A 3-Year Follow-Up and Radiological Analysis of Cochlear Implantation Patients with Cochlear Nerve Deficiency and Modiolar Deficiency-Type Malformations.

OBJECTIVE: Cochlear nerve deficiency (CND) is often combined with modiolar deficiency-type inner ear malformations, which cause variable cochlear implantation (CI) outcomes. We aimed to assess the postoperative development of auditory and speech perception in CND patients with modiolar deficiency-type malformations after 3 years of follow-up to determine the factors correlated with CI outcomes. METHODS: Sixty-seven CND patients with modiolar deficiency-type malformations who underwent CI surgery were retrospectively reviewed. Modiolar deficiency-type malformations included common cavity (CC), cochlear hypoplasia (CH) (including CH-I and CH-II) and incomplete partition-I (IP-I). Categorical auditory performance (CAP) and the infant-toddler meaningful auditory integration scale (MAIS) were used to assess auditory ability. The speech intelligibility rating (SIR) and meaningful use of speech scale (MUSS) were used to assess the speech intelligibility of these CI patients. The CI outcomes were evaluated at 0, 12, 24 and 36 months after implant activation. RESULTS: All patients demonstrated improvements in auditory ability and speech intelligibility after CI. There were no significant differences in CI outcomes at any time point according to the malformation type. The number of nerve bundles within the internal auditory canal (IAC) showed significant differences at 12, 24 and 36 months after CI ( p < 0.05). Patients with one nerve bundle had relatively poor CI outcomes. CONCLUSIONS: CND patients with modiolar deficiency-type malformations showed continuous improvement in auditory and speech abilities after CI. Compared with malformations, the number of nerve bundles should be given more attention when selecting the side for CI.

Machine Learning-Based Prediction of the Outcomes of Cochlear Implantation in Patients With Cochlear Nerve Deficiency and Normal Cochlea: A 2-Year Follow-Up of 70 Children.

Cochlear nerve deficiency (CND) is often associated with variable outcomes of cochlear implantation (CI). We assessed previous investigations aiming to identify the main factors that determine CI outcomes, which would enable us to develop predictive models. Seventy patients with CND and normal cochlea who underwent CI surgery were retrospectively examined. First, using a data-driven approach, we collected demographic information, radiographic measurements, audiological findings, and audition and speech assessments. Next, CI outcomes were evaluated based on the scores obtained after 2 years of CI from the Categories of Auditory Performance index, Speech Intelligibility Rating, Infant/Toddler Meaningful Auditory Integration Scale or Meaningful Auditory Integration Scale, and Meaningful Use of Speech Scale. Then, we measured and averaged the audiological and radiographic characteristics of the patients to form feature vectors, adopting a multivariate feature selection method, called stability selection, to select the features that were consistent within a certain range of model parameters. Stability selection analysis identified two out of six characteristics, namely the vestibulocochlear nerve (VCN) area and the number of nerve bundles, which played an important role in predicting the hearing and speech rehabilitation results of CND patients. Finally, we used a parameter-optimized support vector machine (SVM) as a classifier to study the postoperative hearing and speech rehabilitation of the patients. For hearing rehabilitation, the accuracy rate was 71% for both the SVM classification and the area under the curve (AUC), whereas for speech rehabilitation, the accuracy rate for SVM classification and AUC was 93% and 94%, respectively. Our results identified that a greater number of nerve bundles and a larger VCN area were associated with better CI outcomes. The number of nerve bundles and VCN area can predict CI outcomes in patients with CND. These findings can help surgeons in selecting the side for CI and provide reasonable expectations for the outcomes of CI surgery.

The Chinese version of the Parents' Evaluation of Aural/Oral Performance of Children (PEACH) rating scale for infants and children with normal hearing.

OBJECTIVE: This study aimed to establish Chinese norms for the Chinese version of the Parent's Evaluation of Aural/Oral of Children (PEACH) rating scale. DESIGN AND STUDY SAMPLE: The PEACH scores were collected from 198 parents whose children have normal hearing. The test-retest reliability of the PEACH scale was evaluated in a subgroup of 34 parents. Another 27 parents also filled out a Putonghua Communicative Development Inventory which was used to explore the relationship between the PEACH ratings and language scores. RESULTS: The normative curve was established using a logit regression function. The total scores increase rapidly with increasing age. A plateau starts from 22 months with the PEACH score reaching 90% and achieves the maximum score of 95% by 47 months of age. The test-retest analyses showed high reliability for all subscales, with all the correlation coefficients values exceeding 0.9 (p < 0.01). The 90% and 95% confidence intervals were provided to facilitate evaluation of differences between scores obtained under different conditions. A significant correlation was found between the PEACH total score and language performance (p < 0.05). CONCLUSIONS: Normative data from the Chinese population was provided to enable performance of an individual child to be related to their normally hearing peers.

A normative study of auditory perception in Mandarin-speaking children with categories of auditory Performance-II.

OBJECTIVE: The aim of this study is to investigate the development of auditory skills in Mandarin-speaking children with normal hearing using CAP-II, and to establish the baseline data for evaluating the auditory performance of children with hearing loss on which designs of appropriate hearing rehabilitation programs can be based. MATERIALS AND METHODS: A total of 223 children participated in this study of which 200 children aged from 1 to 60 months were finally included. Their normal hearing was confirmed by examination of hearing history and high-risk registers for hearing loss, as well as by hearing screening. All children were divided into 10 groups with 20 children in each group based on age. The CAP-II scale was administered to evaluate their development of auditory skills. RESULTS: The categories of auditory performance scores of children with normal hearing improved with their age, the best-fit regression function for prediction of scores from age was Score = 0.94 × ln(age) + 0.08 × (age) + 1.16 and prediction of age from score was Age = 0.65 × (score)2-0.14 × (score)-0.23. The overall CAP-II scale exhibited good reliability and validity. CONCLUSIONS: and Significance: An improvement in auditory skill with age in children with normal hearing was observed. Ceiling performance in auditory skills was found at the age of 51 months for normal children. A conversion table between age and scores obtained from the data of this study can be used as a reference for the assessment of clinical hearing ability in children.

Comparison of primary musicality development between children with cochlear implants and children with normal hearing.

Background: It is beneficial for CI patients listen to music. However it is necessary to take steps to improve the musicality of CI patients.Objectives: The aims of the study were to evaluate the primary musicality of children with cochlear implants versus those with normal hearing.Material and methods: Children participating in this study were divided into two groups: the cochlear implant group (CI group) and the normal hearing group (NH group). The 'Musical Ears Evaluation Form for Professionals' was used to evaluate the subjects' primary musicality.Results: The scores for overall and the three subcategories of primary musicality in children with cochlear implants and in those with normal hearing also improved significantly over time (p < .05). The score for overall primary musicality was not significantly different between CI and NH groups in the same hearing age (p > .05). There were significant differences between the two groups in the same chronological age (p < .05).Conclusions and significance: The primary musicality in children with cochlear implants was not significantly different from normal hearing ones at the same hearing age. The primary musicality in children with cochlear implants was significantly lower than that of children with normal hearing at the same chronological age.

Fabricating Pyramidal Lattice Structures of 304 L Stainless Steel by Wire Arc Additive Manufacturing.

Lattice structures have drawn considerable attention due to their superior mechanical properties. However, the existing fabrication methods for lattice structures require complex procedures, as they have low material utilization and lead to unreliable node connections, which greatly restricts their application. In this work, wire arc additive manufacturing is used to fabricate large-scale lattice structures efficiently, without any air holes between rods and panels. The principle and the process of fabricating the rods were analyzed systematically. The influence of the two most important parameters, including heat input and preset layer height, is disclosed. Through optical microscopy, the microstructure of the fabricated steel rods is found to consist of dendritic austenite and skeletal ferrite. The tensile strength of the rods can reach 603 MPa, and their elongation reaches 77%. These experimental results demonstrated the feasibility of fabricating lattice structures using wire arc additive manufacturing.

The development of auditory performance and speech perception in CI children after long-period follow up.

PURPOSE: The main purpose of the current study was to assess the development of auditory and speech perception and the effects of the age at implantation in CI children after long-period follow up. MATERIALS AND METHODS: Five hundred and forty-four young children participated in this study (339 males and 205 females). The age at implantation ranged from 6 months to 36 months. All subjects were prelingually bilateral profound sensorineural hearing loss. They were divided into 3 groups according to the implant ages: group 1 (age at implantation < 12 months, n = 109); group 2 (12 months < age at implantation < 24 months, n = 284); and group 3 (24 months < age at implantation < 36 months, n = 151). The categorical auditory performance (CAP) was used to assess auditory abilities and the speech intelligibility rating (SIR) was used to assess the speech intelligibility of these CI children. The tests were administered at pre-surgery and 1, 3, 6, 12, 24, 36, 48- and 60-months post-surgery. RESULTS: All the subjects demonstrated improvements of auditory abilities and speech intelligibility after CI surgery. The auditory ability developed quickly in 12 months after implantation. However, the speech intelligibility scores show rapid improvement within 24 months post implantation. Significant difference was found between group 1 and group 3, group 2 and group 3 before 12 months post-implantation for CAP and SIR. The three groups of children showed similar development pattern for their auditory abilities and speech intelligibility. CONCLUSION: The results of this study suggested dramatic and continuous improvement of the auditory and speech abilities post implantation in these CI children. Furthermore, the age at implantation played a considerably smaller role in the improvement of hearing and speech abilities. However, earlier implantation still benefits the language development.

Speech development after cochlear implantation in infants with isolated large vestibular aqueduct syndrome.

Background: Few studies on speech performance of children after cochlear implantation (CI) described isolated large vestibular aqueduct syndrome (LVAS). Objective: To investigate speech developmental trajectories of infants with LVAS after CI, and to compare with those who have structurally normal inner ears. Materials and methods: 1112 infants with congenital severe to profound hearing loss participated in this study. 150 infants in group A were diagnosed with LVAS, 962 infants in group B with structurally normal inner ear. The speech performance was assessed via the Meaningful Use of Speech Scale (MUSS). The evaluations were performed pre-implant, 1, 3, 6, 9, 12, 24, 36, 48 and 60 months after CI. Results: The mean scores of the MUSS improved over a 5-year period after implantation in both groups A and B. The LVAS group presented similar speech developmental trajectory to the non-LVAS group at each assessment interval, except pre-operation. There were significant differences in mean scores between vocalizing behavior and oral communication skills, clarification skills of infants in both two groups. Conclusions and significance: Speech performance of infants with LVAS developed rapidly after CI and was similar to infants with structurally normal inner ear. For infants with isolated LVAS, CI had a significant effect and should be recommended as a therapeutic option.

Long-term follow-up of auditory performance and speech perception and effects of age on cochlear implantation in children with pre-lingual deafness.

BACKGROUND: The development of auditory and speech perception ability of children with hearing loss is affected by many factors after they undergo cochlear implantation (CI). Age at CI (CI age) appears to play an important role among these factors. This study aimed to evaluate the development of auditory and speech perception ability and explore the impact of CI age on children with pre-lingual deafness present before 3 years of age. METHODS: Two hundred and seventy-eight children with pre-lingual deafness (176 boys and 102 girls) were included in this study, and the CI age ranged from 6 to 36 months (mean age, 19 months). Categorical auditory performance (CAP) was assessed to evaluate auditory ability, and the speech intelligibility rating was used to evaluate speech intelligibility. The evaluations were performed before CI and 1, 3, 6, 12, 18, 24, 36, 48, and 60 months after CI. RESULTS: The auditory ability of the pre-lingually hearing-impaired children showed the fastest development within 6 months after CI (k = 0.524, t = 30.992, P < 0.05); then, the progress started to decelerate (k = 0.14, t = 3.704, P < 0.05) and entered a plateau at the 24th month (k = 0.03, t = 1.908, P < 0.05). Speech intelligibility showed the fastest improvement between the 12th and 24th months after CI (k = 0.138, t = 5.365, P < 0.05); then, the progress started to decelerate (k = 0.026, t = 1.465, P < 0.05) and entered a plateau at the 48th month (k = 0.012, t = 1.542, P < 0.05). The CI age had no statistical significant effect on the auditory and speech abilities starting at 2 years after CI (P > 0.05). The optimal cutoff age for CI was 15 months. CONCLUSIONS: Within 5 years after CI, the auditory and speech ability of young hearing-impaired children continuously improved, although speech development lagged behind that of hearing. An earlier CI age is recommended; the optimal cutoff age for CI is at 15 months.

Speech development in young children with Mondini dysplasia who had undergone cochlear implantation.

OBJECTIVE: The purpose of this study was to investigate the development of speech skills in young children with Mondini dysplasia and age-matched deaf children with radiologically normal inner ears over a period of 5 years after cochlear implantation (CI). METHODS: In total, 700 congenitally severely to profoundly deaf children (281 girls and 419 boys) participated in this study. All of the participants had undergone unilateral CI surgery before 36 months of age. The participants were categorized into two groups based on the absence or presence of Mondini dysplasia in the implanted ear, as assessed via high-resolution, thin-slice computerized tomography or magnetic resonance imaging: group A comprised 592 children with radiologically normal inner ears and group B comprised 108 children with Mondini dysplasia. The Meaningful Use of Speech Scale (MUSS) and Speech Intelligibility Rating (SIR) were used to evaluate the speech performance of all young children at various time points: pre-surgery and at 1, 3, 6, 12, 24, 36, 48, and 60 months after switch-on programming. RESULTS: The mean scores of SIR and MUSS in children from both group A and group B showed significant improvements over time. No significant differences were found in the mean scores of SIR between the two groups at any time interval during the 5-year follow-up. The mean score of MUSS was significantly different between group A and group B at 12, 24, and 36 months after implantation, whereas no obvious differences were noted pre-surgery, and at 1, 3, 6, 48, and 60 months post-operation. CONCLUSIONS: Young children with Mondini dysplasia develop their speech skills at a fast rate and achieve similar speech acquisition compared to age-matched children with radiologically normal inner ears 5 years post-operation. Therefore, CI is an effective intervention method for young children with Mondini dysplasia.

The analysis of reliability and validity of the IT-MAIS, MAIS and MUSS.

OBJECTIVE: The aim of this study was to investigate the reliability and validity of the Infant-toddler Meaningful Auditory Integration Scale (IT-MAIS), Meaningful Auditory Integration Scale (MAIS), and Meaningful Use of Speech Scale (MUSS). METHODS: IT-MAIS, MAIS and MUSS were divided into 3 sub dimensions. 300 children with cochlear implants (CI) were included in the investigation. To assess test-retest reliability of these questionnaires, 30 children were selected randomly to be evaluated at a two-week interval indicated that there were no significant changes between test and retest. Furthermore random test analysis by different evaluators was also administered to 30 users. RESULTS: Reliability test: Test-retest reliability of the three scales was proved to be satisfactory. All domains had correlation coefficients that exceeded 0.750(P < 0.01). The Cronbach's α of the three scales and their three domains were greater than 0.700. Reliability between evaluators of the three scales were considered to be satisfactory. All domains had correlation coefficients that exceeded 0.750(P < 0.01). Validity test: The evaluation of content validity by expert review showed the questionnaire had good content validity; The correlation coefficients between the overall scores of the three scales and their three domains were 0.699-0.978(P < 0.01). There were correlations among the three sub-domains but the strength of the correlations was relatively low. There was certain construct validity. CONCLUSIONS: IT-MAIS, MAIS, MUSS scales have good reliability and validity, and can be used to measure the outcome for children with cochlear implants hearing and speech evaluation.

Speech performance in pediatric users of Nurotron ® Venus™ cochlear implants.

OBJECTIVES: The primary purpose of this study was to investigate the longitudinal speech performance over 3 years in pediatric users of the Nurotron(®) cochlear implant system. The secondary purpose was to compare the speech performances of younger and older children with cochlear implants (CIs). METHODS: The Mandarin Early Speech Perception (MESP), Meaningful Use of Speech Scale (MUSS), and Putonghua Chinese Communicative Development Inventory (PCDI) were used to evaluate speech performance of 22 Mandarin-speaking pediatric CI users throughout the first 36 months post-implantation. The subjects were grouped according to the age at implantation, i.e., younger CI group (<3 years) and older CI group (>3 years). RESULTS: All the subjects demonstrated improvement in speech performance throughout the first 3 years of implant use with mean scores reaching the maximum performance at 36 months post-implantation. The median categories of MESP increased from 0.23 pre-implantation to 5.57 three years post-implantation. Likewise, the median percentage of MUSS was 5.57% to 73.75%; the median performance of PCDI was 55 to 400 for PCDI-comprehension and 32 to 384 for PCDI-production at the same interval. At nearly all test intervals, the older group performed better than the younger group except 24 months post-implantation, at which the MUSS score of the younger CI group was higher than that of the older CI group. CONCLUSION: The children with Nurotron(®) Venus™ CI system showed considerable gains in speech and language development including tone performance which improved with hearing age. Earlier implantations haven't presented significantly positive performances until 24 months post-implantation in all the tests.

[The development of musicality in children after cochlear implantation].

OBJECTIVE: The purpose of this study is to analyze the development of musicality in children after cochlear implantation, and provide a clinical database for the evaluation of their musicality. METHOD: Twenty-six children with cochlear implants (CI group) participated in this research. They received cochlear implants at the age of 11 to 68 months with a mean of 35.6 months. Seventy-six infants as a control group aged from 1 to 24 months with a mean of 6.1 months participated in this study, whose hearing were considered normal by passing the case history collection, high-risk registers for hearing loss and hearing screening using DPOAE. The music and young children with CIs: Musicality Rating Scale was used to evaluate their musicality. The evaluation was performed before cochlear implantation and 1, 3, 6, 9, 12, 24 months after cochlear implantation for children with cochlear implants. The evaluation was also performed at 1, 3, 6, 9, 12, 24 months for children with normal hearing. RESULT: The mean scores of musicality showed significant improvements with time of CI use for CI group (P<0.05). The mean scores of musicality also showed significant improvements with time for control group (P<0.05). There were no significant differences in mean scores between CI group and control group at 1, 3, 6, 9, 12 months of hearing age by rank sum test (P>0.05). Significant difference was noted between the two groups at 24 months (P<0.05). CONCLUSION: The musicality of children with cochlear implants improved significantly with time after cochlear implantation. The most rapid growth was found in the first year after cochlear implantation.

Effect of age at cochlear implantation on auditory and speech development of children with auditory neuropathy spectrum disorder.

OBJECTIVE: To evaluate the auditory and speech abilities in children with auditory neuropathy spectrum disorder (ANSD) after cochlear implantation (CI) and determine the role of age at implantation. METHODS: Ten children participated in this retrospective case series study. All children had evidence of ANSD. All subjects had no cochlear nerve deficiency on magnetic resonance imaging and had used the cochlear implants for a period of 12-84 months. We divided our children into two groups: children who underwent implantation before 24 months of age and children who underwent implantation after 24 months of age. Their auditory and speech abilities were evaluated using the following: behavioral audiometry, the Categories of Auditory Performance (CAP), the Meaningful Auditory Integration Scale (MAIS), the Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS), the Standard-Chinese version of the Monosyllabic Lexical Neighborhood Test (LNT), the Multisyllabic Lexical Neighborhood Test (MLNT), the Speech Intelligibility Rating (SIR) and the Meaningful Use of Speech Scale (MUSS). RESULTS: All children showed progress in their auditory and language abilities. The 4-frequency average hearing level (HL) (500Hz, 1000Hz, 2000Hz and 4000Hz) of aided hearing thresholds ranged from 17.5 to 57.5dB HL. All children developed time-related auditory perception and speech skills. Scores of children with ANSD who received cochlear implants before 24 months tended to be better than those of children who received cochlear implants after 24 months. Seven children completed the Mandarin Lexical Neighborhood Test. Approximately half of the children showed improved open-set speech recognition. CONCLUSION: Cochlear implantation is helpful for children with ANSD and may be a good optional treatment for many ANSD children. In addition, children with ANSD fitted with cochlear implants before 24 months tended to acquire auditory and speech skills better than children fitted with cochlear implants after 24 months.

[A normative study of auditory development in Mandarin-speaking infants].

OBJECTIVE: The aim of this study is to investigate the development of auditory skills in Mandarin-speaking infants with normal hearing using IT-MAIS, set up normal comparison data for evaluating the auditory performance of children with hearing loss and provide a basis for establishing an appropriate hearing and speech rehabilitation program for them. METHODS: A total of 183 infants with Mandarin-speaking patents participated in this investigation which was conducted in Beijing, China. 160 infants aged from 1 to 36 months were finally included, whose hearing were considered normal according to the history collection, high-risk registers for hearing loss and hearing screening using DPOAE. All infants were divided into 8 groups with 20 infants in each group by their ages. They were 1 month, 2-3 months, 4-6 months, 7-9 months, 10-12 months, 13-18 months, 19-24 months and 25-36 months group. The IT-MAIS/MAIS were administered to evaluate their development of auditory skills. All statistical analyses were executed using the MATLAB R2010a. RESULTS: The detection scores improved with age and reached ceiling at 19 months in infants with normal hearing, the regression function for prediction of scores from age was score = 0.26×ln(age) + 0.23 and prediction of age from score was age = e([score-0.23])/0.26, r(2) = 0.93. The recognition scores also increased with age and reached ceiling at 24 months in infants with normal hearing, the regression function for prediction of scores from age was score = 0.26×ln(age)-0.07 and prediction of age from score was age = e([score+0.07])/0.34, r(2) = 0.93. The overall scores which combine the above two aspects augmented with age and reached ceiling at 22 months. The regression function for prediction of scores from age was score = 0.3×ln(age)+0.09 and prediction of age from score was age = e([score-0.09])/0.3, r(2) = 0.95. CONCLUSIONS: Auditory skills showed a growth trend with age in infants with normal hearing. Scores of different auditory skills can be predicted according to their age. Age can also be predicted according to their scores of different auditory skills.