Vestibular Aqueduct Research Articles

Large Vestibular Aqueduct-Associated Symptoms: Endolymphatic Duct Blockage as a Surgical Treatment.

This study aimed to evaluate the effectiveness of endolymphatic duct blockage (EDB) on dizziness control in patients with a large vestibular aqueduct (LVA) and to evaluate its effect on hearing. This is a prospective nonrandomized study. Five adults and one child with dizziness and five children with progressive hearing loss were referred to our tertiary centers. The dizziness handicap inventory (DHI) and DHI-PC (dizziness handicap inventory-patient caregiver) questionnaires were used before and after surgery. All patients underwent a preoperative temporal bone HRCT scan and pure tone audiometry one day before surgery, then four and twelve months after surgery and at the last follow-up. The mean follow-up time was 5.6 years. Student's t-test was used to compare DHI/-PC results. The DHI scores were 44, 24, 84, 59 and 56 before surgery, respectively, for Patients 1 to 5. The DHI scores at four months was significantly different, i.e., 4, 6, 0, 7 and 18 (p = 0.001). No differences were found between 4 and 12 months. Patient 6 (child) had Trisomy 21; their DHI-PC score dropped from 38 (preoperative score) to 8 (postoperative score), showing no activity limitations; clinical evaluation showed the complete resolution of symptoms. We found no significant differences between hearing loss before the surgery and at 1 and 12 months post operation for four adult patients. Our fifth adult patient's hearing changed from severe to profound SNHL. For 5 out of 6 pediatric patients, preoperative PTA and mean ABG were 63 dB and 20 dB, respectively; postoperatively, they improved to 42 dB and 16 dB, respectively. The hearing loss level for the sixth pediatric patient dropped from moderate (PTA = 42 dB) to severe (PTA = 85 dB) due to an opening of the endolymphatic sac and a sudden leak of the endolymph. EDB, using two titanium clips, seems to be helpful for controlling vestibular symptoms and for stabilizing hearing or even to improve hearing in 82% of cases. Nevertheless, there is a risk of hearing worsening.

Aberrant Course of the Intratemporal Facial Nerve in Children with Congenital Hearing Loss.

Congenital facial nerve (FN) malformations are uncommon. Our aim is to determine the clinical and radiological features of FN malformations along with the associated cochlear and vestibular malformations. We conducted a retrospective study including children with a profound sensorineural hearing loss who were candidates for cochlear implantation. We evaluated the presence of FN malformations through temporal bone computed tomography scan and magnetic resonance imaging. We recorded an aberrant FN course in five out of 165 patients in a total of 9 ears. They consisted of a bifurcation of the mastoid segment, an anterior or posterior displacement of the labyrinthine segment and a hypoplasia of the geniculate ganglion. Associated inner ear malformations included vestibular aqueduct dilation, cochlear hypoplasia and total labyrinthine aplasia. We noted a bilateral agenesis of the cochlear nerve in three patients. Facial nerve malformations should be suspected in patients presenting a congenital hearing loss especially in association with other temporal bone malformations. Their pre-operative discovery is helpful in planning the surgical procedure.

Wideband acoustic immittance characteristics and machine learning-based diagnostic model for children with large vestibular aqueduct syndrome

Objective:This study was to investigate the wideband acoustic immittance（WAI） characteristics of children with large vestibular aqueduct syndrome（LVAS） and to construct a diagnostic model for LVAS based on WAI and machine learning（ML） techniques. Methods:We performed a retrospective analysis of the data from 38 children（76 ears） with LVAS and 44 children（88 ears） with normal hearing. The data included conventional audiological examination, temporal bone CT scan and WAI test. We performed statistical analysis and developed multivariate diagnostic models based on different ML techniques. Results:The two groups were balanced in terms of ear, gender, and age（P>0.05）. The wideband absorbance（WBA） of the LVAS group was significantly lower than that of the control group at 1 000-2 519 Hz, while the WBA of the LVAS group was significantly higher than that of the control group at 4 000-6 349 Hz（P<0.05）. WBA at 5 039 Hz under ambient pressure had a certain diagnostic value（AUC=0.767）. The multivariate diagnostic model had a high diagnostic value（AUC>0.8）, among which the KNN model performed the best（AUC=0.961）. Conclusion:The WAI characteristics of children with LVAS are significantly different from those of normal children. The diagnostic model based on WAI and ML techniques has high accuracy and reliability, and provides new ideas and methods for intelligent diagnosis of LVAS.

Does CISS MRI Reliably Depict the Endolymphatic Duct in Children with and without Vestibular Aqueduct Enlargement?

High-resolution CT is the mainstay for diagnosing an enlarged vestibular aqueduct (EVA), but MR imaging may be an appealing alternative, given its lack of ionizing radiation exposure. The purpose of this study was to determine how reliably MR imaging demonstrates the endolymphatic duct and endolymphatic duct enlargement in hearing-impaired children. We performed a retrospective review of temporal bone high-resolution CT and MR imaging of hearing-impaired children evaluated between 2017 and 2020. Vestibular aqueduct diameter was measured on high-resolution CT. The vestibular aqueducts were categorized as being enlarged (EVA+) or nonenlarged (EVA-) using the Cincinnati criteria. The endolymphatic ducts were assessed on axial high-resolution CISS MR imaging. We categorized endolymphatic duct visibility into the following: type 1 (not visible), type 2 (faintly visible), and type 3 (easily visible). Mixed-effect logistic regression was used to identify associations between endolymphatic duct visibility and EVA. Interreader agreement for the endolymphatic duct among 3 independent readers was assessed using the Fleiss κ statistic. In 196 ears from 98 children, endolymphatic duct visibility on MR imaging was type 1 in 74.0%, type 2 in 14.8%, and type 3 in 11.2%; 20.4% of ears were EVA+ on high-resolution CT. There was a significant association between EVA+ status and endolymphatic duct visibility (P < .01). Endolymphatic duct visibility was type 1 in 87.1%, type 2 in 12.8%, and type 3 in 0% of EVA- ears and type 1 in 22.5%, type 2 in 22.5%, and type 3 in 55.0% of EVA+ ears. The predicted probability of a type 3 endolymphatic duct being EVA+ was 0.997. There was almost perfect agreement among the 3 readers for distinguishing type 3 from type 1 or 2 endolymphatic ducts. CISS MR imaging substantially underdiagnoses EVA; however, when a type 3 endolymphatic duct is evident, there is a >99% likelihood of an EVA.

Association Between Vestibular Aqueduct Morphology and Meniere's Disease.

To investigate the relationship between vestibular aqueduct (VA) morphology and Meniere's disease (MD) using ultrahigh-resolution computed tomography (U-HRCT). Retrospective data were collected from 34 patients (40 ears) diagnosed with MD in our hospital who underwent temporal bone U-HRCT with isotropic 0.05-mm resolution, magnetic resonance with gadolinium-enhanced, and pure-tone audiometry; 34 age- and sex-matched controls (68 ears) who underwent U-HRCT were also included. VA patency was qualitatively classified as locally not shown (grade 1), locally faintly shown (grade 2), or clearly shown throughout (grade 3). The width of the outer orifice and VA length and angle were quantitatively measured. Differences in VA morphology between the MD and control groups were analyzed. The correlations between VA morphology and the degrees of hearing loss and endolymphatic hydrops (EH) were also analyzed. VA was classified as grades 1-3 in 11, 17, and 12 ears in the MD group and 5, 26, and 37 ears in the control group, respectively. The patency differed significantly between the groups (p < 0.01). The width of the outer orifice and length of VA were significantly smaller in the MD group than those in the control group (p < 0.05). Both VA patency and length were correlated with the degree of EH in the cochlea and the vestibule (p < 0.05). No difference was found between VA morphology and the degree of hearing loss (p > 0.05). The morphological characteristics of VA were found to be associated with the occurrence of MD and the degree of EH. 4 Laryngoscope, 134:3349-3354, 2024.

Enlarged vestibular aqueduct as a cause of postneonatal deafness

IntroductionThe enlarged vestibular aqueduct (EVA) is the most frequent malformation of the inner ear associated with sensorineural hearing loss (5–15%). It exists when the diameter in imaging tests is greater than 1.5 mm at its midpoint. The association between hearing loss and EVA has been described in a syndromic and non-syndromic manner. It can appear as a familial or isolated form and the audiological profile is highly variable. The gene responsible for sensorineural hearing loss associated with EVA is located in the same region described for Pendred syndrome, where the SCL26A4 gene is located. ObjectiveTo describe a series of children diagnosed with EVA in order to study their clinical and audiological characteristics, as well as the associated genetic and vestibular alterations. MethodRetrospective study of data collection of children diagnosed with EVA, from April 2014 to February 2023. ResultsOf the 17 cases, 12 were male and 5 were female. 5 of them were unilateral and 12 bilateral. In 5 cases, a cranial traumatism triggered the hearing loss. Genetic alterations were detected in 3 cases: 2 mutations in the SCL26A4 gene and 1 mutation in the MCT1 gene. 13 patients (76.5%) were rehabilitated with hearing aids and 9 of them required cochlear implantation. DiscussionThe clinical importance of AVD lies in the fact that it is a frequent finding in the context of postneonatal hearing loss. It is convenient to have a high suspicion to diagnose it with imaging tests, to monitor its evolution, and to rehabilitate early.

Assessing the optimal MRI descriptors to diagnose Ménière’s disease and the added value of analysing the vestibular aqueduct

ObjectivesTo evaluate the diagnostic performance and reliability of MRI descriptors used for the detection of Ménière’s disease (MD) on delayed post-gadolinium MRI. To determine which combination of descriptors should be optimally applied and whether analysis of the vestibular aqueduct (VA) contributes to the diagnosis.Materials and methodsThis retrospective single centre case-control study evaluated delayed post-gadolinium MRI of patients with Ménièriform symptoms examined consecutively between Dec 2017 and March 2023. Two observers evaluated 17 MRI descriptors of MD and quantified perilymphatic enhancement (PLE) in the cochlea. Definite MD ears according to the 2015 Barany Society criteria were compared to control ears. Cohen’s kappa and diagnostic odds ratio (DORs) were calculated for each descriptor. Forward stepwise logistic regression determined which combination of MRI descriptors would best predict MD ears, and the area under the receiver operating characteristic curve for this model was measured.ResultsA total of 227 patients (mean age 48.3 ± 14.6, 99 men) with 96 definite MD and 78 control ears were evaluated. The presence of saccular abnormality (absent, as large as or confluent with the utricle) performed best with a DOR of 292.6 (95% confidence interval (CI), 38.305–2235.058). All VA descriptors demonstrated excellent reliability and with DORs of 7.761 (95% CI, 3.517–17.125) to 18.1 (95% CI, 8.445–39.170). Combining these saccular abnormalities with asymmetric cochlear PLE and an incompletely visualised VA correctly classified 90.2% of cases (sensitivity 84.4%, specificity 97.4%, AUC 0.938).ConclusionEither absent, enlarged or confluent saccules are the best predictors of MD. Incomplete visualisation of the VA adds value to the diagnosis.Clinical relevance statementA number of different MRI descriptors have been proposed for the diagnosis of Ménière’s disease, but by establishing the optimally performing MRI features and highlighting new useful descriptors, there is an opportunity to improve the diagnostic performance of Ménière’s disease imaging.Key Points• A comprehensive range of existing and novel vestibular aqueduct delayed post-gadolinium MRI descriptors were compared for their diagnostic performance in Ménière’s disease.• Saccular abnormality (absent, confluent with or larger than the utricle) is a reliable descriptor and is the optimal individual MRI predictor of Ménière’s disease.• The presence of this saccule descriptor or asymmetric perilymphatic enhancement and incomplete vestibular aqueduct visualisation will optimise the MRI diagnosis of Ménière’s disease.

A Long-Term Follow-Up Study on the Auditory Performance and Speech Intelligibility of Mandarin-Speaking Prelingually Deaf Children With Isolated Large Vestibular Aqueduct Syndrome After Cochlear Implantation.

The purpose of this study was to evaluate the auditory performance and speech perception of 104 children with isolated large vestibular aqueduct syndrome (LVAS) and 523 children with no inner ear malformation (IEM) for 5 years after cochlear implantation, in order to explore whether isolated LVAS can affect the long-term hearing and speech rehabilitation of deaf children after cochlear implantation. A cohort study was established consisting of 627 children who underwent cochlear implantation at Beijing Tongren Hospital from 1999 to 2016. The children were examined at 0, 6, 12, 24, 36, 48, and 60 months after cochlear implantation to assess their auditory performance and speech perception using the Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) questionnaires. The CAP scores of the isolated LVAS group increased significantly during the baseline to the 24th month, after which they gradually rose until reaching the plateau during the 24th to the 60th month. The CAP scores of the non-IEM group increased significantly during the baseline to the 36th month and then increased steadily. The SIR scores went up significantly during the baseline to the 48th month, and increased in a gradual manner in other stages of isolated LVAS evaluation. In comparison, The SIR scores of non-IEM group grew remarkably from the baseline to the 60th month. There were no significant differences in the CAP or SIR scores between isolated LVAS and non-IEM groups in each stage of evaluation, with the only exception being the CAP score at baseline month after cochlear implantation. The CAP and SIR questionnaires are helpful tools for quantifying the early hearing and speech skills of younger prelingually deafened cochlear implant recipients. This long-term follow-up study shows that the speech and hearing development of children in isolated LVAS and non-IEM groups follow similar patterns, and isolated LVAS does not affect the long-term rehabilitation of deaf children after cochlear implantation.

A novel intronic variant causing aberrant splicing identified in two deaf Chinese siblings with enlarged vestibular aqueducts.

We aimed to evaluate the genotype-phenotype relationship in two Chinese family members with enlarged vestibular aqueduct (EVA). We collected blood samples and clinical data from each pedigree family member. Genomic DNA was isolated from peripheral leukocytes using standard methods. Targeted next-generation sequencing and Sanger sequencing were performed to find the pathogenic mutation in this family. Minigene assays were used to verify whether the novel intronic mutation SLC26A4c.765+4A>G influenced mRNA splicing. Hearing loss in the patients with EVA was diagnosed using auditory tests and imaging examinations. Two pathogenic mutations, c.765+4A>G and c.919-2A>G were detected in SLC26A4. Invitro minigene analysis confirmed that c.765+4A>G variant could cause aberrant splicing, resulting in skipping over exon 6. The SLC26A4c.765+4A>G mutation is the causative variant in the Chinese family with EVA. Particular attention should be paid to intronic variants.

A rare clinical case of a labyrinthine lesion: an endolymphatic sac tumor

Endolymphatic sac tumors are rare neoplasms originating from the endolymphatic epithelium of the intraosseous part of the endolymphatic duct and sac, typically characterized by slow growth and local destructive changes. We present a case of an endolymphatic sac tumor in a 28-year-old man who consulted an otoneurologist with complaints of progressive hearing loss and dizziness attacks and was referred for a CT scan of the temporal bones and MRI of the inner ear with delayed contrast enhancement. The data of otoneurological and radiological examinations before and after surgical treatment and the results of surgical treatment with histological verification of the tumor are presented. The objective of this case presentation is to demonstrate the usefulness of CT and MRI methods in detecting an endolymphatic sac tumor, to compare the results of otoneurological and radiological examinations and intraoperative and histological data followed by surgery. Radiological examination revealed a neoplasm of the right temporal bone with typical imaging characteristics of endolymphatic sac tumor. Surgery was performed, the mass was removed completely, and the endolymphatic sac tumor was histologically verified. Radiologic presentation includes a typically located area of bone destruction in the petrous part of the temporal bone in the area of the vestibular aqueduct, possibly with the spread of the tumor into the cerebellopontine angle, with a heterogeneous structure, with uneven contrast enhancement. Due to the rarity of this pathology, diagnosis in the early stages is often difficult, and for the correct interpretation of radiologic findings in patients with hearing loss and dizziness, knowledge of the normal anatomy of the temporal bone and awareness of rare variants of its lesions are of key importance. Timely examination of patients with suspected temporal bone lesions and correct diagnosis are the key to successful treatment and maintaining the quality of life in this group of patients.

Cochlear Implantation in Inner Ear Malformations

Introduction: Cochlear Implantation (CI) has proven to be an effective treatment for severe bilateral Sensorineural Hearing Loss (SNHL). Inner ear malformation is a rare anomaly and occurs in approximately 20% of cases with congenital SNHL. There are particular challenges in the implantation of malformed cochleae, such as in cases of facial nerve anomalies, Cerebrospinal Fluid (CSF) leaks 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: Between 2018 and 2022, 9 patients with inner ear malformations were implanted in our department and completed at least 1 year of follow-up. The age range was between 2 years and 4 months and 5 years (average, 3.36 yr). Auditory performance, receptive and expressive language skills, and production and use of speech were evaluated preoperatively and at least 1 year after implantation. Results: In the study group, the most common malformation was an isolated Enlarged Vestibular Aqueduct (EVA) (55,5%). 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. Conclusion: Based on these findings, cochlear implantation is surgically feasible in patients with common cavity, IP types I and II, and EVA. The surgeon should be ready to make modifications in the surgical approach because of the abnormal course of the facial nerve and be ready to produce special precautions to cerebrospinal fluid gusher. Patients with EVA were the best performers in terms of auditory-verbal skills.

Study of the factors related to air-bone gap in enlarged vestibular aqueduct

Background Over half of patients with enlarged vestibular aqueducts (EVA) will have an air-bonr gap (ABG), however, current research on audiology has focused on the influencing factors of air-conducted. Objective To retrospectively analyse the influencing factors and clinical manifestations of the bone-conduction threshold and ABG in patients with EVA. Materials and methods We included 286 patients with EVA; among them, 126 had full SLC26A4 gene sequence results. We performed a descriptive analysis of the bone-conduction threshold and explored the effect of age. Finally, we analyzed the relationship of ABG and SLC26A4 genes with the degree of vestibular aqueduct (VA) enlargement. Results Among 555 ears, 312 (57.8%) ears had ABG; approximately 94% of the patients’ bone-conduction hearing is almost completely lost at frequencies of 2 and 4 kHz. There was no linear correlation between age and bone-conduction threshold (p > 0.05). ABG did not significantly differ according to the degree of VA enlargement and number of SLC26A4 allele mutations (p > 0.05). Conclusions and significance Among patients with EVA, ABG is mainly produced at low frequencies and is not significantly correlated with age, size of the VA opening or SLC26A4 genes, which could be attributed to the biomechanical effects.

Клинический случай пациента с расширенным водопроводом преддверия

Enlarged vestibular aqueduct is an anomaly of the inner ear development, which is manifested by sensorineural hearing loss and vestibular disorders most often at an early age. It is not uncommon for this pathology to have a conductive component of hearing loss on audiometry. In such cases, the dilated vestibule syndrome masquerades as middle ear disease, particularly otosclerosis. There are several theories of the origin of the conductive component of hearing loss in this developmental anomaly, the main ones are discussed in this article. Multispiral computed tomography (MSCT) of temporal bones, which an otorhinolaryngologist should be able to evaluate independently, paying attention to all structures of the temporal bone, including an increase in the anteroposterior size of the vestibular aqueduct of more than 1.5 mm, allows detecting an enlarged vestibular aqueduct at the stage of preoperative examination of the patient. Timely detection of the enlarged vestibular aqueduct will allow avoiding unnecessary surgical intervention and associated complications in the form of gusher syndrome and vestibular disorders.

Exonic Deletions and Deep Intronic Variants of the SLC26A4 Gene Contribute to the Genetic Diagnosis of Unsolved Patients With Enlarged Vestibular Aqueduct

Enlarged vestibular aqueduct (EVA) is a frequently occurring inner ear malformation that associates with sensorineural hearing loss (SNHL), with SLC26A4 being the responsible gene. Based on multiplex PCR enrichment and sequencing of the exonic and flanking regions of the SLC26A4 gene, we developed a panel specifically for EVA and found that up to 95% of EVA patients in our Chinese cohorts carried biallelic SLC26A4 pathogenic variants (M2). In this study, we tried to investigate the genetic etiology of 13 previously undiagnosed EVA patients with monoallelic (M1) or none (M0) SLC26A4 variant using a stepwise approach, including copy number variation (CNV) analysis of multiplex PCR enrichment and next‐generation sequencing data, single‐molecule real‐time (SMRT) sequencing of the whole SLC26A4 gene, whole exome sequencing (WES), and whole genome sequencing (WGS). CNV analysis revealed deletions in Exons 1–3, Exons 5–6, and Exons 9–10 of the SLC26A4 gene in seven patients, and SMRT sequencing identified the same heterozygous deep intronic variant (NM_000441.2:c.304+941C&gt;T) in two patients, resulting in a final diagnosis in 9/13 patients. Notably, the variants of Exons 9–10 deletion and c.304+941C&gt;T have not been reported previously. We further showed that the variant c.304+941C&gt;T led to the exonization of partial AluSz6 element (126 bp) where the variant is located through sequencing of the mRNA extracted from the blood of a heterozygous variant carrier. In conclusion, our stepwise approach improved the diagnosis rate of EVA, expanded the mutational spectrum of the SLC26A4 gene, and highlighted the contribution of exonic deletions and deep intronic variants to EVA.

Hyperbaric oxygen therapy for sudden hearing loss in enlarged vestibular aqueduct syndrome: A case report and review of literature

Hyperbaric oxygen therapy for sudden hearing loss in enlarged vestibular aqueduct syndrome: A case report and review of literature

Enlarged Vestibular Aqueduct and Associated Inner Ear Malformations: Hearing Loss Prognostic Factors and Data Modeling from an International Cohort.

There is a need to operationalize existing clinical data to support precision medicine in progressive hearing loss (HL). By utilizing enlarged vestibular aqueduct (EVA) and its associated inner ear abnormalities as an exemplar, we model data from a large international cohort, confirm prognostic factors for HL, and explore the potential to generate a prediction model to optimize current management paradigms. An international retrospective cohort study. Regression analyses were utilized to model frequency-specific HL and identify prognostic factors for baseline average HL severity and progression. Elastic-net regression and machine learning (ML) techniques were utilized to predict future average HL progression based upon routinely measurable clinical, genetic, and radiological data. Higher frequencies of hearing were lost more severely. Prognostic factors for HL were the presence of incomplete partition type 2 (coefficient 12.95 dB, P=.011, 95% CI 3.0-22 dB) and presence of sac signal heterogeneity (P=.009, 95% CI 0.062-0.429) on magnetic resonance imaging. Elastic-net regression outperformed the ML algorithms (R2 0.32, mean absolute error 11.05 dB) with coefficients for baseline average hearing level and the presence of sac heterogeneity contributing the most to prediction outcomes. Incomplete partition type 2 and endolymphatic sac signal heterogeneity phenotypes should be monitored closely for hearing deterioration and need for early audiological rehabilitation/cochlear implant. Preliminary prediction models have been generated using routinely collected health data in EVA. This study showcases how international collaborative research can use exemplar techniques to improve precision medicine in relatively rare disease entities.

Applications of visualizing cochlear basal turn in cochlear implantation.

To report a reliable method in obtaining optimal cochlear basal turn and cross-section (c/s) of internal auditory canal (IAC) supporting Cochlear implantation (CI) procedure. Computer tomography (CT) and magnetic resonance image (MRI) scans of potential CI candidates from 2018 to 2022 from the tertiary center were considered for analysis. Slicer software was used in three-dimensional (3D) segmentation of inner ear and for capturing the cochlear basal turn. A total of 1932 head scans were made available for the analysis and out of which 1866 scans had normal anatomy (NA) inner ear. Incomplete partition (IP) type-I was identified in 19 ears, IP type-II in 27 ears, IP type-III in 6 ears, cochlear hypoplasia (CH) type-I in 6 ears, CH type-II in 1 ear, CH type-III in 3 ears, and CH type-IV is 3 ears, and enlarged vestibular aqueduct syndrome in 1 ear. 3D segmented inner ear helped in successfully obtaining the cochlear basal turn and the c/s of IAC in all anatomical types. Time taken to capture the cochlear basal turn with the help of 3D segmented inner ear was <1 min. Within the NA category, five cases showed scalar ossification, and its extent was identified in the cochlear basal turn. The identification and the extent of ossification in the scala tympani, shape of the basal turn, and the cochlear size measurement in cochlear basal turn has high clinical relevance as this helps in surgical planning and in choosing appropriate electrode length. Level of evidence: Level 2 to the best of our understanding.

Study on characteristics of wideband acoustic immittance in patients with Inner Ear Malformations

ObjectiveTo compare the differences in wideband absorbance and the resonance frequency (RF) between patients with inner ear malformations and normal control, and to explore the auditory diagnostic value of wideband acoustic immittance (WAI). MethodsA total of 38 patients (59 ears) with enlarged vestibular aqueduct (EVA), 13 patients (14 ears) with incomplete partition type I (IP–I) and 13 patients (26 ears) with incomplete partition type II (IP-II) were included. 50 normal control (100 ears). All subjects underwent WAI tests to compare the absorbance configuration and resonance frequency. ResultsAll the group showed lower absorbance at ambient pressure than at peak pressure in certain frequencies under 2000Hz. Under 1000Hz, the absorbance of EVA was higher than that of other groups. The average absorbance and highest absorbance of IP-I were the lowest(P＜0.05). However, IP-II and normal group had similarity on some characteristics. The three IEM groups mainly different at low and high frequencies, but not at medium frequencies. The highest absorbance of all the groups were appeared around 3000Hz. The RF of all the groups from low to high were EVA＜IP-II＜normal control＜IP-I, and the lowest was EVA(P＜0.05). ConclusionInner ear malformations can affect energy absorbance and RF. WAI is sensitive and non-invasive to provide useful information about inner ear status and facilitate detection of ear pathology.

Characteristics of vestibular-evoked myogenic potentials in children with vestibular malformation and severe sensorineural hearing loss

BackgroundWith the increasing clinical focus on the safety of bilateral cochlear implantation (CI) and the potential risk of bilateral vestibular dysfunction, evaluating vestibular end-organ function in patients with vestibular malformations with accompanying abnormalities has been strongly recommended. ObjectivesTo identify the vestibular-evoked myogenic potential (VEMP) values among children with sensorineural hearing loss (SNHL) with vestibular malformation and assess the effectiveness of VEMP testing for inner ear malformations (IEM) diagnosis. MethodsThis study included 96 children (192 ears), including those with vestibular malformations (48 ears), large vestibular aqueduct syndrome (LVAS) (50 ears), and SNHL without IEM (94 ears; control group). All groups underwent ocular and cervical VEMP (oVEMP and cVEMP, respectively) testing. The response rates, VEMP parameters, and wave characteristics were compared. ResultsThe cVEMP response rates were 37.5 %, 64 %, and 58.51 % and the oVEMP response rates were 42.86 %, 78.95 %, and 77.27 % in the vestibular malformation, LVAS, and control groups, respectively, and significantly differed between groups (cVEMP: X2 = 18.228, P<0.001) (oVEMP: X2 = 7.528, P = 0.023). Significant inter-group differences were observed for the cVEMP and oVEMP latency and amplitude (P < 0.05). The LVAS group's waveform exhibited a prolonged latency and increased amplitude compared with that of the other groups. ConclusionPatients with SNHL were highly susceptible to otolith dysfunction, regardless of comorbid vestibular malformation presence. Measuring VEMPs is an effective and rapid evaluation technique for vestibular function and could provide a basis for vestibular rehabilitation training.

Analysis of 59 cases of large vestibular aqueduct syndrome SLC26A4gene mutation frequency and new mutation sites

Objective:To study the frequency of SLC26A4 gene mutation sites in children with enlarged vestibular aqueduct deafness in Yunnan, report the new mutation sites of SLC26A4 gene, further clarify the mutation spectrum of SLC26A4gene, and explore the association between biallelic and monoallelic mutations of SLC26A4 gene and CT phenotype of inner ear, so as to provide basis for clinical and genetic diagnosis of deafness. Methods:Review the results of temporal bone CT examination of 390 children after cochlear implantation in the Department of Otolaryngology, Kunming Children's Hospital from August 2016 to September 2021. Sanger sequencing of SLC26A4 gene was performed in 59 children with enlarged vestibular aqueduct. According to the genetic test results, the children who underwent temporal bone CT examination were divided into two groups: SLC26A4 biallelic mutation group（homozygous mutation and compound heterozygous mutation）, monoallelic mutation group, and the association with inner ear CT phenotype was analyzed, and the new sites were summarized and analyzed. Results:The c.919-2a>g mutation was the most common mutation in children with enlarged vestibular aqueduct with SLC26A4 gene mutation. Three new variants of SLC26A4 gene were found; CT examination combined with genetic testing found that a part of children with enlarged vestibular aqueduct was associated with SLC26A4 monoallelic mutation or no SLC26A4 gene mutation was detected. Further research is needed to investigate the involvement of other pathogenic factors in the pathogenesis of EVA.