Application Effect of Unilateral Cochlear Implantation Combined with Contralateral Hearing Aids on the Hearing and Speech Rehabilitation in Prelingual Deafness Children

Objective. The purpose of the study was to investigate the application effect of unilateral cochlear implantation combined with contralateral hearing aids on the hearing and speech rehabilitation in prelingual deafness children. Methods. In this study, a total of 78 children with severe or extremely severe sensorineural prelingual deafness admitted to our hospital from January 2015 to December 2017 were selected and divided into control group (n=39) and experimental group (n=39), according to the random number table. Among them, the children patients in the control group received dominant training after unilateral cochlear implantation, while the children patients in the experimental group received cochlear implantation combined with contralateral hearing aids; after that, the hearing and speech rehabilitation outcomes of the prelingual deafness children in both groups were compared and analyzed. Results. There were no statistically significant differences in the auditory thresholds of the children patients undergoing cochlear implantation between the two groups, while the auditory thresholds of contralateral ears of the children patients in the experimental group were significantly lower than those in the control group. The recognition rates of the initials, finals, tones and disyllables of the children patients in the experimental group were significantly higher than those in the control group, and the CPA and SIR scores of the children patients in the experimental group were significantly higher than those in the control group, with statistical significance (P < 0.05). Conclusions. Unilateral cochlear implantation combined with contralateral hearing aids can promote the hearing and speech rehabilitation in prelingual deafness children, with better clinical effect than the single unilateral cochlear implantation, and cochlear implantation have no interference in the work of contralateral hearing aids; therefore, this joint treatment method is worthy of wide application and promotion.

Otoferlin Is Required for Proper Synapse Maturation and for Maintenance of Inner and Outer Hair Cells in Mouse Models for DFNB9

Deficiency of otoferlin causes profound prelingual deafness in humans and animal models. Here, we closely analyzed developmental deficits and degenerative mechanisms in Otof knock-out (Otof–/–) mice over the course of 48 weeks. We found otoferlin to be required for proper synapse development in the immature rodent cochlea: In absence of otoferlin, synaptic pruning was delayed, and postsynaptic boutons appeared enlarged at 2 weeks of age. At postnatal day 14 (P14), we found on average ∼15 synapses per inner hair cell (IHC) in Otof–/– cochleae as well as in wild-type controls. Further on, the number of synapses in Otof–/– IHCs was reduced to ∼7 at 8 weeks of age and to ∼6 at 48 weeks of age. In the same period, the number of spiral ganglion neurons (SGNs) declined in Otof–/– animals. Importantly, we found an age-progressive loss of IHCs to an overall number of 75% of wildtype IHCs. The IHC loss more prominently but not exclusively affected the basal aspects of the cochlea. For outer hair cells (OHCs), we observed slightly accelerated age-dependent degeneration from base to apex. This was associated with a progressive decay in DPOAE amplitudes for high frequency stimuli, which could first be observed at the age of 24 weeks in Otof–/– mice. Our data will help to plan and predict the outcome of a gene therapy applied at various ages of DFNB9 patients.

Prospective cohort study reveals MMP-9, a neuroplasticity regulator, as a prediction marker of cochlear implantation outcome in prelingual deafness treatment.

Because of vast variability of cochlear implantation outcomes in prelingual deafness treatment, identification of good and poor performers remains a challenging task. To address this issue, we investigated genetic variants of matrix metalloproteinase 9 (MMP9) and brain derived neurotrophic factor (BDNF) and plasma levels of MMP-9, BDNF, and pro-BDNF that have all been implicated in neuroplasticity after sensory deprivation in the auditory pathway. We recruited a cohort of prelingually deaf children, all implanted before the age of 2, and carried out a prospective observation (N = 61). Next, we analyzed the association between (i) functional MMP9 (rs20445, rs1839242, rs2234681) and BDNF (rs6265) gene variants (and their respective protein levels) and (ii) the child’s auditory development as measured with the LittlEARS Questionnaire (LEAQ) before cochlear implant (CI) activation and at 8 and 18 months post-CI activation. Statistical analyses revealed that the plasma level of MMP-9 measured at implantation in prelingually deaf children was significantly correlated with the LEAQ score 18 months after CI activation. In the subgroup of DFNB1-related deafness (N = 40), rs3918242 of MMP9 was significantly associated with LEAQ score at 18 months after CI activation; also, according to a multiple regression model, the ratio of plasma levels of pro-BDNF/BDNF measured at implantation was a significant predictor of overall LEAQ score at follow-up. In the subgroup with DFNB1-related deafness, who had CI activation after 1 year old (N = 22), a multiple regression model showed that rs3918242 of MMP9 was a significant predictor of overall LEAQ score at follow-up.

Functional Polymorphism of MMP9 and BDNF as Potential Biomarker of Auditory Neuroplasticity in Prelingual Deafness Treatment With Cochlear Implantation—A Retrospective Cohort Analysis

Genetic biomarkers of neuroplasticity in deaf children treated with cochlear implantation (CI) might facilitate their clinical management, especially giving them better chances of developing proficient spoken language. We investigated whether carrying certain variants of the genes encoding matrix metalloproteinase MMP9 and neurotrophin brain-derived neurotrophic factor ( BDNF), involved in synaptic plasticity, can be taken as prognostic markers of how well auditory skills might be acquired. Association analysis of functional MMP9 rs3918242 and BDNF rs6265 variants and the child’s auditory development measured at CI activation and 1, 5, 9, 14, and 24 months post CI activation with LittlEARS Questionnaire (LEAQ) was conducted in a group of 100 children diagnosed with DFNB1-related deafness, unilaterally implanted before the age of 2 years. Statistical analysis in the subgroup implanted after 1 year of life ( n = 53) showed significant association between MMP9 rs3918242 and LEAQ scores at 1 month ( p = .01), at 5 months ( p = .01), at 9 months ( p = .01), and at 24 months ( p = .01) after CI activation. No significant associations in the subgroup implanted before 1 year of life were observed. No significant associations between the BDNF rs6265 and LEAQ score were found. Multiple regression analysis ( R2 = .73) in the subgroup implanted after 1 year of life revealed that MMP9 rs3918242 was a significant predictor of treatment outcome. In conclusion, C/C rs3918242 MMP9 predisposes their deaf carriers to better CI outcomes, especially when implanted after the first birthday, than carriers of C/T rs3918242 MMP9.

Deaf sociocultural identity and experiencing symptoms of depression – a preliminary study of adult CI users with prelingual deafness

Joanna Kobosko, Deaf sociocultural identity and experiencing symptoms of depression – a preliminary study of adult CI users with prelingual deafness. Interdisciplinary Contexts of Special Pedagogy, no. 25, Poznań 2019. Pp. 275-295. Adam MickiewiczUniversity Press. ISSN 2300-391X. DOI: https://doi.org/10.14746/ikps.2019.25.12Deaf sociocultural identity of the deaf is an important issue from the point of view of their psychological and social functioning. The present study was focused on people with prelingual deafness using cochlear implants (CI) demonstrating high skills in oral Polish language. The research question concerned the relation between the aforementioned identity and symptoms of depression, as well as the age, sex and age at cochlear implantation. The study included 28 prelingually deaf CI users aged between 18 and 40 and was conducted using N. Glickman’s DIDS, PHQ-9 and an information questionnaire. Deaf sociocultural identity is similar in terms of proportion of types of identities of the deaf to the results obtained in other studies, i.e. hearing and bicultural identities turned out to be predominant in the study group. The marginal identity only coexists with the presence of depression symptoms.