Otoacoustic Emission Testing Research Articles

Evaluation of inner ear and hearing functions in lichen planus patients.

Lichen planus (LP), which affects skin, nails, hair, and mucosal surfaces, is a chronic, autoimmune, and inflammatory disease, and autoimmune diseases may affect the inner ear. This study aims to investigate hearing and inner ear functions of the LP patients. The present study was formed by 49 patients who were clinically and histopathologically diagnosed with LP and did not receive any treatment. The healthy group consisted of 52 healthy individuals. Pure tone audiometry (PTA) and distortion product otoacoustic emission tests were used in the hearing evaluation. At frequencies of 1, 2, 4, 6, and 8 kHz in the right ear and 0.5, 1, 2, 4, 6, and 8 kHz in the left ear in PTA, the lichen group's hearing thresholds were higher than the healthy group's. Upon comparing the hearing thresholds of LP patients with oral mucosa involvement and LP patients without oral mucosa involvement, there were significant differences between the groups at 1, 4, and 8 kHz in the right ear and at 0.25, 0.5, 2, 4, 6, and 8 kHz in the left ear. Because of the increasing hearing thresholds, we think that hearing and inner ear functions of LP patients, particularly with oral mucosal involvement, are negatively affected.

Prognostic value of vestibular evoked myogenic potential and distortion product otoacoustic emission tests in patients with a diagnosis of sudden hearing loss: A preliminary report

Objectives: This study aims to investigate whether vestibular evoked myogenic potentials (VEMPs) and distortion product otoacoustic emissions (DPOAEs) have prognostic values in the follow-up of patients diagnosed with idiopathic sudden sensorineural hearing loss (ISSNHL) with audiological tests. Patients and Methods: Between June 2013 and January 2014, a total of 27 patients (11 males, 16 females; mean age: 44.9±13.8 years; range, 18 to 60 years) diagnosed with ISSNHL at their first admissions and underwent VEMP and DPOAE tests were included. As the treatment protocol, steroid treatment combined with hyperbaric oxygen therapy was initiated in all patients. At the second month of the treatment, all patients underwent VEMP and DPOAE tests once again. Hearing recovery was evaluated based on the hearing improvement, compared to the unaffected contralateral ear. Results: The median recovery rate was statistically significantly higher in the patients with normal pre-treatment VEMP test results than those with abnormal VEMP test results (p=0.023). The median recovery rate was statistically significantly higher in the patients with normal post-treatment VEMP test results compared to those with abnormal post-treatment VEMP test results (p=0.031). The median recovery rate was also statistically significantly higher in the post-treatment DPOAE test positivity than the post-treatment DPOAE test negativity (p<0.001). Conclusion: Our study results suggest that, in the follow-up of the prognosis of ISSNHL disease, VEMP test may have a prognostic value, while DPOAE test is an important parameter which can be used in the monitorization of the disease.

Maternal Diabetes: A Potential Risk Factor of Congenital Hearing Loss

Objective. The purpose of this study is to identify the incidence rate of 'refer' result in neonates born to diabetic mothers and to determine the association of maternal diabetes and the initial 'refer' result.
 Methods. This was a retrospective cross-sectional study which included neonates who had hearing screening test using transient-evoked otoacoustic emissions test (TEOAE) on both ears at the Philippine General Hospital Ear unit during three weeks. We obtained the demographic characteristics, presence/absence of maternal diabetes, and OAE results.
 Results. Among the 150 neonates, ten were born to diabetic mothers, with an age range of 2-8 days old. Forty percent of neonates of diabetic mothers had an initial 'refer' result compared with 7.9% of nondiabetic mothers' neonates. After logistic regression analysis, there is a significant association between maternal diabetes and initial 'refer' result in OAE with a p-value <0.05. If the mother is diagnosed with diabetes (gestational/pre-gestational), the odds of having an initial 'refer' result in the hearing screening is 2x higher. The odds can range from 2-43 times.
 Conclusion. The incidence rate of an initial 'refer' result in neonates of diabetic mothers is 40%. There is a significant association between maternal diabetes and the initial 'refer' result in the OAE test.

UNHS: A Decade Long Feasibility and Sustenance Study from a Tertiary Care Hospital in India.

Objective The aim of this study is to estimate the incidence of hearing loss in neonates at a tertiary referral center, to assess the associated risk factors in those identified with hearing loss and to explore the challenges of starting and continuing a universal neonatal hearing screening programme in a tertiary care hospital over a decade. Materials and Methods It is a cohort prospective observational study conducted from January 2008 to January 2018. Five thousand five hundred and forty neonates underwent screening for hearing loss, of which 2688 were well babies and 2854 babies had one or more risk factors causing hearing loss. Otoacoustic emissions (OAE) is employed as the first level of screening within one month of birth. Brainstem evoked response audiometry (BERA) is done at 3months of gestational age for all the well babies who were referred on OAE testing and all the high risk babies irrespective of the result of the OAE screening. The High risk criteria are based on the set criteria by the Joint Committee on Infant Hearing (2007) and American Academy of Pediatrics (1994). Results In our study the incidence of hearing impairment is 5.41 per 1000 neonates screened. In well babies and at risk babies it is 1.49 and 9.11 per 1000 respectively.The common neonatal risk factors associated with hearing loss in our study are babies admitted to neonatal intensive care units (NICU), intrauterine growth retardation (IUGR), birth weight less than 1500g, respiratory distress syndrome (RDS) and hyperbilirubinemia. Conclusion The incidence of hearing loss in our study is comparable to that reported in literature (Bachmann KR, ArvedsonJC (1998) Early identification and intervention for children who are hearing impaired. Pediatr Rev. 1998 May; Vol. 19. No.5. pp. 155-165. http://www.ncbi.nlm.nih.gov/pubmed/9584525 Accessed from May 1998, Nagapoornima P, Ramesh A, Srilakshmi, Rao S, Patricia PL, Gore M, et al. Universal hearing screening. Indian J Pediatr. 2007 Jun 18; 74(6):545-9., Augustine AM, Jana AK, Kuruvilla KA, Danda S, Lepcha A, Ebenezer J, et al. (2014) Neonatal hearing screening-experience from a tertiary care hospital in southern India. Indian Pediatr. Vol. 51. No.3. pp 179-183. http://www.ncbi.nlm.nih.gov/pubmed/24277966 Accessed from Mar 2014). Hearing loss is more common in those babies with risk factors as reported in literature (Nagapoornima P, Ramesh A, Srilakshmi, Rao S, Patricia PL, Gore M, et al. Universal hearing screening. Indian J Pediatr. 2007 Jun 18; 74(6):545-9. http://www.ncbi.nlm.nih.gov/pubmed/21654001 Paul AK (2011) Early identification of hearing loss and centralized newborn hearing screening facility-the Cochin experience. Indian Pediatr. Vol. 48. No. 5. pp 355-359. Accessed from May 2011). Implementation of neonatal hearing screening program at a tertiary care hospital using a two tier system with OAE and BERA is a feasible but challenging service.

Ototacoustic Emissions-Based Hearing Assessment of Neonates in Tertiary Care Hospital.

Hearing is a special sense needed for appropriate mental, speech and language development and academic performance. Even among normal babies, 50% of cases of hearing loss are missed out if screening protocol is not followed. In this study, we assess the hearing of all neonates born and brought to the tertiary care hospital, and also find out how many well babies with hearing loss would have been missed if this screening had not been done. Hence, the study aims to estimate the prevalence of neonatal hearing loss and study the associated risk factors. Neonates (N = 1559) attended the outpatient department of paediatrics were included. A detailed history of the neonates with special emphasis on prenatal, natal, postnatal, family history, and maternal risk factors were elicited. Three-stage hearing testing protocol was followed with transient evoked otoacoustic emission testing, a gold standard test for stage 1 and 2 and brainstem evoked response audiometry for stage 3. Of 1559 neonates, 138 had hearing loss. History of drug intake, order of the child, place of delivery and maternal history were the significant factors associated with hearing loss in neonates. Bivariate analysis revealed order of child, maternal history, and history of drug taken were the significant factors affecting the hearing loss in the neonates (P < 0.001). The prevalence of hearing loss was 8.85%. Early detection of hearing loss is essential for timely intervention and development of optimal communication skills. Further studies are required to decide the essentiality of Universal New-born hearing screening.

290 Lack of an association between prenatal nicotine exposure and offspring’s hearing

Maternal smoking is hypothesized to contribute to childhood hearing dysfunction; data on laboratory proven exposure are limited. We aimed to test for an association between in-utero exposure to nicotine and infant hearing dysfunction. Secondary analysis of a multicenter randomized trial to prevent congenital CMV infection among gravidas with primary CMV infection. Monthly IVIG therapy did not influence rate of congenital CMV. Dyads with missing urine, fetal or neonatal demise, and those with infants diagnosed with a major congenital anomaly, congenital CMV infection, or with evidence of middle ear dysfunction were excluded. The primary outcome was neonatal hearing impairment in at least one ear defined as amplitudes on otoacoustic emissions (DPOAE) test below frequency-specific cutoff for ≥50% of the frequencies tested, assessed within 42 days of birth. Cotinine was measured via commercially available ELISA kits in maternal urine collected at enrollment and third trimester (mean GA 16.0 and 36.7 weeks respectively). Blinded personnel ran samples in duplicates. Maternal urine cotinine >5 ng/ml at either time point defined in-utero exposure to nicotine. Multivariable logistic regression included variables associated with the primary outcome (P <0.1) and with the exposure (P <0.05) in univariate analysis. Of 399 enrolled patients, 150 were included in this analysis; 46 had evidence of nicotine exposure (Table 1). The primary outcome occurred in 18 newborns; with 15.2% in tobacco-exposed infants versus 10.6% in non-exposed (OR 1.52, 95% CI 0.55 – 4.20). This association was similar when exposure was stratified as heavy (>100ng/ml, OR 1.54, 95% CI 0.45-5.29) or mild (5-100ng/ml, OR 1.49, 95% CI 0.38-5.92). There was no association between nicotine exposure and frequency-specific amplitudes. Findings remained statistically non-significant on multivariable analysis. We did not demonstrate that prenatal nicotine exposure is associated with hearing dysfunction assessed on DPOAE in newborns exposed to maternal CMV infection. Larger studies with long-term follow up are needed.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

There is no evidence of cochlear and vestibular melanocyte damage in patients with alopecia areata.

Follicular melanocytes are known to be damaged in alopecia areata (AA). However, it is not clear whether melanocytes are the primary target of autoimmunity and whether melanocytes in the inner ear are affected. This study aimed to detect possible cochlear and/or vestibular melanocyte damage in AA patients. Thirty-two AA patients and 35 sex- and age-matched healthy volunteers were evaluated between November 2018 and March 2020 at the Karabük University Training and Research Hospital. The conventional pure tone audiometry test and distortion product otoacoustic emission test were performed to evaluate hearing. To evaluate the vestibular function, the following tests were performed: the vestibulospinal reflex tests (Romberg test, tandem stance test and tandem walking test); positional balance tests (Dix-Hallpike test, supine roll test and head hanging test); vestibulo-ocular reflex tests (caloric test, head shake test) and oculomotor tests (saccade, smooth pursuit and optokinetic). The mean age of AA patients was 31.94±11.86years (range, 15-67years). There were no significant differences in the results of the hearing and balance tests between the groups. Furthermore, disease parameters (duration of the last attack, recurrence, positive family history, positive pull test, the severity of the disease, etc) were not associated with hearing loss and vestibular damage. AA patients did not exhibit hearing loss or balance abnormalities that would indicate cochlear and vestibular melanocyte damage. The lack of damage to the inner ear melanocytes in AA patients may indicate that follicular melanocytes are affected secondary to autoimmune damage in the hair bulb, and melanocytes are not the primary target in the pathogenesis of AA.

Detecting Intralabyrinthine Pressure Increase by Postural Manipulation with Wideband Tympanometry and Distortion Product Otoacoustic Emissions.

Intracranial pressure increase is known to affect inner ear pressure through the cochlear and vestibular aqueducts. This finding forms a good model for inner ear pressure studies. Standard techniques used to detect this pressure increase are neither reliable nor easily repeatable or cheap. Studies with immitancemetry and otoacoustic emissions have been giving hopeful results. This study aims to confirm the results in the literature with wideband tympanometry and add a new parameter of otoacoustic emissions to inner ear pressure testing. Wideband tympanometry (WBT) and distortion product otoacoustic emissions (DPOAE) tests were applied to 40 healthy participants in sitting, supine, and Trendelenburg positions. DPOAE were measured under ambient or peak pressure. Resonance frequency, tympanic peak pressure, 1000, 1500, 2000, 3000, 4000, and 6000 Hz frequencies in DPOAE were measured. The increase in the tympanic peak pressure and the decrease in resonance frequency (RF) due to position change were found statistically significant (p<0.01). Signal noise ratio (SNR) decrease at 1 kHz frequency and SNR increase at 2, 3, 6 kHz in the normal protocol, SNR decrease at 1 kHz in the pressurized protocol were found statistically significant (p<0.01). RF in WBT and 1 kHz DPOAE SNR parameters were found useful in supporting the diagnosis in pathologies that increase intracranial pressure and inner ear pressure. Future research may ease their widespread use in clinical practice as they are non-invasive and rapidly applicable.

Protective Effect of Carvacrol against Paclitaxel-Induced Ototoxicity in Rat Model.

This study aimed to explore whether carvacrol (CV) had a protective effect on paclitaxel-induced ototoxicity from biochemical, functional, and histopathological perspectives. Forty Wistar albino male rats were randomly separated into five groups of eight rats. Group 1 was the control group, so Paclitaxel or CV was not administered. Group 2 was administered i.p. CV at 25 mg/kg once a week; Group 3, was administered i.p. paclitaxel at 5 mg/kg once a week; Group 4 was administered i.p. paclitaxel at 5 mg/kg followed (30 min later) by CV at 25 mg/kg once a week; and Group 5 was administered i.p. CV at 25 mg/kg followed (1 day later) by paclitaxel at 5 mg/kg. once a week. The drugs were administered intraperitoneally once a week for four consecutive weeks, and distortion product otoacoustic emissions (DPOAE) tests were performed at the beginning of the study before the first drug administration and at the end of the study after the last drug administration. All rats were sacrificed, and cochleae were removed for biochemical and histopathological analysis. Biochemical data indicated that paclitaxel caused oxidative stress in the cochlea. Histopathological findings revealed the loss of outer hair cells in the organ of Corti (CO) and moderate degenerative changes in the stria vascularis (SV). It was observed that DPOAE measurements were significantly reduced at high frequencies. In groups which CV was administered together with paclitaxel, these biochemical, histopathological, and functional changes were favorably reversed. CV may have a protective effect against paclitaxel-induced ototoxicity when given.

Melatonin reduces radiation damage in inner ear.

The purpose of this study was to use a murine model to determine if melatonin can protect the inner ear from radiation-induced damage. A total of 81 4-week-old Balb/c mice were randomly divided into five groups: control group; 50 mg/kg melatonin group; 5 mg/kg melatonin+radiotherapy group; 50 mg/kg melatonin+radiotherapy group; radiotherapy group. The radiotherapy groups received 16 Gy irradiation and melatonin was administered by intraperitoneal injection 30 min before radiotherapy. On days 3 and 7 after irradiation the function of outer hair cells was determined by auditory brainstem response (ABR) and distortion product otoacoustic emissions (DPOAEs) testing, pathological changes of inner ear cells were observed by light microscopy, and the expression of prestin mRNA was determined. ABR thresholds were increased and wave I latencies were extended after radiotherapy; however, the increases were lower in the groups that received melatonin (P < 0.05). DPOAEs showed radiotherapy-induced hearing loss at 8–12 kHz, and hearing loss was greater on day 7 than day 3. However, hearing loss was less in the melatonin groups (P < 0.05). Histopathological examination showed irradiation resulted in breaks and distortion of the cochlear basement membrane, disruption of the stria vascularis, and swelling of outer hair cells. Melatonin reduced these changes. Radiotherapy upregulated prestin mRNA expression. Radiotherapy-induced upregulation of prestin was decreased in the melatonin groups (P < 0.05), and the decrease was greater in the 50 mg/kg melatonin group (P < 0.05). Melatonin protects against radiation-induced cochlear damage by reducing damage to outer hair cells.

Perinatal factors influencing the neonatal hearing screening results

BackgroundPrevious studies have indicated that the majority of cases with “failed” results related to transient evoked otoacoustic emissions (OAE) test have the normal hearing. The present study aimed to assess the possible relationships between perinatal factors and the false-positive OAE results.MethodsA case-control study was carried out in an Iranian Hospital in 2020. Based on the OAE results on the first day of life, newborns were divided into 2 groups; Control group included subjects with “Pass” OAE results. Every neonate with “Fail” OAE result was referred for auditory brainstem response (ABR). Neonates with bilateral fail OAE but normal ABR results (false-positive OAE) were considered as the case group. All recorded data were analyzed to assess the possible correlations between maternal/neonatal factors and the false-positive OAE results.ResultsOne hundred and eighty-one neonates entered the study. Of all included neonates, 87 (48.1%) cases showed bilateral fail OAE and 94 (51.9%) subjects passed the OAE test. Normal ABR results (false-positive OAE) were observed in all cases with bilateral fail OAE. Comparisons of variables affecting the OAE results showed that of all perinatal factors, neonate’s sex (p = 0.046) and cesarean section (p = 0.003) were the only influencing factors that increased the risk of false-positive OAE results.ConclusionBased on the results, the cesarean section delivery and neonate’s male sex increased the risk of false-positive results related to OAE test. Implementing other screening tests such as ABR or Automated ABR as the initial screening test could be suggested for such cases.

Relation between Mode of Delivery and Findings of Oto-Acoustic Emission Test Results

Introduction: Hearing loss, since birth, is an important public health issue round the globe with a prevalence ranging from 2-3/1000 live births. Neonates born by Caesarean Delivery (CD) refer for Oto-Acoustic Emissions (OAE) test more frequently compared to Vaginal Delivery (VD) soon after birth. During this study, the effects of the modes of delivery on the OAE test results were investigated. Aim: To study the effects of modes of delivery on the OAE test results. Materials and Methods: During this study 500 neonates, born beyond 37 weeks of gestation, at Dhiraj Hospital, Gujarat, India between January 2019-July 2019 without any associated risk factors were enrolled and divided on basis of their mode of delivery-vaginal or caesarean section. Before their discharge from hospital, OAE test was performed on the patients. Modes of delivery and OAE test results were collected and analysed. Results: Results reviled that there was a significant difference in OAE test failure rates between the two delivery mode groups. CD was significantly related to failed OAE. CD infants had a three-fold higher failure rate as compared to VD infants in OAE test (4.12% vs 1.3%). Conclusion: Neonates born by CD had significantly higher failure rates on first OAE as compared to VD. This shows that the mode of delivery contains a significant effect on the results of the hearing screening tests.

Neonatal Screening for Congenital Hearing Loss in the North of Jordan; Findings and Implications.

Background:Congenital hearing loss is one of the important illnesses that affect newborns. Early diagnosis and treatment are a challenge for medical authorities in developing countries to improve children's functional, intellectual, emotional, and social abilities. We aimed to study the prevalence of congenital hearing loss in northern Jordan community and identify factors that could affect hearing screening protocol.Methods:Prospective cross-sectional study of 1595 infants born in our hospital underwent hearing screening tests. Totally, 104 were tested in NICU and the rest examined in the nursery room using Otoacoustic emission (OAE) test as a primary testing tool. The patients were followed in the three hearing screening phases. Factors affecting screening results were studied and analyzed.Results:The total number of newborns who didn't pass the first OAE test in one or both ears were 90 (5.6%); 69 from the nursery group and 21 from the NICU group. In the 2nd screening phase 21 (23.3%) didn't attend the appointment. Sixty-four passed the second screening OAE test. Five newborns (5.6%) had a second refer result in one or both ears and referred for a diagnostic ABR test. Three infants passed the test and two found to have bilateral hearing loss.Conclusions:Hearing screening test is conducted via a 3-phases-protocol. OAE is used in the first two phases and ABR in the third phase. Hearing results is significantly affected for infants admitted to NICU. The following factors increase OAE fail response: mechanical ventilation for more than 5 days, Hyperbilirubinemia, associated congenital anomalies. Mode of delivery doesn't have statistical significance on hearing screening results.

Comparison of Pre-treatment and Post-treatment Auditory Brainstem Response Results in Children with Serous Otitis

Introduction: The present study aimed to investigate the effect of middle ear effusion on the ABR test through a comparison of clinical auditory brainstem response (ABR) results in pre-treatment and post-treatment in patients diagnosed with otitis media with effusion (OME). Materials and Methods: This retrospective study included 42 children aged 3 months-12 months, who failed the otoacoustic emissions (OAE) test in the hearing screening program and were diagnosed with serous otitis. Results: Following treatment of the patients, the right ears of 76.9% of patients and the left ears of 69.04% of patients passed the distortion product otoacoustic emissions test. In the OAE tests post-treatment, in 23.8% of patients, the right ear, and 30.95% patients, the left ear was negative, and a decrease was seen in the hearing thresholds in clinical ABR. The latencies of the ABR 1st and 3rd waves were observed to be significantly prolonged pre-treatment compared to post-treatment in all patients. Conclusion: The appropriate intervention in the early stage eliminates or reduces the negative effects of hearing loss. To avoid a very long follow-up period of infants diagnosed with serous otitis media in the first years of life, prompt treatment should be applied to patients who have not responded to medical treatment, and if the thresholds after treatment are above normal values, a hearing aid should be applied as soon as possible and family therapy should be provided.

Our newborn hearing screening results.

OBJECTIVE:The aim of the study was to evaluate the results of neonatal hearing screening in our hospital with the help of literature and to question and reveal the risk factors to gain healthy individuals and to raise awareness for all health workers and the public who are interested in this subject.METHODS:A total of 16,388 newborn infants were evaluated between October 2009 and January 2018. All newborns were screened with transient evoked otoacoustic emissions (TEOAEs) test. Risk factors were investigated. The test repetition and auditory brainstem response (ABR) measurements were performed on newborns who could not pass the TEOAE test and the newborns in the risky group after 15 days.RESULTS:A total of 116 newborns (0.7%) were suspected to have hearing loss. Twenty-seven newborns (0.16%) were found to be in intensive care unit. Twelve newborns (0.07%) had permanent hearing loss. Then, in order: 9 newborns (0.05%) had received phototherapy and 7 newborns (0.04%) were born to consanguineous marriages. In addition, 3 newborns (0.02%) had a low birth weight and 1 newborn (0.006%) had a history of fever.CONCLUSION:Screening tests should be performed in all newborns for early detection of hearing loss. Even though frequency of hearing loss is higher in newborns with risk factors, the treatment should be started within 6 months, the latest, and newborns should be referred for rehabilitation and training.

Assessment of cochlear function in children with sickle cell anemia

Background: Sickle cell disease is characterized by vaso-occlusion which leads to impaired blood supply to several organs. The cochlear in particular has been known to be highly sensitive to anoxia which is, in turn, a proven cause of sensorineural hearing loss (SNHL). Early detection of hearing loss is paramount in these patients, as the cochlear ischemic damage is repetitive and progressive. Once the damage is sufficiently enough to cause noticeable hearing loss, the loss is mostly substantial and irreversible. Otoacoustic emission is useful in detecting early cochlear damage. Materials and Methods: Children with sickle cell anemia (SCA) (HbSS) aged between 1 and 12 years diagnosed by hemoglobin electrophoresis and equal number of controls matched (HbAA) matched for age and sex were recruited for the study. All participants underwent a detailed ear, nose, and throat examination and tympanometry. Those with normal middle ear function were further subjected to transient-evoked otoacoustic emissions (TEOAEs) testing. Results: There were 60 patients with SCA (cases) and 60 controls. The age of the participants ranged between 1–12 years with a mean of 6.5 ± 3.74 among the cases and 7.02 ± 3.54 among the controls. The male–female ratio was 0.9:1. Among participants with normal middle ear function, TEOAE was abnormal in 43 (48.8%) ears of the cases and 70 (73.7%) ears of the controls. There was a statistically significant difference in abnormal TEOAEs outcome between cases and the control group (P = 0.002). Conclusion: Children with SCA had a high rate of abnormal cochlear function. Therefore, there is a need for periodic monitoring of cochlear function in these patients so as to detect and treat SNHL early.

Hearing and Tinnitus Evaluation in Music Teachers.

Music is an aesthetic whole consisting of sounds combined according to a certain purpose, method and understanding. Therefore, it also interacts with emotions in listeners. Music sounds are in the range of approximately 20-8000 Hz. This frequency range is within the frequency spectrum of the human cochlea. The aim of this research is to evaluate the hearing thresholds of music teachers and to determine whether they cause tinnitus. This research was conducted in Turgut Özal University Medical Faculty Hospital Audiology and Speech Disorders clinic. A total of 35 people (17 music teachers, 18 control groups) participated in the research. In this research, 17 music teachers (11 females, 6 males) aged 24-39, and 18 volunteers (12 females, 6 males) participated in the control group. After the otoscopic examination of all participants, pure tone audiometry (in the range of 125-16,000 Hz), immitansmetric examination and Distortion Product Otoacoustic Emission (DPOAE) tests were performed. Tinnitus Handicap Inventory (THI) was used in the evaluation of tinnitus. There was no statistically significant difference between the music teachers and the control group in all pure tone hearing threshold averages of 125-16,000 Hz (p>0.05). The Uncomfortable Level (UCL) average of music teachers was 104.12 ± 3.83 dB for the right ear, 108.33 ± 3.83 dB for the control group, 107.78 ± 4.28 dB for the left ear, and 103.53 ± 4.28 for the control group. DPOAE results were found statistically significant at 3000 Hz only for the right and left ears (p=0.036; p=0.015, respectively). Also, for DPOAE test, the control group's OAE values were higher than the music teachers. According to the Tinnitus Handicap Inventory in music teachers, 1st degree tinnitus has emerged. According to the findings obtained, the low UCL value in music teachers compared to the control group suggests the tolerance problem. Continuous exposure to the sound was thought to create a noise effect on the cochlea, and as a result, tinnitus susceptibility appeared in music teaching.

A validation study of auditory function in an aminoglycoside-furosemide ototoxicity mouse model: Auditory brainstem response and distortion product otoacoustic emissions

Sensorineural hearing loss due to ototoxic drugs remains as a conflict as the treatment option with aminoglycosides. Ototoxic mouse model was produced with the administration of ototoxic drugs aminoglycoside kanamycin and loop-diuretic furosemide, thus validation of auditory function of the mouse model is needed to determine the efficacy of the drugs. Kanamycin sulfate 550 mg/kg (VWR life sciences, PA, USA) and furosemide 130 mg/kg (Lasix, Handok, Korea) were administered through subcutaneous and intraperitoneal injection respectively. Auditory brainstem response and distortion otoacoustic emission tests were performed on days 3,5,7,10,14 post administration of the ototoxic drug. Thresholds in response to the stimulus given in the auditory brainstem recordings and distortion otoacoustic emission tests were obtained. The hearing threshold shift to high stimulus intensity was observed post administration of the ototoxic drug. Latency of the ABR peak waves were recorded and analyzed, latency delay was observed as hearing threshold increases. These findings will further support in the application of this animal model in various studies regarding ototoxic hearing loss.

Screening of Hearing in Infants at Risk in a Tertiary Care Centre: A Descriptive Cross- sectional Study

Background: Screening of hearing impairment in children facilitates earlier identification, management and prevention of disability. The objective of this study was to perform a screening of hearing in infants at risk in Tribhuvan University Teaching Hospital.&#x0D; Methods: A descriptive cross-sectional study was done among 228 infants who were at risk of hearing loss. All ‘at risk’ infants born to mothers in Tribhuvan University Teaching Hospital and ‘at risk’ children below one year of age admitted in the pediatric ward and intensive care unit were screened for hearing loss by automated otoacoustic emission (OAE) and automated auditory brainstem reflex (ABR). The results were categorized as pass or refer (fail). The association between hearing loss and the potential risk factors was analyzed.&#x0D; Results: Out of 228 infants screened, 117 (51%) were male and 111 (49%) were female. Seventy (30.7%) failed OAE and 44 (19.3%) failed ABR. Univariate analysis (Pearson Chi-square test) showed that the failure rate for ABR was significantly associated with preterm babies (p = 0.009), low birth weight (p = 0.009), usage of ototoxic drugs (p = 0.03), and intensive care unit stay of more than five days (p = 0.03). Only preterm birth was significantly associated with failed OAE test (p = 0.03).&#x0D; Conclusion: Premature birth (gestational age &lt; 34 weeks) was associated with failure of the ABR and OAE tests. The infants with low birth weight, history of ototoxic drugs, ICU stay more than 5 days were only associated with ABR test failure.

Effects of primary arterial hypertension on cochlear function

Background Hypertension (HT) is one of the most common chronic diseases. The existing literature on HT and hearing contains conflicting results, and no consensus has been reached yet. Objectives This study aimed to investigate cochlear function in hypertensive and normotensive groups. Methods This study was conducted on 34 patients with primary HT and 17 healthy adults. The Cochlear function was assessed with conventional audiometry (0.125–8 kHz), ultra-high frequency audiometry (10–16 kHz), the transient evoked otoacoustic emission (TEOAE) test, and the distortion product otoacoustic emission (DPOAE) test. Results Hearing thresholds at 8, 10, 12.5, 14, and 16 kHz were significantly poorer in the HT group than in the control group (p < .05). There was no significant difference in the mean conventional thresholds between the groups. Compared to the control group, the patient group exhibited statistically significant lower amplitudes of TEOAE and DPOAE. Conclusion This study demonstrated significantly poorer high-frequency hearing and lower otoacoustic emission amplitudes for adults with HT. Impairment in hearing thresholds associated with HT begins at ultra-high frequencies in the cochlea. HT may be a potential risk factor for the development of hearing loss; therefore, individuals with HT should be screened for auditory function.