[The changes of blood-labyrinth barrier in idiopathic sudden sensorineural hearing loss and the relationship with clinical features and prognosis]

Objective: To investigate the clinical features and prognosis in patients with idiopathic sudden sensorineural hearing loss (ISSNHL) with blood-labyrinth barrier breakdown (BLB-B). Methods: Clinical data of patients with unilateral ISSNHL hospitalized from December 2017 to December 2018 were retrospectively analyzed. According to the results of 3D-FLAIR MRI and enhanced MRI scanning, these patients were divided into two groups, i.e., normal and abnormal inner ear groups. The patients in abnormal inner ear group were further divided into two subgroups: BLB-B and BLB-B with exudation. The differences and correlations among the groups in clinical characteristics, in terms of gender, age, deafness side, basic diseases, dizziness/vertigo, vestibular function, hearing loss degree, as well as classification of hearing curve, and prognosis were analyzed by statistical software SPSS 23.0. Results: Data were collected from 150 cases, in which 68 were male and 82 were female, aged (46.2±14.6) years, including 67 cases with normal inner ears and 83 cases with abnormal inner ears (13 cases with BLB-B; 70 cases with BLB-B and exudation). The dizziness/vertigo incidence, side ratio, hearing loss degree, classification of hearing curve, vestibular dysfunction (vestibular double temperature test, HIT and VAT) and therapeutic effect were different between normal and abnormal inner ear groups (P<0.05). The dizziness/vertigo incidence, side ratio, hearing loss degree, classification of hearing curve, vestibular dysfunction (vestibular double temperature test, o/cVEMP, HIT and VAT) and therapeutic effect were different among normal inner ear, BLB-B and BLB-B with exudation groups (P<0.05). Pairwise comparison between groups revealed that vestibular dysfunction (vestibular double temperature test, o/cVEMP, HIT and VAT) and therapeutic effect were different between normal inner ear and BLB-B groups (P<0.05); The dizziness/vertigo incidence, side ratio, hearing loss degree, classification of hearing curve, vestibular dysfunction (vestibular double temperature test, o/cVEMP, HIT and VAT) and therapeutic effect were different between normal inner ear and BLB-B with exudation groups (P<0.05). There was no significant different between BLB-B and BLB-B with exudation groups. Conclusion: BLB-B displayed by 3D-FLAIR MRI manifestation in ISSNHL patients indicates more serious cochlear and vestibular dysfunction, and worse therapeutic effect.

[A hereditary hearing loss case accompanied by unilateral sudden hearingloss:GJB2 235delC homozygotes related late-onsetmoderate hearing impairment]

Summary A sporadic,case suffering from sudden hearing loss of left ear accompanied by tinnitus when he visited our hospital in 2015,whose hearing threshold had a fluctuation in recent two year.Mutation screening of GJB2 gene,was carried out on the case and his parents by polymerase chain reaction amplification and Sanger sequencing.Targeted 307 genes capture and next-generation sequencing(NGS) was performed to explore,additional possible genetic codes.GJB2 235delC homozygotes were identified,and NGS showed no other pathogenic,likely pathogenic variations or modifier genes.The overexpression of Connexin30 or the presence of modifier genes may be the possible mechanisms of the late-onset moderate hearing impairment phenotype,and much more cases collection and further in vivo/vitro experiments need to be done to decipher the genetic code.