Ear Malformations Research Articles

Facial Nerve Anomalies as an Obscure Co-occurrence With External Ear Malformations: A Case Report

This study reports an infant with a rare triad of congenital facial palsy, bilateral aural atresia, and middle ear malformations. We highlight the audiological test battery in detail that led to identifying this obscure co-occurrence in a 6-month-old infant. The challenges associated with identifying such rare conditions, especially in infants, can be overcome only by incorporating a meticulous and vigilant approach. The infant was subjected to a series of subjective and objective audiological evaluations, through which rare asymmetric facial grimaces were vigilantly observed. This observation warranted radiologic investigation, which confirmed the suspicion that the anomaly may not be restricted to auditory structures alone. As facial nerve anomalies were confirmed, diversified recommendations, including speech, language, and swallow evaluation, were made apart from the auditory management. Hence in cases of external ear anomalies, although rare, it is essential to rule out facial nerve abnormalities as they can be a concealed problem.

Hearing-related quality of life assessment of pediatric cochlear implant users with inner ear malformations

ObjectivesTo assess the quality of life (QoL) in child and adolescent cochlear implant users with inner ear malformations (IEM) and to compare their outcomes to their cochlear implant using peers with normal inner ear structures. MethodsThe present sample consisted of 100 children (45 with IEM, 55 without IEM) and 100 adolescents (46 with IEM, 54 without IEM). The following QoL questionnaires were used to assess the hearing-related QoL: The Hearing Environments and Reflection on Quality of Life 26 (HEAR-QL-26 for children between 7 and 12 years of age) and HEAR-QL-28 (for adolescents between 13 and 18 years of age). Both questionnaires were based on a 5-points Likert scale from 0 to 4, with higher scores indicating a better perception of QoL. The scores were converted to percentage values (never = 100, almost never = 75, sometimes = 50, often = 25, almost always = 0). ResultsFor the patients with IEM, mean scores from the HEAR-QL-26 and HEAR-QL-28 were 50.4 (SD = 18.9) and 54.5 (SD = 19.6), respectively. For the patients without IEM, mean scores from the HEAR-QL-26 and HEAR-QL-28 were 72.7 (SD = 18.0) and 65.0 (SD = 19.1), respectively. For both child and adolescent subgroups, statistically significant differences were observed between QoL scores from patients with and without IEM (p < 0.001). There were no statistically significant effects of the malformation type on the QoL findings (p ≥ 0.05). ConclusionChild and adolescent cochlear implant users with IEM had significantly lower scores on validated HEAR-QL versions in comparison to their implanted peers without IEM.

A Prospective Study of Etiology and Auditory Profiles in Infants with Congenital Unilateral Sensorineural Hearing Loss.

Congenital unilateral sensorineural hearing loss (uSNHL) is associated with speech-language delays and academic difficulties. Yet, controversy exists in the choice of diagnosis and intervention methods. A cross-sectional prospective design was used to study hearing loss cause in twenty infants with congenital uSNHL consecutively recruited from a universal neonatal hearing-screening program. All normal-hearing ears showed ≤20 dB nHL auditory brainstem response (ABR) thresholds (ABRthrs). The impaired ear median ABRthr was 55 dB nHL, where 40% had no recordable ABRthr. None of the subjects tested positive for congenital cytomegalovirus (CMV) infection. Fourteen subjects agreed to participate in magnetic resonance imaging (MRI). Malformations were common for all degrees of uSNHL and found in 64% of all scans. Half of the MRIs demonstrated cochlear nerve aplasia or severe hypoplasia and 29% showed inner ear malformations. Impaired ear and normal-hearing ear ABR input/output functions on a group level for subjects with ABRthrs < 90 dB nHL were parallel shifted. A significant difference in interaural acoustic reflex thresholds (ARTs) existed. In congenital uSNHL, MRI is powerful in finding a possible hearing loss cause, while congenital CMV infection may be relatively uncommon. ABRs and ARTs indicated an absence of loudness recruitment, with implications for further research on hearing devices.

Association Between Maternal Exposure to SO2 and Congenital Ear Malformations in Offspring: A Population-Based Case-Control Study in Liaoning Province, China.

Objectives: To examine associations between maternal sulfur dioxide (SO2) exposure and congenital ear malformations risk in offspring. Methods: We surveyed 1676 cases with congenital ear malformations and 7950 controls from the Maternal and Child Health Certificate Registry of Liaoning Province between 2010 and 2015. SO2 concentrations were obtained from the Municipal Environment Protection Bureau of Liaoning Province. Multivariable logistic regression models and Restricted cubic splines (RCS) model were used to assess the aforementioned association. Results: There were significant associations between maternal SO2 exposure and congenital ear malformations risk during the 3 months before conception (OR Q4 vs. Q1 = 1.93, 95% CI = 1.43–2.59) and the 3 months after conception (OR Q4 vs. Q1 = 1.63, 95% CI = 1.22–2.18). Similar results were obtained in the analysis of single-month exposure windows, except for the third month before conception and the third month after conception. Moreover, these findings were broadly consistent across subgroups and robust in sensitivity analyses. There were non-linear dose-response associations between SO2 exposure and congenital ear malformations based on restricted cubic spline model analysis. Conclusion: Maternal SO2 exposure is associated with increased congenital ear malformations risk in offspring.

Retinoic acid signaling regulates late stages of semicircular canal morphogenesis and otolith maintenance in the zebrafish inner ear

The vitamin A derivative all-trans retinoic acid (RA) regulates early stages of inner ear development. As the early disruption of the RA pathway results in profound mispatterning of the developing inner ear, this confounds analyses of specific roles in later stages. Therefore, we used the temporal-specific exposure of all-trans RA or diethylaminobenzaldehyde to evaluate RA functions in late otic development. Perturbing late RA signaling causes behavioral defects analogous to those expected in larvae suffering from vestibular dysfunction. These larvae also demonstrate malformations of the semi-circular canals, as visualized through (a) use of the transgenic strain nkhspdmc12a, a fluorescent reporter expressed in otic epithelium; and (b) injection of the fluorescent lipophilic dye DiI. We also noted the altered expression of genes encoding ECM proteins or modifying enzymes. Other malformations of the inner ear observed in our work include the loss or reduced size of the utricular and saccular otoliths, suggesting a role for RA in otolith maintenance. Our work has identified a previously undescribed late phase of RA activity in otic development, demonstrating that vestibular defects observed in human patients in relation to perturbed RA signaling are not solely due to its early disruption in otic development.

Vestibular Imaging and Function in Patients With Inner Ear Malformation Presenting With Profound Hearing Loss.

ObjectiveVestibular impairment has been observed in patients with congenital hearing loss, but little is known about the vestibular anatomy and function of those in this group with inner ear malformations. This study aims to investigate the association between vestibulocochlear anatomy and vestibular function test results in children with inner ear malformations.Study DesignCase series with chart review.SettingPediatric patients with inner ear malformations presenting with bilateral profound hearing loss at a tertiary hospital from 1999 to 2017.MethodsEars were classified into subgroups based on anatomic abnormalities seen on computed tomography imaging. Cervical vestibular evoked myogenic potential (cVEMP), rotatory chair, and caloric test results were obtained and collated. Descriptive and inferential statistics were calculated.ResultsOf 82 ears, 29.3% had incomplete partition type II malformation, the most common type. The second-most common type was isolated vestibular organ anomaly (20.7%), which is not included in currently accepted categories. Most ears exhibited abnormal vestibular function. Abnormal vestibule volume was associated with a nonreactive cVEMP (P < .001). Radiologically abnormal lateral semicircular canals were associated with abnormal caloric and rotatory chair results (P < .001).ConclusionWith a relatively large number of cases of isolated vestibular organ anomaly not only in our study but also in previous publications, we suggest that this category be added to the subsets of inner ear malformations. Abnormal vestibule volume was significantly associated with a nonreactive cVEMP finding. The majority of patients with hearing loss secondary to inner ear malformations have abnormal vestibular function test results.

Craniofacial microsomia - more than a structural malformation.

To analyse the prevalence and distribution of craniofacial microsomia (CFM) cases in Finland and their most frequent comorbidities. The second aim was to analyse the patients' need for specialized healthcare services. Data were gathered from two complementary registers: The Register of Congenital Malformations and the Care Register for Social Welfare and Health Care (Hilmo) of the Finnish Institute for Health and Welfare (THL). The prevalence of CFM patients in Finland was 1:10057. They were evenly distributed across the five university hospital districts. Their most frequently used ICD-10 diagnosis codes were F40-48 (Neurotic, stress-related and somatoform disorders), 60% of patients in adolescent and adult psychiatry; Q67.0 (Facial asymmetry), 43% in plastic surgery; Z00.4 (General psychiatric examination, not elsewhere classified), 31% in child psychiatry; Z31.5 (Genetic counselling), 28% in clinical genetics and Q67.40 (Other congenital deformities of the skull, face and jaw, Hemifacial atrophy), 18% in dental, oral and maxillofacial diseases. Of the patients, 70% had had visits in clinical genetics, 60% in plastic surgery, 41% in dental, oral and maxillofacial diseases, 28% in adolescent/adult psychiatry and 21% in child psychiatry. The majority of the patients' plastic surgery visits were concentrated in one university hospital. Other services were mainly provided by patients' own hospital districts. Even though the majority of CFM patients' visits in specialized healthcare services are related to correction of facial asymmetry and ear malformations, the obvious need for psychiatric care was apparent in all age groups.

Effect of inner ear malformations on intraoperative ECAP thresholds and postoperative auditory performance.

ObjectivesThis study sought to characterize the influence of inner ear malformations (IEMs) on intraoperative electrically evoked compound action potential (ECAP) and auditory performance to better understand the underlying pathophysiology related to variabilities in cochlear implant (CI) outcomes that individuals with malformed cochlea may present.MethodsThe medical records of 222 ears implanted with Cochlear Nucleus CI were reviewed. Of the total, 64 ears had radiologic evidence of IEMs, and 158 ears were normal. Individuals with IEMs were grouped based on the severity of anomalies; 38 had mild IEMs (e.g., enlarged vestibular aqueduct, incomplete partition type II, etc.) and 26 had severe IEMs (e.g., cochlear nerve hypoplasia, common cavity, etc.). Intraoperative ECAP thresholds obtained via neural response telemetry (NRT) and the categories of auditory performance (CAP) scores measured at 12 months postoperative were compared and correlated.ResultsAbsent ECAP responses were more apparent in the IEM group. ECAP thresholds were significantly elevated in the severe IEM group, while the mild IEM group had ECAP thresholds comparable to the normal group. The mild IEM group achieved CAP scores similar to the normal control. Patients in the severe IEM group showed significantly lower CAP scores at 12 months postoperative. Significant negative relationships existed between ECAP thresholds and CAP scores obtained from all subjects.ConclusionMeasurable ECAP responses and NRT thresholds varied across groups. The inverse relationship between NRT thresholds and CAP scores may suggest that electrophysiological responses measured during surgery may potentially be indicative of postoperative performance in our CI population.Level of Evidence2b.

Assessment Protocol for Candidates for Bone-Anchored Hearing Devices.

Introduction The technology regarding bone-anchored hearing devices has been advancing. Nevertheless, complications are still often reported, which can impair treatment adherence and lead to discontinuation of use. There is a lack of studies conducted in tropical countries, where complications can be even greater, as well as standardized protocols for selection, indication and evaluation. Objective To characterize implanted patients from a Brazilian public institution and describe the medical and audiological assessment protocols to which they were submitted during the selection process and in the follow-up after surgery. Method An observational, cross-sectional study evaluating the medical records of patients with hearing loss and ear malformations and describing the care protocol through which they were treated. Results The medical records of 15 patients were reviewed: 6 received transcutaneous implants, and 9, percutaneous implants; 9 patients reported some type of skin lesion, 2 reported pain on the follow-up visit, and 3 had osseointegration failure. The time between surgery and activation ranged from 2 to 9 months. The median scores on the sentences, Sentences in Noise and Monosyllable tests were 100%, 60% and 80%, respectively. Conclusion It was possible to characterize the patients who received implants at the institution. The patients performed well in silence and had greater difficulty in noise. Even patients who had complications did not complain about the audibility and sound quality. It is essential to develop a model and to standardize the assessment and follow-up methods aimed at the benefit of users of bone-anchored hearing devices, as well as to enable the technico-scientific development in this field.

Cochlear base length as predictor for angular insertion depth in incomplete partition type 2 malformations

IntroductionThe preoperative determination of suitable electrode array lengths for cochlear implantation in inner ear malformations is a matter of debate. The choice is usually based on individual experience and the use of intraoperative probe electrodes. The purpose of this case series was to evaluate the applicability and precision of an angular insertion depth (AID) prediction method, based on a single measurement of the cochlear base length (CBL). MethodsWe retrospectively measured the CBL in preoperative computed tomography (CT) images in 10 ears (8 patients) with incomplete partition type 2 malformation. With the known electrode length (linear insertion depth, LID) the AID at full insertion was retrospectively predicted for each ear with a heuristic equation derived from non-malformed cochleae. Using the intra- or post-implantation cone beam CT images, the actual AID was assessed and compared. The deviations of the predicted from the actual insertion angles were quantified (clinical prediction error) to assess the precision of this single-measure estimation. ResultsElectrode arrays with 15 mm (n = 3), 19 mm (n = 2), 24 mm (n = 3), and 26 mm (n = 2) length were implanted. Postoperative AIDs ranged from 211° to 625°. Clinical AID prediction errors from −64° to 62° were observed with a mean of 0° (SD of 44°). In two ears with partial insertion of the electrode, the predicted AID was overestimated. The probe electrode was intraoperatively used in 9/10 cases. ConclusionThe analyzed method provides good predictions of the AID based on LID and CBL. It does not account for incomplete insertions, which lead to an overestimation of the AID. The probe electrode is useful and well established in clinical practice. The investigated method could be used for patient-specific electrode length selection in future patients.

Utility of unsupervised deep learning using a 3D variational autoencoder in detecting inner ear abnormalities on CT images

Background and purposeTo examine the diagnostic performance of unsupervised deep learning using a 3D variational autoencoder (VAE) for detecting and localizing inner ear abnormalities on CT images. MethodTemporal bone CT images of 6663 normal inner ears and 113 malformations were analyzed. For unsupervised learning, 113 images from both the malformation and normal cases were used as test data. Other normal images were used for training. A colored difference map representing differences between input and output images of 3D-VAE and the ratio of colored to total pixel numbers were calculated. Supervised learning was also investigated using a 3D deep residual network and all data were classified as normal or malformation using 10-fold cross-validation. ResultsFor unsupervised learning, a significant difference in the colored pixel ratio was seen between normal (0.00021 ± 0.00022) and malformation (0.00148 ± 0.00087) cases with an area under the curve of 0.99 (specificity = 92.0%, sensitivity = 99.1%). Upon evaluation of the difference map, abnormal regions were partially and not highlighted in 7% and 0% of the malformations, respectively. For supervised learning, which achieved 99.8% specificity and 90.3% sensitivity, a part of and no abnormal regions were highlighted on interpretation maps in 34% and 8% of the malformations, respectively. Abnormal regions were not highlighted in 4 malformation cases diagnosed as malformations and were highlighted in 6 cases misdiagnosed as normal. ConclusionsUnsupervised deep learning of 3D-VAE precisely detected inner ear malformations and localized abnormal regions. Supervised learning did not identify whole abnormal regions frequently and basis for diagnosis was sometimes unclear.

The Results of Cochlear Implantation in the Inner Ear Malformations.

Cochlear implants are arguably the most successful neural prosthesis today. Cochlear implantation has several difficulties in patients with internal ear anomalies. This study was performed to analyze intraoperative, postoperative findings, and auditory performance of 55 patients who had inner ear malformations and were treated with cochlear implants at Otorhinolaryngology Department of Çukurova University Hospital. Auditory performances were analyzed in 30 of 55 patients. Patients with cochlear anomalies were evaluated as group I, patients with vestibular malformation as group II, and patients with the normal bone labyrinth as group III. Listening progress profiles and meaningful auditory integration scale tests were used to determine performances. Comparison between the listening progress profiles test performance of the groups at 12th and 18th month of group I was significantly lower than other groups (P < .05) and reached at the same level after the 24th month. Comparison between the meaningful auditory integration scale test performance of groups at 24th and 36th month of group I was significantly lower than other groups (P < .05). Perilymph gusher was observed in 3 patients who had incomplete partition I malformation. Oozing was observed in 50% of incomplete partition II patients. Facial nerve traced a variant course in 4 of 55 patients and 6 patients had postoperative meningitis. Initially patients with inner ear anomalies showed that the level of language development was worse than patients with normal bone anatomy. However, it was shown that they both reached the same point as a result. Facial nerve anomaly and meningitis risk is higher in patients with inner ear malformations.

Landmarks for Proper Round Window Electrode Insertion in Cochlear Implantation.

This study aimed to evaluate the role of landmarks for proper round window electrode insertion in cochlear implantation surgery. This is a case series study. We included 150 patients undergoing cochlear implantation in a tertiary medical center during the period from January to December 2019. Patients with inner ear malformations or ossification or revision surgery were excluded. Three surgeons partici- pated in the study. During surgery, the round window electrode insertion was marked using 5 surgical landmarks: oval window, pyramid, fustis, round window membrane, and arborization of intracochlear blood vessels. Each surgeon reported on the identification of each landmark and its reliability for round window electrode insertion. Oval window and round window membrane were clearly seen by the 3 surgeons in all cases. Pyramid was seen in 94% of cases, fustis in 85%, and intracochlear wall in 90% of cases. The postoperative transorbital x-ray confirmed the intracochlear position of electrodes in all cases. Round window electrode insertion can be precisely performed using these 5 surgical landmarks in straight forwards cases as well as in difficult cases. These landmarks can also assist in teaching young surgeons, in a step-wise manner, how to properly do round window electrode insertion in cochlear implantation surgery.

The role of genetic factors in microtia: A systematic review

Background: Microtia is a congenital malformation of the outer ears caused by improper embryonic development. The origin of microtia and causes of its variations remain unknown. Because of the lack of clarity regarding the role of genetic variables in microtia, we conducted a systematic review to qualitatively identify the genes most important in the development of microtia to provide an up-to-date review. Methods: Using six search engines, we searched all published studies related to the genetic factors of isolated microtia and syndromic microtia. The identified publications were screened and selected based on inclusion and exclusion criteria by the authors and assessed for methodological quality using the Joanna Briggs Institute (JBI) critical appraisal tools. We found 40 studies, including 22 studies on syndromic microtia and 18 studies on isolated microtia. Data extraction of each study was arranged in tabulation for syndromic and isolated microtia. The extracted data were: first author’s surname, year of publication, country of origin, study design, sample characteristic and gene assessed. Results: After the data were extracted, analyzed, and reviewed, the most common gene suspected to be involved in isolated microtia was Homeobox A2 (HOXA2, 12.1%). Conversely, in syndromic microtia, the two most common genes supposed to play a role were Fibroblast Growth Factor 3 (FGF3, 47.2%) and Treacher–Collins–Franceschetti syndrome 1 (TCOF1, 30.2%). From the studies, the three most prevalent genes associated with microtia were HOXA2 (10%), FGF3 (8.4%), and TCOF1 (5.4%). In syndromic microtia, the most common mutation types were deletion in TCOF1 (46.9%) and missense and deletion in FGF3 (both 38%), and in isolated microtia, the most common mutation type was silent in HOXA2 (54.2%). Conclusions: In summary, genetic factors are involved in microtia; thus, molecular analysis is strongly advised. PROSPERO registration: CRD42021287294 (25/10/21).

Results and Quality of Life after Implantation of Active Middle Ear Implants.

The provision of implantable hearing aids represents an area with high development and innovation potential. On the one hand, this review article provides an overview of current indication criteria for the treatment with active middle ear implants. On the other hand, outcome parameters as well as functional results after implantation of active middle ear implants are demonstrated and discussed. The focus is mainly placed on audiological results as well as the subjective health status. "Patient Reported Outcome Measures" (PROMs) have become an integral part of the evaluation of hearing implant treatment. Due to low evidence level criteria, the study situation regarding audiological as well as subjective outcome parameters is not satisfactory. The lack of an international consensus on accepted outcome parameters makes a meta-analytical analysis of results immensely difficult. In the studies published to date, patients with sensorineural hearing loss and patients with conductive or mixed hearing loss offered better speech recognition after implantation of an active middle ear implant compared to conventional hearing aids. Current analyses show a significant improvement in general as well as hearing-specific quality of life after implantation of an active middle ear implant. To date, no validated, hearing-specific quality-of-life measurement instruments exist for assessing the success of fitting in children. Especially in children with complex malformations of the outer ear and the middle ear, excellent audiological results were shown. However, these results need to be substantiated by quality-of-life measurements in future.

Dissecting the Role of the Six1‐Associated Genes in Craniofacial Development and Disease

Genetic variants of SIX1, a transcription factor implicated in many cellular processes during craniofacial development, and of its co‐factor EYA1 underlie 50% of Branchio‐oto‐renal syndrome (BOR) cases. BOR is an autosomal dominant disorder characterized by various craniofacial defects, including malformed middle ear ossicles leading to conductive hearing loss. Interestingly, some BOR variants in SIX1 also underlie craniosynostosis (CRS) which indicates that SIX1 has a crucial role in craniofacial bone development. One important aspect of SIX1 function is that it interacts with co‐factors that can induce or repress its transcriptional activity. In this work, we expand our knowledge of the Six1 gene regulatory network with respect to craniofacial development. We first used a Six1 knockout mouse line to assess gene expression profiles of dissected E10.5 mandibular arches which give rise to the middle ear ossicles and lower jaw, via RNA‐sequencing. Our transcriptomic analysis led to the identification of 122 genes, including components of the FGF and WNT signaling pathways, known contributors to craniofacial bone development. In parallel, we used in vitro studies to characterize three novel co‐factors of Six1: Sobp, Mcrs1 and Pa2g4 that were recently identified in Xenopus. Our findings indicate that Sobp and Mcrs1 are bona fide Six1 co‐factors in mouse. We are now studying the genes identified in the RNA‐seq and the novel Six1 co‐factors using in vitro culture of mouse pre‐osteoblastic cells (MC3T3‐E1) to identify their role in bone formation. Altogether, our results identified novel Six1‐associated genes that are potential candidate genes for the unresolved cases of BOR and CRS.

Feasibility of day-case pediatric cochlear implantation.

Pediatric cochlear implantation is performed on an outpatient basis in an inconstant way. The aim of this study is to assess the feasibility of day-case pediatric cochlear implantation by determining the acceptability of outpatient-to-inpatient conversion rate (acceptability threshold of 5%) and to assess the safetyby comparing outpatient and inpatient postoperative events. We also want to identify conversion predictive factors. We conducted a monocentric retrospective study including 267 cases aged 6months to 18years who underwent unilateral cochlear implantation between 2016 and 2020. This population was divided into two groups: outpatient group (190 cases) and inpatient group (77 cases). Among the 190 cases scheduled as day surgery, 9 cases required conversion to conventional hospitalization which leads to an outpatient-to-inpatient conversion rate of 4.7%. Postoperative nausea and vomiting (PONV) were involved in all cases of conversion. Conversion predictive factors were the presence of an inner ear malformation at risk of gusher (OR 32.51, 95% CI [4.98-370.27], p 0.001) and the intraoperative administration of morphine (OR 8.52, 95% CI [1.38-86.84], p 0.035). There was no statistically significant difference in immediate postoperative complications (outpatient 14.2% vs inpatient 16.9% p 0.715), early-stage complications (outpatient 12.6% vs inpatient 10.4% p 0.812) and early-stage unplanned consultations (outpatient 4.7% vs inpatient 3.9% p 0.748) between outpatient and inpatient groups. Unplanned readmissions were found only in the outpatient group. Day-case pediatric cochlear implantation is a feasible and safe procedure even in infants. The outpatient-to-inpatient conversion rate of 4.7% is considered acceptable but requires anticipation of human and accommodation needs. No causes of conversion were life-threatening. The risk of postoperative complications and unplanned consultations are not influenced by the mode of hospitalization. Special attention should be paid to the prevention of PONV and the presence of inner ear malformations.

Clinical use of child-friendly video head impulse test in dizzy children

ObjectiveTo investigate the high-frequency vestibular functions using a child-friendly video head impulse test and to classify vestibular symptoms using a standard nomenclature guideline in dizzy children. Materials and methodsThe video head impulse test with a remote camera was used in this study. The data of 40 dizzy children (7.30 ± 4.75 years) were analyzed retrospectively. ResultsThe high-frequency vestibulo-ocular reflex gains of 14 (35%) dizzy children in the study group were reduced, whereas the vestibulo-ocular reflex gains of 26 (65%) dizzy children were normal. Two of them had a dramatic reduction in vestibulo-ocular reflex gains on their affected SCCs, but no corrective saccades as their gazes had not been fixated on the target at the onset of head impulses. In dizzy children, the most common cause was inner ear malformation (15%) and the most common vestibular symptom was unsteadiness (25%). ConclusionThe high-frequency vestibular function of the VOR in dizzy children, especially those suffering from IEM and unsteadiness, can be quickly screened using the vHIT device with the remote camera. However, clinicians should be careful during the interpretation of traces in the pediatric group.

Etiology of hearing loss affects auditory skill development and vocabulary development in pediatric cochlear implantation cases

Background Cochlear implantation (CI) is an effective treatment for severe-to-profound hearing loss patients and is currently used as the standard therapeutic option worldwide. However, the outcomes of CI vary among patients. Aims/Objectives This study aimed to clarify the clinical features for each etiological group as well as the effects of etiology on CI outcomes. Materials and methods We collected clinical information for 308 pediatric cochlear implant cases, including the etiology, hearing thresholds, age at CI, early auditory skill development, total development, monosyllable perception, speech intelligibility and vocabulary development in school age, and compared them for each etiology group. Results Among the 308 CI children registered for this survey, the most common etiology of hearing loss was genetic causes. The genetic etiology group showed the most favorable development after CI followed by the unknown etiology group, syndromic hearing loss group, congenital CMV infection group, inner ear malformation group, and cochlear nerve deficiency group. Conclusions and significance Our results clearly indicated that the etiology of HL affects not only early auditory skill development, but also vocabulary development in school age. The results of the present study will aid in more appropriate CI outcome assessment and in more appropriate intervention or habilitation programs.

Cochlear Nerve Deficiency in Pediatric Unilateral Hearing Loss and Asymmetric Hearing Loss

Introduction: The rates of cochlear nerve abnormalities and cochlear malformations in pediatric unilateral hearing loss (UHL) are conflicting in the literature, with important implications on management. The aim of this study was to investigate the incidence of cochlear nerve deficiency (CND) in pediatric subjects with UHL or asymmetric hearing loss (AHL). Methods: A retrospective chart review of pediatric subjects <18 years of age evaluated for UHL or AHL with fine-cut heavily T2-weighted magnetic resonance imaging (MRI) between January 2014 and October 2019 (n = 291) at a tertiary referral center was conducted. MRI brain and computed tomography temporal bone were reviewed for the presence of inner ear malformations and/or CND. Status of the ipsilateral cochlear nerve and inner ear was evaluated. Pure tone average (PTA) at 500, 1,000 and 2,000 Hz was assessed. Results: 204 subjects with UHL and 87 subjects with AHL were included. CND (aplasia or hypoplasia) was demonstrated in 61 pediatric subjects with UHL (29.9%) and 10 with AHL (11.5%). Ipsilateral cochlear malformations were noted in 25 subjects with UHL (12.3%) and 11 with AHL (12.6%), and ipsilateral vestibular malformations in 23 (11.3%) and 12 (13.8%) ears, respectively. Median PTA was statistically significantly higher in ears with CND (98.33) than ears with normal nerves (90.84). Discussion/Conclusion: Imaging demonstrated a high incidence of inner ear malformations, particularly CND, in pediatric subjects with UHL. Auditory findings indicated CND cannot be ruled out by thresholds alone as some CND ears did demonstrate measurable hearing. Radiologic evaluation by MRI should be performed in all patients within this population to guide counseling and management of hearing loss based on etiology, with implications on candidacy for cochlear implantation.