There are so many different styles of hearing instruments available today that it is easy to match one up to your hearing loss and lifestyle. They fall into three main categories:
Let’s look at these individually and see what advantages and disadvantages each style has.
This is the most well-known hearing instrument. It has two parts:
- the earmould - which is a piece of acrylic/silicon customised to the shape of your ear. This sits in your concha (i.e. the bowl of your ear).
- the hearing instrument - which houses all the electronics. It hangs over the back of the ear and has a plastic tube to join it to the earmould.
The advantages are:
- They're usually less expensive than In-The-Ear (ITEs) models.
- You can attach different hearing instruments to the earmould, allowing you to try out new models or use a spare/loan aid whilst your usual one gets repaired.
- It doesn't need as much maintenance as an ITE because the electronics are kept away from the wax, body heat and moisture of the ear canal.
- They can be less conspicuous than an ITE because they can use a clear plastic earmould instead of the flesh-coloured plastic of an ITE. The BTE hearing instrument is usually small enough to be hidden behind the ear.
- There's less chance of annoying feedback (whistling).
- They can be more powerful due to the room they have for larger components.
- There's more room on the instrument for ‘extras’, such as directional microphones to help you in background noise.
- They can be fitted to a pair of spectacles.
- Some people find their larger size easier to handle.
- They're ideal for children who grow so fast that they would require a new In-the-Ear hearing instrument every few months. Instead, with a BTE they just swap the old earmould for a new one.
- If you have a deformed ear or a problem with your ear canals (such as constant discharge or bony growths), some BTEs can bypass the ear canals by sending sound to your inner ear by vibrating your mastoid bone.
The disadvantages of the BTE are:
- Because they need two pieces – the earmould and the instrument itself – they can be more fiddly for people with limited dexterity, for example people with arthritis.
- Some people don't like to admit they have a hearing problem and think that a BTE will draw attention to it, whereas a CIC (completely-in-canal) aid will be hidden inside their ear canal.
- Some people associate a BTE with the flesh-coloured, shiny plastic prosthetic-looking hearing aids supplied by the NHS. They don't realise that the range of BTEs is now so vast that it includes cosmetically coloured instruments (e.g. silver, hair colours such as brown and 'trendy' colours such as green). Even the earmould can customised to be glittery, marbled, coloured or even (for those of you with a strange sense of humour) have a spider suspended in the clear plastic!
With an In-the-Ear hearing instrument (ITE) all the electronics are stored in one piece of custom moulded plastic that sits in the bowl of your ear - no need for a separate earmould.
There are different styles of ITE and it all comes down to how far hidden into the ear they go.Starting with the most visible they are:
- Full Shell – this takes up the entire bowl of the ear (i.e. the concha).
- Half Shell – this takes up half the concha and so is a little more discreet.
- In-the-Canal – only a small proportion, for example the volume control, is visible at the
entrance of the canal. Most of it is located inside the ear canal.
- Completely-In-Canal – almost invisibly. It fits so far down the ear canal that it is removed from the ear by a small nylon cord.
The advantages of an ITE
- Cosmetic – some models are less noticeable than a BTE.
- They use the shape of the ear to catch and enhance sound before it enters the hearing instruments microphone.
- The loudspeaker is closer to the eardrum so it requires less power to amplify the sound.
- If inserted deep enough they can help overcome the problems of 'occlusion'.
- Some people with limited dexterity (e.g. arthritis) find them easier to handle because they just have the one piece to insert.
The disadvantages of an ITE
- Usually more expensive, due to the custom moulding and smaller components.
- Longer production time, again due to the custom moulding.
- Will probably require more maintenance because they're exposed to wax, body heat and moisture in the ear canal.
- More prone to feedback. (Some newer hearing instruments however have built-in feedback cancellers for limiting this problem, but it does depend on how great your hearing loss is).
This type of hearing instrument is not very common nowadays but may be recommended in three situations:
- When the hearing loss is so severe that lots of power is needed.
- When someone has dexterity problems and needs a nice big volume control, easily accessible (i.e. near where their hands are), and need a long-lasting battery so it can be changed by a hearing aid dispenser at regular intervals.
- Very young children (e.g. babies) - body worn hearing aids stay on better!
Next subject: Tell me about Digital Hearing Instruments
