Total Hearing Loss Research Articles

Association of the protective effect of telmisartan on hearing loss among patients with hypertension.

Hearing loss, affecting a significant portion of the global population, is prevented with peroxisome proliferator-activated receptor γ agonism. Understanding potential protective treatments is crucial for public health. We examine the effect of telmisartan, an antihypertensive drug and partial peroxisome proliferator-activated receptor γ agonist, on hearing loss in patients with hypertension. This retrospective cohort analysis used data from the OMOP Common Data Model database, encompassing information from three tertiary institutions in South Korea. The study included a substantial sample size of 860,103 people diagnosed with hypertension. The study included individuals who had been medically diagnosed with hypertension and had been prescribed antihypertensive drugs, including telmisartan. The study design was established to evaluate the comparative effects of telmisartan and other hypertension medications on hearing loss. We used propensity score matching (PSM) to create a balanced cohort, reducing potential biases between the telmisartan and non-telmisartan groups. From the initial 860,103 patients with hypertension, a propensity score matched cohort was derived from 20,010 patients, with 2,193 in the telmisartan group. After PSM, lower incidence of total hearing loss was observed in the telmisartan group compared to the non-telmisartan group during the 3-year follow-up (0.5% vs. 1.5%, log-rank p = 0.005). In subgroup analysis, this study showed consistent results that lower incidence of total hearing loss was higher in the telmisartan group than in the non-telmisartan group. Telmisartan was associated with reducing certain types of hearing loss in patients with hypertension. Further research is needed to confirm these findings and understand the mechanisms.

Electric Auditory Brainstem Response Audiometry in Cochlear Implants: New Recording Paradigm.

(1) Background: Cochlear implants (CIs) are widely applied to recover audition for patients with severe degrees of or total hearing loss. Electrical stimulation using the electrically evoked ABR (E-ABR) can be recorded in CI recipients through the device. This work was designed to study E-ABR recorded individually from different channels located at the apical, middle, and basal cochlear regions in comparison to their simultaneous separated or adjacent combined recordings. (2) Methods: This study included 17 children fitted with unilateral cochlear implants. All children were subjected to impedance measurement, electrical compound action potentials (ECAP), and E-ABR recording of three channels located at the apical, middle, and basal cochlear regions. This was followed by simultaneous E-ABR recording of the three "separated" channels in comparison to E-ABR recording from three adjacent channels located at the middle cochlear region. (3) Results: Similar E-ABR latencies and amplitudes were found using either individual or simultaneously separated or adjacent combined recording. However, the mean amplitude measures of E-ABR for combined adjacent channels showed a positive correlation with the applied current level. (4) Conclusions: Combined E-ABR recording from adjacent channels is a faster and more reliable technique that can be used effectively without compromising the results of the recorded E-ABR.

Condylar Osteochondroma: A Rare Case Report.

Osteochondroma (OC) is an uncommon reason for the mandibular condyle to grow excessively. Usually unilateral, it can impact the entire mandible, the condyle and ramus, or just the condyle. It is a bony projection covered in cartilage that protrudes from the damaged bone's exterior. Condylar OC are more prevalent as a result of endochondral ossification-related development. The most notable characteristic is the gradual asymmetry of the face over time. Clinical symptoms of the patient include pain, asymmetry, malocclusion, partial or total hearing loss, trismus, and hypomobility of the TMJ. We report a case of 40-year-old male patient complaining of reduced mouth opening since last 10 years. Clinical examination revealed gross facial asymmetry, hard swelling over right TMJ, jaw deviation towards left side, restricted mouth opening of 3mm and deranged occlusion. An irregular radiopaque mass was seen over the right condylar region in OPG. A large, hyperdense mass that obliterated the sigmoid notch and extended medially to the right condyle was visible on CT scans. Using a pre-auricular Alkayat-Bramley technique, the mass was surgically removed. Occlusal corrections and jaw physiotherapy were then administered. On follow up, deviation was corrected and adequate mouth opening was achieved.

Early detection of stroke at the sudden sensorineural hearing loss stage.

Sudden sensorineural hearing loss (SSNHL) can be a prodromal symptom of ischemic stroke, especially posterior circulation strokes in the anterior inferior cerebellar artery (AICA) area. Early diagnosis and optimal treatment for vascular SSNHL provide an opportunity to prevent more extensive area infarction. The objective of our research was to find clues that suggest stroke at the stage of isolated sudden hearing loss. We retrospectively investigated the medical records of patients who received an initial diagnosis of sudden sensorineural hearing loss upon admission from January 2017 to December 2022 at Capital Medical University Affiliated Beijing Tiantan Hospital. Among these patients, 30 individuals who developed acute ischemic stroke during their hospital stay were enrolled as the case group. To create a control group, we matched individuals from the nonstroke idiopathic SSNHL patients to the case group in terms of age (±3 years old) at a ratio of 1:4. We collected the clinical characteristics, pure tone hearing threshold test results, and imaging information for all patients included in the study. Three models were constructed to simulate different clinical situations and to identify vascular sudden sensorineural hearing loss (SSNHL). The results revealed that patients with SSNHL who had three or more stroke risk factors, bilateral hearing loss, moderately severe to total hearing loss, and any intracranial large artery stenosis and occlusion (≥50%) were at a higher risk of developing ischemic stroke during hospitalization. Consistent with previous studies, the presence of vertigo at onset also played a significant role in the early detection of upcoming stroke. Clinicians should be alert to SSNHL patients with bilateral hearing loss, moderately severe to total hearing loss and other aforementioned features. Early pure tone audiometric hearing assessment and vascular assessment are necessary for high-risk patients with SSNHL.

Diabetes mellitus type 1(DM-1) in a child with usher syndrome

Usher Syndrome is a rare genetic (autosomal recessive) disorder that characterized by partial or total hearing loss caused by defective inner ear and vision loss caused by retinitis pigmentosa which worsens by time. We report on a 9 year-old child who was diagnosed by genetic testing via whole exome sequencing (WES) with Usher Syndrome. At the age of two years and three months, the patient developed type 1 Diabetes Mellitus (DM-1). The aim of this article is to provide a comprehensive review of Usher Syndrome. The postulated association of Usher Syndrome and diabetes mellitus type 1 pathogenesis is also highlighted.

Comparison of Click and Level-Specific (LS) CE Chirp-Stimulated Auditory Brainstem Responses in Adults with Hearing Loss.

Background The CE-Chirp stimulus used in the ABR was developed to compensate for the cochlear wave delay. As a version of broadband CE-Chirp stimulus, the use of level-specific (LS) CE-Chirp stimuli, which are created with varying delay models suitable for the intensity levels at which the sound is transmitted, is becoming increasingly common. Purpose The aim of this study was to compare click auditory brainstem responses (ABRs) with LS CE-Chirp ABR thresholds in adults with sensorineural hearing loss. Research Design The research is a cross-sectional-analytical research. Study Sample Twenty-two adult patients (n = 44 ears) with bilateral sensorineural hearing loss were included in the study. Data Collection and Analysis Pure Tone Audiometry (PTA), click ABR and LS CE-Chirp ABR tests were performed on adult (13 male, 9 female) (42.86± 14.50 years) patients with bilateral sensorineural hearing loss. Click ABR and LS CE-Chirp ABR thresholds were compared in terms of proximity to behavioral hearing thresholds of 2 kHz, 4 kHz, and 2-4 kHz averages. Results: Both types of ABR stimuli were able to identify with total hearing loss (n = 6). A statistically significant difference was found between LS CE-Chirp ABR thresholds (53.81±20.28 dB nHL) and click ABR thresholds (58.81±19.11 dB nHL) in the other ears (n = 38) with hearing loss (p=0.00). When both ears were evaluated together and the right and left ears were evaluated separately, no difference was found between LS CE-Chirp ABR thresholds and 4 kHz behavioral hearing thresholds (p: 0.66, p:0.80, p: 0.69, respectively). Conclusion: We determined that in adults with hearing loss, the LS CE-Chirp provides ABR thresholds closer to the behavioral hearing thresholds of 2 kHz, 4 kHz compared to the click stimulus. Notably, there was no difference between LS CE-Chirp ABR thresholds and the 4 kHz behavioral hearing thresholds. We concluded that the LS CE-Chirp stimulus can be used effectively in the estimation of behavioral hearing thresholds in adults with hearing loss Keywords: Auditory Brainstem Response, Hearing loss, Click, Level specific CE-Chirp.

Impedance spectroscopy of enlarged cochlear implant stimulation electrodes – FEM simulations considering the perilymph

Abstract Cochlear implants are hearing prostheses for patients with severe to total hearing loss but intact auditory nerve. An external speech processor captures sound from the environment, which is subsequently converted into electrical signals and transmitted to an electrode array in the patient’s inner ear. The metallic stimulation electrodes of the electrode array electrically stimulate the spiral ganglion cells of the auditory nerve. The functionality of cochlear implants strongly depends on the possible maximum current stimulating the spiral ganglion cells, which can be affected by, e.g., cell growth around the stimulation electrodes. This in turn decreases the stimulation efficiency leading to decreased hearing. Cell growth, implant position and other changes in the surrounding medium are reflected in a change of the impedance of the stimulation electrodes. The impedance measurement of the stimulation electrodes is already implemented in all common cochlear implant systems to check functionality of the stimulation electrodes after implantation, but the frequency spectrum is normally not analyzed. Although this method can detect cell growth on the stimulation electrodes, it faces limitations when other interfering effects, such as changes in the perilymph and implant position, influence the impedance. This work shows impedance spectroscopic measurements using enlarged cochlear implant models to electrically analyze the surrounding medium, the perilymph, to understand changes in electrode impedance and to later monitor the stimulation efficiency of cochlear implants and to identify possible reasons for decreased hearing ability by impedance spectroscopy. In addition, we use FEM simulations to numerically model the influence of the perilymph composition on the impedance measurement. As shown by a final validation, this model can serve as a basis for an extended simulation model including implant position and cell growth monitoring to predict hearing deterioration in cochlear implant patients. In this context, this work serves as a basis for the development of a holistic prediction model and considers in the first step exclusively the influence of the perilymph composition on the impedance between two stimulation electrodes.

Parental Competence as a Teacher in the Auditory Development of Children with Cochlear Implants.

The number of children with partial or total hearing loss is increasing every day, and most of them are undergoing cochlear implant surgery. The paper aims to assess the teaching competence of parents of children with cochlear implants. The study took one year (2022) in 1 [Almaty, Kazakhstan] kindergarten and 1 specialized school. Twenty-four parents of children (mean age 3.5 ± 0.5 years) and 20 parents of children of primary school age (10.0 ± 0.5 years) who underwent surgery at the age of 1-2 and 6-9 years were included in the study. A minimal number of parents had a high level of competence; sufficient competence was noticed among the two times larger number of parents; however, most of the parents had insufficient competence. The indicators of children were as follows: 3 children had a high level of listening perception; twice as many of them had a sufficient level; the same number had an insufficient level. There were more children with a low level, 3 times more than with a high level. A high level of pedagogical competence of parents correlated with a high level of children's auditory verbal abilities (on the scale of auditory ability integration). There was also a direct relationship with the level of speech development (on the scale of speech use) for children who had the surgery a year earlier. The obtained data can apply to the educational process for children with cochlear implants to improve their auditory and speech skills as quickly as possible. The involvement of parents in the education and rehabilitation of children with cochlear implants is crucial for the successful adaptation and development of the child. Parents can become irreplaceable partners of specialists and educational institutions, providing their children with optimal support and assistance on their way to the development of auditory and communication skills. To enhance parental competence in the area of auditory development of children with cochlear implants, it is recommended to participate in specialized educational programs designed for parents, offered by professionals and organizations. Additionally, actively engaging with educational resources, online materials, and informational communities is beneficial for acquiring up-to-date knowledge and receiving support from other parents, specialists, and experts.

Hearing aid through skin sensory for profound deaf people

An individual with profound deafness or total hearing loss has a hearing threshold of 80dB or more. The ineffectiveness of hearing aids, surging costs and complex surgeries for cochlear implants have discouraged many to opt for these types of treatments. Hence, this research aims to provide an alternative hearing aid that stimulates “hearing” through the skin sensory, which is more affordable and accessible for the profoundly deaf or total hearing loss community. We have developed four initial vibrating transducers with single spectrum, which are strapped to a belt. The transducers pick up audible sounds through a microphone, amplifies the sound to a high-level signal, stimulating a vibration pattern on the human skin sensory. The belt was tested on 30 random people who identified as normal, partial, and profoundly deaf. When the belt was strapped to the individual’s waist, audible sound was played (stimulus) and the individual was asked whether he/she can feel a stimulation or vibration on their skin, and if so, state the sound source direction. Based on the test, all individuals were able to feel the vibrating stimulation on their skin, and they were also able to state the directions accurately. The various vibrating pattern that stimulates the human sensory system for the profoundly deaf can be learned over time, which could serve as useful information. However, interpreting and identifying the different types of vibrating pattern perceived through the skin remains a huge challenge for profoundly deaf people. As hearing through skin sensory is a very new area of research, there are very limited research articles published in this field. Thus far, this is the first study to evaluate the method of audio spectrum to develop hearing aid through skin sensory.

Case report: Compound heterozygous nonsense PCDH15 variant and a novel deep-intronic variant in a Chinese child with profound hearing loss.

Usher syndrome is a condition characterized by partial or total hearing loss and progressive pigmentary retinopathy. Usher syndrome type 1F is caused by biallelic loss-of-function variants in Protocadherin 15 (PCDH15), which encodes the PCDH15 protein that plays an important role in the morphogenesis and cohesion of stereocilium bundles and retinal photoreceptor cell maintenance and function. We report a child with bilateral nonsyndromic sensorineural hearing loss who received an inconclusive diagnosis based on clinical gene panel testing, which identified a paternal heterozygous nonsense variant (NM_033056.4: c.733C>T, p.R245*) in PCDH15. This variant has been described as a founder variant in the Ashkenazi Jewish population. A novel deep-intronic variant (NM_033056.4: c.705+3767_705+3768del) inherited from the patient's mother was identified by trio-based whole-genome sequencing (WGS). A minigene splicing assay revealed that c.705+3767_705+3768del results in aberrant retention of 50 or 68 bp of intron 7. Our genetic test results provided precise genetic counseling and prenatal diagnosis for this family, and our findings highlight the power of WGS for detecting deep-intronic variants in patients with undiagnosed rare diseases. Additionally, this case expands the variant spectrum of the PCDH15 gene and our results support the extremely low carrier frequency of c.733C>T in the Chinese population.

Knowledge and attitudes of deaf persons towards safe abortion services in Ghana.

Deafness refers to partial or total loss of hearing, which, if not appropriately accommodated, may interfere with day-to-day living experiences. Deaf people encountered challenges in their efforts to access essential services, such as health care. While some attention has been given to general access to reproductive health services, less research has focused on the experiences of deaf women and girls when accessing safe abortion services. With unsafe abortion being a major cause of maternal deaths among women in developing countries, this study attempted to explore the perception of deaf women and girls in Ghana towards safe abortion services. The main aim of this study was to understand the perception and awareness safe abortion services among deaf women and girls in Ghana. In doing this, the contributors towards unsafe abortion practices among deaf women and girls were gathered. Penchansky and Thomas' accessibility to health care theory availability, accessibility, accommodation/adequacy, affordability, and acceptability guides this study. A semi-structured interview guide based on components of the theory was used for data collection from 60 deaf persons. The components of the theory were used as a priori themes that guided the data analysis. The results showed challenges associated with the indicators of health access. For instance, in terms of availability, it was revealed that deaf women had little knowledge about existing laws on safe abortion in Ghana. In relation to acceptability, deaf women were highly opposed to abortion for cultural and religious reasons. However, there was consensus that safe abortion could be conducted under certain conditions. The results of the study have implications for policymaking aimed at attaining equitable access to reproductive health care for deaf women. The need for policymakers to expedite public education and incorporate the needs of deaf women in reproductive health policies, as well as other study implications, are discussed.

Symptom: Vertigo After Labyrinthectomy

Symptom: Vertigo After Labyrinthectomy

Analysis of the vestibular aqueduct development on the risk for suffering from idiopathic sudden sensorineural hearing loss

ObjectiveLarge vestibular aqueduct syndrome (LVAS) is one of the etiology of hearing loss. Clinically, we observed that the VA size of patients with idiopathic sudden sensorineural hearing loss (ISSNHL) did not meet the diagnostic criteria of VA enlargement, but there were individual variations. Through this study, we want to understand the VA development and explore its risk for suffering from ISSNHL. Methods74 patients with ISSNHL were retrospectively reviewed in our department from June 2018 to September 2021. Meanwhile, 57 people with no ear diseases were randomly selected as the control group. All their clinical information were systematically collected. The axial thin-slice CT images of temporal bone were used to observe and measure the VA in ISSNHL and controls. ISSNHL were classified as different types and grades according to pure tone audiometry and the degree of hearing loss, respectively. Logistic regression analysis was adopted to evaluate the risk factors of different types and grades of ISSNHL. ResultsThe operculum morphology could be funnel-shaped, tubular and invisible, but they had no statistical difference in the morbidity of ISSNHL. The operculum width of the affected sides in the case group was significantly wider than that of the matched sides in the control group (0.84±0.35mm vs 0.68±0.34mm, p=0.009), but the midpoint width had no statistical difference (p=0.447). The operculum width was an independent risk factor for the total hearing loss type (p=0.036, OR=4.49, 95% CI=1.10-18.29), moderate (p=0.013, OR=17.62, 95% CI=1.82-170.95) and profound (p=0.031, OR=4.50, 95% CI=1.14-17.67) grade of ISSNHL. Hypertension was an independent risk factor for the severe grade (p=0.004, OR=12.44, 95% CI=2.19-70.64) of ISSNHL. Both the operculum width (p=0.048, OR=7.14, 95% CI=1.02-50.26) and hypertension (p=0.014, OR=6.73, 95% CI=1.46-30.97) were the risk factors for the flat type of ISSNHL. The midpoint width of the VA, gender, age, diabetes mellitus, hyperlipidemia, and plasma fibrinogen concentration had no significant effect on the risk for suffering from ISSNHL. ConclusionThe development of the VA operculum is a risk factor for some types and grades of ISSNHL. Hypertension remained a risk factor for ISSNHL.

Neonatal Hearing Screening and Prevalence of Hearing Impairment in the Time Period of COVID-19 Epidemic in the North of Iran

Background and Aim: COVID-19 is an acute respiratory disease, caused by a coronavirus named SARS-CoV-2. Previous reports suggest an association between COVID-19 infection and Hearing Loss (HL). We have investigated the Universal Newborn Hearing Screening (UNHS) results in the time period of COVID-19 epidemic in Guilan Province, north of Iran. Methods: We analyzed UNHS results from10 major obstetrics hospitals from 20th Mar 2020 to 19th Mar 2021, and compared the total UNHS positive/“refer” and total neonatal HL reports with the same time periods of recent three years. The prevalence of risk factors for HL were analyzed during the same period. Results: The total number of childbirth was decreased significantly from 27735 birth cases in Mar 2017-2018 to 18216 births in Mar 2020-2021 (p<0.001), but the total “refer” rate was significantly increased from 63.0 per 1,000 births in Mar 2019-2020 to 79.8 in Mar 2020-2021 (OR=1.29, 95% CI: 1.19-1.39, p<0.001), and also increased from 74.7 per 1,000 births in Mar 2017-2020 to 79.8 in Mar 2020-2021 (OR=1.07, 95% CI: 1.01-1.14, p=0.020). The HL rate increased from 10.3 per 10,000 births in Mar 2019-2020 and from 11.4 per 10,000 births in Mar 2017-2020 to 18.7 in Mar 2020-2021 (OR=1.81 and 1.63, 95% CI: 1.06-3.09 and 1.10-2.44, p=0.028 and 0.015, respectively). The prevalence of preterm birth (p=0.039) and neonatal intensive care unit stay (p=0.016) was increased significantly during Mar 2020-2021. Conclusion: The chance of “refer” results and neonatal HL, found in the UNHS program, increased during the COVID-19 epidemic in comparison to the past years. Keywords: Newborn; hearing screening; hearing loss; COVID-19

Application for speech assistance of people with hearing disability

Worldwide, there are many people with hearing impairments. Depending on its severity, hearing impairment can be solved using a more or less performant hearing device, according to one’s needs, but in the case of a total loss of hearing, these devices are rather expensive and not affordable for everyone. With these situations in mind, we developed a simple application, named Talky, which can be used to assist people with hearing disabilities, mostly total hearing loss, in order to facilitate the communication process with others. Talky is simple to use and may be useful for people who have difficulty speaking.

Combined effects of multiple metals on hearing loss: A Bayesian kernel machine regression approach

BackgroundExposure to heavy elements is considered one of the risks of hearing loss. The combined effect of multiple metals on different hearing losses has not been extensively studied. MethodsThis study deals with the association between different metals (Ba, Cd, Co, Cs, Mo, Pb, Mn, Sn, Sb, Tl, W) and hearing loss in the 2013–2018 National Health and Nutrition Examination Survey (NHANES). Associations were estimated by a generalized linear regression model (GLM) adjusting for age, gender, race/ethnicity, educational level, marital status, drinking status, hypertension, diabetes, smoking status, noise exposure, body mass index, and income-poverty ratio. The joint effects of mixed exposure were assessed by weighted quantile sum (WQS) model and Bayesian kernel machine regression (BKMR). The effect of multiple metals on speech-frequency hearing loss (SFHL) and high-frequency hearing loss (HFHL) was further calculated. The odds ratio (OR) indicates the risk of every metal exposure. ResultsA total of 2205 adult participants were enrolled from NHANES. Cd, Pb, Sb and Sn had significant effects on total hearing loss. The WQS model found that mixed exposure to heavy elements was significantly positively associated with total hearing loss (OR: 1.136; 95% CI: 1.031, 1.253) after adjusting for various covariates. The ORs of mixed exposure in the SFHL and HFHL groups were 1.066 (95% CI: 0.994, 1.143) and 1.102 (95% CI: 1.013, 1.199), respectively. BKMR found a significant positive association between multiple metals and hearing loss. The results showed that there may be potential interactions between Cd, Pb and other metals. ConclusionsMultiple metals have joint effects on hearing loss in the United States. The findings provide practitioners with important scientific evidence for possible interventions.

3D Ti3C2Tx MXene-Matrigel with Electroacoustic Stimulation to Promote the Growth of Spiral Ganglion Neurons.

Cochlear implantation has become the most effective treatment method for patients with profound and total hearing loss. However, its therapeutic efficacy is dependent on the number and normal physiological function of cochlear implant-targeted spiral ganglion neurons (SGNs). Electrical stimulation can be used as an effective cue to regulate the morphology and function of excitatory cells. Therefore, it is important to develop an efficient cochlear implant electroacoustic stimulation (EAS) system to study the behavior of SGNs. In this work, we present an electrical stimulation system constructed by combining a cochlear implant and a conductive Ti3C2Tx MXene-matrigel hydrogel. SGNs were cultured in the Ti3C2Tx MXene-matrigel hydrogel and exposed to electrical stimulation transduced by the cochlear implant. It was demonstrated that low-frequency stimulation promoted the growth cone development and neurite outgrowth of SGNs as well as signal transmission between cells. This work may have potential value for the clinical application of the Ti3C2Tx MXene hydrogel to optimize the postoperative listening effect of cochlear implantation and benefit people with sensorineural hearing loss.

Assessment of the correlation between residual hearing and audiologic outcomes after cochlear implantation in patients with cochlear nerve deficiency.

ObjectiveThis study aimed to assess the correlation between residual hearing and audiologic outcomes after cochlear implant (CI) surgery in patients with cochlear nerve deficiency (CND).MethodsThis retrospective study included 57 patients with CND who underwent CI surgery. Patients were divided into four groups according to hearing level (80–95, 95–110, 110–120, and >120 dB) and three groups according to residual hearing (entire spectrum hearing, partial spectrum hearing, and no spectrum hearing) based on the measured response at each frequency. Auditory performance (categorical auditory performance [CAP], Infant–Toddler Meaningful Auditory Integration Scale [IT‐MAIS]) and speech perception (speech intelligibility rating [SIR] and meaningful use of speech scale [MUSS]) were assessed before and 2 years after the surgery.ResultsForty‐seven (82.5%) patients had complete or total hearing loss (≥95 dB) and 17 (29.8%) had no spectrum hearing before CI surgery. Twenty‐nine (50.9%) patients did not exhibit residual hearing at 4 kHz. All patients demonstrated an improvement in auditory performance and speech perception: the CAP score in the 80–95 dB group was significantly higher than that in the 110–120 and >120 dB groups, and the entire spectrum hearing group showed significantly higher CAP, SIR, and IT‐MAIS scores than the partial spectrum hearing group and significantly higher CAP, SIR, IT‐MAIS, and MUSS scores than the no spectrum hearing group.ConclusionFor patients with CND, residual hearing, especially high‐frequency residual hearing, was poor and postoperative audiologic outcomes were significantly associated with the range of residual hearing.Level of Evidence4

Association of weight change across adulthood with hearing loss: A retrospective cohort study.

We aimed to investigate the relationship of weight change across adulthood with the risk of hearing loss. The data from National Health and Nutrition Examination Surveys. Cox proportional hazards models were applied to explore the association between weight change and risk of hearing loss. Kaplan-Meier method was used to plot the survival curves associated with weight change patterns. Compared with participants who remained at normal weight, those with stable obese participants had increased risks of total hearing loss across adulthood, with hazard ratios of 1.24 (95% confidence intervals 1.11-1.38) from age 25 years to baseline, 1.09 (1.001-1.18) from 10 years before baseline to baseline, and 1.23 (1.10-1.37) from age 25 years to 10 years before baseline. Moving the obese to non-obese weight change pattern from middle to late adulthood was not significantly associated with an increased risk of total hearing loss (1.04, 0.91-1.19) and high-frequency hearing loss (1.02, 0.90-1.17), whereas changing from non-obese to obese body mass index over this period was associated with total hearing loss risk (1.20, 1.11-1.29), and speech- and high-frequency hearing loss (1.21, 1.07-1.36; 1.18, 1.09-1.28). Those moving from the non-obese to obese category between young and middle adulthood had a 16% (1.16, 1.02-1.33) higher risk of speech-frequency hearing loss. Stable obesity and weight gain across adulthood are both associated with increased risks of hearing loss. Our findings imply that maintaining normal weight across adulthood is of great importance for preventing hearing loss in later life.

Preclinical acoustic efficiency evaluation of bionic ear

Objective. To study the major acoustic properties of the prototype of bionic ear developed in order to confirm its functional performance.
 Materials and methods. Acoustic properties of the bionic ear were measured using Random Phase MultiSine signal in a test bench, which simulated the implant-emitter-osseous tissue-inner ear system. The resulting pulse response was converted to the target characteristics: FR and group lag. Experiments were carried out for -6dB signal level, 10 times for each of the methods used.
 Results. Microtia is a congenital auricular hypoplasia or aplasia (anotia) which often involves impairment or total loss of hearing. One way to rehabilitate this type of patients is to use bone-conducting apparatuses (bone anchored hearing aids), which allow to compensate for the functional component but not to restore facial aesthetics. This paper deals with major acoustic properties of the prototype bionic ear we have previously developed, in order to confirm its functional performance for clinical use. Our analysis of acoustic characteristics of the bionic ear system showed the frequency response was uniform enough in extended voice frequency range (100 to 10000 Hz). The experimental research demonstrated that operating time of the prototype bionic ear to battery depletion is 10 h 26 min with 25 % amplification, 10 h 05 min with 50 % amplification, 9 h 48 min with 75 % amplification.
 Thus, the acoustic characteristics of the vibratory emitter were determined, which confirmed that the bionic artificial ear was eligible for clinical testing.
 Conclusions. Major frequency response of the vibratory emitter was measured, and confirmed that preclinical studies were successful and the bionic ear was eligible for clinical testing.