Changes In Hearing Thresholds Research Articles

Circadian vulnerability of cisplatin-induced ototoxicity in the cochlea.

The chemotherapeutic agent cisplatin is renowned for its ototoxic effects. While hair cells in the cochlea are established targets of cisplatin, less is known regarding the afferent synapse, which is an essential component in the faithful temporal transmission of sound. The glutamate aspartate transporter (GLAST) shields the auditory synapse from excessive glutamate release, and its loss of function increases the vulnerability to noise, salicylate, and aminoglycosides. Until now, the involvement of GLAST in cisplatin-mediated ototoxicity remains unknown. Here, we test in mice lacking GLAST the effects of a low-dose cisplatin known not to cause any detectable change in hearing thresholds. When administered at nighttime, a mild hearing loss in GLAST KO mice was found but not at daytime, revealing a potential circadian regulation of the vulnerability to cisplatin-mediated ototoxicity. We show that the auditory synapse of GLAST KO mice is more vulnerable to cisplatin administration during the active phase (nighttime) when compared to WT mice and treatment during the inactive phase (daytime). This effect was not related to the abundance of platinum compounds in the cochlea, rather cisplatin had a dose-dependent impact on cochlear clock rhythms only after treatment at nighttime suggesting that cisplatin can modulate the molecular clock. Our findings suggest that the current protocols of cisplatin administration in humans during daytime may cause a yet undetectable damage to the auditory synapse, more so in already damaged ears, and severely impact auditory sensitivity in cancer survivors.

Do Impedance Changes Correlate With a Delayed Hearing Loss After Hybrid L24 Implantation?

Preservation of residual hearing is one of the main goals in present cochlear implantation surgery. Especially for this purpose, smaller and softer electrode carriers were developed that are to be inserted through the round window membrane to minimize trauma. By using these electrodes and insertion technique, residual hearing can be preserved in a large number of patients. Unfortunately, some of these patients with initially preserved residual hearing after cochlear implantation lose it later on. The reason for this is unknown but it is speculated about a correlation with an increase in impedance, since increased impedance values are linked to intracochlear inflammation and tissue reaction. Our hypothesis for this study design was that an increase in impedance predicts changes in residual hearing under clinical conditions. Data of all adult patients (N = 122) receiving a Hybrid-L24 cochlear implant at our center between 2005 and early 2015 were retrospectively evaluated. Impedance values in Common Ground mode as measured during clinical routine and referring audiological test data (audiometric thresholds under headphones) were collected. Changes between consecutive measurements were calculated for impedance values and hearing thresholds for each patient. Correlations between changes in impedances and acoustic hearing thresholds were calculated. Average values were compared as well as patients with largest impedance changes within the observation period were evaluated separately. Group mean values of impedances were between 5 and 7 kΩ and stable over time with higher values on basal electrode contacts compared with apical contacts. Average hearing thresholds at the time of initial fitting were between 40 to 50 dB (250 Hz) and 90 dB (1 kHz) with a loss of about 10 dB compared with preoperative values. Correlation between impedance changes and threshold changes was found, but too inconsistently to imply a true relationship. When evaluating the 20 patients with the largest impedance changes during the observation period (all >1 kΩ from one appointment to the next one), some patients were found where hearing loss is timely connected and highly correlated with an unusual impedance change. But large impedance changes were also observed without affecting hearing thresholds and hearing loss was found without impedance change. Changes in impedance as measured during clinical routine cannot be taken as an indicator for a late acoustic hearing loss.

Loss of Cochlear Ribbon Synapse Is a Critical Contributor to Chronic Salicylate Sodium Treatment-Induced Tinnitus without Change Hearing Threshold.

Tinnitus is a common auditory disease worldwide; it is estimated that more than 10% of all individuals experience this hearing disorder during their lifetime. Tinnitus is sometimes accompanied by hearing loss. However, hearing loss is not acquired in some other tinnitus generations. In this study, we injected adult rats with salicylate sodium (SS) (200 mg/kg/day for 10 days) and found no significant hearing threshold changes at 2, 4, 8, 12, 14, 16, 20, or 24 kHz (all p > 0.05). Tinnitus was confirmed in the treated rats via Behaviour Testing of Acoustic Startle Response (ASR) and Gap Prepulse Inhibition Test of Acoustic Startle Reflex (GPIAS). A immunostaining study showed that there is significant loss of anti-CtBP2 puncta (a marker of cochlear inner hair cell (HC) ribbon synapses) in treated animals in apical, middle, and basal turns (all p < 0.05). The ABR wave I amplitudes were significantly reduced at 4, 8, 12, 14, 16, and 20 kHz (all p < 0.05). No significant losses of outer HCs, inner HCs, or HC cilia were observed (all p > 0.05). Thus, our study suggests that loss of cochlear inner HC ribbon synapse after SS exposure is a contributor to the development of tinnitus without changing hearing threshold.

Randomized placebo-controlled clinical trial investigating the effect of antioxidants and a vasodilator on overall safety and residual hearing preservation in cochlear implant patients

BackgroundThe standard therapy for patients suffering from sensorineural hearing loss is cochlear implantation. The insertion of the electrode array into the cochlea, with potential mechanical trauma and the presence of this foreign body inside the cochlea, may lead to free radical formation and reduced blood perfusion of the cochlea which can result in a loss of residual hearing. Studies have suggested that a particular combination of the antioxidants vitamins A, C and E as well as the vasodilator magnesium (together: ACEMg) may protect the residual hearing.MethodsThe potential protective effect of ACEMg on residual hearing preservation in cochlear implant (CI) patients was investigated in a single-centre, randomized, placebo-controlled, double-blind phase II clinical trial. CI candidates with some residual hearing in low frequencies receiving MED-EL implants of different FLEX electrode array lengths were treated with ACEMg tablets or placebo respectively 2 days preoperatively and up to 3 months postoperatively. The study objective was to demonstrate that ACEMg is more efficacious than placebo in preserving residual hearing during cochlear implantation by comparing the hearing loss (change in hearing thresholds at 500 Hz from baseline) 3 months after the first fitting between the two treatment groups and to investigate the treatments’ safety.ResultsFifty-one patients were included in the study, which had to be terminated before the recruitment goal was reached because of IMP-resupply mismanagement of one partner. In the intention-to-treat population, 25 patients were treated with ACEMg and 24 patients with placebo. The mean hearing loss at 500 Hz was (± 15.84) 30.21 dB (placebo) or (± 17.56) 26.00 dB (ACEMg) 3 months after the initial fitting. Adjusting the postoperative hearing loss for the baseline residual hearing, planned electrode length and surgeon results in 8.01 dB reduced hearing loss in ACEMg-treated patients compared to placebo-treated ones. The safety analysis revealed that ACEMg was generally well-tolerated with adverse event frequencies below the placebo level.ConclusionThis is the first clinical trial investigating a drug effect on residual hearing in CI patients. These first-in-man data may suggest that a perioperative oral administration of ACEMg is safe and may provide protection of residual hearing in CI patients.Trial registrationEU Clinical Trial Register No. 2012-005002-22. Registered on 6 December 2013. Funding: European Commission FP7-HEALTH-2012-INNOVATION-2.

ASSESSMENT OF HEARING THRESHOLDS IN MEDICAL STUDENTS BASED ON GENDER AND USE OF HEADPHONES.

Introduction: The sounds we are exposed to everyday are usually at a safe level and do not affect our hearing. However, development of latest technology and frequent use of headphones has increased the proximity of sound to the ear. Adolescents and young adults who are commonly exposed to loud music/noise are at a greater risk of developing hearing impairment. Hence the adverse effects of chronic exposure to loud sounds need to be assessed.&#x0D; Objectives: To determine hearing thresholds in students (Males/Females) at various frequencies and the changes in hearing thresholds associated with prolonged exposure (&gt;90mins) to sound.&#x0D; Materials and Methods: The study was conducted in 148 first year MBBS students.&#x0D; Materials used - ALPS Advanced Digital Audiometer AD2100, bone oscillator and headphones.&#x0D; Statistical analysis was done using SPSS version 22.0 with p&lt;0.05 as significant.&#x0D; Results: 1) Males have lower hearing thresholds than females except at higher frequencies where females have equal or better hearing thresholds than males.&#x0D; 2) The mean exposure to headphones was 115.432±92.1348 mins.&#x0D; Subjects with &gt;90mins exposure had better hearing thresholds at lower frequencies but at higher frequencies showed increase in hearing thresholds.&#x0D; Conclusion: Lower hearing thresholds in females at higher frequencies could be evolutionary as females are more sensitive to high pitch sounds like baby’s cry. Prolonged exposure to loud sound damages hair cells at base of cochlea responsible for picking up high frequency sounds.&#x0D; Keywords: Hearing thresholds, noise, adolescents.

Hearing Loss in Patients With Ankylosing Spondylitis: A Systematic Review and Metaanalysis

To determine the prevalence of hearing loss (HL) in patients with ankylosing spondylitis (AS) and to describe frequency-specific hearing threshold changes in this patient population compared to patients without AS. A systematic review querying 4 databases (PubMed, OVID Medline, Scopus, Cochrane) was performed to identify studies evaluating HL in patients with AS. Metaanalysis was performed to identify overall prevalence rate and OR of HL, as well as to compare mean differences in frequency-specific hearing thresholds between patients with and without AS. Our metaanalysis included 14 studies and 1083 patients (598 with AS vs 485 without AS). The pooled prevalence of HL in patients with AS was 42.4% (95% CI 29.2-56.2). Patients with AS had a significantly higher OR of HL than patients without AS (OR 4.65, 95% CI 2.73-7.91). Mean differences in pure-tone hearing thresholds ranged from 0-5 decibels (dB) for frequencies of 0.25-4 kHz, and from 5-15 dB for frequencies of 6-16 kHz. Patients with AS have higher odds of having HL than patients without AS. The AS population also presents with significantly impaired hearing thresholds across all conventional and extended pure-tone frequencies. This may manifest as slight to moderate HL. Results of this systematic review might justify increased attention to audiologic manifestations of patients with AS.

The comparison of changes in hearing thresholds and insertion losses due to occlusion induced by ear impression in sound field assessment

Background and Aim: The methods of deter­mining the amount of sound attenuation by ear mold, earplug or any other foreign body that placed in or out of the ear canal, is divided in subjective and objective. Due to the contradic­tory results in the studies in this field, this study aimed to use more audiometric frequencies con­sidering the strengths and weaknesses of previ­ous studies. Methods: This study was conducted on 30 indi­viduals with normal hearing in the age range of 21-26-year-old. First the impression mold was prepared from both ears. The evaluating real ear unaided response and the real ear occluded res­ponse. In the next step, hearing thresholds were assessed by sound field with a precision of 1 dB, once in both open ear and once in both clo­sed ears. Finally, the insertion loss due to mold placement at each frequency was compared with the amount of behavioral threshold changes at the same frequency. Results: By using paired t-test at frequencies of 400, 500, 800, 1000, 1500, 1600, 2000, 2500, 3000, 4000, 5000, 6000, 6300 and 8000 Hz, the difference in behavioral hearing thresholds with and without molding was greater than the amo­unt of the insertion loss (p &lt; 0.001). Conclusion: The insertion loss due to impre­ssion for behavioral assessment at all of the tes­ted frequencies were more than the attenuation in real ear evaluation (p &lt; 0.001). In this regard, consequently the standard deviation of insertion loss due to impression in behavioral threshold condition was more than real ear measurement. Keywords: Sound field assessment; insertion loss; real ear occluded response; ear impression; probe microphone measurement; real ear measurement

Detailed evaluation of hearing loss (HL) associated with high-dose (HD) carboplatin for salvage treatment of germ cell tumors (GCT).

401 Background: HD carboplatin is an essential part of curative salvage high-dose chemotherapy (HDCT) for GCT. Although ototoxicity is a known side effect of HD carboplatin, data on severity and characteristics of HL in this population are limited. Methods: Eligible patients (pts) received salvage HD carboplatin for GCT at our center from 1993-2017 and had audiograms pre- and post-HDCT. All pts were planned for 3 sequential cycles of HD carboplatin; some had audiograms after each cycle. HL severity was classified by ASHA criteria (slight: 15-24dB; mild: 25-40dB; moderate: 41-55dB; moderately severe: 56-70dB; severe: 71-90dB; profound: &gt;90dB). Change in hearing threshold at each frequency (0.25 – 8 kHz) was analyzed by clinical and treatment variables using the Wilcoxon rank-sum test. The proportion of pts recommended for hearing aids was also recorded. Results: Of 115 pts (median age 31, 77% nonseminoma), 96 received TI-CE and 19 received TI-TIC on a clinical trial (Feldman CGUC 2015). Pts varied by prior cisplatin exposure (77% with ≤4 vs 23% with 5-9 cycles) and number of HD carboplatin cycles (89% had 3, 10% had 2, and 2% had 1). Carboplatin AUC was 21 in 23%, 24 in 75%, and 28 in 3%. Moderate to profound HL was present in 23% pre-HD carboplatin vs 82% post, preferentially at high frequencies (Table). Of 89 pts with normal to mild HL at baseline, 78% developed moderate or worse HL post-HD carboplatin, including 61% with moderately severe or severe HL. Higher AUC (24 vs 21) and number of HD carboplatin cycles were associated with greater HL with HD carboplatin whereas prior cisplatin exposure was not. Due to moderate or severe HL in the vital speech frequency range (2 – 4kHz), 20 (17%) pts were recommended for hearing aids post-HD carboplatin. Conclusions: In the largest series to detail ototoxicity in pts receiving salvage HD carboplatin for GCT, we show HL, particularly at high frequencies, is a major dose-dependent toxicity. Most pts will have at least moderate high frequency HL after HD carboplatin with approximately 1 in 6 recommended for hearing aids. [Table: see text]

Effects of Vibrant Soundbridge on tinnitus accompanied by sensorineural hearing loss.

Tinnitus is a common symptom among patients with hearing loss, and many studies have reported successful tinnitus suppression with hearing devices. Active middle ear implantation of the Vibrant Soundbridge (VSB) is a good alternative to existing hearing devices. This study evaluated the effects of VSB implantation on tinnitus and sought to identify the main audiological factor that affects tinnitus suppression. The study participants were 16 adults who had tinnitus with sensorineural hearing loss, and who underwent VSB implantations. Pure-tone audiometry; word recognition test; tinnitus handicap inventory (THI); and visual analog scale (VAS) assessment of loudness, awareness, and annoyance were performed before and 12 months after surgery. Changes in hearing threshold, word recognition scores (WRS), THI scores, and VAS scores were analyzed. VAS scores for loudness (mean difference: 1.9, 95% CI: 0.6, 3.1), awareness (mean difference: 1.6, 95% CI: 0.4, 2.8), and annoyance (mean difference: 1.7, 95% CI: 0.7, 2.8) showed significant improvements from baseline to 12 months after surgery. In addition, THI scores showed a significant decrease (mean difference: 13.8, 95% CI: 2.9, 24.9). The average hearing threshold level, WRS, and most comfortable level (MCL) also showed significant improvements at 12 months after surgery (mean difference: 17.3, 95% CI: 13.3, 21.3; mean difference: -7.6, 95% CI: -15.1, -0.1; mean difference: 26.3, 95% CI: 22.9, 29.6, respectively). Among the aforementioned factors, changes in MCL were best correlated with those in THI scores (mean difference: 2.55, 95% CI: 0.90, 4.21). A VSB implant is beneficial to subjects with tinnitus accompanied by sensorineural hearing loss. The changes in THI scores best correlated with those in MCL. This improvement may represent a masking effect that contributes to tinnitus suppression in patients with VSB implants.

Intratympanic versus intravenous corticosteroid treatment for sudden sensorineural hearing loss in diabetic patients: proposed study protocol for a prospective, randomized superiority trial

BackgroundDiabetes mellitus is associated with risk of sudden sensorineural hearing loss (SSNHL). Systemic and intratympanic corticosteroids are the two primary treatments for SSNHL in patients with diabetes mellitus. The benefit of intratympanic compared to systemic treatment is the reduced systemic steroid exposure and associated systemic adverse effects. Intratympanic corticosteroid administration may have potential benefits over standard systemic therapies.Methods/designThe proposed study is a prospective, randomized superiority trial. A total of 96 patients (48 in each group) will be randomized into the experimental or control group. Patients in the experimental group will receive four 1-mL doses of 40 mg/mL of methylprednisolone over a 1-week period, with a dose administered every 2 days via tympanic membrane injection into the middle ear. The control group will be administered intravenous methylprednisolone (1 mg/kg/day, maximal dose 60 mg/day) for 5 days. The primary outcome for this study is the change in hearing threshold from the first audiogram to the 30-day follow-up audiogram. Secondary outcome measures will include pure-tone average (PTA) at 90-day follow up, visual analog tinnitus scale, visual analog vertigo scale, visual analog aural fullness scale, fasting blood glucose and 2-h postprandial blood glucose during treatment, and the change in glycosylated hemoglobin (HbA1C) levels. Vital signs and otological physical examination will be performed at each follow-up visit.DiscussionThe efficacy and safety of intratympanic methylprednisolone compared to intravenous methylprednisolone will be investigated in patients with diabetes mellitus and SSNHL. This trial may provide strong evidence for the efficacy and safety of intratympanic corticosteroid treatment and important clinical information for the treatment of patients with diabetes mellitus and SSNHL.Trial registrationChiCTR, ChiCTR1800015954. Registered on 2 May 2018, Retrospectively registered, http://www.chictr.org.cn/showproj.aspx?proj=25326.

Gender variation in age-related hearing loss using pure tone audiometry in city of Bengaluru

Background: Age-related hearing loss is one of the common reasons for disability in our population. There are many studies conducted to find a specific pattern of hearing loss correlating gender and age but have failed to prove a relation. Aim and Objectives: The purpose of this study was to obtain gender related hearing thresholds and to determine the rate of change in pure-tone hearing thresholds between genders. Materials and Methods: Subjects were selected after thorough history to exclude any past history of otorrhoea, usage of ototoxic drugs, head injury, and subjects exposed to noise at work place. Pure tone audiometric evaluation was conducted on 46 male and 54 female volunteers from Bengaluru. Hearing levels for frequencies of 0.25, 0.5. 1, 2, 4, and 8 KHz were determined using ARPHI 500 MK 1 audiometer. Results: The mean hearing ability increases from 17.82 dB at 0.5 KHz to 14.02 dB at 2 KHz in males and from 15.18 dB at 0.25 KHz to 12.50 dB at 1 KHz in females. The average rate of change in threshold was 0.30 dB per decade for males and 0.40 dB per decade for females at 0.25 kHz, increasing/decreasing gradually to 0.62 dB per decade for males and 0.27 dB per decade for females at 8 kHz. Women appear to have faster rate of change in of hearing at the lower frequency of 0.25 KHz. Men had significantly faster rates of threshold increase at 4 and 8 kHz than women. The rate of decline in hearing is faster in males compared to females. Conclusion: Our study has been able to find gender differences in hearing thresholds between genders and found that females have better hearing ability than males. It also found that rate of decline in hearing levels was faster in males compared to females.

Idiopathic Sudden Sensorineural Hearing Loss: Should Otoacoustic Emissions Be Added to the Monitoring Protocol? A Systematic Review

Idiopathic sudden sensorineural hearing loss (ISSNHL) refers to a loss of hearing, most commonly unilateral, that occurs suddenly (≤72 h) with no identifiable cause or etiology. To date, there is no standard protocol to predict prognosis (hearing recovery) for patients with ISSNHL. However, studies have shown that changes in otoacoustic emissions (OAEs) often occur prior to changes in audiometric hearing thresholds. OAEs originate from the electrochemical motility of the outer hair cells (OHC) and reflect the integrity of the inner ear, specifically the cochlear amplifier. Therefore, OAEs may be useful as a prognostic predictive factor in patients with ISSNHL from the initial onset of symptoms through recovery. A systematic review of the literature was undertaken to assess the relationship between pure tone thresholds, OAEs, and subjective hearing improvement and/or recovery. Fourteen studies were identified for inclusion, and they overwhelmingly support the inclusion of OAEs in the protocol to monitor ISSNHL recovery. This finding supports the development of a standard diagnostic protocol that includes OAEs to predict patient hearing outcomes.

Cochlear implants in single-sided deafness – clinical results of a Swiss multicentre study

The aim of this multicentre, prospective, open, nonrandomised clinical trial was to demonstrate the clinical efficiency and outcomes of cochlear implants (CIs) in adult patients with post-lingual single-sided deafness (SSD). A group of five left and five right SSD participants were investigated with various clinical tests and questionnaires before and 12 months after CI activation. Changes in hearing thresholds, speech understanding in noise, sound localisation, tinnitus (Tinnitus Handicap Inventory; THI), subjective hearing ability (Speech, Spatial and Qualities of Hearing Scale; SSQ), and quality of life (WHOQOL-BREF) were assessed. In addition, the pre- and postoperative results of the SSD patients were compared with an age- and gender-matched normal hearing control group. Surgery was uncomplicated in all patients. Two years after implantation, 9 of the 10 patients used their CI regularly for an average of more than 11 hours a day. A significant improvement in speech understanding in noise measured in the sound field using the Oldenburg sentence test could be demonstrated in the two situations in which patients with SSD experience the greatest difficulty: speech from the front and noise at the healthy ear, and speech to the implanted ear and noise from the front. The sound localisation test showed significant improvement of the mean localisation error and the root mean square error after CI activation. Furthermore, a significant reduction of the THI was measured, and the SSQ showed a significant improvement in the subscale speech comprehension and in the subscale spatial hearing. Also, quality of life measured with the WHOQOL-BREF showed a general improvement, which was significant in the global subscale. For this questionnaire, there was no significant difference between the normal-hearing control group and the patients after 12 months of CI use. This study confirmed the clinical benefit of cochlear implantation in patients with SSD. The significant improvement of speech understanding in noise, sound localisation, tinnitus perception, subjective hearing ability, and in particular the improved quality of life support the recommendation that patients with recently acquired SSD should be offered a CI. (Clinical trial registration number on clinicaltrial.gov: NCT01749592).

Endoscopic approach to the round window through posterior tympanotomy for cochlear implantation in children: A study on feasibility

ObjectiveTo demonstrate the feasibility of rigid endoscopy through posterior tympanotomy, which provides both a view of the round window and direction of the scala tympani in children. MethodsAfter a standard mini-invasive surgical approach with postauricular access and transmastoid posterior tympanotomy of 2 mm, a 0°, 1.9 mm diameter and 11 cm long endoscope is positioned in proximity of the upper part of the posterior tympanotomy to obtain a panoramic view of the inferior part of the medial wall of the tympanic cavity. Surgical complications and changes in hearing threshold were analyzed. ResultsEight children were submitted to cochlear implantation with endoscopic assistance through posterior tympanotomy. Complete visualization of the round window niche was possible in every ear. No complications related to the procedure were observed. Preoperative threshold was preserved in 9 of 10 ears. ConclusionsDirect endoscopic view through the posterior tympanotomy allows visualization of the entire round window niche as well as the angle of introduction of the multi-electrode array along the direction of the scala tympani.

Prospective Study of Dietary Patterns and Hearing Threshold Elevation.

We conducted a prospective study of dietary patterns and longitudinal change in audiometric hearing thresholds among 3,135 women (mean age = 59 years) in the Nurses' Health Study II (2012-2018). Diet adherence scores for the Dietary Approaches to Stop Hypertension (DASH) and Alternate Mediterranean (AMED) diets and the Alternate Healthy Eating Index 2010 (AHEI-2010) were calculated using validated food-frequency questionnaires. Baseline and 3-year follow-up hearing sensitivities were assessed by pure-tone audiometry at 19 US sites. We used multivariable-adjusted logistic regression models to examine independent associations between diet adherence scores and risk of ≥5 dB elevation in the pure-tone average (PTA) of low-frequency (LPTA0.5,1,2 kHz), mid-frequency (MPTA3,4 kHz), and high-frequency (HPTA6,8 kHz) hearing thresholds. Higher adherence scores were associated with lower risk of hearing loss. Compared with the lowest quintile of DASH score, the multivariable-adjusted odds ratios for mid-frequency and high-frequency threshold elevation in the highest quintile were 0.71 (95% confidence interval (CI): 0.55, 0.92; P for trend=0.003) and 0.75 (95% CI: 0.59, 0.96; P for trend=0.02); for AMED and AHEI scores, for mid-frequency threshold elevation, they were 0.77 (95% CI: 0.60, 0.99; P for trend=0.02) and 0.72 (95% CI: 0.57, 0.92; P for trend=0.002). Nonsignificant inverse associations were observed for high-frequency threshold elevation. There were no significant associations between adherence scores and low-frequency threshold elevation. Our findings indicate that eating a healthy diet might reduce the risk of acquired hearing loss.

Can Pregnancy Lead to Changes in Hearing Threshold?

This study explores the changes in hearing thresholds in pregnancy. A prospective hospital-based observational study was performed with a total of 69 patients in the age-group of 18 to 40 years. Patients underwent hearing assessment twice during the study period. Conventional pure tone audiometry and impedance audiometry were performed, first during the antepartum period (28-32 weeks of gestational age) and second time during the postpartum period (6 weeks postpartum). Significant difference was seen between the average of air conduction threshold values at speech frequencies when antepartum values were compared with postpartum values. The alterations in hearing sensitivity in pregnant females which improved during the postpartum period can be attributed to pregnancy.

Hearing loss in very preterm infants: should we wait or treat?

SUMMARYThis study investigated hearing threshold changes during the first year of corrected age (CA) in infants admitted in a neonatal intensive care unit (NICU). In 5 years, 239 infants with birth weight (BW) ≤ 1,000 gm and/or gestational age (GA) ≤ 30 weeks were enrolled. Hearing was evaluated by oto-acoustic emission (OAEs) before discharge and auditory brainstem response (ABR) within 3 months of CA. Infants affected by unilateral or bilateral hearing loss were addressed to audiological follow-up until definitive diagnosis (within 6 months of CA). Changes in hearing threshold were also carefully analysed. 207 (86.6%) infants had normal hearing while 32 infants (13.4%) showed hearing loss (HL) at the confirmative ABR evaluation (9 mild, 16 moderate, 4 severe, 3 profound). The latter showed lower GA (27.7 ± 2 vs 28.4 ± 1.2; p = 0.0061) and BW (950 ± 390 vs 1,119 ± 326 gm; p = 0.0085). At final evaluation, 15 infants (47%) recovered a normal hearing. HL was confirmed in 17 patients. Among these, 3 infants were addressed to audiological follow-up (one case of mild unilateral hearing loss (UHL) and two with moderate UHL), while in 14 cases (44%) with bilateral sensory neural hearing loss (SNHL) (7 moderate, 4 severe, 3 profound) hearing aids were prescribed. They showed significantly lower GA and longer hospital stay in the NICU in comparison with infants without indication for audiological habilitation (18 infants) (GA 26.2 ± 2.2 weeks vs 28.4 ± 2.4; p = 0.01; NICU stay 132 ± 67 vs 59 ± 7; p = 0.0002). Definitive diagnosis was obtained at 5.9 ± 1.3 months of CA. Our study confirms the importance of audiological surveillance in preterm newborns. Hearing thresholds of preterm infants with hearing loss can change during the first year of CA and we observed normalisation in 47% of our patients. Most vulnerable to permanent SNHL were very preterm infants with a longer NICU stay, while a shorter stay represents a favourable prognostic factor for hearing improvement.

Changes in Hearing Threshold and Tinnitus Severity after Stapes Surgery: Which Is More Important to the Patient’s Quality of Life?

Background: Stapes surgery is a common method of treatment of otosclerosis, and its effectiveness is reported based on audiometric hearing thresholds. Audiometric tests do not gauge the impact of tinnitus severity and auditory function on quality of life (QOL) after stapes surgery. Objective: To measure self-assessed QOL in otosclerosis patients after stapedotomy in terms of three major factors: change in audiometric hearing threshold, subjective hearing benefit, and tinnitus severity. Method: This prospective clinical study included 191 patients who underwent stapedotomy between April and October 2017 due to otosclerosis. All patients were tested by pure tone audiometry and filled in a questionnaire before surgery and 6 months afterwards. Subjective hearing was assessed with the Abbreviated Profile for Hearing Aid Benefit (APHAB); tinnitus severity was established using the Tinnitus Functional Index (TFI), and the QOL was measured by the Glasgow Benefit Inventory (GBI). Results: Statistical analysis showed that the average GBI total score (mean = 33.7; SD = 23.7) was statistically significantly higher than zero (t = 19.7; p < 0.001). Based on a regression model, all the three variables studied – audiometric hearing thresholds change, APHAB change, and TFI change – had a significant effect on QOL after stapedotomy. Interestingly, the highest beta value (b = 0.040; p < 0.001) was for TFI change, implying that TFI change had the greatest effect on QOL. Conclusion: Although the improvement of QOL after stapes surgery undoubtedly depended on improvement in both audiometric and self-reported hearing, the reduction of tinnitus severity had the greatest impact on increase in QOL.

Intracochlear Electrocochleography: Response Patterns During Cochlear Implantation and Hearing Preservation

Electrocochleography (ECochG) obtained through a cochlear implant (CI) is increasingly being tested as an intraoperative monitor during implantation with the goal of reducing surgical trauma. Reducing trauma should aid in preserving residual hearing and improve speech perception overall. The purpose of this study was to characterize intracochlear ECochG responses throughout insertion in a range of array types and, when applicable, relate these measures to hearing preservation. The ECochG signal in cochlear implant subjects is complex, consisting of hair cell and neural generators with differing distributions depending on the etiology and history of hearing loss. Consequently, a focus was to observe and characterize response changes as an electrode advances. In 36 human subjects, responses to 90 dB nHL tone bursts were recorded both at the round window (RW) and then through the apical contact of the CI as the array advanced into the cochlea. The specific setup used a sterile clip in the surgical field, attached to the ground of the implant with a software-controlled short to the apical contact. The end of the clip was then connected to standard audiometric recording equipment. The stimuli were 500 Hz tone bursts at 90 dB nHL. Audiometry for cases with intended hearing preservation (12/36 subjects) was correlated with intraoperative recordings. Successful intracochlear recordings were obtained in 28 subjects. For the eight unsuccessful cases, the clip introduced excessive line noise, which saturated the amplifier. Among the successful subjects, the initial intracochlear response was a median 5.8 dB larger than the response at the RW. Throughout insertion, modiolar arrays showed median response drops after stylet removal while in lateral wall arrays the maximal median response magnitude was typically at the deepest insertion depth. Four main patterns of response magnitude were seen: increases > 5 dB (12/28), steady responses within 5 dB (4/28), drops > 5 dB (from the initial response) at shallow insertion depths (< 15 mm deep, 7/28), or drops > 5 dB occurring at deeper depths (5/28). Hearing preservation, defined as < 80 dB threshold at 250 Hz, was successful in 9/12 subjects. In these subjects, an intracochlear loss of response magnitude afforded a prediction model with poor sensitivity and specificity, which improved when phase, latency, and proportion of neural components was considered. The change in hearing thresholds across cases was significantly correlated with various measures of the absolute magnitudes of response, including RW response, starting response, maximal response, and final responses (p's < 0.05, minimum of 0.0001 for the maximal response, r's > 0.57, maximum of 0.80 for the maximal response). Monitoring the cochlea with intracochlear ECochG during cochlear implantation is feasible, and patterns of response vary by device type. Changes in magnitude alone did not account for hearing preservation rates, but considerations of phase, latency, and neural contribution can help to interpret the changes seen and improve sensitivity and specificity. The correlation between the absolute magnitude obtained either before or during insertion of the ECochG and the hearing threshold changes suggest that cochlear health, which varies by subject, plays an important role.

Calculatuon and assessment noise induced hearing loss excess risk in group of population

Introduction. Prevention of occupation hearing loss should be based on mathematical models and computational methods to predict changes in hearing thresholds (HT) with age and under the action of noise on the hearing organ. There is an urgent need for quantitative methods to determine the health risk of exposure to noise above 80 dBA.The aim of the studywas to determine the group excessive risk of hearing loss (ERHL) under the action of noise using the model of the third edition of ISO 1999.Materials and methods. Developed technology for the determination of the HT model, the third edition of ISO 1999, depending on the gender, age, length of service and experienced noise exposure on the basis of the related sett lement tables MSExcell for population percentiles 1 to 99% in 1% step.Results.With the use of the developed technology, the initial data were determined and the main indicators of the group risk of hearing loss at the levels of criteria for the diagnosis of sensorineural hearing loss (SNT) were calculated. Th eir dependences on age, length of service and noise level are calculated.Conclusions: Th e developed technology allows us to calculate the probable hearing thresholds of the quantile of the population exposed to and unaff ected by noise and the magnitude of the group excess risk.