A narrow internal auditory canal (IAC) with duplication is a rare anomaly of the temporal bone. It is associated with congenital sensorineural hearing loss. Aplasia or hypoplasia of the vestibulocochlear nerve may cause the hearing loss. We present an unusual case of an isolated narrow IAC with duplication that was detected by a CT scan. In this case, the IAC was divided by a bony septum into an empty stenotic inferoposterior portion and a large anterosuperior portion containing the facial nerve that was clearly delineated on MRI.
Child ; Ear, Inner/*abnormalities/radiography ; Female ; Hearing Loss, Sensorineural/*congenital ; Humans ; Tomography, X-Ray Computed

Asp66his, Asp54Lys, and Asp50Asn are mutations in connexin 26 that are observed in the clinic and give rise to autosomal dominant syndromes. They are the result of point mutations in the human gap junction beta-2 gene. In order to investigate the structural mechanism of Bart-Pumphrey Syndrome, Keratitis-Ichthyosis-Deafness Syndrome, and Vohwinkel Syndrome, homology modeling was carried out. Asp66 has direct contact with Asn62 by two hydrogen bonds in the wild-type protein, and in Asp66His, the biggest change observed is a tremendous energy increase caused by hydrogen bond breakage to Asn62. Shifts in the side chain and new hydrogen bond formation are observed for Lys54 compared to the wild-type protein (Asn54) and result in closer contact to Val84. Asp50Asn causes a significant decrease in bond energy, and residual charge reversal repels the ion and metabolites and, hence, inhibits their transportation. Such perturbations are likely to be a factor contributing to abnormal functioning of ion channels, resulting cell death and disease.
Abnormalities, Multiple ; Cell Death ; Computer Simulation ; Connexins ; Fees and Charges ; Gap Junctions ; Hand Deformities, Congenital ; Hearing Loss ; Hearing Loss, Sensorineural ; Humans ; Hydrogen ; Ion Channels ; Keratoderma, Palmoplantar ; Point Mutation ; Transportation

Townes-Brocks syndrome (TBS) is an autosomal dominant disorder with multiple malformations which include dysplastic ears, hearing loss, preaxial polydactyly and/or triphalangeal thumbs, imperforate anus, renal anomalies, congenital heart defects, and mental retardation. However, hypothyroidism is not a common feature of TBS. There have been only three reported cases of TBS associated with hypothyroidism. We report the first case of TBS associated with hypothyroidism in Korea.
Abnormalities, Multiple ; Anus, Imperforate ; Ear ; Hearing Loss ; Hearing Loss, Sensorineural ; Heart Defects, Congenital ; Humans ; Hypothyroidism ; Infant, Newborn ; Intellectual Disability ; Polydactyly ; Thumb

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 ;

Chromosome 11q13 deletion syndrome has been previously reported as either otodental syndrome or oculo-oto-dental syndrome. The otodental syndrome is characterized by dental abnormalities and high-frequency sensorineural hearing loss, and by ocular coloboma in some cases. The underlying genetic defect causing otodental syndrome is a hemizygous microdeletion involving the FGF3 gene on chromosome 11q13.3. Recently, a new form of severe deafness, microtia (small ear) and small teeth, without the appearance of eye abnormalities, was also reported. In this report, we describe a 1-year-old girl presenting with ptosis of the left upper eyelid, right auricular deformity, high-arched palate, delayed dentition, simian line on the right hand, microcephaly, and developmental delay. In this patient, we identified a deletion in the chromosome 11q13.2-q13.3 (2.75 Mb) region by using an array-comparative genomic hybridization analysis. The deletion in chromosome 11q13 results in a syndrome characterized by variable clinical manifestations. Some of these manifestations involve craniofacial dysmorphology and require a functional workup for hearing, ophthalmic examinations, and long-term dental care.
Coloboma ; Congenital Abnormalities ; Congenital Microtia ; Deafness ; Dental Care ; Dentition ; Eye Abnormalities ; Eyelids ; Female ; Hand ; Hearing ; Hearing Loss ; Hearing Loss, Sensorineural ; Humans ; Microcephaly ; Nucleic Acid Hybridization ; Palate ; Tooth ; Tooth Abnormalities

Hearing loss in newborns is the most frequently occurring birth defect. If hearing impaired children are not identified and managed early, it is difficult for many of them to acquire the fundamental language, social and cognitive skills that provide the foundation for later schooling and success in society. All newborns, both high and low risk, should be screened for hearing loss in the birth hospital prior discharge (Universal Newborn Heaing Screening, UNHS). Objective physiologic measures must be used to detect newborns and very young infants with hearing loss. Recent technological developments have produced screening methods and both evoked otoacoustic emission (EOAE) and auditory brainstem response (ABR) have been successfully implemented for UNHS. Audiologic evaluation should be carried out before 3 months of age and infants with confirmed hearing loss should receive intervention before 6 months of age. All infants who pass newborn hearing screening but who have risk indicators for other auditory disorders and/or speech and language delay receive ongoing audiologic surveillance and monitoring for communication development. Infants with sensorineural hearing loss are managed with hearing aids and receive auditory and speech-language rehabilitation therapies. Cochlear implants can be an outstanding option for certain children aged 12 months and older with severe to profound hearing loss who show limited benefit from conventional amplifications.
Child ; Cochlear Implants ; Congenital Abnormalities ; Evoked Potentials, Auditory, Brain Stem ; Hearing Aids ; Hearing Loss ; Hearing Loss, Sensorineural ; Hearing* ; Humans ; Infant ; Infant, Newborn* ; Language Development Disorders ; Mass Screening* ; Parturition ; Rehabilitation

OBJECTIVE: To investigate the phenotype and genetic characters of a Chinese family with an autosomal-dominant inherited high-frequency sensorineural hearing loss. METHOD: A Chinese pedigree associated with an autosomal-dominant inherited high-frequency sensorineural hearing loss was investigated. After obtaining informed consent from all study participants medical and audiological examination to rule out any syndromic hearing impairment. Application of microsatellite markers on DFNA 21 loci preliminary screening of 23 genes, data were analyzed by linkage analysis. RESULT: Proband of the family had been diagnosed with high-frequency sensorineural hearing loss. A Chinese family SX-H043 with non-syndromic hearing loss were ascertained. This Chinese family with late onset hearing impairment spanned four generations and comprised 43 members. The mode of inheritance of the families should be autosomal dominant according to the pedigree. Hearing impairment of affected members in family SX-H043 occurred 25 to 50 years descending audiograms. Whole frequencies became involved with increasing age. CONCLUSION A Chinese family with late-onset high-frequency sensorineural hearing loss were clinically studied. Positive sites were not found in the known deafness loci screening. The information should facilitate future gene scan and linkage analyses for novel relative genes contributing to high-frequency sensorineural hearing loss.
Adult ; Age Factors ; Female ; Genetic Linkage ; Hearing Loss, Sensorineural ; congenital ; genetics ; physiopathology ; Hearing Tests ; Humans ; Inheritance Patterns ; Male ; Microsatellite Repeats ; Middle Aged ; Pedigree ; Phenotype

PURPOSE: We report a case of congenital rubella syndrome with bilateral zonular cataracts. CASE SUMMARY: A 69-year-old man visited the hospital with visual disturbance in both eyes. His mother had been diagnosed with rubella during pregnancy, exhibiting typical fever and rashes. His visual acuity and hearing ability had been poor since birth. Corrected visual acuity was 0.3 in the right eye and 0.4 in the left eye. Slit lamp examination revealed bilateral zonular cataracts. On pure tone audiometry test, pure tone hearing threshold was 73 dB in the right ear and 72 dB in the left ear, corresponding to severe hearing loss in both ears. Echocardiogram showed a 1.5 cm-sized ostium secundum atrial septal defect, causing atrial fibrillation. Laboratory workup revealed an extremely high level of IgG antibody (titer = 1:301), and negative IgM antibody. A rubella IgG avidity test was 95.5%, suggesting remote rubella infection. Chromosomal analysis from peripheral blood did not show any abnormalities. The patient was diagnosed with congenital rubella syndrome with bilateral zonular cataracts. Two months after cataract surgery on both eyes, visual acuity steadily improved to 1.0 in both eyes. CONCLUSIONS: Congenital rubella syndrome is comprised of physical abnormalities such as sensorineural hearing loss, eye defects including congenital cataract, and cardiovascular defects due to gestational rubella infection. The possibility of congenital rubella syndrome should be considered even in old age, and a systemic multi-organ approach is necessary for therapeutic planning.
Atrial Fibrillation ; Audiometry ; Cataract ; Ear ; Exanthema ; Eye ; Fever ; Hearing ; Hearing Loss ; Hearing Loss, Sensorineural ; Heart Septal Defects, Atrial ; Humans ; Immunoglobulin G ; Immunoglobulin M ; Mothers ; Parturition ; Pregnancy ; Rubella ; Rubella Syndrome, Congenital ; Visual Acuity

Kallmann syndrome (KS) is characterized by the association of hypogonadotropic hypogonadism and anosmia. Although the vast majority of KS cases are sporadic, some X-linked recessive (KAL1), autosomal dominant (FGFR1), and autosomal recessive (most commonly GNRHR) modes of inheritance have been described. Two boys were referred to our department because of cryptorchidism and the absence of puberty. Upon laboratory evaluation they were diagnosed with hypogonadotropic hypogonadism. Agenesis of the olfactory bulbs was detected in radiologic tests, and total deletion of the KAL1 gene was detected through multiplex ligation-dependent probe amplification (MLPA). Although cryptorchidism was diagnosed in the siblings, only the older brother suffered from sensorineural hearing loss and right renal agenesis, a feature that had been reported in X-linked KS. We describe herein the clinical heterogeneity of two affected brothers who carry a complete deletion in KAL1; this is the first case of familial Kallmann syndrome due to the complete deletion of the KAL1 gene reported in Korea.
Congenital Abnormalities ; Cryptorchidism ; Hearing Loss, Sensorineural ; Humans ; Hypogonadism ; Kallmann Syndrome ; Kidney ; Kidney Diseases ; Korea ; Male ; Multiplex Polymerase Chain Reaction ; Olfaction Disorders ; Olfactory Bulb ; Population Characteristics ; Puberty ; Siblings ; Wills

Kallmann syndrome (KS) is characterized by the association of hypogonadotropic hypogonadism and anosmia. Although the vast majority of KS cases are sporadic, some X-linked recessive (KAL1), autosomal dominant (FGFR1), and autosomal recessive (most commonly GNRHR) modes of inheritance have been described. Two boys were referred to our department because of cryptorchidism and the absence of puberty. Upon laboratory evaluation they were diagnosed with hypogonadotropic hypogonadism. Agenesis of the olfactory bulbs was detected in radiologic tests, and total deletion of the KAL1 gene was detected through multiplex ligation-dependent probe amplification (MLPA). Although cryptorchidism was diagnosed in the siblings, only the older brother suffered from sensorineural hearing loss and right renal agenesis, a feature that had been reported in X-linked KS. We describe herein the clinical heterogeneity of two affected brothers who carry a complete deletion in KAL1; this is the first case of familial Kallmann syndrome due to the complete deletion of the KAL1 gene reported in Korea.
Congenital Abnormalities ; Cryptorchidism ; Hearing Loss, Sensorineural ; Humans ; Hypogonadism ; Kallmann Syndrome ; Kidney ; Kidney Diseases ; Korea ; Male ; Multiplex Polymerase Chain Reaction ; Olfaction Disorders ; Olfactory Bulb ; Population Characteristics ; Puberty ; Siblings ; Wills