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Hearing loss is one of the most prevalent genetic disorders in humans. Locus and allelic heterogeneity cause fundamental challenges in hearing loss genetic diagnosis and management of patients and their families. This study examined the genetic profile of patients with prelingual hearing loss who were referred to the Genetic Foundation of Khorasan Razavi spanning over a decade. Deleterious variants in GJB2 were evaluated through Sanger sequencing among 745 non-syndromic hearing loss patients. Furthermore, exome sequencing was applied in 250 patients with negative GJB2 sequencing results and 30 patients with syndromic hearing loss. The findings revealed a relatively low frequency of GJB2 variants among the studied patients. Exome sequencing successfully identified the genetic causes of hearing loss in 70% of the patients. Moreover, variants in 10 genes, namely SLC26A4, MYO15A, TMPRSS3, TMC1, OTOF, CDH23, PJVK, MYO7A, TECTA, and PCDH15, accounted for 66% of the positive exome sequencing findings in this study. At least three prevalent founder alleles in the hearing-impaired population of eastern Iran were identified. This study emphasizes the efficiency of exome sequencing as a powerful tool for determining the etiology of prelingual hearing loss in the eastern Iranian population., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: To determine the prognostic factors in the pediatric cochlear implant (CI) outcome., Materials and Methods: This prospective cohort study was conducted on 289 pediatric cases with prelingual hearing loss who received cochlear implantation. Several possible salient factors have been recorded. Auditory and speech evaluations were performed before CI, as well as 6 and 12 months after surgery, using Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) tests., Results: According to univariate analysis, age at the time of surgery was a statistically significant factor. Neurological problems in the child, history of newborn infectious diseases, history of hearing aid use, proper parental cooperation, and round window approach were all significantly related to better auditory or speech outcomes. On the other hand, good parental cooperation and age (for CAP) and good parental cooperation, age, history of infectious disease, and hearing aids use (for SIR) are the significant factors in the multivariate setting., Conclusion: As evidenced by the obtained results, age, background diseases, history of rehabilitation with hearing aids, and surgical details are essential factors to be taken into account in the case-selection process., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objective: Biological, structural, and acoustical constraints faced by cochlear implant (CI) users can alter the perception of music. Bimodal fitting not only provides bilateral hearing but can also improve auditory skills. This study was conducted to assess the impact of this amplification style on the emotional perception of music among children with hearing loss (HL)., Methods: Twenty-five children with congenital severe to profound HL and unilateral CIs, 20 children with bimodal fitting, and 30 children with normal hearing participated in this study. Their emotional perceptions of music were measured using a method where children indicated happy or sad feelings induced by music by pointing to pictures of faces showing these emotions., Results: Children with bimodal fitting obtained significantly higher mean scores than children with unilateral CIs for both happy and sad music items and in overall test scores (P < .001). Both groups with HL obtained significantly lower scores than children with normal hearing (P < .001)., Conclusions: Bimodal fitting results in a better emotional perception of music compared to unilateral CI. Given the influence of music in neurological and linguistic development and social interactions, it is important to evaluate the possible benefits of bimodal fitting prescriptions for individuals with unilateral CIs., (© The Author(s) 2015.)

Introduction: According to World Health Organization (WHO) 2001 statistics, hearing disorders are the most common congenital disease, and the incidence rate among high-risk newborns is as much as ten times as high as that in healthy neonates. However, 78% of screening test failures are well-baby nursery babies. The Joint Committee on Infants' Hearing (JCIH) has emphasized the importance of early diagnosis and treatment in neonates with hearing impairments in order to preserve their maximum linguistic skills. The aim of our study was to compare the prevalence of hearing loss among babies in the neonatal intensive care unit (NICU) and the rooming-in unit (RIU)., Materials and Methods: Neonates born in three hospitals in Mashhad between 2008 to 2010 were studied prospectively and screened for auditory disorders using the oto acoustic emission (OAE) test at the time of discharge and 3 weeks later. To confirm hearing loss, the auditory steady state response (ASSR) test was used among those participants who failed both OAE tests., Results: Two-thousand and sixty-three neonates from the NICU were screened and compared with a control group consisting of 8,724 neonates from the RIU or the well-baby nursery. At the end of the study, hearing impairment as confirmed by failure in the ASSR test was diagnosed in 31 neonates (26 in the control group [0.30%] and five in the NICU group [1.94%])., Conclusion: In our study, the prevalence of hearing disorders among NICU neonates was 6.5-times greater than that among babies from the RIU or well-baby unit. This observation demonstrates the importance of universal screening programs particularly for high-risk population neonates.

Objective: The purpose of this study was to analyze changes in neural response telemetry (NRT) and electrically evoked stapedial reflex thresholds (ESRT) before and after stylet withdrawal during cochlear implant surgery., Methods: Thirty children (21-92 months old) who were candidates for cochlear implantation took part in this study. In all of them Nucleus Contour Advance was implanted. NRT and ESRT responses were recorded initially with the stylet in and then when the stylet was taken out during the implant procedure. The recordings were performed in the basal, middle, and apical areas of the electrode array., Results: The threshold levels required to obtain NRT and ESRT responses after stylet removal were lower. This decrease was observed in all parts of the cochlea. It was statistically significant in all areas with the exception of the basal ESRT measurements., Conclusion: Withdrawing the stylet results in better NRT and ESRT responses, most probably due to a favorable position change of the electrode array within the scala tympani., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Objective: Preeclampsia is a critical condition that puts both pregnant women and their offspring at risk for multiorgan failure, including inner ear, due to systemic toxemia and vascular events. This study was done to determine the probable prevalence of hearing impairment in children whose mothers had pregnancy-induced hypertension, compared to those born to healthy mothers., Methods and Materials: A cohort study was performed on two groups; the first group was made up of the offspring of preeclamptic women (n = 36) and the second was made up of offspring born to healthy mothers (n = 114). They were matched for sex and age. Other confounding variables that could have influenced the hearing were excluded. Transient evoked otoacoustic emission (TEOAE) and auditory brain response (ABR) tests were performed to screen hearing loss in each group., Results: Failure rates in the first step for cases and controls were 33.33 percent and 12.76%, respectively, which showed a significant difference statistically (P = 0.001). However, the final results of the second TEOAE and ABR between the two groups were not statistically significant (P > 0.05)., Conclusion: Although it does not seem that pregnancy toxemia plays a role in permanent hearing loss in neonates of affected mothers, it might have a transient effect on hearing.

We evaluated the long-term speech intelligibility of young deaf children after cochlear implantation (CI). A prospective study on 47 consecutively implanted deaf children with up to 5 years cochlear implant use was performed. The study was conducted at a pediatric tertiary referral center for CI. All children in the study were deaf prelingually. They each receive implant before the program of auditory verbal therapy. A speech intelligibility rating scale evaluated the spontaneous speech of each child before and at frequent interval for 5 years after implantation. After cochlear implantation, the difference between the speech intelligibility, rating increased significantly each year for 3 years (P < 0.05). For the first year, the average rating remained "prerecognizable words" or "unintelligible speech". After 2 year of implantation the children had intelligible speech if someone concentrates and lip-reads (category 3). At the 4- and 5-year interval, 71.5 and 78% of children had intelligible speech to all listeners (category 5), respectively. So, 5 years after rehabilitation mode and median of speech intelligibility rating was five. Congenital and prelingually deaf children gradually develop intelligible speech that does not plateau 5 years after implantation.