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Objectives/hypothesis: To characterize the severity and natural history of hearing loss, and the prevalence of having a cochlear implant in a maturing cohort of individuals with enlarged vestibular aqueduct (EVA) and zero or one mutant allele of SLC26A4.Study Design: Prospective cohort study of subjects ascertained between 1998 and 2015 at the National Institutes of Health Clinical Center.Methods: Study subjects were 127 individuals (median age, 8 years; range, 0-59 years) with EVA in at least one ear.Results: Ears with EVA and zero or one mutant allele of SLC26A4 had mean 0.5/1/2/4-kHz pure-tone averages of 62.6 and 52.9 dB HL, respectively, in contrast to EVA ears with two mutant alleles of SLC26A4 (88.1 dB HL; P < .01). This association was independent of age, sex, or side of EVA (P < .001). Natural history of hearing loss was not associated with number of mutant alleles (P = .94). The prevalence of having a cochlear implant was nine (12%) of 76, two (13%) of 15, and 12 (38%) of 32 subjects with zero, one, and two mutant alleles, respectively (P = .00833). This association was not independent (P = .534) but reflected underlying correlations with age at time of first audiogram (P = .003) or severity of hearing loss (P = .000).Conclusions: Ears with EVA and zero or one mutant allele of SLC26A4 have less severe hearing loss, no difference in prevalence of fluctuation, and a lower prevalence of cochlear implantation in comparison to ears with two mutant alleles of SLC26A4.Level Of Evidence: NA Laryngoscope, 127:E238-E243, 2017. [ABSTRACT FROM AUTHOR]

Objectives/hypothesis: Hearing loss and enlarged vestibular aqueduct (EVA) can be inherited as an autosomal recessive trait caused by mutant alleles of the SLC26A4 gene. In some other families, EVA does not segregate in a typical autosomal recessive pattern. The goal of this study was to characterize the SLC26A4 genotypes and phenotypes of extended families with atypical segregation of EVA.Study Design: Prospective study of cohort of families ascertained between 1998 and 2014 at the National Institutes of Health Clinical Center.Methods: Study subjects were members of eight families segregating EVA in at least two members who were not related as siblings. Evaluations included pure-tone audiometry, temporal bone imaging, SLC26A4 nucleotide sequence analysis, SLC26A4-linked marker genotype and haplotype analysis, and pedigree analysis.Results: One family had members with EVA caused by different etiologies, and two families had pseudodominant inheritance of recessive mutations of SLC26A4. In five families, the etiology remained unknown and could include inheritance of mutant alleles at another genetic locus, nongenetic influences, or a combination of these factors.Conclusions: Familial EVA can demonstrate a variety of atypical segregation patterns. Pseudodominant inheritance of SLC26A4 mutations or recessive alleles of other hearing loss genes may be more likely to occur in families in which deaf individuals have intermarried. The etiologic basis of atypical segregation of EVA without detectable SLC26A4 mutations remains unknown. Future studies of these families may reveal novel genes for EVA.Level Of Evidence: NA Laryngoscope, 126:E240-E247, 2016. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis: Identify correlations among SLC26A4 genotype, cochlear structural anomalies, and hearing loss associated with enlargement of the vestibular aqueduct (EVA). Study Design: Prospective cohort survey, National Institutes of Health, Clinical Center, a federal biomedical research facility. Methods: Eighty-three individuals, 11 months to 59 years of age, with EVA in at least one ear were studied. Correlations among pure-tone hearing thresholds, number of mutant SLC26A4 alleles, and the presence of cochlear anomalies detected by computed tomography or magnetic resonance imaging were examined. Results: Linear mixed-effects model indicated significantly poorer hearing in ears with EVA in individuals with two mutant alleles of SLC26A4 than in those with EVA and a single mutant allele ( P = .012) or no mutant alleles ( P = .007) in this gene. There was no detectable relationship between degree of hearing loss and the presence of structural cochlear anomalies. Conclusions: The number of mutant alleles of SLC26A4, but not the presence of cochlear anomalies, has a significant association with severity of hearing loss in ears with EVA. This information will be useful for prognostic counseling of patients and families with EVA. Laryngoscope, 2010 [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to characterize the temporal bone phenotype associated with a mutation of GJB2 (encoding connexin 26).Study Design: The authors conducted correlative clinical, molecular genetic, and postmortem histopathologic analysis.Methods: The study subject was a male infant with keratitis-ichthyosis-deafness (KID) syndrome. We performed a nucleotide sequence analysis of GJB2 and a histopathologic analysis of the temporal bones.Results: The subject was heterozygous for G45E, a previously reported KID syndrome mutation of GJB2. The primary inner ear abnormality was dysplasia of the cochlear and saccular neuroepithelium.Conclusions: GJB2 mutations can cause deafness in KID syndrome, and possibly in other GJB2 mutant phenotypes, by disrupting cochlear differentiation. [ABSTRACT FROM AUTHOR]

Objective Evaluation of the auditory manifestations of Keratitis-Ichthyosis-Deafness (KID) syndrome, a rare genodermatosis characterized by follicular hyperkeratosis, vascularizing keratitis, and congenital hearing loss. Study Design Five individuals with sporadic KID syndrome were evaluated in the outpatient audiology clinic at the Warren Grant Magnuson Clinical Center of the National Institutes of Health. Methods Audiologic examinations included pure-tone audiometry, speech audiometry, and middle ear immittance testing. Auditory brainstem responses and otoacoustic emissions were analyzed in 2 subjects. Results Four subjects had prelingual, bilateral, profound sensorineural hearing loss, whereas the fifth subject had significant residual hearing that exhibited no progression on serial audiograms. All 5 subjects had a history of non-erosive keratosis obturans and cutaneous cysts in the external ear canals that prevented continuous use of ear molds. Conclusions The sensorineural hearing loss in KID syndrome is generally prelingual and profound. This combination of auditory and cutaneous phenotypes is similar to those previously reported for KID syndrome. KID syndrome presents a difficult challenge for communication rehabilitation because keratitis may impair the perception of sign and spoken language, and the cutaneous manifestations routinely curtail use of external amplification devices. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis: To determine the mode of inheritance of familial nonsyndromic Mondini dysplasia. Study Design: Correlative clinical genetic analysis of a single kindred. Methods: Clinical history, physical examination, audiologic analysis, computed tomography of the temporal bones, and cytogenetic analysis. Results: The male proband, three affected sisters, and an affected brother are offspring of unaffected parents. The mother and an unaffected brother have audiologic findings suggestive of heterozygous carrier status for a recessive hearing loss gene. Conclusions: Pedigree analysis indicates autosomal recessive inheritance in this family. The observed inheritance and clinical, audiologic, and radiologic findings are different from those previously described for another family with nonsyndromic Mondini dysplasia.1 The phenotype in this study family therefore represents a distinct subtype, indicating clinical and genetic heterogeneity of this disorder. This information should facilitate future molecular linkage analyses and genetic counselling of patients with inner ear malformations. Key Words: Mondini, sensorineural, hearing loss, familial, inner ear. [ABSTRACT FROM AUTHOR]

The large vestibular aqueduct syndrome (LVAS) is a distinct clinical entity characterized by stepwise progressive sensorineural hearing loss associated with isolated enlargement of the vestibular aqueduct. A correlative clinical, audiologic, vestibular, cytogenetic, and radiographic analysis of a family with inherited LVAS was performed. The male proband and his affected brother are offspring of unaffected parents, and have no other abnormalities. Pedigree analysis suggests autosomal recessive or X-linked inheritance with variable expressivity of LVAS in this family. This study is the first description of familial inheritance of LVAS. LVAS may account for a significant number of patients with nonsyndromal, genetic sensorineural hearing loss. Future molecular analyses of this study family may identify the causative gene(s) in LVAS. [ABSTRACT FROM AUTHOR]