Middle ear implant
What is a middle ear implant?
A middle ear implant is a hearing device that picks up sounds with a sound processor / audio processor that sits on the head and converts the sounds into mechanical stimulation of the ossicles of the middle ear.
A middle ear implant (MEI) makes the structures in the middle ear vibrate in much the same way as normal sounds move the bones in the middle ear by converting sounds into vibrations.
Unlike a hearing aid, a middle ear implant converts sound into vibrations. This mechanical energy is used to directly stimulate the middle ear structures. With a middle ear implant, the ear canal remains completely open.
A middle ear implant consists of an internal and an external part.
External part
The external component of the middle ear implant is the sound processor / audio processor which contains the battery, the microphone and the digital signal processing.
The sound processor / audio processor converts sounds into electrical signals that are transferred to the implant. The sound processor / audio processor is worn on the head and can be discreetly covered by the wearer’s hair. The sound processor / audio processor is held in place over the implant by a magnet in the implanted part.
Internal part
The internal component of a middle ear implant is surgically placed under the skin towards the back of the head. One part of the internal component is the Floating Mass Transducer (also called FMT), which is attached to a vibratory structure in the middle ear. The FMT vibrates specifically to each patient’s hearing needs, causing the structures of the ear to vibrate. These vibrations can be amplified and adjusted to compensate for different types and degrees of hearing loss. The FMT is the central component of a middle ear implant and is smaller than a grain of rice.
How does a middle ear implant work?
A middle ear implant works like this:
- Sounds are picked up by the sound processor / audio processor's microphone.
- The sound processor / audio processor converts environmental sounds into a digital signal.
- The digital signal is transmitted across the skin to the implant.
- The implant sends the signal via the conductor link to the Floating Mass Transducer (FMT) in the middle ear.
- The Floating Mass Transducer (FMT) converts the signal into vibrations that directly drive the middle ear structure.
- The vibrations conduct sound to the inner ear and to the brain.
Who can benefit from middle ear implants?
A middle ear implant can be used as treatment for a sensorineural hearing loss as well as for a conductive hearing loss and a mixed hearing loss.
Among people who can benefit from middle ear implants are:
- People with an obstruction of the outer or middle ear
- People who cannot for some reason wear hearing aids or ear moulds
- People who do not benefit from sound amplification
In other conditions or circumstances, middle ear implants may also be the right solution.
It is important to note that middle ear implants do not restore hearing to normal hearing like the hearing of a person without hearing loss.
Candidate for a middle ear implant?
If you think you may benefit from a middle ear implant you should start by contacting an ENT-doctor or an audiologist.
Other types of implants:
Cochlear implants
Bone conduction devices
Auditory Brainstem Implant (ABI)