High Frequency Hearing Research Articles

Audiovestibular Manifestations in Autoimmune Disorders: A Case Clinical Control Study in Celiac Patients

Objective: The aim of this study was to evaluate audiovestibulopathy in patients with celiac disease using vestibular evoked myogenic potentials (VEMP), video head impulse test (vHIT), and audiometric examinations. Material and Methods: Thirty-one patients with celiac disease from the gastroenterology department of Cerrahpasa Medical School, and 30 healthy controls were included in the study between 2013 and 2015. Pure tone audiometry, tympanometry, acoustic reflex test, and vestibular evaluation with VEMP and vHIT were performed in both groups. The anti-tissue transglutaminase IgA levels of all participants and disease duration of affected individuals were documented. Results: The mean age±SD was 35.9±12.82 (27-48) years and 37.6±11.6 (26-48) years for the patient and control groups, respectively. The pure tone thresholds did not differ between the two groups. However, a subgroup of patients with high antibody levels had significantly higher highfrequency hearing thresholds. The two groups had similar VEMP test results, but a comparison of the vestibuloocular reflex (VOR) gains of six semicircular canals (SSC) revealed significant decreases in the right anterior canal in the patient group. Conclusion: Subclinical audiovestibular pathologies can occur in patients with celiac disease. Following these patients with periodic audiovestibular test batteries may reduce patient morbidity by providing early diagnosis and rehabilitation.

The natural history of OTOF-related auditory neuropathy spectrum disorders: a multicenter study.

Pathogenic variations in the OTOF gene are a common cause of hearing loss. To refine the natural history and genotype-phenotype correlations of OTOF-related auditory neuropathy spectrum disorders (ANSD), audiograms and distortion product otoacoustic emissions (DPOAEs) were collected from a diverse cohort of individuals diagnosed with OTOF-related ANSD by comprehensive genetic testing and also reported in the literature. Comparative analysis was undertaken to define genotype-phenotype relationships using a Monte Carlo algorithm. 67 audiograms and 25 DPOAEs from 49 unique individuals positive for OTOF-related ANSD were collected. 51 unique OTOF pathogenic variants were identified of which 21 were missense and 30 were loss of function (LoF; nonsense, splice-site, copy number variants, and indels). There was a statistically significant difference in low, middle, and high frequency hearing thresholds between missense/missense and LoF/missense genotypes as compared to LoF/LoF genotypes (average hearing threshold for low, middle and high frequencies 70.9, 76.0, and 73.4 dB vs 88.5, 95.6, and 94.7 dB) via Tukey's test with age as a co-variate (P = 0.0180, 0.0327, and 0.0347, respectively). Hearing declined during adolescence with missense/missense and LoF/missense genotypes, with an annual mid-frequency threshold deterioration of 0.87 dB/year and 1.87 dB/year, respectively. 8.5% of frequencies measured via DPOAE were lost per year in individuals with serial tests. Audioprofiling of OTOF-related ANSD suggests significantly worse hearing with LoF/LoF genotypes. The unique pattern of variably progressive OTOF-related autosomal recessive ANSD may be amenable to gene therapy in selected clinical scenarios.

Investigation of occupational noise exposure and hearing loss among automobile manufacturing workers

Objective: To investigation the situation of occupational noise exposure and hearing loss among workers in automobile manufacturing enterprise during 2017-2019 in Wuhan. Methods: Workers in automobile manufacturing who underwent physical examination in Wuhan Hospital for the Prevention and Treatment of Occupational Diseases from 2017 to 2019 were included as subjects in the cross-sectional survey. Questionnaire survey, noise detection and pure tone threshold test were used. Excluding individuals with working time less than 3 years and information deficiency, 3 948 individuals were finally included in the study. Results: Among 3 948 workers, 128 workers had hearing loss and the rate of hearing loss was 3.24%, among which 101 workers had high-frequency hearing loss and 27 workers were diagnosed as occupational noise deafness. The prevalence of hearing loss among workers previously exposed to noise was significantly higher than that without prior exposure (12.10%, 0.96%, P<0.05) . The prevalence of hearing loss among workers with occupational noise exposure <80 dB (A) , 80~<85 dB (A) and ≥85 dB (A) was 1.83%, 2.69% and 5.09%, respectively. The prevalence of high frequency hearing loss was 1.60%, 2.05% and 3.71%, respectively. The prevalence of occupational noise deafness was 0.23%, 0.64% and 1.38%, respectively. The prevalence of hearing loss and high frequency hearing loss among workers exposed to different occupational noise was statistically significant (P<0.05) , while the prevalence of occupational noise deafness was not statistically significant (P>0.05) . There were statistically significant differences in the prevalence of hearing loss (2.88%, 4.45%) and occupational noise deafness (0.46%, 1.41%) between those who used protective equipment and those who did not (P<0.05) . Compared with workers exposed to occupational noise <80 dB (A) , workers exposed to occupational noise ≥85 dB (A) had A 3.16-fold increased risk of hearing loss (OR=3.16, 95%CI: 1.44~6.95, P<0.05) . Compared to workers using hearing protective equipment, the risk of hearing loss (OR=1.96, 95%CI: 1.25~3.06, P<0.05) and occupational noise deafness (OR=3.46, 95%CI: 1.51-7.96, P<0.05) significantly increased among those without using hearing protective equipment. Conclusion: The risk of hearing loss in automobile manufacturing workers is significantly associated with occupational noise exposure and the use of hearing protective equipment. Good hearing protection may reduce the risk of occupational noise-induced hearing loss and occupational noise deafness.

INTERMITTENT TINNITUS IN ADULTS: AN INSIGHT INTO COVERT HEARING LOSS

Objectives: Association of high frequency hearing loss/minor damage in peripheral auditory system in continuous chronic tinnitus with normal PTA is well established.The purpose of the study was to verify whether this finding is true for intermittent unilateral or bilateral tinnitus patients with normal PTA using EHF audiometry and conventional DPOAEs. Materials and method:This study was conducted on 45 normal hearing adults between the age ranges of 18-30 years. Among them 30 adults comprised of study group with intermittent tinnitus which varies in laterality.Tinnitus evaluation was done on these population followed by THI administration. DPOAE and EHF audiometry was completed on all subjects after conventional hearing assessment program. Result and Discussion:Kruskal Wallis H test &amp; Wilcoxon signed rank test was used to compare OAE amplitude &amp; EHF thresholds.Spearman's correlation was used to evaluate the correlation between DPOAE amplitude with EHF threshold. Reduced hearing sensitivity in the extended high frequency region may be early predictor of outer hair cell dysfunction in the most basal area.Findings of this study suggest that intermittent tinnitus may also lead to subtle lesion at the basal region of cochlea which would result in a significant hearing loss with continuous tinnitus in future. Conclusion:Intermittent tinnitus may increase the fragility of peripheral auditory system which may lead to permanent lesions and would be evident as elevated thresholds in conventional PTA.

High Frequency Hearing Loss in Chronic Renal Disease: A Cross-Sectional Study.

Introduction Chronic kidney disease (CKD) patients face multiple complications. One of them is involvement of the auditory system and it deserves more attention than is paid by the current approaches as hearing loss has major repercussions on the quality of life. Early detection can prevent further deterioration of hearing and improve the quality of life of patients suffering from CKD. Material and methods The high frequency (8-18kHz) audiometry with pure tones was performed in 82 patients with CKD and compared with age and sexes matched healthy control group of 90 patients. Individual ear were used for statistical calculations. Results This study clearly observed that the hearing thresholds for frequencies 8-18kHz increased in CKD patients when compared to sex and aged matched healthy control group, the thresholds significantly increased in CKD with diabetes mellitus as compared to nondiabetic with CKD. The high frequency thresholds significantly increased in patients on hemodialysis, and were significantly correlated with age, stage of CKD and duration of CKD. Conclusion This study highlights the presence of high frequency (8-18kHz) hearing loss in patients of CKD. The severity is significantly correlated with age, stage and duration of CKD.

High frequency hearing impairment and cardiovascular disease in Canada: Results from the Canadian Health Measures Survey.

Noise-induced stress may precipitate cardiovascular diseases. This research assessed the association between sensorineural bilateral high frequency hearing loss (HFHL), as an indication of excessive noise exposure, and cardiovascular outcomes. Participants (n = 6318, ∼50% male) 20-79 years were recruited through the cross-sectional Canadian Health Measures Survey. Questionnaires included several demographic and health-related variables. Audiometry and blood/urine collection took place in a mobile examination centre. Average thresholds ≥25 dB averaged across 3, 4, and 6 kHz defined HFHL. Logistic or linear regression models explored associations between HFHL and cardiovascular-related risk factors/outcomes. Adjusted models indicated elevated diastolic blood pressure in respondents with normal hearing, X¯ = 72.52 (95% confidence interval: 71.85-73.18) compared to the group with bilateral HFHL, X¯ = 70.28 (95%CI: 69.13-71.43), p < 0.05. Average total cholesterol, high-density lipoprotein, low-density lipoprotein and apolipoprotein A1 were elevated in the normal hearing group (p < 0.05). Insulin, high-sensitivity C-reactive protein, and average resting heart rate were elevated in the group with bilateral HFHL, p < 0.05. A stratified analysis by sex- and age, or history of loud occupational noise exposure, did not change the overall results. Although some findings warrant further exploration, the overall analysis did not provide compelling evidence for an association between HFHL and cardiovascular-related biomarkers, or cardiovascular diseases among Canadians aged 20-79 years.

AN OBSERVATIONAL STUDY OF HEARING THRESHOLDS IN PROFESSIONAL DRIVERS

Introduction: Noise has become a very important stress factor in the environment. Drivers are the most commonly affected persons due to trafc noise. The majority of drivers remain unaware about noise induced hearing loss as this is an insidious process, leading to temporary or permanent hearing impairment, but preventable. Pure Tone audiometric test is used to determine the degree of hearing loss in noise exposed individuals. Aim &amp; Objective: To nd the hearing threshold levels for high and mid frequency sounds for both ears in Professional drivers. To evaluate the preponderance of hearing loss between right and left ear using hearing thresholds. Materials &amp; Methods: This study was conducted in 100 Professional male drivers aged between 30-40 years who are working in Tamil Nadu State Transport Corporation, Madurai. Pure tone audiometry was used to measure the high and mid frequency hearing threshold levels in both ears. Results: The mean (SD) hearing threshold for high and mid frequency sounds was signicantly higher in left ear comparative to right ear with P value &lt; 0.05. The statistically signicant difference in hearing loss was observed between both ears. Conclusion : Our study showed statistically signicant higher hearing threshold for high and mid frequency sounds in left ear compared to right ear, that concludes left ear is more prone for hearing loss than the right ear

Music – A double edged sword for students in COVID scenario

Background: Hearing loss is often thought of as a natural phenomenon of the aging process. However younger people with repeated usage of ear phone music are reporting nowadays with hearing impairment and more during this COVID pandemic era. In today’s society, these devices are indispensable and are part of day‑to‑day life and because of the restriction on outdoor movement in COVID pandemic more and more people are reliant on ear phone music to allay boredom. Hence, this study was conducted to create awareness regarding prolonged exposure to loud noise either through an MP3 player or cell phone music. Materials and Methods: A prospective study was done compromising 400 students from Shri Adichunchanagiri Institute of Medical Sciences from March 2020 to December 2020. They were divided into four groups using a questionnaire, Group A comprising 100 students who had a habit of listening to music through ear phones at least 2 h a day, Group B comprising 100 students who are used to earphone music less than 1 h per day and Group C comprising of 100 students who very occasionally use ear phones, but hear music mostly through speakers and Group D comprising of 100 students who are not used to ear phone music. All the 400 students studied were attending online classes as per the college schedule which constituted 3-4 hours daily. All the groups were subjected to pure tone audiometry when they reported back to their regular offline classes as the pandemic reduced in January 2021 and the audiogram obtained. Results and Observations: The study revealed high frequency hearing loss in 6% of Group A and 2% in Group B; whereas, in there were no hearing impairment in Groups C and D indicating a significant role of prolonged ear phone music as a cause of high frequency hearing loss in students. The thin percentage and absence of hearing loss in Groups B, C, and D suggests the impact of the duration of exposure also has a role in the pathology. Conclusion: This study proves beyond doubt that the prolonged usage of loud ear phone music is harmful to the ears and also the COVID induced movement restriction precipitated the indiscriminate use of ear phone music which further increased the causation.

Analysis of influencing factors of high-frequency hearing loss among male noise workers in an automobile manufacturing enterprise

Objective: To analysis of high-frequency hearing loss status and risk factors among male noise workers in an automobile manufacturing enterprise in Guangzhou. Methods: From February 2020, a cluster sampling method was used to select 3486 male workers exposed to noise in an automobile manufacturing enterprise in Guangzhou in 2018. After screening, 2608 were selected as the research objects. Pure tone hearing threshold test, noise exposure level test and questionnaire survey were conducted, and the cumulative noise exposure was calculated. Chi square test and unconditional logistic regression were used to analyze the correlation between various factors and high frequency hearing loss. Results: The detection rate of high-frequency hearing loss in noise exposed workers was 34.20% (892/2608) , there were significant differences in the two groups among age, marital status, years of noise exposure, noise exposure equivalent A sound level, CNE, different working hours and exposure to electromagnetic radiation (P<0.05) . Multiple logistic regression analysis showed that age, CNE and exposure to electromagnetic radiation were independent risk factors for high-frequency hearing loss (P<0.05) , three shifts and two shifts were the protective factors for the occurrence of high-frequency hearing loss (OR=0.523, P<0.01) . Conclusion: Noise exposure is the main influencing factor of high-frequency hearing loss of noise-receiving workers in automobile manufacturing enterprises. Enterprises should strengthen noise control in the workplace, improve the working environment of electromagnetic radiation, and implement a scientific and healthy work shift system.

Role of LASER Stapedotomy in clinical improvement in subjective tinnitus among patients with Otosclerosis- a retrospective analysis

Objective: To determine the prevalence and severity of subjective tinnitus in patients undergoing LASER stapedotomy at the Department of Otorhinolaryngology, AIIMS Patna. To evaluate the efficacy of LASER stapedotomy in clinically significant improvement in tinnitus in these patients Materials and methods: A retrospective study was conducted on 40 patients who underwent LASER stapedotomy from February 2018 to December 2019 at the Department of Otorhinolaryngology, AIIMS Patna. Pre- and post-operative audiological and tinnitus assessment was done. Hospital records were analyzed and otosclerotic patients with subjective tinnitus were included in the study. Prevalence and severity of tinnitus and accompanying degree of hearing loss across both genders were noted. Improvement in tinnitus postoperatively was evaluated. Results were analyzed using IBM SPSS Statistics software Version 20. Mean values were calculated and paired t-tests were applied to assess the role of LASER stapedotomy on tinnitus improvement. Results: Out of a total of 40 stapedotomy patients, 29 (72.50%) had tinnitus at presentation. The mean age of these patients was 29.59±9.3 years. The mean gain in air conduction threshold (ACT) and air-bone gap (ABG) closure was 19.68 dB and 12.14 dB respectively. Unilateral tinnitus was seen in 55.17% and bilateral in 44.83% of patients. High-frequency hearing loss was found in 65.51% of patients. Postoperatively, 44.83% of patients experienced a complete resolution in tinnitus, while all of them had an improvement in tinnitus severity. This result was similar in both males and females. Conclusion: Tinnitus is a frequent complaint of patients suffering from otosclerosis, which often takes a backseat in the treatment goals of a surgeon. It varies in severity and duration and is associated with a progressive worsening of hearing thresholds. LASER stapedotomy is an effective treatment modality, which not only improves post-operative hearing but also alleviates tinnitus to a great extent. Study design: A retrospective observational study Keywords: Otosclerosis. Tinnitus, LASER stapedotomy, Air Bone Gap (ABG)

Hearing Loss-a Camouflaged Manifestation of COVID 19 Infection.

The symptomatology of novel Severe Acute Respiratory Syndrome Corona virus type 2 infection runs the entire gamut of mild to moderate and serious illness among the affected individuals. As listed in recent literature, respiratory, cardiovascular, gastrointestinal, olfactory and gustatory systems are commonly involved. With the growing knowledge about the disease, varied manifestations have been identified and lately, otorhinolaryngology dysfunctions in COVID 19 have been described. Hearing loss in COVID era is one of the emerging areas of concern and calls for further research in the field for the better understanding and treatment of this entity. This study was designed to assess the audiological profile among 100 mild to moderately affected COVID-19 individuals, so as to make a contribution to the emerging literature on otologic manifestations in COVID 19. In our case series, high frequency hearing loss and referred OAE was noted among significant number of COVID 19 positive patients. This was even observed in patients without any otologic symptoms. Hence, early identification and intervention if required helps to give a better quality of life to the patient.

Development of Phoneme Perception Test for School-Aged Children

Purpose: The purpose of the present study was to develop lists of phoneme perception tests for school-aged children.Methods: The 127 initial and 94 final consonant test items were modified by the difficulty level (reduced the number for the multiple-choice and controlled familiarity of target words and foil words). The validity of the results for normal hearing children was evaluated. Through discussions by experts in various fields, the target word list was revised. Words with a low percentage (&lt;90%) of correct answers, vowel-consonant in an initial consonant test item, and consonant-vowel (CV) in final consonant item were eliminated and produced the last revised consonant perception test item for school-aged children.Results: The consonant test item consisted of three multiple-choice words type of consonant-vowel-consonant or CV. The 50 initial and 25 final consonant perception test items included the high degree of familiarity, corresponding frequency of phonemes for daily life speech sounds of children.Conclusion: To analyze the phoneme perception ability of school-age children by listening and to evaluate phoneme errors in children with congenital high frequency hearing loss, the results of this study are useful.

Examination of the Relation Between Audiometric Configuration and Hematological Parameters in Idiopathic Sudden Sensorineural Hearing Loss.

Among the hematological parameters, neutrophil/lymphocyte ratio (NLR) and platelet/ lymphocyte ratio (PLR) have been associated with inflammatory state, microvascular damage and ischemia. It is well-known that these ratios increase in idiopathic sudden sensorineural hearing loss (ISSHL). In ISSHL, different audiographic features may reflect different disease mechanisms. This study aimed to investigate whether there were differences in NLR and PLR among patient groups with different audiometric configurations. Patients meeting the study inclusion criteria were divided into four groups according to their audiogram configurations. Mean NLR and PLR values of the patient groups were compared among themselves and versus control group. The study was conducted with 166 participants. Mean NLR values were 3.07 ± 2.48, 3.30 ± 2.70, 5.24 ± 3.71, 3.57 ± 3.19 and 1.51 ± 0.68 for ascending, flat, descending and total/subtotal audiometric configuration groups and control group, respectively. Mean PLR values were 145.2 ± 126.7, 130.9 ± 57.8, 192.2 ± 94.4, 143.7 ± 70.8 and 94.1 ± 24.7 for ascending, flat, descending, total/subtotal audiometric configuration groups and control group, respectively. Both NLR and PLR were significantly greater in patients from all configuration groups than in control group (p < 0.05). In addition, the group with descending audiometric configuration showed significantly higher mean NLR and PLR compared to other audiometric configuration groups (p < 0.05). The highest level of inflammation was detected in the ISSHL patient group with high frequency hearing loss and descending audiographic configuration.

The effect of different diagnostic standards on the diagnosis of suspected occupational noise-induced deafness

Objective: To explore the effect of different diagnostic criteria on occupational noise-induced deafness (Onid) , and to provide theoretical basis for the revision of ONID diagnostic criteria. Methods: From January 2016 to January 2018, the physical examination results of noise-exposed workers during occupational health examination in Qingyuan Occupational Disease Prevention and Treatment Hospital were retrospectively investigated in September 2019, with Gbz 49-2014《diagnosis of occupational noise deafness》as the study object, 471 workers suspected of Onid were weighted with different combinations of high frequency hearing threshold, and the better ear weight was calculated, compared with the diagnostic criteria of 2007 and 2014, the degree of hearing loss was evaluated. SPSS 22.0 was used for statistical analysis, χ(2) test was used for counting data, and non-parametric test was used for measuring bias data. Results: The average age of 471 subjects was (40.32±7.01) years, and the average age of exposure to noise was (7.11±3.44) years. On the basis of the 2007 edition diagnostic standard, the suspected ONID diagnostic rate of different high frequency auditory threshold was increased by 16.35% and 30.15% at 3.0 kHz, 6.0 kHz increased by 20.17%, 3.0 kHz+4.0 kHz increased by 22.29%, 3.0 kHz+6.0 kHz increased by 17.20%, 4.0 kHz+6.0 kHz increased by 25.27%, the differences were statistically significant (P<0.05) , the frequency of 3.0 kHz+4.0 kHz+6.0 kHz increased by 22.29%. Using the 2014 edition diagnostic standard, the diagnostic rate of Onid was reduced by 30.15% and 13.80%, 6 kHz is 9.98% lower, 3.0 kHz+4.0 kHz is 7.86% lower, 3.0 kHz+6.0 kHz is 12.95% lower, 4.0 kHz+6.0 is 4.88% lower, the high frequency of 3.0 kHz+4.0 kHz+6.0 kHz decreased by 7.86%, the differences were statistically significant (P<0.05) . Conclusion: The diagnosis rate of suspected Onid is increased by weighting different high frequency hearing threshold, in which the weighted 4kHz high frequency has the greatest influence on the result, and the weighted 3 kHz high frequency has the least.

High frequency hearing loss detection rate in occupational noise exposed workers in China: a Meta-analysis

Objective: A Meta-analysis was used to evaluate the high frequency hearing loss detection rate, its area and time distributions in occupational noise exposed workers in China to provide evidence for the prevention and control of occupational noise-induced deafness. Methods: From February to April 2020, the number of hearing tests and the number of binaural high frequency average hearing threshold ≥40 dB of workers exposed to noise in key occupational disease monitoring and occupational health risk assessment project in China was collected from China National Knowledge Infrastructure (CNKI) , VIP database and PubMed database. The retrieval time was set from the establishment of the database to February 28, 2020. The R 3.6.2 software was used to calculate the pooled high frequency hearing loss detection rate. Results: A total of 28 studies, included 34 data and 1259571 occupational noise exposed workers, were enrolled. The articles covered 16 provinces in 2015-2018. The pooled high frequency hearing loss detection rate in occupational noise exposed workers was 9.45% (95%CI: 7.64%-11.64%) . The high frequency hearing loss detection rate (10.54%) was higher in 2018 than other years (2017: 10.17%, 2016: 9.21%, 2015: 7.88%) . The high frequency hearing loss detection rate (12.23%) was higher in central China than in eastern (10.21%) , western (7.91%) and north-eastern (5.21%) China. Conclusion: The overall high frequency hearing loss detection rate in occupational noise exposed workers is generally high in China. It is important to strengthen the hearing protection in occupational noise exposed workers to facilitate the occupational noise-induced deafness prevention and control in China.

Chronic Oral Selegiline Treatment Mitigates Age-Related Hearing Loss in BALB/c Mice.

Age-related hearing loss (ARHL), a sensorineural hearing loss of multifactorial origin, increases its prevalence in aging societies. Besides hearing aids and cochlear implants, there is no FDA approved efficient pharmacotherapy to either cure or prevent ARHL. We hypothesized that selegiline, an antiparkinsonian drug, could be a promising candidate for the treatment due to its complex neuroprotective, antioxidant, antiapoptotic, and dopaminergic neurotransmission enhancing effects. We monitored by repeated Auditory Brainstem Response (ABR) measurements the effect of chronic per os selegiline administration on the hearing function in BALB/c and DBA/2J mice, which strains exhibit moderate and rapid progressive high frequency hearing loss, respectively. The treatments were started at 1 month of age and lasted until almost a year and 5 months of age, respectively. In BALB/c mice, 4 mg/kg selegiline significantly mitigated the progression of ARHL at higher frequencies. Used in a wide dose range (0.15–45 mg/kg), selegiline had no effect in DBA/2J mice. Our results suggest that selegiline can partially preserve the hearing in certain forms of ARHL by alleviating its development. It might also be otoprotective in other mammals or humans.

The Effect of Nonlinear Frequency Compression on Acoustic Change Complex Responses in High-Frequency Dead-Regioned Hearing Loss.

The study is concern with the distinguishing of the stimuli containing high frequency information with the frequency compression feature at the cortical level using the acoustic change complex (ACC) and the comparison of such with the ACC answers of individuals with normal hearing. This is a case-control study. Thirty adults (21 males and nine females) with normal hearing, ranging in age between 16 and 63 years (mean: 36.7 ± 12.9 years) and 20 adults (16 males and four females) with hearing loss ranging in age between 16 and 70 years (mean:49.0 ± 19.8 years) have been included in this study. A total of 1,000 ms long stimulus containing 500 and 4,000 Hz tonal stimuli was used for ACC recording. The start frequency (SF) and compression ratio (CR) parameters of the hearing aids were programmed according to the default settings (SFd, CRd) in the device software, the optimal setting (SFo, CRo), and the extra compression (SFe, CRe) requirements and ACC has been recorded for each condition. Evaluation has been performed according to P1-N1-P2 wave complex and ACC complex wave latencies. Independent samples t-test was used to test the significance of the differences between the groups. In all individuals ACC has been observed. There was a significant difference between the wave latencies in normal hearing- and hearing-impaired groups. All wave latency averages of the individuals with hearing impairment were longer than the individuals with normal hearing. There were statistically significant differences between SFd-SFo, SFd-SFe, and SFo-SFe parameters. But there was no difference between CRd, CRo, and CRe in terms of CRs. In order to discriminate high frequency information at the cortical level we should not rely on default settings of the SF and CR of the hearing aids. Optimal bandwidth must be adjusted without performing insufficient compression or over-compression. ACC can be used besides the real ear measurement for hearing aid fitting.

Prevalence of hearing loss and influencing factors among workers in Wuhan, China.

We aimed to estimate the prevalence of hearing loss and influencing factors among workers in automobile manufacturing industry in Wuhan, China. We conducted cross-sectional analyses of 2017 through 2019 data from survey of the key occupational diseases on 17,176 workers in automobile manufacturing industry, Wuhan, China. Hearing loss was defined as a pure tone mean of 25 dB or higher in either ear at 0.5, 1, and 2 kHz for speech frequency and at 3, 4, and 6 kHz for high frequency. Among the 17,176 workers, more than a quarter of participants had high frequency hearing loss, and 6.41% had speech frequency hearing loss. The prevalence of hearing loss was higher among participants with diabetes mellitus and current smoking, temporary tinnitus, and sudden change in hearing. Compared with the controls, age (OR = 1.08, 95% CI = 1.08-1.09), male (OR = 1.40, 95% CI = 1.21-1.63), occupational noise exposure (OR = 1.19, 95% CI = 1.08-1.30), having temporary tinnitus (OR = 1.20, 95% CI = 1.08-1.33), and having sudden change in hearing (OR = 1.58, 95% CI = 1.20-2.08) were associated with higher prevalence of high frequency hearing loss; meanwhile, age (OR = 1.09, 95% CI = 1.08-1.09), male (OR = 1.38, 95% CI = 1.11-1.71), having family history of hearing loss (OR = 2.84, 95% CI = 1.35-5.97), and having sudden change in hearing (OR = 2.58, 95% CI = 1.80-3.70) were associated with higher prevalence of speech frequency hearing loss. No additive and multiplicative interaction was found between occupational noise and these factors for hearing loss. Hearing loss directly affects 25% of workers in automobile manufacturing industry in Wuhan. Measures should be implemented for the control of occupational noise and other factors simultaneously in the workplace.

Does inflammation play a role in the pathophysiology of tinnitus?

The present study aimed to investigate the potential of neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR) and mean platelet volume (MPV) as prognostic markers in tinnitus patients at inflammatory process. This study consisted of 216 subjects (124 males and 92 females), Routine laboratory CBC test results were calculated in this study. All the patients were divided into three groups according to their hearing thresholds: a high frequency hearing loss-tinnitus group (HFHL-TN) consisted of 55 subjects, an hearing loss in all frequencies tinnitus group (AFHL-TN) consisted of 53 subjects and a normal hearing-tinnitus group (NH-TN) consisted of 51 subjects. The control group (CNT) included 57 age-and sex-matched healthy subjects. NLR, PLR and MPV were observed in the HFHL-TN group when compared to AFHL-TN, NH-TN and CNT group (P < 0.001). An increase in NLR was observed in the AFHL-TN group compared with the CNT group (P = 0.004). The PLR value of the HFHL-TN group was significantly higher than that of the AFHL-TN (P = 0.028) and NH-TN,CNTgroup (P < 0001). The PLR value of the HFHL-TN group was significantly higher than that of the AFHL-TN (p=0.028) and NH-TN, CNT group (P < 0001). MPV values in HFHL-TN group was slightly higher AFHL-TN group and significantly higher than NH-TN (P = 0.025) and CNT (P < 0.001) group. Our results confirm that elevated NLR, PLR and MPV values has been suggested to be a useful inflammatuar prognostic biomarker of tinnitus patients.

The Influence of Non-Linear Frequency Compression on the Perception of Speech and Music in Patients with High Frequency Hearing Loss.

Background and ObjectivesNon-linear frequency compression (NLFC) technology compresses and shifts higher frequencies into a lower frequency area that has better residual hearing. Because consonants are uttered in the high-frequency area, NLFC could provide better speech understanding. The aim of this study was to investigate the clinical effectiveness of NLFC technology on the perception of speech and music in patients with high-frequency hearing loss.Subjects and MethodsTwelve participants with high-frequency hearing loss were tested in a counter-balanced order, and had two weeks of daily experience with NLFC set on/off prior to testing. Performance was repeatedly evaluated with consonant tests in quiet and noise environments, speech perception in noise, music perception and acceptableness of sound quality rating tasks. Additionally, two questionnaires (the Abbreviated Profile of Hearing Aid Benefit and the Korean version of the International Outcome Inventory-Hearing Aids) were administered.ResultsConsonant and speech perception improved with hearing aids (NLFC on/off conditions), but there was no significant difference between NLFC on and off states. Music perception performances revealed no notable difference among unaided and NLFC on and off states. The benefits and satisfaction ratings between NLFC on and off conditions were also not significantly different, based on questionnaires, however great individual variability preferences were noted.ConclusionsSpeech perception as well as music perception both in quiet and noise environments was similar between NLFC on and off states, indicating that real world benefits from NLFC technology may be limited in Korean adult hearing aid users.