Thia presentation is about how to assess hearing loss, how to categorise it, how to investigate it, and finally how to rehabilitate the deaf people of different ages

1. Rehabilitation of Impaired Hearing
DR REHMAN SHER
TMO ENT MMC

2. Rehabilitation Of Hearing Impaired
 All hearing-impaired individuals need some sort of aural rehabilitation for
communication. The various means available to them are:
1. Instrumental devices
a. Hearing aids
b. Implants
c. Assistive devices for the deaf
2. Training
a. Speech (lip) reading
b. Auditory training
c. Speech conservation

3. 1. Instrumental Devices
A. HEARING AIDS: A device which amplify sound reaching the ear
a. Conventional hearing aids
b. Bone anchored hearing aids
c. Implantable hearing aids
1. Conventional Hearing aids: these are air conduction type hearing aids consist of three parts;
 Microphone,
 Amplifier,
 Receiver
2. Bone conduction Type: fit on mastoid bone
 Instead of Receiver it has vibrator which directly stimulate cochlea
 Most of the hearing aids are air conduction type, they can be;

5. Types Of Conventional Hearing Aids
1. Body worn types;
 most common type
 Microphone and amplifier in one case worn at chest level
 Receiver is situated at ear level
 Useful for severely deaf person or children with congenital deafness
2. Behind the ear type;
 All three components are in one unit
 Worn behind the ear
 Useful in slight to moderate hearing loss at highr frequencies

6. Types Of Conventional Hearing Aids
3. In The Ear Type;
 Entire hearing aid is housed in an earmould which can be worn in te ear
 Useful for mild to moderate hearing loss with flat cofiguration
 Very popular beacausenof its cosmetic appeal
4. Spectacle Type;
 Its modification of behind the ear type HA
 HA is fitted in the Frame of the spectacles
 Useful for candidates who use spectacles

7. 5. Canal Type;
 Entire Hearing aid can be worn in ear canal
 For this type of HA ear canal should be large and wide
 Useful in mild to moderate type of hearing loss of high frequencies

8. Indications For Hearing Aid
1. SNHL;
 Which interfer with day to day activity
 HA may not suit all such patients because of intolerabe distortion in some and particularly in
those with recruitement
2. Deaf Child;
 Should be fitted with HA as soon as possible for development of speech and language
 In severely deaf child binaural hearing aid are useful
 Lip reading should be practiced simultaneousely
3. Conductive Deafness;
 When surgery is either refused, not feasable or failed

9. Fitting of Hearing Aid
While fitting a hearing aid,
consideration is given to:
1. Degree of hearing loss.
2. Configuration of hearing loss (type of frequencies affected).
3. Type of hearing loss (conductive or sensorineural).
4. Presence of recruitment.
5. Uncomfortable loudness level.
6. Age and dexterity of patient.

10. Fitting of Hearing Aid
7. Condition of the outer and middle ear.
8. Cosmetic acceptance of the aid.
9. Type of earmould.
10. The type of fitting, whether it is monoaural (one aid
only), binaural (one aid for each ear), binaural with
y-connection (one aid but two receivers, one for each
ear) or the contralateral routing of signals type.

11. Contra lateral routing of signal (CROS)
 In this type of Hearing aid microphone is on side of deaf ear and receiver on
better Ear
 Nowadays it is replaced by bone anchord hearing aids
bone anchord hearing aids;
It has three components
1. Titanium fixture; it is surgically embedded in skull bone
2. Titanium abutment; it is exposed outside on the skin
3. Sound processor; it received sound

12.  Fixture bond with surrounding tissue in a process called osseointegration
 It takes 2-6 months
 The processor is attached to abutment
Candidancy profile;
1. Patient who has chronic inflamation or infection of auditory canal
2. Children with malformed or absent external auditory canal as on microtia or canal
atresia
3. Single sided deafness

13. Surgery;
 Single stage procedure in adults
 Two stage procedure in children
Complications;
 Occaisional failure of osseointegration
 Local infections And inflamation

14. Implantable middle ear hearing aids
 It works on direct drive principle
 It uses mechanical vibrations delivered to ossicular chain
 Available in two types
1. Piezoelectric Devices
 Passes electric current to piezoelectric crystals which changes its volume and thereby
produces a vibrating signal
 Its coupled with ossicles and drive ossicular chain
2. Electromagnetic Hearing aids
 Electric current in coil produces magnetic flux that drives the adjacent magnet
 The small magnet is attached to one of the ossicles to convey vibrations to cochlea

15. CANDIDANCY
 Adults 18 or older
 Moderate to severe sensory neural hearing loss
 Should have experience of using traditional hearing aids
 Candidates who desire for this type of hearing aids are usually complaining of
dissatisfaction of quality of sound of the current hearing aids
 Other reasons are akluj ine aapke naal impacted wax inability to wear the
conventional hearing aids due to sensitive ear canal

16. Advantages
 Eliminate inherent issues of conventional hearing aids such as occlusion, feedback,
discomfort and wax related problems
 One major advantage is the ability to provide improved sound quality particularly in
noisy environment

17. IMPLANTS
Cochlear implants
 These are electronic devices that provide useful hearing and improved communication
abilities for persons who have severe to profound sensory neural hearing loss and who
cannot benefit from hearing aids
 It works on the electrical stimulation of the auditory nerve
 Components of cachlear implants
1. External component
 It has speech processor and transmitter
 Speech processor maybe body worn ir behind the ear type
2. Internal component
 It is surgically implanted and has receiver or stimulator package with an electrode array

18. Candidency profile
1. It can be done in both children and adults
2. Bilateral severe to profound SNHL
3. Little or no benefits from hearing aids
4. No medical contraindications for the surgery
5. Realistic expectations
6. Good family and social support towards rehabilitation

19. Outcome
Outcome of cochclear implants different on several factors
1. Previous auditory experience that is pre-lingual or post-lingual
2. Age
3. Short duration of deafness
4. Neural plasticity without auditory system

20. Auditory brainstem implants (ABI)
 This implant is designed to stimulate the cochlear nucleus complex in the brain
stem directly by placing the implant in the lateral recess of the fourth ventricle
 Such an implant is needed when cranial nerve 8 has been severed in surgery of
vestibular schwannoma

21. Assistive devices
 Different devices are needed for the hearing impaired person to coup with the
special situations
 These device can be divided into three groups
1. assitive listening devices and systems
1. This device is help the hearing impaired person to listen a patiently in the presence of
background nice poor the telephone in auditorium or theatres
2. It include hardware system induction loops, amplitude modulation, frequency
modulation, or infrared signals

22. Allertive Devices
 Hearing impaired person may not here a telephone or a doorbell, a baby crying in
another room an alarm clock or the noise of a smoke detector
 allertive devices are useful in such situations
3. Telecommunication devices
 Telephone amplifier is the best example of this type of assistive devices

23. Training
1. Speech reading
 Called lip reading
 It is a process to understand speech by studying moment of lips facial expression
gestures and the probable context of conversation
2. Auditory training
 It is useful for those using hearing AIDS and cochlear implants
3. Speech conservation
 Speech conservation aims to teach the patient how to control his own voice

24. Thanks