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For deaf individuals with residual low-frequency acoustic hearing, combined use of a cochlear implant (CI) and hearing aid (HA) typically provides better speech understanding than with either device alone. Because of coarse spectral resolution, CIs do not provide fundamental frequency (F0) information that contributes to understanding of tonal languages such as Mandarin Chinese. The HA can provide good representation of F0 and, depending on the range of aided acoustic hearing, first and second formant (F1 and F2) information. In this study, Mandarin tone, vowel, and consonant recognition in quiet and noise was measured in 12 adult Mandarin-speaking bimodal listeners with the CI-only and with the CI+HA. Tone recognition was significantly better with the CI+HA in noise, but not in quiet. Vowel recognition was significantly better with the CI+HA in quiet, but not in noise. There was no significant difference in consonant recognition between the CI-only and the CI+HA in quiet or in noise. There was a wide range in bimodal benefit, with improvements often greater than 20 percentage points in some tests and conditions. The bimodal benefit was compared to CI subjects’ HA-aided pure-tone average (PTA) thresholds between 250 and 2000 Hz; subjects were divided into two groups: “better” PTA (<50 dB HL) or “poorer” PTA (>50 dB HL). The bimodal benefit differed significantly between groups only for consonant recognition. The bimodal benefit for tone recognition in quiet was significantly correlated with CI experience, suggesting that bimodal CI users learn to better combine low-frequency spectro-temporal information from acoustic hearing with temporal envelope information from electric hearing. Given the small number of subjects in this study (n = 12), further research with Chinese bimodal listeners may provide more information regarding the contribution of acoustic and electric hearing to tonal language perception. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to assess the correlation between residual hearing and audiologic outcomes after cochlear implant (CI) surgery in patients with cochlear nerve deficiency (CND). Methods: This 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. Results: Forty‐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. Conclusion: For 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 Evidence: 4 [ABSTRACT FROM AUTHOR]

Mandarin is a tonal language, and it is important to preserve lexical tone information in synthesized speech. With natural speech, Chinese cochlear implant (CI) users have difficulty perceiving voice pitch cues important for lexical tone perception; it is unclear whether this difficulty persists in Mandarin synthesized speech. In this study, intelligibility of naturally produced and synthesized Mandarin speech was measured in Chinese CI listeners; intelligibility was also measured in a control group of normal-hearing (NH) listeners. Five synthesized voices were selected to represent different talker genders (male, female, child), speaking rates (normal, slow), and speaking styles (emotional, accent). The data showed that while modern Mandarin text-to-speech (TTS) systems can provide perfect speech intelligibility for NH listeners, overall intelligibility was much poorer for CI than for NH listeners. CI performance was significantly poorer with synthesized speech than with natural speech (p < 0.001). CI listeners were highly sensitive to the “extra-atypical” synthesized emotional and accented speech. Performance with each of the synthesized speech types was significantly correlated with performance with natural speech in CI users (p < 0.01 in all cases). While modern TTS systems offer educational and communication benefits to CI users and hearing-impaired individuals, the selection of synthesized voices should be carefully considered in education applications of TTS for hearing-impaired individuals, especially CI children, since poor intelligibility performance may affect language learning. [ABSTRACT FROM AUTHOR]

The aim of this study is to survey and compare the development of auditory skills in young children with Mondini dysplasia and profoundly-deaf young children with radiologically normal inner ears over a period of 3 years after cochlear implantation. A total of 545 young children (age 7 to 36 months) with prelingual, severe to profound hearing loss participated in this study. All children received cochlear implantation. Based on whether or not there was a Mondini dysplasia as diagnosed with CT scanning, the subjects were divided into 2 groups: (A) 514 young children with radiologically normal inner ears and (B) 31 young children with Mondini dysplasia. The Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS) was used to assess the children's auditory skills that include vocalization changes, spontaneous alerting to sounds in everyday living environments, and the ability to derive meaning from sounds. The assessment was performed prior to surgery and at 1, 3, 6, 9, 12, 24, and 36 months after implant device switch-on. The mean scores for overall auditory skills were not significantly different between groups A and B at pre-surgery, 1, 12, 24, and 36 months post-surgery, but were significantly different at 3, 6, and 9 months post-surgery. The mean scores for all auditory skills in children with Mondini dysplasia showed significant improvement over time. The mean scores for the three subcategories of auditory skills in children with Mondini dysplasia also showed significant differences at pre-surgery, 1, 3, 6, and 9 months, however, there were no significant differences at 12, 24, and 36 months. Overall, the auditory skills of young children with Mondini dysplasia developed rapidly after cochlear implantation, in a similar manner to that of young children with radiologically normal inner ears. Cochlear implantation is an effective intervention for young children with Mondini dysplasia. [ABSTRACT FROM AUTHOR]

Incomplete partition type III (IP-III) is a relatively rare inner ear malformation that has been associated with a POU3F4 gene mutation. The IP-III anomaly is mainly characterized by incomplete separation of the modiolus of the cochlea from the internal auditory canal. We describe a 71-year-old woman with profound sensorineural hearing loss diagnosed with an IP-III of the cochlea that underwent cochlear implantation. Via targeted sequencing with a non-syndromic gene panel, we identified a heterozygous c.934G > C p. (Ala31Pro) pathogenic variant in the POU3F4 gene that has not been reported previously. IP-III of the cochlea is challenging for cochlear implant surgery for two main reasons: liquor cerebrospinalis gusher and electrode misplacement. Surgically, it may be better to opt for a shorter array because it is less likely for misplacement with the electrode in a false route. Secondly, the surgeon has to consider the insertion angles of cochlear access very strictly to avoid misplacement along the inner ear canal. Genetic results in well describes genotype-phenotype correlations are a strong clinical tool and as in this case guided surgical planning and robotic execution. [ABSTRACT FROM AUTHOR]