess the subjective severity of tinnitus is warranted. SIGNIFICANCE: This study suggests the possible use of SSAEFs to assess the long-term effects of rTMS on tinnitus.

Altered Resting-State EEG Microstate in Idiopathic Sudden Sensorineural Hearing Loss Patients With Tinnitus.

In order to clarify the central reorganization in acute period of hearing loss, this study explored the aberrant dynamics of electroencephalogram (EEG) microstates and the correlations with the features of idiopathic sudden sensorineural hearing loss (ISSNHL) and tinnitus. We used high-density EEG with 128 channels to investigate alterations in microstate parameters between 25 ISSNHL patients with tinnitus and 27 healthy subjects. This study also explored the associations between microstate characteristics and tinnitus features. Microstates were clustered into four categories. There was a reduced presence of microstate A in amplitude, coverage, lifespan, frequency and an increased presence of microstate B in frequency in ISSNHL patients with tinnitus. According to the syntax analysis, a reduced transition from microstate C to microstate A and an increased transition from microstate C to microstate B were found in ISSNHL subjects. In addition, the significant negative correlations were found between Tinnitus Handicap Inventory (THI) scores and frequency of microstate A as well as between THI scores and the probability of transition from microstate D to microstate A. While THI was positively correlated with the transition probability from microstate D to microstate B. To sum up, the significant differences in the characteristics of resting-state EEG microstates were found between ISSNHL subjects with tinnitus and healthy controls. This study suggests that the alterations of central neural networks occur in acute stage of hearing loss and tinnitus. And EEG microstate may be considered as a useful tool to study the whole brain network in ISSNHL patients.

Acupuncture as an early treatment for idiopathic sudden sensorineural hearing loss (ISSNHL) patients with flat or high-frequency drop audiograms: study protocol for a randomized controlled trial.

BACKGROUND: Idiopathic sudden sensorineural hearing loss (ISSNHL) is a common form of deafness. Acupuncture has been used as a salvage therapy for ISSNHL in China since 200 BCE. However, the efficacy of acupuncture has not been confirmed in strictly controlled trials. We designed a randomized controlled clinical trial to evaluate the efficacy and long-term effects of acupuncture in patients with early ISSNHL. METHODS/DESIGN: In this randomized controlled clinical trial, we will enroll 124 participants with ISSNHL diagnosed 2 to 4 weeks prior to enrollment, who have shown little hearing improvement after routine Western medical treatment (i.e., corticosteroids). 62 of these participants will have flat audiogram and the other 62 will have a high-frequency drop audiogram; they will all take Methycobal while half of the flat type and half of the high-frequency drop type will also receive acupuncture treatments for 4 weeks in a four-group design. The primary outcome measure will be the effective rate of hearing improvement (defined as the proportion of patients with at least 15-dB improvement in the hearing loss frequency band). The secondary outcome will measure the improvements in Pure Tone Average, Word Recognition Score, and Tinnitus Handicap Inventory. The assessments of the participants will be made at baseline, after treatment (week 4), and at follow-up (week 28). DISCUSSION: This study aims to explore the efficacy and long-term effects of acupuncture in patients with ISSNHL. This study will be a randomized controlled trial with strict methodology and few design deficits. If our study yields positive results, acupuncture could be recommended as a salvage therapy for patients with ISSNHL. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR-ICR-15006787 . Registered on 12 July 2015.

Hyperbaric Oxygen Treatments Attenuate the Neutrophil-to-Lymphocyte Ratio in Patients with Idiopathic Sudden Sensorineural Hearing Loss.

OBJECTIVE: Hyperbaric oxygen therapy (HBOT) is a promising treatment in the management of idiopathic sudden sensorineural hearing loss (ISSNHL), but the specific mechanisms of HBOT in ISSNHL are still unclear. The curative effects of HBOT in many diseases are related to the attenuation of inflammatory response. The neutrophil-to-lymphocyte ratio (NLR) is a new inflammatory marker that can be assessed quickly. We investigated the relationship between HBOT and the inflammatory response in ISSNHL using the NLR. STUDY DESIGN: Case series with chart review SETTING: Tertiary teaching and research hospital SUBJECTS AND METHODS: Between December 2007 and December 2013, 41 ISSNHL patients who underwent HBOT, 45 ISSNHL patients who did not undergo HBOT, and 14 healthy control subjects who underwent HBOT were included in the study. NLRs were assessed at 2 time points: at baseline (pretreatment) and on day 1 after 10 sessions of HBOT (posttreatment). Audiometric testing was performed at the above 2 time points. RESULTS: The mean post-HBOT NLRs, neutrophil, and white blood cell count values of the ISSNHL patients were significantly lower than their pretreatment values (P < .001). Compared with the ISSNHL patients who did not undergo HBOT, the posttreatment NLR levels of the ISSNHL patients who underwent HBOT were much lower (P = .036). Higher relative hearing gains were significantly associated with a greater reduction in the NLR after HBOT (r = -0.885, P = .001). CONCLUSIONS: The beneficial effect of HBOT on ISSNHL may be mediated at least in part by a decrease of inflammation.