Profound Hearing Impairment Research Articles

A novel CLRN2 variant: expanding the mutation spectrum and its critical role in isolated hearing impairment.

Biallelic variants in the CLRN2 gene have been reported to cause autosomal recessive profound hearing impairment in humans. CLRN2 belongs to the clarin gene family that encodes a tetraspan protein that contains a cytosolic N-terminus, multiple helical transmembrane domains, and an endoplasmic reticulum membrane retention signal, TKGH, in the C-terminus. The encoded protein may be important in development and homeostasis of the inner ear and retina. Here, we present a consanguineous family suffering from autosomal recessive non-syndromic profound hearing impairment (HI). We employed state of the art Whole exome sequencing (WES), Sanger sequencing followed by routine bioinformatics filtration steps and homology modeling to elucidate the effect of mutation at the protein level. ES followed by Sanger sequencing revealed a novel homozygous nonsense variant in the CLRN2 gene [c.414C > A; p.Cys138*]. Furthermore, insilico protein modeling of the wildtype and mutated version of the CLRN2 protein revealed large-scale changes that predict to compromise the routine normal function of the protein. Our finding further extends the mutations spectrum of CLRN2 gene and confirms its important role in hearing homeostasis and with developmental disorder in humans.

The impact of hearing loss and cochlear implantation on the quality of life in children

BackgroundThis study evaluates the Quality of Life (QoL) in children with moderate to profound hearing impairments using cochlear implants (CIs), compared to those with normal hearing. It explores the impacts of hearing loss and the effectiveness of CIs in pediatric populations. MethodsConducted at a tertiary care academic center, this cross-sectional study included children aged 13–18. Participants were divided into three groups: normal hearing, yet to be treated moderate or worse hearing loss (uHL), and CI users. Demographic data were collected, and the QoL was assessed using the Hearing Environments and Reflection of Quality of Life (HEAR-QL) questionnaire, with scores across various subdomains compared. ResultsOf the 79 children meeting the inclusion criteria, 38 % had normal hearing, 29 % had at least moderate HL, and 33 % were CI users. Statistically significant differences in HEAR-QL scores were found among the groups. The normal hearing group reported the highest scores. In the subdomain of hearing circumstances and academic performance, CI users showed no significant difference from the normal hearing group, unlike those with untreated uHL who scored lower. However, in social interaction and emotional well-being subdomains, CI users' scores were lower than those of the normal hearing group but similar to the uHL group. ConclusionChildren with CIs show comparable QoL in auditory capabilities to their normal hearing peers but experience significant challenges in psychosocial and emotional areas. This indicates that while CIs can improve hearing-related quality of life, they do not fully address the psychosocial impacts of hearing loss.

Evaluating the long-term outcomes from cochlear implant surgery for children with single and multiple additional needs

Cochlear implant surgery is a cornerstone in the treatment of severe to profound hearing impairment. Despite comprising a significant proportion of the deaf population, children with additional needs have only been included for cochlear implant candidacy in recent years. This paper aims to evaluate the long-term progress of children with additional needs post-implantation compared to children without additional and assess how this trend changes over time. MethodsThis is a longitudinal cohort study comparing the outcomes between children with no additional needs, children with a single additional need, and children with multiple additional needs. The five outcome measures used assessed both auditory perception and expressive and receptive language. For each outcome measure, subjects were assessed pre implant and one-, three-, and five-years post-implant. ResultsThe total cohort consisted of 334 subjects: 181 with no additional needs, 116 with a single additional need, and 37 with multiple additional needs. The results showed that children with additional needs performed significantly poorer in all outcome measures compared to those without additional needs, with a greater negative effect associated with multiple additional needs. In auditory perception, both additional needs groups increased in rate of progress over time, in contrast to language capabilities for which the rate plateaued at a significantly lower level than children without additional needs. Once again, both of these effects were greater for the multiple additional needs group. ConclusionIt is clear that there is reduced progress in children with additional needs compared to those without, and that the number of additional needs present is an important factor in this. Despite initial delays, it seems as though children with additional needs may catch up over time in auditory perception scores, however for language skills, this cohort may achieve limited scores even as time progresses. It is important to investigate this further to gauge the factors that are causing this discrepancy to see if any can be limited to maximise outcome.

Research status and progress of bilateral cochlear implantation

With the development of social economic and technology, Cochlear Implantation has became an effective therapy for patients who suffered from severe or profound hearing impairment. In the meantime, patients' demands for sound and auditory quality are also increasing. In terms of speech recognition, localization, and auditory quality, bilateral hearing is closer to the auditory experience of normal individuals, so bilateral cochlear implantation（BCI） emerged as the times require. In this article, we will introduce the status and progress of bimodal regarding to the following aspects: the brief history, the advantages of BCI, different methods for BCI, and the problems encountered in BCI.

Biallelic variants in TMIE and PDE6B genes mimic Usher syndrome

In the case of consanguineous families, comorbidity cannot be ruled out. Here, we reported a child of eleven years-old who presented profound congenital hearing impairment and progressive visual defect who was suspected to have Usher syndrome. We searched for mutations in Usher syndrome genes but we failed to detect any. We then performed whole exome sequencing to identify the causality of their phenotype. Interestingly, we found two homozygous missense variants, p.(Arg84Trp) in TMIE, responsible for deafness and p.(His337Arg) in PDE6B, responsible for retinitis pigmentosa. The combination of both variants mimics Usher syndrome. This article highlights the importance of genetics in avoiding clinical misdiagnosis, which is important for genetic counseling and in the perspective of gene therapy.

A murine model for the del(GJB6-D13S1830) deletion recapitulating the phenotype of human DFNB1 hearing impairment: generation and functional and histopathological study

Inherited hearing impairment is a remarkably heterogeneous monogenic condition, involving hundreds of genes, most of them with very small (< 1%) epidemiological contributions. The exception is GJB2, the gene encoding connexin-26 and underlying DFNB1, which is the most frequent type of autosomal recessive non-syndromic hearing impairment (ARNSHI) in most populations (up to 40% of ARNSHI cases). DFNB1 is caused by different types of pathogenic variants in GJB2, but also by large deletions that keep the gene intact but remove an upstream regulatory element that is essential for its expression. Such large deletions, found in most populations, behave as complete loss-of-function variants, usually associated with a profound hearing impairment. By using CRISPR-Cas9 genetic edition, we have generated a murine model (Dfnb1em274) that reproduces the most frequent of those deletions, del(GJB6-D13S1830). Dfnb1em274 homozygous mice are viable, bypassing the embryonic lethality of the Gjb2 knockout, and present a phenotype of profound hearing loss (> 90 dB SPL) that correlates with specific structural abnormalities in the cochlea. We show that Gjb2 expression is nearly abolished and its protein product, Cx26, is nearly absent all throughout the cochlea, unlike previous conditional knockouts in which Gjb2 ablation was not obtained in all cell types. The Dfnb1em274 model recapitulates the clinical presentation of patients harbouring the del(GJB6-D13S1830) variant and thus it is a valuable tool to study the pathological mechanisms of DFNB1 and to assay therapies for this most frequent type of human ARNSHI.

Temporal, spectral and amplitude characteristics of the Greek fricative /s/ in hearing-impaired and normal-hearing speech

ABSTRACT Fricatives, and especially sibilants, are very frequently misarticulated by speakers with hearing loss. Misarticulations can result in phonemic contrast weakening or loss, compromising intelligibility. The present study focuses on the examination of acoustic characteristics of the Greek alveolar fricative /s/, an articulatorily demanding sound, produced by young adult speakers with profound hearing impairment and with normal hearing. An array of variables was examined using mixed-effects and random forest models aiming to assess the effectiveness of various measures in differentiating hearing-impaired and normal-hearing /s/ production. Significant differences were found in spectral and amplitude measures, but not in temporal measures. In hearing-impaired speech, spectral slope and RMS amplitude had significantly lower values, indicating a more distributed spectrum, suggestive of decreased flow velocity through the fricative constriction. Also, a trend for concentration of energy at lower frequencies was observed suggesting more posterior fricative articulation than normal. Moreover, measures capturing the variation of frequency and amplitude over time revealed different patterns of sibilance development across time than normal, denoting the production of a less well-formed or less sibilant /s/ by speakers with hearing impairment. The investigation of contextual effects on /s/ in hearing-impaired speech showed increased spectral variance, negative skewness and lower kurtosis in the labial (rounded) context /u/ in relation to the nonlabial contexts /i/ and /a/, indicating a more diffuse, less compact spectrum with concentration at high frequencies. Findings are discussed in relation to previous literature on fricative production by speakers with hearing impairment and normal hearing in Greek and other languages.

A comparative study of learning outcomes for hearing-impaired foundation phase learners

Background: Two intervention approaches are implemented in South Africa to alleviate the deleterious consequences of congenital or early onset hearing impairment on language acquisition and subsequent poor learning outcomes.Aim: This study investigated the learning outcomes of foundation phase learners with severe to profound hearing impairment who received Listening and Spoken Language – South Africa (LSL-SA) (adapted Auditory Verbal Therapy) therapy compared to those who received Traditional Speech-Language Therapy (TSLT).Setting: The study was conducted at four early intervention (EI) schools for children with hearing impairment across three provinces in South Africa.Methods: Data were collected through record reviews of their Speech-Language Therapy Outcomes and South African National Department of Basic Education academic report cards. Data were analysed using quantitative statistics.Results: Findings demonstrated that children with hearing impairment enrolled in LSL-SA outperformed those enrolled in TSLT in achieving age-equivalent language outcomes. A higher percentage of learners enrolled in LSL-SA achieved meritorious to outstanding learning outcomes. While a comparable number of learners progressed to mainstream schooling, children with hearing impairment enrolled in LSL-SA are enrolled for a shorter duration until discharge than those enrolled in TSLT. This is an important finding, particularly in low-middle income countries (LMICs).Conclusion: Listening and Spoken Language – South Africa graduates achieved superior learning outcomes dependent on language attainment, providing contextually relevant evidence supporting the effectiveness of the LSL-SA EI approach.Contribution: These context-specific outcomes stress the obligation to upscale and fast-track EI services. Implications for investment in LSL-SA are proposed through collaboration between families, educators, and early interventionists.

Histological Reaction in the Round Window Membrane after Cochlear Implant Insertion in Nonhuman Primates

Introduction: The primary objective of this article was to determine if any histological alterations occur in the round window (RW) and adjacent anatomical structures of an animal model with normal hearing when a cochlear implant (CI) electrode array is inserted. Furthermore, this article aims to relate these histological alterations to the auditory changes generated. Methods: Cochlear implantation was performed, following the principles of minimally traumatic surgery (MTS), in 15 ears of nonhuman primates (Macaca fascicularis) (Mf) with normal hearing. Auditory brainstem-evoked potentials (ABR) using clicks and tones were used prior to surgery and during a 6-month follow-up period. Histological evaluation was carried out, analyzing the position of the electrode array with respect to the round window membrane (RWM), its percentage of occupation and integrity, the presence of intracochlear damage, and the tissue reaction provoked, the latter of which was quantified in the temporal bones. Results: Surgery was performed on all 15 ears without relevant incidences. Regarding histology, the electrode array in the RW of all ears presented a lateral position with respect to the modiolus. No lesions affecting the integrity of the RW were observed. The mean value of the array’s occupation in the RW was 25%. Tissue reaction, in the form of fibrosis, was observed in all ears and more intensely in the trans-RWM and post-RWM areas. In all ears, the electrodes remained on the scala tympani. No profound hearing impairment was recorded in any ear, being the mean loss of 25.4 dB when comparing presurgical thresholds with those collected 6 months after implantation in ABR click and 24.4 dB in ABR tone burst. Conclusions: The animal model and Hybrid L-14 (HL14) electrode array were optimal for implementing a surgical technique similar to that routinely performed on humans. Mild histological alterations were observed in the round window membrane and adjacent anatomical structures from the insertion of a cochlear implant electrode array. Following the minimally invasive technique, levels of hearing preservation were satisfactory, reaching a pre-post difference of 25.4 dB in the ABR click and 24.4 dB for a high-frequency tone burst. Complete hearing impairment was not observed in either ear. Correlation between the severity of histological alterations and hearing changes recorded in the ABR studies was observed.

Cochlear implantation compliance among minorities at high risk for hearing impairment following universal newborn hearing screening.

The universal newborn hearing screening (UNHS) allows for early detection of hearing impairment (HI). The goal of this current study was to evaluate the impact of cultural background involving consanguineous marriage on newborn HI diagnosed using UNHS, and compliance with hearing rehabilitation. This is a retrospective cohort study that included all children born at a single tertiary medical center between 2011 and 2017 who did not pass the UNHS (oto-acoustic emission and auditory brainstem response), and were diagnosed with HI. The study group included children from consanguineous marriage cultural background which were compared to a control group-all other children. Data were retrieved from the computerized medical charts and included epidemiological, audiological, and pregnancy/delivery-related data, and known risk factors for congenital HI. A total of 238 (196 study and 42 control) neonates were diagnosed with HI. Family history of HI was significantly more prevalent in the study group in mild-severe and profound HI subgroups (p = 0.03 and 0.01, respectively). Study group demonstrated lower rates of cochlear implantation (CI) compliance (p = 0.079), performed at a significantly older age (23 months (IQR 17-36.5) vs. 16 (IQR 12-26) months, p = 0.021). When recommended, bilateral CI compliance was significantly lower in the study group (94.1 vs.48.9%, p < 0.001). UNHS allows for early HI detection among minority populations at higher risk for CI, yet compliance rates remain lower compared with control. Familiarity of families with the importance of early detection and HI risk may result in higher compliance rates for cochlear implantation. Health providers should aim to improve education and communication with this unique group of patients and consider health promotion programs.

Robot-Assisted and Manual Cochlear Implantation: An Intra-Individual Study of Speech Recognition.

Cochlear implantation (CI) allows rehabilitation for patients with severe to profound hearing impairment. Although the use of a robotic assistant provides technical assistance to the surgeon, the assessment of the impact of its use on auditory outcomes remains uncertain. We aim to compare the hearing results of patients who underwent bilateral cochlear implantation; one side was performed with manual insertion and the other side with robot-assisted insertion. The electrode array intrascalar positioning and the surgery duration were also studied. This retrospective intra-individual study involved 10 patients who underwent bilateral cochlear implantation. The study included two infants and eight adults. The unique composition of this cohort enabled us to utilize each patient as their own control. Regarding speech disyllabic recognition, pure tone average, ECAP, ratio of array translocation, basilar membrane rupture, and percentage of translocated electrodes, there was no difference between manual and robot-assisted CI groups. This study is the first to compare intra-individual hearing performance after cochlear implantation, either manually or robot-assisted. The number of patients and the time delay between manual and robotic implantation may have led to a lack of power, but there was no apparent difference in hearing performance between manual and robotic implantation.

Agnieszka Duniewska: Understanding literary texts by students with hearing impairment. Oficyna Wydawnicza Impuls, Krakw 2021

Nowadays, reading ability is one of the basic competences that enable an individual to function in the world. Agnieszka Duewska's publication, Understanding literary texts by students with hearing impairment presents, in a multi-faceted way, issues related to language and its role in cognition, as well as shows the difficulties faced by students with profound and severe hearing impairment during the process of understanding the read text. Often, a low level of language competences contributes to many negative consequences, which include not only marginalization, but also less opportunities for development and life satisfaction. This book, in the light of the research conducted so far, presents a new perspective, therefore it is worth getting acquainted with it more closely.

Auditory Steady-State Response and Hearing Impairment in Survivors of Childhood Bacterial Meningitis in Luanda, Angola.

Survivors of childhood bacterial meningitis (BM) often develop hearing impairment (HI). In low- and middle-income countries (LMICs), BM continues to be a significant cause of hearing disability. We assessed hearing among BM survivors using auditory steady-state responses (ASSR), providing frequency-specific estimated audiograms, and examined whether ASSR would provide a greater understanding of BM-induced HI. Survivors from two prospective BM trials (ISRCTN62824827; NCT01540838) from Luanda Children's Hospital were examined in a follow-up visit with a median duration of 26 months after BM. The hearing of 50 BM survivors and 19 control children was evaluated using ASSR and auditory brainstem response (ABR) after interview and neurological and otorhinolaryngological examinations. The median age of survivors was 80 (IQR 86) months. We diagnosed HI (better ear hearing ≥ 26 dB) in 9/50 (18%) children. Five of the fifty survivors (10%) and 14/100 ears (14%) had profound HI (>80 dB). Severe-to-profound HI affected all frequencies steadily, affecting only the ears of BM survivors (18/100 vs. 0/38, p = 0.003). When looking only at the severely or profoundly affected ears, young age, low Glascow coma score, pneumococcal aetiology, and ataxia were associated with a worse hearing outcome.

Early cochlear implantation in prelingual profound hearing loss in Italy, analyzed by means of a social media survey.

To assess newborn hearing screening (NHS) impact on timing of cochlear implant (CI) surgery of patients with prelingual bilateral profound hearing impairment (BPHI), in order to evaluate whether the NHS ultimately serves the needs of the target population in Italy. An online questionnaire was created to survey subjects affected by prelingual BPHL born between 1990 and 2018. Questions focused on age at BPHI diagnosis, first and second CI surgery (if performed), and the region in which the surgery was performed. The survey was distributed to potential participants via social media communities used by hearing impaired people or their family members for sharing advice and offering support. Responses were analyzed using descriptive statistics. Among the 318 respondents who completed the questionnaire, 276 (87%) reported having chosen CI surgery, 2/3 of them bilaterally. In the vast majority (97%) of cases the CI is used on a daily basis. Most of the people residing in the center (65%) and southern Italy (71%) had to move from their region of residence to perform the surgery. Late CI surgery was associated with failure to perform NHS (p = 0.007), birth before 2011 (p = 0.009), definitive diagnosis of BPHI after 6months of life (p = 0.002), and progressive hearing impairment (p < 0.001). The worldwide scientific approval of the NHS as the current best opportunity for early diagnosis and CI treatment for prelingual BPHI is confirmed by what patients and families reported via the online questionnaire used for this study. In recent years, early bilateral cochlear implantation has become increasingly available in Italy, but late diagnosis, progressive hearing loss, failure to perform the NHS and lack of follow-up are still open questions. A large proportion of families had to move from the region of residence to have their child undergo CI surgery, revealing inequalities in terms of geographical disparities. Social media has proved to be a valuable, fast and inexpensive tool for gathering information on the effectiveness of health prevention programs, involving a large sample of individuals in a short amount of time.

Analysis of molecular genetics and clinical characteristics of 3 children with Waardenburg syndrome

Objective:To analyze the molecular genetics and clinical characteristics of 3 children with syndromic deafness were analyzed to clarify their causative genes and genetic characteristics. Methods:The medical records of 3 children and their parents were collected and analyzed, including physical examination, hearing evaluation, temporal bone CT, and cranial MRI. Whole-exome sequencing（WES） was used to screen for pathogenic gene variants, and Sanger sequencing was used to verify the candidate positive variants in the probands and their parents. Results:All 3 patients were female with normal intelligence. Patient 1 and 3 had a family history of deafness, which conformed to the pattern of autosomal dominant inheritance. All three patients had bilateral profound sensorineural hearing impairment with bright-blue sclera. Other phenotypes included hypertelorism（patient 1）, multiple dyschromatosis（patient 2）, and yellowish hair（patient 2）, blepharoptosis（patient 3）. Patient 3 had bilateral vestibular enlargement, internal auditory canal enlargement, and bilateral inner ear malformations. Mother of patient 1 had only left mild hearing impairment; mother of patient 3 had bilateral hearing impairment with unilateral bright-blue sclera and yellowish hair. WES detected heterozygous variants, PAX3 c.811C>T, MITF c.632T>C, and SOX10 c.1359_1360 insGCCCCACA, in patient 1, 2, and 3, respectively. The variants in patient 1 and 3 were inherited from their mothers who had hearing impairment, and MITFvariant in patient 2 may be a spontaneous variation. The final diagnoses were that patient 1 with Waardenburg syndrome type 1（WS1）, and the mother of patient 1, patient 2, patient 3, and the mother of patient 3 with WS2. Conclusion:WS is a syndromic deafness, and the main clinical features include autosomal dominant inheritance and scleral pigment abnormalities. However, the findings of this study show that there is still phenotypic heterogeneity in WS even caused by the same gene variant, so it depends on genetic tests to confirm the diagnosis; The gene variant of patient 1 and 2 was never been reported in other patients, which expands the pathogenic variant spectrum of WS.

Patient perspectives on the need for improved hearing rehabilitation: A qualitative survey study of German cochlear implant users.

The electrical cochlear implant (eCI) partially restores hearing in individuals affected by profound hearing impairment (HI) or deafness. However, the limited resolution of sound frequency coding with eCIs limits hearing in daily situations such as group conversations. Current research promises future improvements in hearing restoration which may involve gene therapy and optical stimulation of the auditory nerve, using optogenetics. Prior to the potential clinical translation of these technologies, it is critical that patients are engaged in order to align future research agendas and technological advancements with their needs. Here, we performed a survey study with hearing impaired, using an eCI as a means of hearing rehabilitation. We distributed a questionnaire to 180 adult patients from the University Medical Center Göttingen's Department of Otolaryngology who were actively using an eCI for 6 months or more during the time of the survey period. Questions revolved around patients needs, and willingness to accept hypothetical risks or drawbacks associated with an optical CI (oCI). Eighty-one participants responded to the questionnaire; 68% were greater than 60 years of age and 26% had bilateral eCIs. Participants expressed a need for improving the performance beyond that experienced with their current eCI. Primarily, they desired improved speech comprehension in background noise, greater ability to appreciate music, and more natural sound impression. They expressed a willingness for engaging with new technologies for improved hearing restoration. Notably, participants were least concerned about hypothetically receiving a gene therapy necessary for the oCI implant; but expressed greater reluctance to hypothetically receiving an implant that had yet to be evaluated in a human clinical trial. This work provides a preliminary step in engaging patients in the development of a new technology that has the potential to address the limitations of electrical hearing rehabilitation.

Cochlear Implantation in Children with Congenital Inner Ear Malformations

AbstractBackground: Cochlear Implantation has proven beneficial in patients with profound congenital hearing impairments. Performing cochlear implantation in patients with inner ear malformation has always been a matter of dispute as congenital deaf ears may have anatomical malformations and difficulties during operation, it is important to focus on problems and complications that may face the surgeon who is performing this operation.Objective: Evaluate the problems and surgical difficulties encountered in patients with congenital inner ear malformation, who underwent cochlear implantation.Patients and methods: A series of 21 pediatric cochlear implant (CI) patients with known inner ear malformations determined on computed tomography (CT) of the temporal bone who underwent cochlear implantation in the department of otolaryngology in Hospital Martyr Ghazi Al-Hariri and AL-Yarmouk Teaching Hospital, Baghdad, Iraq, during the period from January 2018 to January 2021 were the subjects of the study to determine intraoperative adverse effects of these anomalies regarding electrode array insertion depths, predisposition to cerebrospinal fluid (CSF) leak through the cochleostomy, and associated facial nerve anomalies that can create access problems for scala tympani.Results: The most common inner ear anomalies were wide vestibular aqueduct (15) patients with percentage of (71.4%), incomplete partitions (5) patients with percentage of (23.8%), and common cavity (1) patient with percentage of (4.8%). CSF leak, the most common was CSF ooze (11) patients with percentage of (52.4%), CSF gusher seen in (6) patients (28.6%), and no CSF leak in (4) patients (19%). Facial nerve anomalies, only one case has abnormal position (more superficial and not injured) with a percentage of (4.8%), while in 20 patients (95.2%) no anomaly was detected. Electrode insertion depth, full insertion was achieved in (17) patients with percentage of (81%), while incomplete insertion was occurred in (4) patients (19%).Conclusion: Cochlear implant can be successfully and safely done in patients with selected congenital inner ear anomalies. Surgery can be challenging in certain cases of gusher and facial nerve abnormalities, but proper radiology and good surgical technique will help avoid complications. Keywords: Cochlear Implantation, Congenital inner ear malformation, facial nerve anomalies.

Comprehensive Etiologic Analyses in Pediatric Cochlear Implantees and the Clinical Implications.

Cochlear implantation is the treatment of choice for children with profound sensorineural hearing impairment (SNHI), yet the outcomes of cochlear implants (CI) vary significantly across individuals. To investigate the CI outcomes in pediatric patients with SNHI due to various etiologies, we prospectively recruited children who underwent CI surgery at two tertiary referral CI centers from 2010 to 2021. All patients underwent comprehensive history taking, next generation sequencing (NGS)-based genetic examinations, and imaging studies. The CI outcomes were evaluated using Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) scores. Of the 160 pediatric cochlear implantees (76 females and 84 males) included in this study, comprehensive etiological work-up helped achieve clinical diagnoses in 83.1% (133/160) of the patients, with genetic factors being the leading cause (61.3%). Imaging studies identified certain findings in 31 additional patients (19.3%). Four patients (2.5%) were identified with congenital cytomegalovirus infection (cCMV), and 27 patients (16.9%) remained with unknown etiologies. Pathogenic variants in the four predominant non-syndromic SNHI genes (i.e., SLC26A4, GJB2, MYO15A, and OTOF) were associated with favorable CI outcomes (Chi-square test, p = 0.023), whereas cochlear nerve deficiency (CND) on imaging studies was associated with unfavorable CI outcomes (Chi-square test, p < 0.001). Our results demonstrated a clear correlation between the etiologies and CI outcomes, underscoring the importance of thorough etiological work-up preoperatively in pediatric CI candidates.

Is there an unmet medical need for improved hearing restoration?

Hearing impairment, the most prevalent sensory deficit, affects more than 466 million people worldwide (WHO). We presently lack causative treatment for the most common form, sensorineural hearing impairment; hearing aids and cochlear implants (CI) remain the only means of hearing restoration. We engaged with CI users to learn about their expectations and their willingness to collaborate with health care professionals on establishing novel therapies. We summarize upcoming CI innovations, gene therapies, and regenerative approaches and evaluate the chances for clinical translation of these novel strategies. We conclude that there remains an unmet medical need for improving hearing restoration and that we are likely to witness the clinical translation of gene therapy and major CI innovations within this decade.

Risk factors for hearing impairment in infants and toddlers in the Gaza governorates: a case-control study

BackgroundThe risk factors for congenital or early-onset hearing loss vary across countries. This study aimed to explore the risk factors for hearing impairment in children younger than 3 years in Gaza governorates to inform preventive strategies. MethodsThis case-control study started in February, 2017, and ended in July, 2018. Ethical approval was obtained from the Helsinki Committee in Palestine, a national committee established in 1986 that reviews all proposals for heath research, and whose approval is a requirement before any health research in Palestine. Data were collected through face-to-face household interviews. Cases were defined as children diagnosed with moderate, severe, or profound sensorineural hearing impairment within the first 3 years of life (n=169), whereas controls were children who had been screened and found to have unimpaired hearing (n=169). Cases and controls were randomly selected through a systematic sampling approach from the screening lists of the Atfaluna Society for Deaf Children, a registered Palestinian non-governmental organisation that has been working in the field of deaf education and allied services since 1992 and that regularly leads hearing screening campaign for neonates and children younger than 5 years in primary health centres over all Gaza governorates. SPSS version 21 was used for data entry and logistic regression analysis with the chi-square test, odds ratio, and t test. FindingsMaternal unemployment was more prevalent in cases than in controls (p=0·025). Having a family history and consanguinity were more prevalent in cases than in controls (p=0·001 for both). Taking folic acid during the preconception period (p=0·007) and iron supplements during pregnancy (p=0·002) were associated with a lower prevalence of hearing loss. The proportion of mothers of cases who were registered as having received antenatal care during the first trimester was lower for cases than for controls (odds ratio 0·341 [95% CI 0·181–0·640]; p=0·002). Prematurity (p=0·006), low birthweight (p<0·0001), and admission to a neonatal intensive care unit (p=0·002) were strongly associated with hearing impairments. The study also showed that children with recurrent otitis media were at a greater risk of hearing impairment (p<0·0001), as were children who had been exposed to sporadic loud noises, such as nearby bombing, or continuous loud noise at home, such as from nearby factories. (p=0·01). InterpretationThe study concluded that hearing impairment among children younger than 3 years is associated with a wide array of socioeconomic, health, and environmental vulnerabilities. A health promotion programme should be established to address consanguinity, prematurity prevention, and timely and appropriate preconception and antenatal care, alongside universal screening for all children, particularly those at risk as identified in this study. FundingNone.