Both cochlear implants (CI) and middle ear implants (MEI) will require internal surgery to place an implant in the middle or inner ear, and both will work with an external sound processor. These implants will only be considered when the conventional hearing aids do not provide practical benefits to those with hearing loss or some other ear complications or malformation that prevent patients from wearing conventional hearing aids.
For CI, the internal device will be surgically inserted in the cochlea, which is one of the critical parts of the inner ear. On the contrary, the implant of MEI will be placed in the middle ear structure of any of the three tiny bones (malleus, incus, or stapes) or even at the round window (an opening at the cochlea covered by a membrane). This is based on the nature and type of hearing loss.
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For CI, only those with severe to profound sensorineural hearing loss will be viable candidates for cochlear implantation; MEI can be suitable and beneficial for all types of hearing loss including conductive, mixed and sensorineural hearing loss. The severity can go from mild to severe hearing loss.
The candidacy of CI and MEI is different because the MEI will function by creating vibration and moving the middle ear structure, which then creates pressure to move the inner ear fluid and send signals to the brain, which perceives it as sound. MEI creates extra force to amplify the sound which relies on the working cochlea and hearing nerve. However, for CI, the sound will bypass the outer, middle ear and damaged inner hair cells. The electrodes implanted inside the cochlea will directly stimulate the hearing nerve by electrical signals. CI doesn’t need to work on the intact hair cells inside the cochlea to send the signal into the brain.
Both CI and MEI provide sound stimulation through different mechanisms. Thus, for those who don’t benefit from conventional hearing aids and wish to find alternatives to fix the hearing problem, you may contact us to find out more.
Are you considering cochlear implant to hear again? Check with us if this is a good option for you. Book an online consultation here or if you prefer a physical consultation at our centre you can book an appointment here.