Abstract

ABSTRACTWhile cochlear implantation (CI) technology has greatly improved over the past 40 years, one aspect of CI that continues to pose difficulties is the variability of outcomes due to numerous factors involved in postimplantation performance. The electric acoustic stimulation (EAS) system has expanded indications for CI to include patients with residual hearing, and is currently becoming a standard therapy for these patients. Genetic disorders are known to be the most common cause of congenital/early‐onset sensorineural hearing loss, and are also involved in a considerable proportion of cases of late‐onset hearing loss. There has been a great deal of progress in the identification of deafness genes over the last two decades. Currently, more than 100 genes have been reported to be associated with non‐syndromic hearing loss. Patients possessing a variety of deafness gene mutations have achieved satisfactory auditory performance after CI/EAS, suggesting that identification of the genetic background facilitates prediction of post‐CI/EAS performance. When the intra‐cochlear etiology is associated with a specific genetic background, there is a potential for good CI performance. Thus, it is essential to determine which region of the cochlea is affected by identifying the responsible genes. This review summarizes the genetic background of the patients receiving CI/EAS, and introduces detailed clinical data and CI/EAS outcomes in representative examples. Anat Rec, 303:563–593, 2020. © 2020 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.

Highlights

  • Cochlear implantation (CI) is the surgical insertion of a device to provide electrical stimulation directly to the auditory nerve (Fig. 1)

  • This review summarizes the responsible genes reported in CI patients and discusses what we have learned from the progress of two newly progressing fields of science, CI and the genetic background of patients

  • otoacoustic emission (OAE) have generally disappeared by two years of age; many patients are diagnosed with non-syndromic sensorineural hearing loss (NSHL)

Read more

Summary

Cochlear Implantation and Deafness Genes

Cochlear implantation (CI) is the surgical insertion of a device to provide electrical stimulation directly to the auditory nerve (Fig. 1). CI provides a good outcome for the majority of cases, factors affecting the outcomes of CI vary among patients. One reason of such variations is thought to be. Genetic factors represent the most common etiology in severe-to-profound hearing loss, and might be one of the key determinants of outcomes for CI and electric acoustic stimulation (EAS) (Miyagawa et al, 2016) (Fig. 2). Compared to the prelingual group, many genes with autosomal dominant inheritance, such as MYO7A, ACTG1, DFNA5, MYO6, and CRYM, as well as mitochondrial genes reported to cause progressive hearing loss, were found to be involved

Screening Strategy for Deafness Genes
DFNA DFNB
Molecules Encoded by Deafness Genes
Etiology and CI Outcome
LittlEARs score LittlEARs score
Progress of CI
Spiral Limbus Spiral Ganglion
Importance of Genetic Testing for EAS Patients
Total score
Candidacy for EAS
Nonsense mutation or frame shift mutations
Left Right Bilateral
Before surgery
CONCLUSION
Findings
LITERATURE CITED

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.