Cochlear Implants: An Excursus into the Technologies and Clinical Applications

Abstract

Hearing loss causes severe alterations in social function and daily communications. Cochlear device implantation (CDI) is the only beneficiary method for auditory rehabilitation in patients with severe to profound sensorineural hearing loss (SNHL). Regarding a report in 2014, over 300,000 people had received cochlear implants throughout the world since December 2012 among which about 60,000 were adults and 40,000 were children in the United States. In this chapter, we discuss the history, origin, mechanism of action, and type of cochlear implants, as well as method of surgery and complications.

Neurosensory Prosthetics: An Integral Neuromodulation Part of Bioelectronic Device

“…They stimulate auditory nerve fibers through electrodes implanted in the cochlea and are beneficial in patients with sensorineural hearing loss but with functional auditory nerve fibers ( Svirsky, 2017 ). CIs may be totally implantable or may have external components (external microphone, processor, and transmitting coil) for empowering electrodes ( Khosravi et al, 2018 ). In totally implantable CIs, the entire system is located underneath the skin.…”

“…CIs may be implanted in a single ear (unilateral implantation) or in both ears (bilateral implantation). Compared with those patients who underwent unilateral cochlear implantation, patients with bilateral CIs have better auditory perception and can effectively localize the source of sound ( Eapen et al, 2009 ; Xue et al, 2009 ; Khosravi et al, 2018 ). However, the cost of implants, along with complications associated with the implantation, outweighs the benefits of bilateral implantation ( Xue et al, 2009 ).…”

“…However, the cost of implants, along with complications associated with the implantation, outweighs the benefits of bilateral implantation ( Xue et al, 2009 ). The surgical procedure for placement of CI is safe, although there are chances of post-implant complications, which may be categorized as minor or major complications ( Venail et al, 2008 ; Farinetti et al, 2014 ; Khosravi et al, 2018 ). Major complications include death, meningitis, surgery without reimplantation in cases (scalp necrosis, severe infection, electrode shifting, eardrum perforation, receiver repositioning, and cholesteatoma), tinnitus, facial stimulation, and pain that cannot not be alleviated by electrode deactivation ( Venail et al, 2008 ).…”