Molecular and Cellular Mechanisms of Loss of Residual Hearing after Cochlear Implantation

Abstract

Cochlear implantation is followed by an inflammatory response involving several pathways that lead to either short-term or long-term sensory hair cell degeneration. Future studies should focus on revealing the precise molecular mechanisms induced by cochlear implantation to allow the discovery of new targets for the effective prevention and treatment of loss of residual hearing.

Hearing Loss After Activation of Hearing Preservation Cochlear Implants Might Be Related to Afferent Cochlear Innervation Injury

“…Finally, intracochlear pathologies (e.g. fibrosis) that might necessitate higher charge to reach stimulable neural elements of the cochlea cannot be excluded based on these data 18 . Nonetheless, the strength of the association discovered here is sufficient to provide a basis for further study and should be considered by CI audiologists when programming hearing preservation cochlear implantees.…”

Impact of Intrascalar Electrode Location, Electrode Type, and Angular Insertion Depth on Residual Hearing in Cochlear Implant Patients

“…Some variables can be improved upon, such as surgical trauma, implant size, and surgical approach. There are other factors, however, that, at present, cannot be clinically modified for human subjects such as individual inflammatory response and cellular apoptosis (11,15,16).…”

Application of a TNF-alpha-inhibitor into the scala tympany after cochlear electrode insertion trauma in guinea pigs: Preliminary audiologic results

“…Thereby, it is attempted to exploit the characteristics of this agent as an antioxidant precursor that has the potential to interfere with free radical formation after cochlear insertion trauma and subsequent activation of reactive oxygen species pathways (Jia et al, 2013).…”

“…It comprises early onset infl ammation by tissue injury (Jia et al, 2013) and delayed onset proliferation by foreign body reaction and chronic infl ammation (Bas et al, 2012b). Consequential for the outcome of cochlear implantation are apoptosis of auditory nerve fi bers, fi brous scar and bone formation (Jia et al, 2013), as it infl uences electrode impedance as well as electric stimulation and thereby dynamic range and power consumption (Duan et al, 2004).…”