Enlarged vestibular aqueduct(EVA), the most frequent identifiable cause of congenital hearing loss, is evaluated with high-definition multidetector CT in the axial plane. Our purpose was to determine which reformatted...Enlarged vestibular aqueduct(EVA), the most frequent identifiable cause of congenital hearing loss, is evaluated with high-definition multidetector CT in the axial plane. Our purpose was to determine which reformatted CT measurements are most reproducible. Seven multiplanar reformatted images were created for each of the 64 temporal bones in patients with EVA. Intraclass correlation coefficients(ICC) were used to assess inter-observer variability, and both linear regression and ROC analyses were used to compare the measurements with severity of hearing loss, as assessed by pure tone audiometry. All seven measurements had excellent inter-observer variability, with average-measure ICC ranging from 0.92 to 0.98. There was no statistically significant correlation between the radiologic degree of aqueduct enlargement and severity of hearing loss using any of the seven measurements; ROC analyses revealed areas under the curves ranging from 0.57 to 0.73. Optimal accuracy was obtained with a threshold of 1.75 mm as measured at the aqueductal aperture in the P€oschl plane, with sensitivity of 0.75 and specificity of0.63. Although the radiologic measurement may not serve as a reliable tool for assessing severity of EVA, P€oschl plane reformatting has proven to be better than conventional axial acquisition plane for identifying patients with clinically significant hearing loss.展开更多
nPendred syndrome （PS） is characterized by autosomal recessive inheritance of goiter associated with a defect of iodide organification, hearing loss, enlargement of the vestibular aqueduct （EVA）, and mutations of ...nPendred syndrome （PS） is characterized by autosomal recessive inheritance of goiter associated with a defect of iodide organification, hearing loss, enlargement of the vestibular aqueduct （EVA）, and mutations of the SLC26A4 gene. However, not all EVA patients have PS or SLC26A4 mutations. Two mutant alleles of SLC26A4 are detected in 1/4 of North American or European EVA populations, one mutant allele is detected in another 1/4 of patient populations, and no mutations are de-tected in the other 1/2. The presence of two mutant al-leles of SLC26A4 is associated with abnormal iodide or-ganification, increased thyroid gland volume, increased severity of hearing loss, and bilateral EVA. The pres-ence of a single mutant allele of SLC26A4 is associated with normal iodide organification, normal thyroid gland volume, less severe hearing loss and either bilateral or unilateral EVA. When other underlying correlations are accounted for, the presence of a cochlear malformation or the size of EVA does not have an effect on hearing thresholds. This is consistent with observations of an Slc26a4 mutant mouse model of EVA in which hearing loss is independent of endolymphatic hydrops or in-ner ear malformations. Segregation analyses of EVA in families suggest that the patients carrying one mutant allele of SLC26A4 have a second, undetected mutant allele of SLC26A4, and the probability of a sibling hav-ing EVA is consistent with its segregation as an autoso-mal recessive trait. Patients without any mutations are an etiologically heterogeneous group in which siblings have a lower probability of having EVA. SLC26A4 muta-tion testing can provide prognostic information to guide clinical surveillance and management, as well as the probability of EVA affecting a sibling.展开更多
Backgroud Large 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 rela...Backgroud Large 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. Methods Diagnostic 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. Results One 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. Conclusions LVAS 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.展开更多
Enlarged vestibular aqueduct(EVA)is a radiologic malformation of the inner ear most commonly seen in children with sensorineural hearing loss.Most cases of EVA with hearing loss are caused by biallelic mutations of SL...Enlarged vestibular aqueduct(EVA)is a radiologic malformation of the inner ear most commonly seen in children with sensorineural hearing loss.Most cases of EVA with hearing loss are caused by biallelic mutations of SLC26A4.In this review,we discuss the potential mechanisms underlying the pathogenesis of hearing loss with EVA due to malfunction of SLC26A4,the detection rates of SLC26A4 mutations in EVA patients from different populations,and the role of other genetic factors(eg,mutations in FOXI1 and KCNJ10)as etiologic contributors to EVA.Elucidating the molecular etiology of EVA-associated hearing loss may facilitate genetic counseling and lead to potential therapeutic strategies.展开更多
文摘Enlarged vestibular aqueduct(EVA), the most frequent identifiable cause of congenital hearing loss, is evaluated with high-definition multidetector CT in the axial plane. Our purpose was to determine which reformatted CT measurements are most reproducible. Seven multiplanar reformatted images were created for each of the 64 temporal bones in patients with EVA. Intraclass correlation coefficients(ICC) were used to assess inter-observer variability, and both linear regression and ROC analyses were used to compare the measurements with severity of hearing loss, as assessed by pure tone audiometry. All seven measurements had excellent inter-observer variability, with average-measure ICC ranging from 0.92 to 0.98. There was no statistically significant correlation between the radiologic degree of aqueduct enlargement and severity of hearing loss using any of the seven measurements; ROC analyses revealed areas under the curves ranging from 0.57 to 0.73. Optimal accuracy was obtained with a threshold of 1.75 mm as measured at the aqueductal aperture in the P€oschl plane, with sensitivity of 0.75 and specificity of0.63. Although the radiologic measurement may not serve as a reliable tool for assessing severity of EVA, P€oschl plane reformatting has proven to be better than conventional axial acquisition plane for identifying patients with clinically significant hearing loss.
基金Supported by NIH intramural research funds Z01-DC-000039,Z01-DC-000060 and Z01-DC-000064,NIH grants R01-DK43495 and P30-DK34854Kansas State University CVM-SMILE and the Kansas City Area Life Science Institute
文摘nPendred syndrome （PS） is characterized by autosomal recessive inheritance of goiter associated with a defect of iodide organification, hearing loss, enlargement of the vestibular aqueduct （EVA）, and mutations of the SLC26A4 gene. However, not all EVA patients have PS or SLC26A4 mutations. Two mutant alleles of SLC26A4 are detected in 1/4 of North American or European EVA populations, one mutant allele is detected in another 1/4 of patient populations, and no mutations are de-tected in the other 1/2. The presence of two mutant al-leles of SLC26A4 is associated with abnormal iodide or-ganification, increased thyroid gland volume, increased severity of hearing loss, and bilateral EVA. The pres-ence of a single mutant allele of SLC26A4 is associated with normal iodide organification, normal thyroid gland volume, less severe hearing loss and either bilateral or unilateral EVA. When other underlying correlations are accounted for, the presence of a cochlear malformation or the size of EVA does not have an effect on hearing thresholds. This is consistent with observations of an Slc26a4 mutant mouse model of EVA in which hearing loss is independent of endolymphatic hydrops or in-ner ear malformations. Segregation analyses of EVA in families suggest that the patients carrying one mutant allele of SLC26A4 have a second, undetected mutant allele of SLC26A4, and the probability of a sibling hav-ing EVA is consistent with its segregation as an autoso-mal recessive trait. Patients without any mutations are an etiologically heterogeneous group in which siblings have a lower probability of having EVA. SLC26A4 muta-tion testing can provide prognostic information to guide clinical surveillance and management, as well as the probability of EVA affecting a sibling.
文摘Backgroud Large 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. Methods Diagnostic 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. Results One 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. Conclusions LVAS 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.
文摘Enlarged vestibular aqueduct(EVA)is a radiologic malformation of the inner ear most commonly seen in children with sensorineural hearing loss.Most cases of EVA with hearing loss are caused by biallelic mutations of SLC26A4.In this review,we discuss the potential mechanisms underlying the pathogenesis of hearing loss with EVA due to malfunction of SLC26A4,the detection rates of SLC26A4 mutations in EVA patients from different populations,and the role of other genetic factors(eg,mutations in FOXI1 and KCNJ10)as etiologic contributors to EVA.Elucidating the molecular etiology of EVA-associated hearing loss may facilitate genetic counseling and lead to potential therapeutic strategies.
