Large vestibular aqueduct syndrome (LVAS) is one of common non-syndromic hearing disorders. With the rapid development of medical imaging, audiology, molecular biology, genetics, cochlear implant surgery, we have made remarkable achievements in the diagnosis and treatment of large vestibular aqueduct syndrome. This article reviewed related researches of the large vestibular aqueduct syndrome.
Cochlear Implants ; Hearing Disorders ; genetics ; Humans ; Vestibular Aqueduct ; abnormalities ; Vestibular Diseases ; genetics

A ten-year-old boy with bilateral moderate sensorineural hearing loss underwent computerized tomographic (CT) imaging (GE Brightspeed, Wisconsin, USA) of the temporal bone as part of the work-up to determine the etiology of his condition. The formal radiologic interpretation of the scan stated that the vestibular aqueducts were not enlarged. However, independent review of the axial CT images appeared to indicate the presence of enlarged vestibular aqueducts. (Figure 1) This can be contrasted with a scan from another patient with no evidence of sensorineural hearing loss. (Figure 2) What can explain the discrepancy between the two? If simple visual inspection of the vestibular aqueduct (VA) can lead to conflicting interpretations, then what radiographic parameters can be used to resolve the issue? Is there a more objective means of determining the presence of a clinically significant vestibular aqueduct enlargement? In 1978, Valvasorri and Clemis1 first described an association between congenital sensorineural hearing loss and an abnormality in vestibular aqueduct anatomy which they labelled as the “large vestibular aqueduct syndrome.” In this landmark study that utilized hypocycloidal polytomographic temporal bone studies, they proposed that a vestibular aqueduct is enlarged when its midpoint diameter is greater than 1.5 mm. Although this parameter is generally considered to be the defining characteristic of the condition, one must realize that this measurement was based on less accurate imaging technology and measurement tools. Contemporary studies utilize high-resolution CT imaging with digital workstation measurement software to evaluate vestibular aqueduct anatomy. Currently, the two most commonly used radiographic parameters are the VA midpoint (MP) width and the VA opercular (OP) width. (Figure 3) More recently, Boston et al.2 in 2007 published normative values for these parameters based on a study population of 73 children without known sensorineural hearing loss. They considered a vestibular aqueduct enlarged when one or both of the measured widths were above the 95th percentile of the normal study group measurements. On this basis, a VA midpoint width of >0.9 mm and/or a VA opercular width of >1.9 mm was the criteria established to define an enlarged vestibular aqueduct. The patient’s measured vestibular aqueduct midpoint width on the right was 2.1 mm, while the vestibular aqueduct opercular width was 2.9 mm. (Figure 4) These measurements, when evaluated against either the original Valvassori criteria or the newer criteria of Boston et al., confirm what was visually apparent– the presence of a clinically significant enlargement of the vestibular aqueduct as the etiology of the patient’s sensorineural hearing loss.
Human ; Male ; Child ; Vestibular Aqueduct-etiology ; Temporal Bone-radiology ; Tomography Scanners, X-Ray Computed ; Hearing Loss, Sensorineural ; Congenital Abnormalities ;

OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with congenital deafness pedigree in conjunct with enlarged vestibular aqueduct. METHODS: Whole-exome sequencing was carried out for the proband to analyze the genes associated with hereditary deafness. Candidate variant was verified by Sanger sequencing of the proband's parents and her younger brother. RESULTS: The proband was found to harbor compound heterozygous variants including c.748dupG (p.Asp250Glyfs*30Asn) (pathogenic, PVS1+PM2+PP4) and c.879C>A (p.Ser293Arg) (likely pathogenic, PM2+PM3+PP1+PP4) of the FOXI1 gene, which has been associated with enlarged vestibular aqueduct (OMIM 600791). Both variants were unreported previously. The variants were respectively inherited from proband's parents whom had normal hearing. Her younger brother was heterozygous for the c.748dupG variant but also had normal hearing. CONCLUSION The compound heterozygous variants of the FOXI1 gene probably underlay the pathogenicity of congenital deafness and enlarged vestibular aqueduct in the proband. The co-segregation of the two variants with the hearing loss has facilitated genetic counseling and prenatal diagnosis for this pedigree.
China ; Deafness/genetics* ; Female ; Forkhead Transcription Factors/genetics* ; Hearing Loss, Sensorineural ; Humans ; Male ; Mutation ; Pedigree ; Pregnancy ; Vestibular Aqueduct/abnormalities*

OBJECTIVE: This study is to investigate the clinical materials of in-patients with the large vestibular aqueduct syndrome (LVAS), and explore the feature, diagnosis and treatment measures of the disease. METHOD: A retrospective review was conducted including the medical history, audiological examinations, vestibular function examinations, imaging examinations and treatment methods of 44 in patients (87 ears) suffering LVAS admitted to our hospital in the past 4 years(from 2008 to 2012). RESULT: ln the 44 in patients, there were 24 male cases and 20 female cases, and the male-female ratio was 1.2 :1. The average of the onset age was 3.39 years. Five cases (11. 36%) had related familial history. The profound hearing loss was found in 67 ears (77.01%), and the severe hearing loss was found in 20 ears (22.99%). After systemic treatment,the hearing of 38 ears improved effectively,but that of 49 ears did not improve obviously. The analysis found that patients suffering sudden hearing loss got better curative effect than those with progressive hearing loss. Patients received combined drug therapy improving arterial circulation as well as venous reflux got better therapeutic effect. There was a significant difference on effect between the patients with course of treatment more than 7 days and those less than 7 days. There was no significant correlation between therapeutic effect and other factors. CONCLUSION In part of LVAS patients,the hearing level can be effectively improved through a standard internal medicine treatment. We can improve the personalized and standardized treatment strategy for this disease through analysis of diagnosis and treatment of in-patients with complete clinical data.
Adolescent ; Adult ; Child ; Child, Preschool ; Female ; Hearing Loss, Sensorineural ; diagnosis ; therapy ; Humans ; Infant ; Inpatients ; Male ; Vestibular Aqueduct ; abnormalities ; Vestibular Diseases ; diagnosis ; therapy ; Young Adult

OBJECTIVE: To analyse the clinical audiological significance in the diagnosis of large vestibular aqueduct syndrome (LVAS) by the auditory brain stem response (ABR) testing. METHOD: Patients with sensorineural hearing loss were examined by temporal bone CT scanning from January, 2008 to September, 2009. The result of CT scanning of 70 cases inner ear malformation were analysed. Patients were divided into two groups, LVAS group including 38 cases (76 ears) and other inner ear malformation group including 32 cases (62 ears). All patient accepted clinical audiology analysis and auditory brainstem response (ABR) test. RESULT: Twenty-four cases (41 ears) of LVAS group were detected with ASNR in 2 3 cm by the ABR testing, the positive rate was 54%, while ASNR was not detected in patients of other inner ear malformations group. There was significant differences (P=0.01) of the ASNR between two groups. CONCLUSION There is high incidence of LVAS on the patients with non-syndromic deafness. ASNR by ABR testing could help diagnosing the LVAS.
Child ; Child, Preschool ; Ear, Inner ; abnormalities ; Evoked Potentials, Auditory, Brain Stem ; Female ; Hearing Loss, Sensorineural ; diagnosis ; physiopathology ; Humans ; Infant ; Infant, Newborn ; Male ; Syndrome ; Vestibular Aqueduct ; abnormalities

OBJECTIVE: To investigate imaging and audiology features of temporal bone and analyze the classification and prevalence of inner ear abnormalities in children with sensorineural hearing loss. METHOD: Children who were diagnosed with sensorineural hearing loss were examined by high resolution CT and the inner ear fluid of MRI. And each chart was retrospectively reviewed to determine the imaging and audiology features. RESULT: There were 125 patients(232 ears) found with inner ear malformation in 590 children with SNHL. About 21.71% of the inner ear malformation occurred in severe and profound hearing loss ears, and 12.85% occurred in r moderate hearing loss ears. The inner ear malformation rate in normal hearing ears were 13.59%. CONCLUSION CT and MRI examinations of temporal bone are important diagnostic tools to indentify inner ear malformations. Inner ear malformations are almost bilateral and hearing loss are profoud. Cochleo-vestibular malformations and large vestibular aqueduct are the 2 most frequent deformities. Among the children with SNHL, deformity rate in the severe and profound hearing loss ears is higher than that in moderate hearing loss ear. Inner ear malformations can exist in people with normal hearing.
Audiology ; Child ; Ear, Inner ; abnormalities ; Hearing Loss, Sensorineural ; congenital ; pathology ; Humans ; Magnetic Resonance Imaging ; Prevalence ; Retrospective Studies ; Temporal Bone ; Tomography, X-Ray Computed ; Vestibular Aqueduct ; abnormalities

OBJECTIVE: To study the molecular pathogenesis of SLC26A4 mutations associated with inner ear malformations including large vestibular aqueduct syndrome (LVAS), Mondini dysplasia and inner ear malformations but not accompanied with LVAS. METHOD: DNA sample and clinical material were obtained from 14 sporadic LVAS probands, six Mondini dysplasia probands and seven inner ear malformations excluding IVAS probands. SLC26A4 gene mutation was analyzed by direct sequencing for its 20 coding exons. GJB2 gene and also mt12SrRNA were analyzed by direct sequencing. RESULT: In 14 cases of LVAS, two mutations were detected in 12 patients (85.7%, either homozygous or compound heterozygous mutations), and one mutation was found in two patients (14.3%). In six cases of Mondini dysplasia, two mutations were detected in all of patients (100%). No mutation could be found in the seven cases of other inner ear abnormalities not accompanied with LVAS. No pathogenic mutation was detected in all of these 27 probands in GJB2 gene and mt12SrRNA 1555/1494T. CONCLUSION We have shown that LVAS and Mondini dysplasia closely correlate with SLC26A4 gene. No mutation was detected in seven probands of inner ear malformations not accompanied with LVAS. We should study the molecular pathogenesis of this disease in depth.
Adolescent ; Adult ; Child ; Child, Preschool ; Connexins ; Ear, Inner ; abnormalities ; Exons ; Female ; Genome ; Humans ; Infant ; Male ; Membrane Transport Proteins ; genetics ; Mutation ; Sulfate Transporters ; Syndrome ; Vestibular Aqueduct ; abnormalities ; Young Adult

Many congenital dysplasias of the osseous labyrinth have been identified, and the differential diagnosis of these dysplasias is essential for delivering proper patient management. We retrospectively reviewed the computed tomography (CT) and magnetic resonance (MR) imaging findings of 20 children who had congenital sensorineural hearing loss. The children included cases of enlarged vestibular aqueduct and endolymphatic sac (n=8), aplasia of the semicircular canal (n=4), lateral semicircular canal-vestibule dysplasia (n=3), common cavity malformations with a large vestibule (n=1), cochlear hypoplasia (n=1), Mondini's dysplasia with large vestibular aqueduct (n=1), Mondini's dysplasia with a large vestibule (n=1), and small internal auditory canal (n=1). Six cases were unilateral. Nine cases had combined deformities, and nine cases had cochlear implants. CT was performed with a 1.0-mm thickness in the direct coronal and axial sections with using bone algorithms. MR was performed with a temporal 3D T2 FSE 10-mm scan and with routine brain images. We describe here the imaging features for the anomalies of the inner ear in patients suffering from congenital sensorineural hearing loss.
Brain ; Child ; Cochlear Implants ; Congenital Abnormalities ; Diagnosis, Differential ; Ear, Inner* ; Endolymphatic Sac ; Hearing Loss, Sensorineural* ; Humans ; Magnetic Resonance Imaging* ; Retrospective Studies ; Semicircular Canals ; Vestibular Aqueduct

BACKGROUNDLarge vestibular aqueduct syndrome (LVAS) is a major cause of hearing loss in childhood. This study aimed at measuring external aperture of enlargement of the vestibular aqueduct (EVA) and analyzing relationship between the size of external aperture and hearing loss.

METHODSDiagnostic criteria of LVAS were based on hearing loss and CT images. CT images of temporal bone of 100 LVAS patients were collected and 60 control subjects were reviewed retrospectively in the past 10 years. A battery of audiometric and vestibular function tests were performed. The width of the vestibular aqueduct (VA) was measured on axial CT images of the temporal bone.

RESULTSOne hundred patients (65 men, 35 women) were diagnosed as having the isolated EVA. Hearing loss mostly occurred in early childhood. The diagnosis age of LVAS was 7.7 years on average. The causes of hearing loss could not be confirmed by initial consult. Typically, audiometric curve is the high-frequency down-sloping configuration. 92% of the cases had severe or profound sonsorineural hearing loss (SNHL). The mean size of the external aperture was (7.5 +/- 1.2) mm in present LVAS. Statistical analysis showed that the degree of hearing loss is unrelated to the width of VA.

CONCLUSIONSLVAS is a distinct clinical entity characterized by fluctuating, progressive SNHL. The degree of hearing loss is unrelated to the size of external aperture of VA. The protective management and hearing aid have become the main therapies. The cochlear implantation might be performed if the hearing loss affected learning at school.

Adolescent ; Adult ; Child ; Child, Preschool ; Diagnostic Errors ; Female ; Hearing Loss, Sensorineural ; etiology ; Humans ; Infant ; Male ; Retrospective Studies ; Syndrome ; Tomography, X-Ray Computed ; Vestibular Aqueduct ; abnormalities ; pathology

OBJECTIVETo analyze mutations of SLC26A4 gene and explore their origins for a patient with enlarge vestibuar aqueduct syndrome.

METHODSClinical data and peripheral venous blood samples were collected from the patient and her parents. Genome DNA was extracted from the peripheral blood. All of the 21 exons of the SLC26A4 gene were amplified with PCR and subjected to directly sequencing.

RESULTSThe patient was found to have carried two mutant alleles of the SLC26A4 gene, namely c.1522A to G and c.1229C to T, which were inherited from her father and mother, respectively.

CONCLUSIONSLC26A4 c.1522A to G is likely to be a pathogenic mutation. Above results may facilitate genetic counseling and prenatal diagnosis for this family.

Adult ; Amino Acid Sequence ; Child ; Exons ; Female ; Hearing Loss, Sensorineural ; genetics ; Humans ; Male ; Membrane Transport Proteins ; genetics ; Molecular Sequence Data ; Pedigree ; Vestibular Aqueduct ; abnormalities