Middle Ear Implant
How does a middle ear implant work?
Rather than simply amplifying sound like a hearing aid, a middle ear implant converts sound into mechanical vibrations that directly stimulate your middle ear.
The middle ear implant consists of two main components, just like the cochlear implant: the surgical implant, which is placed underneath the skin, and the externally worn audio processor. It is held over the implant by a magnet and can be discreetly worn under hair.
How a middle ear implant works:
- The audio processor converts sound waves to electrical signals.
- The signals are then transmitted through your skin to the implant.
- The implant then transmits the signals to a tiny part called a transducer.
- The transducer converts the signals into mechanical vibrations that stimulate movement of your middle ear structures – three little bones known as the ossicles.
- The vibrations transmit the acoustic information to your inner ear and then to your brain, where it is interpreted as sound.
Can you get middle ear implants on the NHS?
There are no NICE guidelines for middle ear implants, athough it is possible to get them through the NHS if you are found to be medically suitable
Who is a middle ear implant suitable for?
A middle ear implant is suitable for people with moderate to severe sensorineural hearing loss, conductive hearing loss or mixed hearing loss who can’t wear hearing aids for medical reasons. These may include outer ear abnormalities, recurrent infections, skin irritations or problems caused by the ear mould blocking the ear canal.
This may be the case if you find your hearing aids just make noise louder rather than making speech clearer.
A full hearing and medical assessment will be made to determine whether you are likely to derive sufficient benefit from a middle ear implant.
You must be five years of age or older and have a functioning auditory nerve. There is no upper age limit.
Benefits of a middle ear implant
Improved hearing quality and speech understanding, particularly in noisy surroundings. Users often describe sound as ‘natural’. Reduced or no feedback - This is because the microphone of the audio processor is farther away from the pinna than a hearing aid microphone. You won’t get a whistling noise. No plugging or blockage of the ear canal - This is an advantage for people who are prone to ear infections.
What to look for in a mddle ear implant?
- Feel and appearance: Audio processors vary in size, weight and some have interchangeable covers in different colours and designs, allowing you to make a bold statement or to wear it discreetly.
- Transcutaneous or percutaneous: Transcutaneous implants transmit sound signals through the intact skin to the implant. There are hardly any skin problems and they have a clear aesthetic advantage when the audio processor is not worn. In percutaneous devices, the audio processor is attached to the skull bone via an abutment to a titanium screw in the non-intact skin. The skin around the screw must be cleaned thoroughly every day to avoid infections, which can occur with percutaneous devices.
- Speech tracking: This helps identify the direction from which speech is coming, sharpening sound.
- MRI compatibility: It’s important to know whether your device is compatible with MRI scanners used for diagnostic medical tests, and to what degree.
- Adaptive directional microphones: These help identify and filter out background noise.
- Wireless connectivity: Your audio processor can connect to your mobile phone, mp3 player or assistive listening device.
- Suitability for children: Not all middle ear implants are suitable for children as some attach to the skull bones, which are still growing. However, others are independent of skull growth as they attach only to middle ear structures (e.g. to the ossicles).
- Intelligent sound adaptation: The audio processor can distinguish between different hearing environments and adjust automatically so you don’t have to keep making manual switches when you go from a quiet area to a noisy one, for example when entering a restaurant.
- Individual programs: For specific environments such as background noise, TV or music.
- Remote control: You can quickly and easily make manual adjustments, if necessary, without removing the audio processor.
Things to consider
Hearing implant surgery is generally considered very safe but any type of surgery carries some degree of risk. This can range from risk due to anaesthetic to post-operative infections.
However, it’s a relatively quick and simple surgery, lasting approximately 60 minutes. Ask your surgeon to explain how the risks and benefits apply to you.