Cochlear Implantation in the Poorer-Hearing Ear Is a Reasonable Choice.

Choosing the optimal side for cochlear implantation (CI) remains a major challenge because of the lack of evidence. We investigated the choice of the surgery side for CI (i.e., the better- or poorer-hearing ear) in patients with asymmetric hearing. Audiological records of 74 adults with a unilateral hearing aid who had undergone surgery at Okayama University Hospital were reviewed. The definition of 'better-hearing ear' was the aided ear, and the unaided ear was considered the poorer-hearing ear. We performed a multiple regression analysis to identify potential predictors of speech recognition performance after unilateral CI in the patients. Fifty-two patients underwent CI in the poorer-hearing ear. The post-Ci bimodal hearing rate was far higher in the poorer-ear group (77.8% vs. 22.2%). A multivariate analysis revealed that prelingual hearing loss and the patient's age at CI significantly affected the speech recognition outcome (beta coefficients: 24.6 and -0.33, 95% confidence intervals [11.75-37.45] and [-0.58 to -0.09], respectively), but the CI surgery side did not (-6.76, [-14.92-1.39]). Unilateral CI in the poorer-hearing ear may therefore be a reasonable choice for adult patients with postlingual severe hearing loss, providing a greater opportunity for postoperative bimodal hearing.

Revision cochlear implant surgery in adults and children is a safe and effective technique: a retrospective single faculty study in Okayama University Hospital, Japan.

BACKGROUND: Cochlear implant (CI) surgery is a safe surgical technique, although some patients require revision CI surgery. AIMS/OBJECTIVES: This study investigated the cause and underlying reason of revision CI surgery as well as hearing outcomes in a single institution. PATIENTS AND METHODS: This retrospective study evaluated patients who underwent CI surgery between April 2006 to March 2022 (n = 351). Sex, aetiology of hearing loss (HL), age and period from initial CI surgery to reimplantation, cause of revision, and related factors were examined. RESULTS: Twelve patients (8 males, 4 females) received CI reimplantation. The revision surgery rate was 2.59% (3.15% children, 1.69% adults); the period from initial surgery to reoperation was 8.60 ± 6.56 years for 9 children with congenital HL and 15.27 ± 5.72 years for 3 adults with progressive HL. Device failure was the most common cause (n = 8), followed by infections (n = 2), advanced facial irritation symptoms (n = 1), and electrode slip-out (n = 1). Mean preoperative and postoperative CI thresholds were 44.0 ± 9.46 dBnHL and 39.19 ± 8.89 dBnHL (p < .068), respectively. CONCLUSION AND SIGNIFICANCE: Caregiver education, surgical technique advances, flap design, and extensive antibiotic use may decrease the revision surgery rate. The lack of post-revision deterioration of the hearing threshold contributed to well-being in patients with CI.

Features predicting treatment failure in pediatric acute otitis media.

OBJECTIVES: To facilitate better antibiotic stewardship, we conducted this clinical trial to identify the prognostic features of treatment failure in pediatric acute otitis media (AOM). STUDY: Design: This is a randomized, parallel-group, open-label, comparative clinical trial. SUBJECTS AND METHODS: Children with AOM and aged between 1 month and 5 years were enrolled. Patients were randomly assigned to receive either amoxicillin alone (70 mg/kg) for five days, or the same with additional clarithromycin (15 mg/kg) for the initial three days. The clinical course of AOM was evaluated based on tympanic membrane scores. Failure of treatment for AOM was confirmed on day 14. Nasal conditions were also assessed by a clinical scoring system for acute rhinosinusitis. RESULTS: Treatment failures occurred in 25 out of 129 (19.4%) children. The ratio of treatment failures by age was significantly higher in children younger than 2 years than in children older than 2 years. The tympanic membrane scores on day 3 (P = 0.0334) and day 5 (P < 0.0001) and acute rhinosinusitis scores on day 5 (P = 0.0004) were higher in failure cases than in cured cases. Multivariate logistic regression analysis indicated significant associations between the treatment failure with tympanic membrane scores and acute rhinosinusitis scores on day 5, and the antimicrobial treatment regimen. CONCLUSIONS: Improvement of acute rhinosinusitis and tympanic membrane scores on day five were important predictive features in failure of treatment for pediatric AOM. These results will be useful when discussing the treatment decisions with the patient's parents.

Prevalence and risk factors for delayed-onset hearing loss in early childhood: A population-based observational study in Okayama Prefecture, Japan.

OBJECTIVES: The aim of this study was to retrospectively document prevalence rates of delayed-onset hearing loss (DOHL) under 7 years old after passing the newborn hearing screening (NHS) program using its database in Okayama Prefecture, as well as records from Okayama Kanariya Gakuen (OKG, Auditory Center for Hearing Impaired Children, Okayama Prefecture, Japan). We explored the percentage of children with DOHL among all children who underwent the NHS and surveyed risk factors abstracted from their clinical records. METHODS: We collected data of 1171 children, who first visited OKG from April 2006 to March 2018. DOHL children were defined as bilaterally hearing-impaired children who were diagnosed under 7 years old after passing the NHS at birth. Based on the medical records, we investigated age at diagnosis, hearing levels, and risk factors. As population-based data of 168,104 children, the percentage of DOHL subjects was retrospectively calculated among the total number of children who underwent the NHS in Okayama Prefecture from April 2005 to March 2017. RESULTS: During the period, we identified 96 children with bilateral DOHL, of which 34 children had failed the NHS unilaterally and 62 had passed the NHS bilaterally. Among all children who underwent the NHS in Okayama Prefecture, the prevalence rate of DOHL in unilaterally referred infants was 5.2%, and 0.037% in bilaterally passed children. The prevalence of bilateral DOHL was 0.057% overall. Unilaterally referred children with DOHL were diagnosed at an average of 13.9 months, while bilaterally passed children with DOHL were diagnosed at an average of 42.3 months. Approximately 59.4% of children with DOHL had risk factors, among which family history of hearing loss was the most frequent. CONCLUSION: We propose the first English report of DOHL prevalence in the prefecture population in Japann, which is among the largest community-based population ever reported. The NHS is not a perfect strategy to detect all early-childhood hearing loss; therefore, careful assessment of hearing throughout childhood is recommended, especially in children with risk factors of hearing loss. Further interventional strategies must be established, such as regular hearing screening in high-risk children and assessments of hearing and speech/language development in public communities and nursery schools.

Impact of reading and writing skills on academic achievement among school-aged hearing-impaired children.

OBJECTIVES: Reading and writing skills are important for hearing-impaired children since these skills help them to develop their language skills, but the prevalence of reading/writing difficulties and its effects on language development aspects among them are unclear. In this study, we identified language development features and demographic factors of Japanese hearing-impaired children diagnosed as having reading/writing difficulties. METHODS: We analyzed data from a total of 546 sever-to-profound pre-school and elementary school hearing-impaired children for this study. Children with reading/writing difficulties (Group A) were defined as children obtaining low scores (-1.5 SD compared to others in the same grade) in the Screening Test of Reading and Writing for Japanese Primary School Children (STRAW), and we compared other language development features (communication ability, vocabulary, syntax and academic achievement) and demographic factors to those of hearing-impaired children with normal reading and writing skills (Group B). We assessed language development domains as outcomes using the Assessment of Language Development for Japanese Children (ALADJIN) package, and analyzed the results stratified by age groups (5-6, 7-8, 9-10, and 11-12 years) using multiple regression analyses. RESULTS: The prevalence of reading/writing difficulties was 20.1% among the participants. Almost all point estimates in each language development domain showed better odds ratios (OR) except Criterion Referenced Test -II (CRT-II) mathematics in 11- to 12-year-olds in fully-adjusted models. Among 9- to 10-year-olds, the ORs (95% confidence interval) for fair academic achievement measured by CRT-II were 2.60 (1.09-6.20) for Japanese and 3.02 (1.29-7.11) for mathematics in Group B, even after adjusting for possible confounding factors. CONCLUSIONS: Reading and writing are important for language development of hearing-impaired children, especially for academic achievement during the middle phase of elementary school. Screening for reading/writing difficulties is important for appropriate intervention and to prevent language and academic delays among hearing-impaired children.

A nationwide multicenter study of the Cochlin tomo-protein detection test: clinical characteristics of perilymphatic fistula cases.

OBJECTIVE: To investigate the positive rate for the Cochlin tomo-protein (CTP: an inner ear-specific protein) detection test among patients with inner ear-related clinical manifestations and evaluate the clinical characteristics of definite perilymphatic fistula (PLF). METHODS: We have performed an ELISA-based CTP detection test using middle ear lavage (MEL) samples from 497 cases of suspected PLF enrolled from 70 clinical centers nationwide between 2014 and 2015. In addition to the CTP-positive rate, audio-vestibular symptoms were compared between CTP-positive and -negative cases. RESULTS: 8-50% of patients in category 1 (trauma, middle and inner ear disease cases), and about 20% of those in categories 2, 3 and 4 (external origin antecedent events, internal origin antecedent events, and without antecedent event, respectively) were positive for CTP. In category 1 cases, the earlier tested samples showed a higher CTP-positive rate, whereas no differences were observed in categories 2, 3 or 4. The characteristic clinical features in the earlier tested cases were nystagmus and fistula sign in CTP test-positive cases in category 1, and streaming water-like tinnitus in those in categories 2, 3 and 4. CONCLUSION: The present study clarified that CTP detection test-positive patients exist at considerable rates among patients with inner ear-related manifestations.

Theory of mind and language development in Japanese children with hearing loss.

OBJECTIVE: This study investigates the development of theory of mind (ToM) in Japanese children with hearing loss (HL) and its relationship with language abilities using the data of a large sample size. METHODS: Participants were 369 children with HL, ranging from 4 to 12 years of age. The mean hearing level of the better ear was 100.7 dB. A "change in location"-type false belief task similar to the "Sally-Anne test" was given to the participants. RESULTS: The pass rates for the false belief task were in the 20% range for 4 to 6-year-olds, 35.6% for 7-year-olds, 47.6% for 8-year-olds, and 63.6% for 9-year-olds. However, no children, even 12-year-olds, achieved a pass rate of 70%. A logistic regression analysis showed that the significant independent predictors of the false belief task performance were vocabulary age and syntactic comprehension level, and chronological age, hearing level, syntactic production level, and nonverbal intelligence were excluded. CONCLUSION: The results demonstrate that there is a delay in the development of ToM in Japanese children with HL. This finding is consistent with findings in English-speaking countries. Additionally, it is suggested that language abilities play an important role in the acquisition of ToM for children with HL.

A nationwide study on enlargement of the vestibular aqueduct in Japan.

OBJECTIVE: To document the clinical features and associated pure-tone audiometry data in patients with enlargement of the vestibular aqueduct (EVA), and to identify risk factors for fluctuating hearing loss (HL) and vertigo/dizziness in EVA patients. METHODS: In this nationwide survey in Japan, a first survey sheet was mailed to 662 board-certified otolaryngology departments to identify the ones treating EVA patients. A second survey sheet, which contained solicited clinical information and the results of the hearing tests, was mailed to all facilities that reported treating EVA cases. We analyzed clinical information, including age at the time of the most recent evaluation, gender, EVA side, age at onset, initial symptoms, precipitating factors, and etiology from survey responses, and assessed 4-frequency (500, 1000, 2000, and 4000Hz) pure-tone average (PTA) from accompanying pure-tone audiometry data. A multivariate logistic regression analysis was utilized to identify the possible risk factors for fluctuating HL and vertigo/dizziness. RESULTS: In total, 513 hospitals (response rate, 77.5%) responded to the first survey, and 113 reported treating patients with EVA. Seventy-nine out of the 113 hospitals (response rate 69.9%) responded to the second survey, and the data of 380 EVA patients were registered and analyzed. Of the 380 patients, 221 (58.2%) were female, suggesting female preponderance. The patient age ranged from 0 to 73 years (mean, 16.7 years; median, 13 years; interquartile range, 6-24 years). EVA was bilateral in 91.1% of the patients (346/380). The most prevalent initial symptom was HL (341/380), followed by vertigo/dizziness/imbalance (34/380). Sudden HL occurred secondary to head trauma in 5.3% of the patients and upper respiratory infection in 5.0%. Pure-tone audiometry showed profound HL (PTA >91dB) in 316 (52.0%) of the 608 ears in the 304 patients tested, and asymmetric HL, defined as >10dB, in 147 (48.4%) of the 304 patients. The mean PTA was 83.7dB (median, 91.3dB; interquartile range, 71.3-103.8dB), and the severity in PTA did not correlate with age. Multivariate logistic regression identified age ≥10 years (compared to age of 0-9 years), bilateral HL (compared to unilateral HL/normal hearing), a history of head trauma, and Pendred syndrome (compared to the other EVA-associated disorders) as significant risk factors for fluctuating HL and/or vertigo/dizziness. CONCLUSION: The present nationwide survey of 380 EVA patients provided a more precise description of the clinical features, including risk factors for fluctuating HL and vertigo/dizziness.

Genetic Counseling of a Hearing-impaired Patient with Multiple Genetic Mutations.

Since April 2012, genetic testing for congenital hearing loss is covered by the public health insurance in Japan. Recent (since August 2015) developments in next-generation sequencing technology have enabled the detection of 154 mutations in 19 genes. Genetic testing provides valuable information on hearing phenotype, prognosis, and prediction of associated symptoms. We report a hearing-impaired patient in whom multiple genetic mutations were detected. This patient carries two missense mutations in GJB2 (p.G45E, p.Y136X), as well as a mitochondrial mutation (7445A>G). Since the number of genes detectable by genetic testing has increased, the diagnosis of hearing loss can be made with greater accuracy. However, it is often difficult to clinically understand and interpret the genotype information, especially when multiple gene variants are detected in one patient or family. Genetic counseling plays an important part in the intervention for or follow-up of such patients. Genotypic and phenotypic information of other family members is necessary, so that both the patient and the family can understand and accept the results of genetic testing.

Pediatric central auditory processing disorder showing elevated threshold on pure tone audiogram.

Central auditory processing disorder (CAPD) is a condition in which dysfunction in the central auditory system causes difficulty in listening to conversations, particularly under noisy conditions, despite normal peripheral auditory function. Central auditory testing is generally performed in patients with normal hearing on the pure tone audiogram (PTA). This report shows that diagnosis of CAPD is possible even in the presence of an elevated threshold on the PTA, provided that the normal function of the peripheral auditory pathway was verified by distortion product otoacoustic emission (DPOAE), auditory brainstem response (ABR), and auditory steady state response (ASSR). Three pediatric cases (9- and 10-year-old girls and an 8-year-old boy) of CAPD with elevated thresholds on PTAs are presented. The chief complaint was difficulty in listening to conversations. PTA showed elevated thresholds, but the responses and thresholds for DPOAE, ABR, and ASSR were normal, showing that peripheral auditory function was normal. Significant findings of central auditory testing such as dichotic speech tests, time compression of speech signals, and binaural interaction tests confirmed the diagnosis of CAPD. These threshold shifts in PTA may provide a new concept of a clinical symptom due to central auditory dysfunction in CAPD.

SOD1 gene polymorphisms in sudden sensorineural hearing loss.

CONCLUSION: The results suggest that SOD1 rs4998557 could be associated with susceptibility to SSNHL in the Japanese population. OBJECTIVES: To assess the gene association with sudden sensorineural hearing loss (SSNHL). METHODS: A two-stage case control study was conducted to explore the relationship of the candidate genes to SSNHL. The 192 gene samples from SSNHL patients registered in the intractable inner ear disease gene bank were enrolled. As the candidate genes, 39 SNPs from 31 genes were selected for the first stage study. The second stage study examined whether the SOD1 gene polymorphisms, defined by significant differences between cases and controls in the first stage study, are associated with SSNHL. RESULTS: Significant differences were observed in four SNPs from three genes, Glutathione-S-transferase pai 1 (GSTP1), proteine kinase C heta (PRKCH), and superoxide dismutase 1 (SOD1), in terms of allele frequency between SSNHL patients and HapMap controls. In the SOD1 gene, a significant difference was observed in the dominant model study of the SNP rs4998557 in the second stage study. Furthermore, as a result of dividing SSNHL patients based on the clinical data, the difference was more apparent in the case of the over 60 dB group and the tinnitus-positive group.

Impact of early intervention on comprehensive language and academic achievement in Japanese hearing-impaired children with cochlear implants.

OBJECTIVES: Early hearing detection and intervention (EHDI) is critical for achievement of age-appropriate speech perception and language development in hearing-impaired children. It has been 15 years since newborn hearing screening (NHS) was introduced in Japan, and its effectiveness for language development in hearing-impaired children has been extensively studied. Moreover, after over 20 years of cochlear implantation in Japan, many of the prelingual cochlear implant (CI) users have reached school age, and the effect of CI on language development have also been assessed. To identify prognostic factors for language development, audiological/language test scores and demographic factors were compared among prelingual severe-to-profound hearing-impaired children with CI divided into subgroups according to age at first hearing aid (HA) use and whether they received NHS. METHODS: Prelingual severe-to-profound deafened children from the Research on Sensory and Communicative Disorders (RSCD) project who met the inclusion criteria were divided into groups according to the age (in months) of HA commencement (before 6 months: group A, after 7 months: group B), and the presence or absence of NHS (groups C and D). Language development and socio-economic data were obtained from audiological/language tests and a questionnaire completed by caregivers, respectively. RESULTS: In total, 210 children from the RSCD project participated in this study. Group A (n=49) showed significantly higher scores on comprehensive vocabulary and academic achievement (p<0.05) than group B (n=161), with no difference in demographics except for significantly older age in group B. No differences in language scores were observed between group C (n=71) and group D (n=129), although participants of group D was significantly older and had used CIs longer (p<0.05). CONCLUSIONS: Early use of HAs until the CI operation may result in better language perception and academic achievement among CI users with prelingual deafness. A long-term follow-up is required to assess the usefulness of NHS for language development.

Outcomes of consonant-vowel monosyllable perception and word recognition after cochlear implantation in elderly Japanese patients.

CONCLUSION: Performance in consonant-vowel (CV) monosyllable speech perception after cochlear implantation (CI) in the elderly (≥ 65 years) is equivalent to that of young adults (18-64 years). Present data in the Japanese language supported the indication for CI in the elderly. Word recognition after CI was significantly lower in the elderly than young adults. OBJECTIVE: This study compared outcomes of monosyllable perception and word recognition after CI between elderly patients and young adults with post-lingual deafness. Age-related differences in CV monosyllable speech perception in Japanese were examined. METHODS: A retrospective chart review of 137 patients with post-lingual deafness who underwent CI at Okayama University Hospital during 1992-2014 [young adults aged 18-64 years (n = 96) and elderly aged ≥ 65 years (n = 41) at implantation] was conducted. CV monosyllable speech perception post-CI was compared among age groups (18-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80-89). CV monosyllable perception and word recognition scores post-CI were compared between the elderly and young adults. RESULTS: There was no significant difference in CV monosyllable speech perception among age groups. CV monosyllable speech perception in the elderly (61.4 ± 25.5%) did not differ from that of young adults (65.9 ± 24.8%). Word recognition scores were significantly lower in the elderly (64.3 ± 28.1%) than young adults (80.4 ± 25.9%) (p < 0.05).

Dexamethasone Regulates Cochlear Expression of Deafness-associated Proteins Myelin Protein Zero and Heat Shock Protein 70, as Revealed by iTRAQ Proteomics.

AIM: Using proteomics, we aimed to identify the proteins differentially regulated by dexamethasone in the mouse cochlea based on mass-spectrometry data. BACKGROUND: Glucocorticoid therapy is widely used for many forms of sensorineural hearing loss; however, the molecular mechanism of its action in the cochlea remains poorly understood. METHODS: Dexamethasone or control saline was intratympanically applied to the cochleae of mice. Twelve hours after application, proteins differentially regulated by dexamethasone in the cochlea were analyzed by isobaric Tag for Relative and Absolute Quantitation (iTRAQ)-mass spectrometry. Next, dexamethasone-dependent regulation of these proteins was verified in the cochleae of mice with noise-induced hearing loss (NIHL) and systemic administration of dexamethasone by western blotting. Immunolocalizations of these proteins were examined in cochleae with NIHL. RESULTS: A total of 247 proteins with a greater than 95% confidence interval of protein identification were found, and 11 differentially expressed proteins by dexamethasone were identified by the iTRAQ-mass spectrometry. One protein, myelin protein zero (Mpz), was upregulated (1.870 ± 0.201-fold change, p < 0.01) at 6 hours post-systemic dexamethasone and noise exposure in a mouse model of NIHL. Heat shock protein 70 (Hsp70) was downregulated (0.511 ± 0.274-fold change, p < 0.05) at 12 hours post-systemic dexamethasone. Immunohistochemistry confirmed Mpz localization to the efferent and afferent processes of the spiral neurons, whereas Hsp70 showed a more ubiquitous expression pattern in the cochlea. CONCLUSION: Both Mpz and Hsp70 have been reported to be closely associated with sensorineural hearing loss in humans. Dexamethasone significantly modulated the expression levels of these proteins in the cochleae of mice.

Novel ABHD12 mutations in PHARC patients: the differential diagnosis of deaf-blindness.

OBJECTIVE: This study examines ABHD12 mutation analysis in 2 PHARC patients, originally thought to be Usher syndrome. METHODS: The ABHD12 gene of 2 patients, who suffered from deaf-blindness and dysfunctional central and peripheral nervous systems, were sequenced. RESULTS: We identified that both cases carried the same novel splice site mutation in the ABHD12 gene. However, 1 had epilepsy and the other had peripheral neuropathy. Based on haplotype analysis, the mutation is likely not a hot spot, but rather could be attributable to a common ancestor. CONCLUSION: This study shows that PHARC has phenotypic variability, even within a family, which is consistent with previous reports. Differential diagnosis of "deaf-blindness" diseases is crucial. Confirming the presence of associated symptoms is necessary for differentiating some deaf-blindness syndromes. In addition, mutation analysis is a useful tool for confirming the diagnosis.

Does the introduction of newborn hearing screening improve vocabulary development in hearing-impaired children? A population-based study in Japan.

OBJECTIVE: Permanent hearing impairment has a life-long impact on children and its early identification is important for language development. A newborn hearing screening (NHS) program has started in Okayama Prefecture, Japan, in 1999 to detect hearing impairment immediately after birth. We aim to examine the effect of this screening program on vocabulary development in pre-school children in a before and after comparative study design. METHODS: A total of 107 5-year-old children who graduated from Okayama Kanariya Gakuen (an auditory center for hearing-impaired children) between 1998 and 2011 were enrolled in this study. The pre-NHS group (n=40) was defined as those who graduated between 1998 and 2003, while the post-NHS group (n=67) was defined as those who graduated between 2004 and 2011. The primary outcome was receptive vocabulary, which was assessed by the Picture Vocabulary Test [score <18 (low) vs. score ≥18 (high)]. The secondary outcome was productive vocabulary, or the number of productive words, which was assessed by an original checklist [<1773 words (low) vs. ≥1773 (high)]. We calculated odds ratios and 95% confidence intervals for vocabulary development and compared both groups. RESULTS: The adjusted Picture Vocabulary Test score and number of productive words were significantly higher (p<0.01) in the post-NHS group than the pre-NHS group. Odds ratios were 2.63 (95% confidence interval: 1.17-5.89) for receptive vocabulary and 4.17 (95% confidence interval: 1.69-10.29) for productive vocabulary. CONCLUSIONS: The introduction of NHS in Okayama Prefecture significantly improved both receptive and productive vocabulary development in hearing-impaired children.

[Assessment of hearing aid outcome using CADL].

The presence of hearing impairment deteriorates patients' quality of life by affecting their daily-life communication. Several self-report assessments are available to evaluate the subjective outcome of hearing aids, however, the procedures to evaluate the impairment of communication induced by hearing impairment has not been well established. A PC-recorded audio file prepared to evaluate the communication ability of hearing aid users, by extracting fifteen spoken language items from the Communication ADL Test: sp-CADL. A before and after study was performed among the hearing aid users who were attending Okayama University Hospital to evaluate the improvement in each of the 15 sp-CADL scores. Twenty-one adults were included in this study whose age ranged from 22 to 83 years old (mean: 56.7 years old). The total and individual scores of the sp-CADL improved significantly after the use of the hearing aids (p < 0.05). The total sp-CADL score of the patients with hearing aids showed a good correlation with the best scores of the speech discrimination test measured before wearing hearing aids.

Massively parallel DNA sequencing facilitates diagnosis of patients with Usher syndrome type 1.

Usher syndrome is an autosomal recessive disorder manifesting hearing loss, retinitis pigmentosa and vestibular dysfunction, and having three clinical subtypes. Usher syndrome type 1 is the most severe subtype due to its profound hearing loss, lack of vestibular responses, and retinitis pigmentosa that appears in prepuberty. Six of the corresponding genes have been identified, making early diagnosis through DNA testing possible, with many immediate and several long-term advantages for patients and their families. However, the conventional genetic techniques, such as direct sequence analysis, are both time-consuming and expensive. Targeted exon sequencing of selected genes using the massively parallel DNA sequencing technology will potentially enable us to systematically tackle previously intractable monogenic disorders and improve molecular diagnosis. Using this technique combined with direct sequence analysis, we screened 17 unrelated Usher syndrome type 1 patients and detected probable pathogenic variants in the 16 of them (94.1%) who carried at least one mutation. Seven patients had the MYO7A mutation (41.2%), which is the most common type in Japanese. Most of the mutations were detected by only the massively parallel DNA sequencing. We report here four patients, who had probable pathogenic mutations in two different Usher syndrome type 1 genes, and one case of MYO7A/PCDH15 digenic inheritance. This is the first report of Usher syndrome mutation analysis using massively parallel DNA sequencing and the frequency of Usher syndrome type 1 genes in Japanese. Mutation screening using this technique has the power to quickly identify mutations of many causative genes while maintaining cost-benefit performance. In addition, the simultaneous mutation analysis of large numbers of genes is useful for detecting mutations in different genes that are possibly disease modifiers or of digenic inheritance.

Effectiveness of domain-based intervention for language development in Japanese hearing-impaired children: a multicenter study.

OBJECTIVE: Decreasing language delay in hearing-impaired children is a key issue in the maintenance of their quality of life. Language training has been presented mainly by experience-based training; effective intervention programs are crucially important for their future. The aim of this study was to confirm the efficacy of 6-month domain-based language training of school-age, severe-to-profound hearing-impaired children. METHODS: We conducted a controlled before-after study involving 728 severe-to-profound prelingual hearing-impaired children, including an intervention group (n = 60), control group (n = 30), and baseline study group (n = 638). Language scores of the participants and questionnaires to the caregivers/therapists were compared before and after the intervention. Average monthly increase in each language score of the control group and baseline study group were compared with those of the intervention group. RESULTS: Language scores and the results of the questionnaire of the intervention group showed a significant improvement (P < .05). The average monthly language growth of the intervention group was twice that of the control group and 3 to 4 times that of the baseline study group (P < .05). The effect size was largest in communication (1.914), followed by syntax (0.931). CONCLUSION: Domain-based language training improved the language development and daily communication of hearing-impaired children without any adverse effects.

[The age at which the grade of Special Child Dependent's Allowance Act can be judged in the case of deaf children].

The spread of neonatal hearing screening has made the identification of hearing loss in early childhood possible, and most of the children with hearing loss are diagnosed and provided with early intervention within several months after their birth. However, they have to wait to receive the Special Child Dependent's Allowance until their hearing levels are evaluated with audiometers. Under the Special Child Dependent's Allowance Act now in force, a delay of several years occurs for those children before they can receive the allowance after diagnosis. We retrospectively reviewed hearing test results of children who had not reacted at 90dBnHL bilaterally in ABR within 12 months after birth, and examined when those results were certain enough to determine their allowance eligibility. We found that the eligibility in children with hearing loss alone could be determined at 1 year of age; as for children who had other disorders, since it was mostly difficult to test them with an audiometer, the diagnosis of hearing loss must always be made carefully but it was also possible to determine the eligibility for the allowance at 1 year of age.