Trends in research on cochlear implantation with inner ear malformation: a bibliometric and visualization analysis from 1986 to 2024.

OBJECTIVE: The aim of this study was to conduct a bibliometric and visualization analysis of research on cochlear implantation (CI) for inner ear malformations (IEMs) from 1986 to 2024. METHODS: A comprehensive literature search was performed using the Web of Science Core Collection Database, resulting in the identification of 431 relevant publications. Various data analysis and visualization tools, including VOSviewer, CiteSpace, and Bibliometrix, were utilized to analyze annual publication outputs, countries/regions and institutions, authors, journals and studies, keywords, and theme evolution. RESULTS: The study revealed an overall increasing trend in research output on CI for IEMs, with significant contributions from countries such as the United States, China, Turkey, Germany, and Italy. The analysis also identified key authors, research teams, journals, and studies that have made substantial contributions to the field. Furthermore, the study highlighted important research hotspots and trends, such as the classification of IEMs, outcomes of CI for IEMs, and the management of pediatric patients with IEMs. CONCLUSION: The findings of this study provide a comprehensive overview of the research landscape surrounding CI for IEMs. The results serve as a basis for future research topic selection and emphasize the need for enhanced international collaboration and the publication of high-impact research to further advance this field.

Research progress on incomplete partition type 3 inner ear malformation.

PURPOSE: This review aims to provides a comprehensive overview of the latest research progress on IP-III inner ear malformation, focusing on its geneticbasis, imaging features, cochlear implantation, and outcome. METHODS: Review the literature on clinical and genetic mechanisms associated with IP-III. RESULTS: Mutations in the POU3F4 gene emerge as the principal pathogenic contributors to IP-III anomalies, primarily manifesting through inner ear potential irregularities leading to deafness. While cochlear implantation stands as the primary intervention for restoring hearing, the unique nature of the inner ear anomaly escalates the complexity of surgical procedures and postoperative results. Hence, meticulous preoperative assessment to ascertain surgical feasibility and postoperative verification of electrode placement are imperative. Additionally, gene therapy holds promise as a prospective treatment modality. CONCLUSIONS: IP-III denotes X-linked recessive hereditary deafness, with cochlear implantation currently serving as the predominant therapeutic approach. Clinicians are tasked with preoperative assement and individualized postoperative rehabilitation.

Machine learning-based prediction of the outcomes of cochlear implantation in patients with inner ear malformation.

OBJECTIVE: The objectives of this study are twofold: first, to visualize the structure of malformed cochleae through image reconstruction; and second, to develop a predictive model for postoperative outcomes of cochlear implantation (CI) in patients diagnosed with cochlear hypoplasia (CH) and incomplete partition (IP) malformation. METHODS: The clinical data from patients diagnosed with cochlear hypoplasia (CH) and incomplete partition (IP) malformation who underwent cochlear implantation (CI) at Beijing Tongren Hospital between January 2016 and August 2020 were collected. Radiological features were analyzed through 3D segmentation of the cochlea. Postoperative auditory speech rehabilitation outcomes were evaluated using the Categories of Auditory Performance (CAP) and the Speech Intelligibility Rating (SIR). This study aimed to investigate the relationship between cochlear parameters and postoperative outcomes. Additionally, a predictive model for postoperative outcomes was developed using the K-nearest neighbors (KNN) algorithm. RESULTS: In our study, we conducted feature selection by using patients' imaging and audiological attributes. This process involved methods such as the removal of missing values, correlation analysis, and chi-square tests. The findings indicated that two specific features, cochlear volume (V) and cochlear canal length (CDL), significantly contributed to predicting the outcomes of hearing and speech rehabilitation for patients with inner ear malformations. In terms of hearing rehabilitation, the KNN classification achieved an accuracy of 93.3%. Likewise, for speech rehabilitation, the KNN classification demonstrated an accuracy of 86.7%. CONCLUSION: The measurements obtained from the 3D reconstruction model hold significant clinical relevance. Despite the considerable variability in cochlear morphology across individuals, radiological features remain effective in predicting cochlear implantation (CI) prognosis for patients with inner ear malformations. The utilization of 3D segmentation techniques and the developed predictive model can assist surgeons in conducting preoperative cochlear structural measurements for patients with inner ear malformations. This, in turn, can offer a more informed perspective on the anticipated outcomes of cochlear implantation.

Dysregulation of Grainyhead-like 3 expression causes widespread developmental defects.

BACKGROUND: The gene encoding the transcription factor, Grainyhead-like 3 (Grhl3), plays critical roles in mammalian development and homeostasis. Grhl3-null embryos exhibit thoraco-lumbo-sacral spina bifida and soft-tissue syndactyly. Additional studies reveal that these embryos also exhibit an epidermal proliferation/differentiation imbalance. This manifests as skin barrier defects resulting in peri-natal lethality and defective wound repair. Despite these extensive analyses of Grhl3 loss-of-function models, the consequences of gain-of-function of this gene have been difficult to achieve. RESULTS: In this study, we generated a novel mouse model that expresses Grhl3 from a transgene integrated in the Rosa26 locus on an endogenous Grhl3-null background. Expression of the transgene rescues both the neurulation and skin barrier defects of the knockout mice, allowing survival into adulthood. Despite this, the mice are not normal, exhibiting a range of phenotypes attributable to dysregulated Grhl3 expression. In mice homozygous for the transgene, we observe a severe Shaker-Waltzer phenotype associated with hearing impairment. Micro-CT scanning of the inner ear revealed profound structural alterations underlying these phenotypes. In addition, these mice exhibit other developmental anomalies including hair loss, digit defects, and epidermal dysmorphogenesis. CONCLUSION: Taken together, these findings indicate that diverse developmental processes display low tolerance to dysregulation of Grhl3.

Changes of Otolith and Balance Function Related to Cochlear Implant in Hearing Loss With Inner Ear Malformations Children.

OBJECTIVES: The increase of bilateral cochlear implantation (CI) in recent years has made it essential to comprehend the effects of CI on otolith function. This study aimed to investigate the development of gross motor and otolith function in patients with inner ear malformations (IEMs) using vestibular-evoked myogenic potentials (VEMPs). MATERIALS AND METHODS: Overall, 78 patients with sensorineural hearing loss (SNHL) (age 5.7 ± 4.1 years) were divided into two groups based on the presence (IEM group, n = 39) or absence (control group, n = 39) of IEMs. VEMP testing was performed both before and 1-3 months after CI, and the evaluation of gross motor development was carried out. RESULTS: The mean ages for achieving head control and independent walking were delayed in the IEM group compared with the control group (p = 0.02). The preoperative cervical VEMP (cVEMP) and ocular VEMP (oVEMP) response rates were higher in the control group (60% and 86.95%) than in the IEM group (57.69% and 74.35%) (p < 0.05). Additionally, abnormal cVEMP was associated with delayed acquisition of independent walking (p = 0.017). Saccular and utricular functions after CI were lost by 40% and 31.75%, respectively, in patients who elicited preoperative VEMPs waveform (n = 25). CONCLUSIONS: Among SNHL patients, balance development is more delayed in patients of IEMs than in patients without IEMs. The cVEMP and oVEMP waveforms differed greatly between the two groups. The otolith-vestibular nerve conduction pathway can be affected by CI, potentially leading to otolith function impairment. Therefore, it is essential to assess otolith and balance functions before CI, and this evaluation should be considered an integral part of clinical practice.

Two SOX11 variants cause Coffin-Siris syndrome with a new feature of sensorineural hearing loss.

Coffin-Siris syndrome (CSS, OMIM#135900) is a rare congenital disorder associated with neurodevelopmental and dysmorphic features. The primary cause of CSS is pathogenic variants in any of 9 BAF chromatin-remodeling complex encoding genes or the genes SOX11 and PHF6. Herein, we performed whole-exome sequencing (WES) and a series of analyses of growth-related, auditory, and radiological findings in two probands with syndromic sensorineural hearing loss and inner ear malformations who exhibited distinctive facial features, intellectual disability, growth retardation, and fifth finger malformation. Two de novo variants in the SOX11 gene (c.148A>C:p.Lys50Asn; c.811_814del:p.Asn271Serfs*10) were detected in these probands and were identified as pathogenic variants as per ACMG guidelines. These probands were diagnosed as having CSS based upon clinical and genetic findings. This is the first report of CSS caused by variants in SOX11 gene in Chinese individuals. Deleterious SOX11 variants can result in sensorineural hearing loss with inner ear malformation, potentially extending the array of phenotypes associated with these pathogenic variants. We suggest that both genetic and clinical findings be considered when diagnosing syndromic hearing loss.

Internal auditory canal volume in normal and malformed inner ears.

PURPOSE: A narrow bony internal auditory canal (IAC) may be associated with a hypoplastic cochlear nerve and poorer hearing performances after cochlear implantation. However, definitions for a narrow IAC vary widely and commonly, qualitative grading or two-dimensional measures are used to characterize a narrow IAC. We aimed to refine the definition of a narrow IAC by determining IAC volume in both control patients and patients with inner ear malformations (IEMs). METHODS: In this multicentric study, we included high-resolution CT (HRCT) scans of 128 temporal bones (85 with IEMs: cochlear aplasia, n = 11; common cavity, n = 2; cochlear hypoplasia type, n = 19; incomplete partition type I/III, n = 8/8; Mondini malformation, n = 16; enlarged vestibular aqueduct syndrome, n = 19; 45 controls). The IAC diameter was measured in the axial plane and the IAC volume was measured by semi-automatic segmentation and three-dimensional reconstruction. RESULTS: In controls, the mean IAC diameter was 5.5 mm (SD 1.1 mm) and the mean IAC volume was 175.3 mm3 (SD 52.6 mm3). Statistically significant differences in IAC volumes were found in cochlear aplasia (68.3 mm3, p < 0.0001), IPI (107.4 mm3, p = 0.04), and IPIII (277.5 mm3, p = 0.0004 mm3). Inter-rater reliability was higher in IAC volume than in IAC diameter (intraclass correlation coefficient 0.92 vs. 0.77). CONCLUSIONS: Volumetric measurement of IAC in cases of IEMs reduces measurement variability and may add to classifying IEMs. Since a hypoplastic IAC can be associated with a hypoplastic cochlear nerve and sensorineural hearing loss, radiologic assessment of the IAC is crucial in patients with severe sensorineural hearing loss undergoing cochlear implantation.

Volumetry improves the assessment of the vestibular aqueduct size in inner ear malformation.

OBJECTIVES: Enlarged vestibular aqueduct (EVA) is a common finding associated with inner ear malformations (IEM). However, uniform radiologic definitions for EVA are missing and various 2D-measurement methods to define EVA have been reported. This study evaluates VA volume in different types of IEM and compares 3D-reconstructed VA volume to 2D-measurements. METHODS: A total of 98 high-resolution CT (HRCT) data sets from temporal bones were analyzed (56 with IEM; [cochlear hypoplasia (CH; n = 18), incomplete partition type I (IPI; n = 12) and type II (IPII; n = 11) and EVA (n = 15)]; 42 controls). VA diameter was measured in axial images. VA volume was analyzed by software-based, semi-automatic segmentation and 3D-reconstruction. Differences in VA volume between the groups and associations between VA volume and VA diameter were assessed. Inter-rater-reliability (IRR) was assessed using the intra-class-correlation-coefficient (ICC). RESULTS: Larger VA volumes were found in IEM compared to controls. Significant differences in VA volume between patients with EVA and controls (p < 0.001) as well as between IPII and controls (p < 0.001) were found. VA diameter at the midpoint (VA midpoint) and at the operculum (VA operculum) correlated to VA volume in IPI (VA midpoint: r = 0.78, VA operculum: r = 0.91), in CH (VA midpoint: r = 0.59, VA operculum: r = 0.61), in EVA (VA midpoint: r = 0.55, VA operculum: r = 0.66) and in controls (VA midpoint: r = 0.36, VA operculum: r = 0.42). The highest IRR was found for VA volume (ICC = 0.90). CONCLUSIONS: The VA diameter may be an insufficient estimate of VA volume, since (1) measurement of VA diameter does not reliably correlate with VA volume and (2) VA diameter shows a lower IRR than VA volume. 3D-reconstruction and VA volumetry may add information in diagnosing EVA in cases with or without additional IEM.

[Surgical tactic of cochlear implantation in patients with intraoperative CSF leakage]. / Khirurgicheskaya taktika pri kokhlearnoi implantatsii u patsientov s intraoperatsionnoi likvoreei.

Cochlear implantation (CI) is currently the recognized and most promising method of rehabilitation of patients suffering from profound hearing loss and deafness. During the surgical stage of CI, one of the most unpleasant intraoperative features is CSF leakage from the cochlea opening. Most often it occurs in patients with malformations of the inner ear, with temporal bone fractures and with cochlear otosclerosis. The difficulty of choosing the tactics of surgical intervention in these patients is caused by the large variability of the anatomical structures of the inner ear. In the period from 2017 to 2021, 1954 patients underwent CI, of which 83 were patients with cochlea malformations (65 intraoperative CSF leakages), 14 with the temporal bones fractures (2 intraoperative CSF leakage), 12 with cochlear otosclerosis (1 CSF leakage), while 3 spontaneous intraoperative CSF leakages were noted in patients with normal cochlea anatomy and hyperpnumotized temporal bone pyramid and enlarged vestibular aqueduct. The highest risk of intraoperative CSF leakage was observed in patients with inner ear malformations (common cavity - 10, incomplete partition type III - 15) and anomalies of the internal auditory canal - 5 (dilated IAC - more than 8.5 mm in diameter). Moderate risk of intraoperative CSF leakage was typical for patients with incomplete partition type I (15 patients) and type II (25 patients).

Cochlear Implantation in Inner Ear Malformations: Considerations Related to Surgical Complications and Communication Skills.

INTRODUCTION: There are particular challenges in the implantation of malformed cochleae, such as in cases of facial nerve anomalies, cerebrospinal fluid (CSF) leaks, erroneous electrode insertion, or facial stimulation, and the outcomes may differ depending on the severity of the malformation. The aim of this study was to assess the impact of inner ear malformations (IEMs) on surgical complications and outcomes of cochlear implantation. METHODS: In order to assess the impact of IEMs on cochlear implant (CI) outcomes, 2 groups of patients with similar epidemiological parameters were selected from among 863 patients. Both the study group (patients with an IEM) and control group (patients with a normal inner ear) included 25 patients who received a CI and completed at least 1 year of follow-up. Auditory performance, receptive and expressive language skills, and production and use of speech were evaluated preoperatively and at least 1 year after implantation. Types of surgical complications and rates of revision surgeries were determined in each group. RESULTS: In the study group, the most common malformation was an isolated enlarged vestibular aqueduct (EVA) (44.8%). Overall, the patients with IEMs showed significant improvement in auditory-verbal skills. In general, the patients who had normal cochleae scored significantly better compared to patients with IEMs (p < 0.05). The complication rate was significantly lower in the control group compared to the study group (p = 0.001), but the rate of revision surgeries did not differ significantly (p = 0.637). CONCLUSION: It is possible to improve communication skills with CIs in patients with IEMs despite the variations in postoperative performances. Patients with EVA, incomplete partition type 2, and cochlear hypoplasia type 2 were the best performers in terms of auditory-verbal skills. Patients with IEMs scored poorly compared to patients with normal cochleae. CSF leak (gusher or oozing) was the most common complication during surgery, which is highly likely in cases of incomplete partition type 3.

Postural Control in Subjects with Incomplete Partition Inner Ear Malformations: A Comparison of Incomplete Partition Types.

INTRODUCTION: Children with inner ear malformation (IEM) are at risk of vestibular loss as well as hearing loss. Incomplete partition (IP) anomalies constitute about 41% of all IEMs. This study aimed to investigate the postural control in subjects with the same type of IP on both sides and to compare their results with cochlear implant (CI) users without IEM and healthy peers. METHODS: The study group consists of 17 subjects with the same IP types on both sides and using auditory implants on at least one side, with the following 3 groups: 6 IP-I subjects (mean age 12.28 ± 6.25), 6 IP-II subjects (mean age 12.90 ± 3.23), and 5 IP-III subjects (mean age 6.98 ± 3.10). Six unilateral CI users (mean age 11.38 ± 3.57) with normal inner ear structures were included in the CI control group, and 6 healthy peers (10.20 ± 4.79) were included in the healthy control group. The postural control was measured using the Bruininks-Oseretsky Test of Motor Proficiency Second Edition (BOT-2) balance subtest. All devices were turned off during the balance test. RESULTS: The BOT-2 balance scale scores were observed to be significantly different between the IP-I and healthy control group (medians of balance scores being 3.00 and 16.00, respectively, p < 0.001) and the IP-III and healthy control group (medians of balance scores being 6.60 and 16.00, respectively, p = 0.04). The IP-II group had better balance scores (median = 8.00) than those of the other IP groups, although there were no significant differences between the IP-II and other groups (p > 0.05). CONCLUSION: This study demonstrated that subjects with the same IP type on both sides and with early implantation may differ in terms of their postural control abilities depending on their IP type. Subjects with IP should be regularly followed up by the vestibular assessment and supported by their postural control ability by vestibular rehabilitation.

Children with Auditory Brainstem Implant: How Do They Perform in Motor and Language Skills?

BACKGROUND: Young children are able to explore new objects and practice language through the acquisition of motor skills that lead to their overall development. Congenital hearing loss and total vestibular loss may contribute to the delay in speech and motor skill development. OBJECTIVES: To investigate the relationship between motor development performance, speech perception, and language performance in children with auditory brainstem implant (ABI). METHOD: Ten children, aged 4-17 years (mean age 9.76 ± 4.03), fitted with unilateral ABI for at least 2 years due to the presence of labyrinthine aplasia and rudimentary otocyst at least 1 side were included in the study. Several standardized tests, such as Bruininks-Oseretsky Motor Proficiency Test-2 (BOT-2), Children's Auditory Perception Test Battery, Meaningful Auditory Integration Scale (MAIS), and Test of Early Language Development-3, were performed to evaluate their skills of fine motor control, balance, manual dexterity, language, and auditory perception. RESULTS: A significant correlation was established between the BOT-2 manual dexterity and MAIS scores (r = 0.827, p < 0.05) and between the manual dexterity and language skills (for expressive language, r = 0.762, p < 0.05; for receptive language, r = 0.650, p < 0.05). Some of the BOT-2 balance tasks, such as standing on 1 leg on a line with eyes closed, standing on 1 leg on a balance beam with eyes open, standing heel-to-toe on a balance beam, and walking forward heel-to-toe on a line, showed a strong correlation with their receptive and expressive language performance (p < 0.05). CONCLUSION: The current study has indicated that significantly poor manual and balance performances are associated with poor speech perception and language skills in children with ABI. The authors recommend performing a vestibular assessment before and after ABI surgery and the use of a holistic rehabilitation approach, including auditory and vestibular rehabilitation, to support development of the children with ABI.

Enlarged vestibular aqueduct and Mondini Malformation: audiological, clinical, radiologic and genetic features.

PURPOSE: When referring to enlarged vestibular aqueduct (EVA) we should differentiate between nonsyndromic enlarged vestibular aqueduct (NSEVA) and Pendred Syndrome (PDS), a disease continuum associated with pathogenic sequence variants of Pendrin's Gene (SLC26A4) in about half of the cases. The study was aimed to analyse the clinical and audiological features of a monocentric cohort of Caucasian patients with NSEVA/PDS, their genetic assessment and morphological inner ear features. METHODS: We retrospectively reviewed the audiologic, genetic and anamnestic data of 66 patients with NSEVA/PDS followed by our audiology service. RESULTS: SLC26A4 mutations was significantly correlated with the presence of PDS rather than NSEVA (p < 0.019), with the expression of inner ear malformations (p < 0.001) and with different severity of hearing loss (p = 0.001). Furthermore, patients with PDS showed significantly worse pure tone audiometry (PTA) than patients with NSEVA (p = 0.001). Anatomically normal ears presented significantly better PTA than ears associated with Mondini Malformation or isolated EVA (p < 0.001), but no statistically significative differences have been observed in PTA between patients with Mondini Malformation and isolated EVA. CONCLUSION: NSEVA/PDS must be investigated in all the congenital hearing loss, but also in progressive, late onset, stepwise forms. Even mixed or fluctuating hearing loss may constitute a sign of a NSEVA/PDS pathology. Our findings can confirm the important role of SLC26A4 mutations in determining the phenotype of isolated EVA/PDS, both for the type/degree of the malformation, the hearing impairment and the association with thyroid dysfunction.

Postural instability in children with severe inner ear malformations: Characteristics of vestibular and balance function.

OBJECTIVE: To investigate the postural instability and vestibular functions in children with severe inner ear malformations (IEMs). DESIGN: A prospective case-control study. STUDY SAMPLE: The study group consisted of 10 children using unilateral auditory brainstem implant (ABI) with labyrinthine aplasia or rudimentary otocyst. The age-matched control groups consisted of 10 unilateral cochlear implant (CI) users with normal inner ear structures and 10 healthy peers. All tests were performed to implant users when the implants were off. RESULTS: All median VOR gains in the ABI group (median anterior, lateral, and posterior canal 0.15, 0.05, and 0.05, respectively, for the non-implanted sides) were significantly lower than those of the control groups (median VOR gains ≥ 0.90 in both control groups). There were no oVEMP and cVEMP responses in the study group. The mean BOT-2 balance scores of the ABI (3.70 ± 1.34) group was dramatically lower than those of the CI (9.40 ± 2.88) and healthy control (16.20 ± 4.16, p < 0.001). CONCLUSIONS: The postural instability in children with severe IEMs was higher than those in CI users with normal inner ear structures and healthy peers. The level of deficiency in the labyrinthine was more important for postural stability in children.

Sequential Bilateral Cochlear Implantation in a Child with Severe External, Middle, and Inner Ear Malformations: Surgical Considerations and Practical Aspects.

Cochlear implantation (CI) is a safe and beneficial surgery for children with congenital inner ear malformations, with the exception of cochlear nerve aplasia. The combination of microtia with middle and inner ear abnormalities is extremely uncommon and sufficiently severe to make a surgical approach to the cochlea difficult. We report herein the case of a 2-year-old girl who presented with profound bilateral sensorineural hearing loss, congenital aural atresia, microtia, and inner ear malformations. High-resolution computed tomography revealed poor development of the bilateral middle ear spaces, absence of the incus and stapes, aberrant courses of facial nerves, aplastic lateral semicircular canals, and covered round windows. With intraoperative imaging assistance, sequential bilateral CI was performed using a transmastoid approach with no complication. We propose that CI is feasible in patients with severe external and middle ear malformations. However, major malformations increase the risk of complications. As the facial nerve and cochlea are difficult to locate due to the lack of important anatomical landmarks, detailed planning and adequate preparation, including review of the preoperative imaging data, and the use of facial nerve monitoring and intraoperative imaging are very important. In addition, experienced surgeons should perform CI to ensure the success of the operation.

Inner Ear Malformations in Congenital Deafness Are Not Associated with Increased Risk of Breech Presentation.

BackgroundThere is speculation that an immature vestibular system may be associated with breech presentation at delivery. Our aim was to determine whether syndromes with congenital inner ear malformations were accompanied by a higher frequency of breech presentation/malpresentations than in the general population (2%-3%). Methods: A review was conducted for published literature using PubMed/MEDLINE (1936-2016), to determine frequency of breech presentation and transverse lie in cases with congenital deafness (Michel aplasia, Wildervanck syndrome, Mondini-Alexander dysplasia, Waardenburg syndrome, CHARGE syndrome, Large vestibular aqueductal syndrome, Pendred syndrome, Oculo-aurico-vertebral spectrum, Jervel and Lange-Nielsen syndrome, Usher syndrome, and Scheibe dysplasia) and vestibular nerve aplasia. Results: Identified were total of 122 cases. The frequency of breech presentation was 1.64%, and of transverse lie 1.64%, giving a total of 3.28% malpresentations. Conclusion: The results of the study suggest that congenital malformations of the vestibular apparatus are not associated with the increased risk of breech presentation at delivery.

Bimodal stimulation in children with inner ear malformation: One side cochlear implant and contralateral auditory brainstem implant.

OBJECTIVE: To determine audiological outcomes of children who use a cochlear implant (CI) in one ear and an auditory brainstem implant (ABI) in the contralateral ear. DESIGN: Retrospective case review. SETTING: Tertiary referral hospital. PARTICIPANTS: Twelve children followed with CI and contralateral auditory brainstem implant (ABI) by Hacettepe University Department of Otorhinolaryngology and Audiology in Turkey. All children were diagnosed with different inner ear malformations with cochlear nerve aplasia/hypoplasia. CI was planned in the ear with better sound detection during behavioural testing with inserted ear phones and with better CN as seen on MRI. Due to the limited auditory and speech progress with the cochlear implant, ABI was performed on the contralateral ear in all subjects. MAIN OUTCOME MEASURES: Audiological performance and auditory perception skills of children with cochlear nerve deficiency (CND) who use bimodal electrical stimulation with CI and contralateral ABI. RESULTS: Mean age of the subjects was 84.00 ± 33.94 months. Age at CI surgery and ABI surgery was 25.00 ± 10.98 months and 41.50 ± 16.14 months, respectively. However, hearing thresholds only with CI and only with ABI did not reveal significant difference, and auditory perception scores improved with bimodal stimulation. The MAIS scores were significantly improved from unilateral CI to bimodal stimulation (P = .002). Pattern perception and word recognition scores were significantly higher with the bimodal condition when compared to CI only and ABI only conditions. CONCLUSION: Children with CND showed better performance with CI and contralateral ABI combined. Depending on the audiological and radiological results, bimodal stimulation should be advised for children with CND.

Cochlear Nerve Hypoplasia: Audiological Characteristics in Children and Adults.

BACKGROUND: Cochlear nerve deficiency is a general term used to describe both cochlear nerve hypoplasia (CNH) and cochlear nerve aplasia. Although these two conditions can have similar results on audiological evaluation, CNH yields more variation in audiological tests. OBJECTIVES: To describe the audiological characteristics of the CNH cases in our series in relation to radiological findings. METHODS: We reviewed the medical charts, audiological findings, and radiological findings on cases with CNH. We included cases with CNH in one ear or both ears. Out of 90 subjects with CNH, we included a total of 40 individuals (21 women and 19 men; 49 ears) in the current study. We reviewed and analyzed the participants' audiological test results according to the radiological findings. RESULTS: Cases with CNH showed variations according to the cochlear structure. There were 13 normal cochleae, 4 with incomplete partition type I, and 32 with cochlear hypoplasia. The accompanying cochlear apertures also showed variation: 17 were normal, 28 stenotic, and 4 aplastic cochlear apertures. The subjects displayed hearing loss ranging from moderate to profound; furthermore, 4 subjects had no response to sound whatsoever. The degree of hearing loss was not statistically significantly different with regard to the presence or absence of cochlear malformation with CNH (p > 0.005). We observed both sensorineural hearing loss and mixed-type hearing loss among the CNH cases. CONCLUSIONS: CNH is the presence of a cochlear nerve that is smaller in diameter than the facial nerve. It can be accompanied with other associated inner ear malformations of different degrees of severity. We observed degrees of hearing loss ranging from moderate to profound.

Cochlear implants for patients with inner ear malformation: Experience in a cohort of 877 surgeries.

OBJECTIVE: To analyse clinical information from a cohort of 877 cochlear implant (CI) surgeries performed in patients with inner ear malformations and report our experience with this procedure. METHODS: Clinical information on patients with inner ear malformation who underwent CI surgery in our department from January 2010 to April 2017 was analysed. RESULTS: Seven hundred and fifty-four CI surgeries (86.0%) were uneventful but cerebrospinal fluid gusher occurred during surgery in 118 cases (13.5%). Not including the patients lost to follow-up, postoperative Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) scores were collected from 13 patients with common cavity deformity, 38 with IP-I, 11 with hypoplasia, 13 with IP-III, 285 with IP-II and 43 with cochlear nerve deficiency. The mean CAP scores were 2.55, 3.39, 3.45, 3.77, 3.98, 2.95 and 2.90, and the mean SIR scores were 1.54, 3.68, 3.72, 3.54, 3.80, 2.31 and 2.32. Patients with common cavity deformity who underwent surgery using the traditional facial recess approach or transmastoid slotted labyrinthotomy approach had significantly better post-activation scores on the CAP, SIR and Meaningful Auditory Integration Scale/Infant-Toddler Meaningful Auditory Integration Scale, with no significant differences between the two approaches. CONCLUSION: The traditional facial recess approach can be successful, and several approaches may be used for electrode insertion and gusher control in patients with a severe deformity, particularly common cavity deformity and IP-III. A gusher was the most common intraoperative finding and occurred most often in patients with IP-III. Careful consideration of the type of electrode used is important.

Recurrent meningitis in children: etiologies, outcome, and lessons to learn.

PURPOSE: Recurrent meningitis in children is a rare condition. However, its early recognition is important in order to prevent serious complications. This study aims to review cases of recurrent meningitis in children. METHODS: This is a retrospective study that included children diagnosed with recurrent meningitis and who were followed at child neurology clinic at the Jordan University Hospital from January 2001 to June 2017. RESULTS: Thirteen patients were included (nine males and four females). Age of first episode of meningitis ranged from 2 months to 9.5 years. The delay in diagnosis of the underlying cause after the first episode ranged from 6 months to 2.5 years. Underlying causes included inner ear malformation in one patient, skull fractures in two, and dermal sinuses (thoracic spinal and occipital dermal sinus) in two patients. No identifiable cause was found in eight patients. Streptococcus pneumoniae was identified in four (31%) patients, Staphylococcus aureus in two (15%), and no organism was isolated in seven (54%). Three patients (23.1%) developed neurological sequel including developmental delay, limb spasticity, and epilepsy. Two patients had sensorineural hearing loss related to meningitis, and two patients had sensorineural hearing loss mostly related to their original disease. CONCLUSION: A detailed history, examination, and thorough investigations are necessary to determine the underlying cause of recurrent meningitis. In addition, in patients with positive CSF bacterial culture, finding the underlying etiology is very likely.