Cochlear implants: Causes, effects and mitigation strategies for the foreign body response and inflammation

Area of Science:

• Biomedical Engineering
• Neuroscience
• Otolaryngology

Background:

• Cochlear implants are vital for severe to profound sensorineural hearing loss.
• Advances allow more patients, including those with residual low-frequency hearing, to benefit.
• Inflammation and fibrosis commonly occur after cochlear implant surgery.

Purpose of the Study:

• To review the current understanding of the foreign body response (FBR) to cochlear implants.
• To examine the impact of FBR on clinical outcomes and future prosthetic development.
• To discuss therapeutic strategies for mitigating the FBR.

Main Methods:

• Review of findings from human subjects and animal models.
• Analysis of factors influencing FBR, including electrode design, surgical techniques, materials, and electrical stimulation.
• Evaluation of current and future mitigation strategies.

Main Results:

• The inflammatory/foreign body response (FBR) is a common consequence of cochlear implantation.
• Factors such as electrode design, surgical trauma, and biomaterials influence the FBR.
• Pharmacological interventions and modifications to surgical techniques can mitigate the FBR.

Conclusions:

• Understanding the FBR is key to improving current cochlear implant efficacy.
• Mitigating the FBR can enhance residual hearing and implant function.
• This knowledge is essential for developing next-generation neural prostheses.