Hearing and Balance Services including Hearing Aids.

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Rehabilitation/Hearing Aids

 

Following a hearing aid assessment, there is a period to discuss means of amplification. This includes hearing aids as well as other assistive listening devices. The type of hearing aid that is suitable depends upon a number of factors:

  • degree of hearing loss
  • size of ear
  • physical limitations of style of aid
  • requirement for certain features

There are 3 basic styles of hearing aid and some of their features are listed below. There are other aspects of each style that may also be available and some of these are also listed. At present, all hearing aids need a battery to power them. These currently range from the smallest number 5 cell becoming progressively larger through the 10; 312; 13; 675 and finally the AA/A penlight batteries. These are fitted progressively to allow for greater power consumption and then size of the hearing aid so that the approximate life of each battery should be between 10 days and 3 weeks.

1: IN THE EAR

This range covers hearing aids where the microphone, amplifier and loudspeaker are enclosed within the boundaries of the ear

Completely in the Canal Hearing Aid - CIC:

  • Placement: just inside the entrance to the external auditory meatus.
  • Battery size: 5 or 10 battery.
  • Controls: self-adjusting (preset volume) or remote controller
Advantage:

reduced wind noise (protected by tragus); reduced feedback with telephone use; discreet.
Aid can have brightly coloured shell since it is not visible in the ear.

Disadvantage: suitable only for mild to moderate hearing losses; requires large, straight ear canal; good dexterity needed; very small batteries.

 

In the Canal Hearing Aid - ITC :

  • Placement: in the entrance to the external auditory meatus.
  • Battery size: 10 or 312 battery
  • Controls: self-adjusting; remote controller or volume wheel


Advantage: small, compact aid; natural placement; discreet. Aid can have brightly coloured shell since it is not visible in the ear.
Disadvantage: suitable only for mild/moderate to severe hearing losses; good dexterity needed; small batteries, small hearing aid.

 

In the Ear Hearing Aid - ITE:

  • Placement: in the bowl of the ear or pinna.
  • Battery size: 312 or 13 battery.
  • Controls: self-adjusting; remote controller; volume wheel; switch for 2nd program or T-coil.

Advantage: natural placement; large enough to accommodate coil for use in loop systems; suitable for most hearing losses except the severe to profound.
Disadvantage: some increased wind noise.

 

2: BEHIND THE EAR - BTE

These perhaps more conventional style hearing aids have been fitted for many years. They can accommodate a wide range of hearing losses but are more commonly fitted where there is a severe to profound loss or certain features are needed, e.g. directional microphones (although these are available in some ITE aids).

  • Placement: behind the ear attached to a clear ear mould.
  • Battery size: 312, 13 or 675 battery.
  • Controls: self-adjusting; remote controller; volume wheel; switch; T-coil/noise suppression.
Advantage: suitable for most hearing losses except the severe to profound; large enough to accommodate coil for use in loop systems; direct input options available such as extension microphone, television adapter. loop; using an open ear mould, will suit patients with chronic middle ear problems where aeration is a necessity.
Disadvantage: increased wind noise; slightly poorer directionality (unless using a specific directional microphone array); some problems with glasses; larger device.

 

3: BODY WORN AIDS

There are many instances where this type of hearing aid is preferred over both the in and behind the ear style of aid. It would most appropriately be fitted to a patient of reduced mobility where only sounds from the front would need to be heard.

  • Placement: clipped to a shirt pocket or in neck pouch and attached via a cord to a clear ear mould.
  • Battery size: AA or AA battery
  • Controls: volume wheel; switch; T-coil/noise suppression
Advantage: very powerful hearing aid; high number of direct inputs to aid from remote microphones and television adapters; good frontal directionality; easily visible controls; excellent battery life.
Disadvantage: clothing noise; cord tangles; larger device.