The Relationship between the CT Phenotypes of the Inner Ear and Pathogenic Mutations of SLC26A4 in Patients with Sensorineural Hearing Loss / 听力学及言语疾病杂志

ABSTRACT

Objective To explore the relationship between the CT phenotypes of the inner ear and pathogenic mutations of SLC26A4,and analyze the feasibility of using the method of gene sequence analysis to help CT examination in diagnosing part of patients related to vestibular aqueduct malformation with sensorineural hearing loss.Methods A retrospective review of CT findings relating to 2 705 cases of outpatients was carried out.The inner ear malformations diagnosed by CT were classified according to the methods proposed by Sennaroglu 2010.The DNA sequence of SLC26A4 was analyzed in those patients to explore the relationship between the CT phenotypes and the pathogenic mutations of SLC26A4.Results A total of 826 cases of the inner ear malformations were found in 2 705 cases of patients with sensorineural hearing loss by CT examination.The 446 cases of cochlear malformation consisted of the follow types:5 cases of Michel deformity,12 cases of cochlear aplasia,6 cases of common cavity deformity,34 cases of cochlear hypoplasia (CH-Ⅰ type was 9 cases,CH-Ⅱ type was 8 cases and CH-Ⅲ type was 17 cases),389 cases of cochlear incomplete partition (22 cases of IP-Ⅰ type,352 cases of IP-Ⅱ type,15 cases of IP-Ⅲ type).The 380 cases of non-cochlea malformation consisted of the follow types:340 cases of large vestibular aqueduct,40 cases of simple vestibular/semicircular canal/internal auditory canal malformation,and 1 879 normal cases.The DNA sequence results revealed that 517 cases carried pathogenic mutations (B i-allelic mutations) of SLC26A4,among which 164 cases were homozygous and 353 cases were compound heterozygous.Pathogenic mutations of SLC26A4 detected 100 ％ (517/517) in the group related to vestibular aqueduct malformation and the positive rate was 74.71 ％ (517/692).Conclusion The results suggested that pathogenic mutations of SLC26A4 were closely related to the CT phenotypes of vestibular aqueduct malformation.An analysis of SLC26A4 can help CT examination to diagnose part of patients related to vestibular aqueduct malformation with sensorineural hearing loss.