The document discusses approaches to deafness and rehabilitation. It defines types of hearing loss and describes various causes of sensorineural hearing loss including hereditary, infectious, inflammatory, vascular, metabolic, traumatic, degenerative and neoplastic factors. It also discusses the impact of hearing loss and methods of assessing and managing hearing loss, including hearing aids, cochlear implants, and rehabilitation programs. Early identification and intervention are emphasized for minimizing impacts on development.

1. Approch to Deaf and Mute Child
and its rehabilitation
Dr. Sunita Meena
Otorhinolaryngology
PIMS

2. WHODEFINATIONS
• HARD OFHEARING- hearing loss ranging from mild to severe
(>20 dBto 90dB)
• DEAF- profound hearing loss(>90dB)
• DISABLINGHEARINGLOSS- Hearing loss >40 db in the better
hearing earin adults& >30 db in the better hearing ear in
children.

4. causes

5.  Basic pathological cause are
• Hereditary
• Infection
• Inflammations
• Vascular
• Metabolic
• Traumatic
• Degenerative
• Neoplastic

6.  Hereditary
-Down syndrome
-Usher syndrome
-Waardenburg syndrome
 Infection
-Cytomegalovirus (CMV)
-Rubella
-Syphilis
-Meningitis
-Otitis media
-Fungal

7.  Vascular
-Ischaemic heart disease
-Macrovascular disorder : A-V Malformations , aberrant vessels
-Strokes
-Hypertesnsion
-Vasculitis
- Coagulopathies: Hereditary coagulation disorders, sickle cell anemia , blood
viscosity
 Inflammation
-Autoimmune hearing loss: Rheumatoid arthritis, Cogan’s syndrome, SLE,
Takayasu’s disease, IgA Neuropathy ,Behcet’s syndrome ,polyarteritis nodusa
- Demyelination
 Neoplastic
-Diabetes mellitus
-Thyroid dysfunction

8.  Metabolic
-Hyperlipoproteinaemia
-Renal failure
-Hyperuricaemia
-Others
 Trauma and toxicity
-Head injury
-Barotrauma
-Radiotherapy
-Ototoxicity
-Acoustic trauma
 Degenerative
Age related hearing Impairment (Presbyacusis)

9.  Miscellaneous
-Meniere’s syndrome
-Bell’s palsy
-Sarcoidosis
-obscure auditory function
 Sudden
 Causes of sensorineural hearing loss
There are two types of causes
-Prenatal or Perinatal causes
-Postnatal causes

11. PRENATAL OR PERINATAL CAUSES
 Infections such as rubella, herpes, toxoplasmosis, syphilis and cytomegalovirus.
 Hearing loss that runs in family.
 Asphyxia or lack of oxygen at birth.
 Birth weight of less than 1500 grams.
 Defects of head and neck.
POSTNATAL CAUSES
 Exposure to loud noise.
 Bacterial Meningitis
 Ototoxicity caused by exposure to drugs
 Physical damage to head or ear
 Hearing loss due to aging which is called as presbycusis

12. Other descriptors associated with hearing loss
Bilateral
 Hearing loss in both ears.
Unilateral
 Hearing loss in one ear and normal in other ear.
Symmetrical
 In symmetrical hearing loss the degree and configuration are similar in both ears.
Asymmetrical
 In asymmetrical hearing loss the degree and configuration are different in both ears.
Progressive versus sudden
 In progressive hearing loss the loss becomes worse over time where as in sudden the
loss happens quickly.
Fluctuating versus stable
 Fluctuating hearing loss changes over time, sometimes getting better sometimes
getting worse. Stable hearing loss does not change over time and remains the same

13.  Hearing loss can be describe in terms of when it occurs in the process of
development of speech.
- Pre-lingual
- Post-lingual
 Pre-lingual HL : Occurs where the hearing is lost before a child has completely
develop speech and language.
 It may be congenital or acquired in first few year of life.
 All congenital HL Is pre-lingual ,but not all pre-lingual HL is not congenital.
 HL that that occurs at this stage can have a far-reaching impact on verbal and
social skill development.
 Cause:
 Most pre-lingual hearing impairment is due to an acquired condition , usally either
disease or trauma.
 Congenital HL can be caused by genetic or non-genetic factor .

14.  Non genetic factors are
-Maternal infection such as rubella ,HSV, cytomegalovirus
-Lack of oxygen
-Maternal diabetes
-Toxemia during pregnancy
-Low birth weight
-Prematurity
-Birth injuries
-Toxin Including drugs
-Alcohol consumed by mother during pregnancy
-Complication associated with the Rh factor

15.  Genetic factor account for over half of the infants with congenital hearing loss.
 Most of these are caused by an autosomal recessive HL.
 Recent research have found 12 genes which are responsible for congenital
hearing loss.
 Chromosomal disorder associated with sensorineural hearing loss include Down’s
syndrome (trisomy 21) ,trisomy 18, trisomy 13 and deletion of long arm of
chromosome 18. The hearing impairment with these disorders is predominantly
from childhood.

16.  Post-lingual HL :It is more common and means the HL is acquired after speech
and language have develop (usually considered to be after 6 year of age.)
 The hearing loss can still affect communication and educational development.
 Adolescents who develop hearing impairment may experience social isolation,
difficulty in communicating with and being accepted by peers , and reduced
educational achievement.
 A progressive deterioration of hearing is a natural part of aging process.
 Typically hearing loss is gradual , and often detected by family and friends of the
people so affected long before the patients themselves.
 Cause:
 In some cases, the loss is extremely sudden and can be traced to specific
diseases, such as Meningitis, or ototoxic medications.

17.  Ototoxic medication are
-Penicillin
-Oestrogens
-Phosphodiesterase-5 inhibitors
-Pegylated interferon
-Ribavirin
-Aminoglycosides
-Chemotherapeutic agents
 Long term hearing loss is usually the product of chronic exposure to environmental
noise in industrialized countries.
 Certain genetic conditions can also lead to post-lingual deafness which are
autosomal dominant.

18. Degree of hearing loss
Degree of hearing loss refers to severity of hearing loss.
According to Clark J.G. (1981) the degree of hearing loss is
classified as
 Normal- -10 to 15 dBHL
 Slight – 16 to 25 dBHL
 Mild- 26 to 40 dBHL
 Moderate- 41 to 55 dbHL
 Moderately severe- 56 to 70 dBHL
 Severe- 71 to 90 dBHL
 Profound- 91+ dBHL

19. Impact of sensorineural hearing loss(SNHL)
 Functional Impact:
 One of the main impacts of hearing loss is on the individual ability to communicate
with others
 Spoken language development is often delayed in children with unaddressed
hearing loss.
 Unaddressed hearing loss and ear diseases such as otitis media can have a
significantly adverse effect on the academic performance of children.
 Social and emotional impact:
 Exclusion from communication can have a significant impact on everyday life,
causing feeling of loneliness , isolation , and frustration, particularly among older
people with HL.
 Economic impact:
 WHO estimates that unaddressed hearing loss poses an annual global cost of 750
billion international dollars.

20.  In developing countries, children with hearing loss and deafness rarely receive any
schooling.
 Adult with hearing loss also have much higher unemployment rate.

21. Management of Hearing loss
 Assessment of hearing in Infants and children:
• Audiological evaluation:
-Behavioral observation audiometry
-Impedance audiometry
-Brain Stem evoked potential audiometry(BSEP)
-Auditory steady state response audiometry(ASSR)
-Oto-acoustic emission (OAE)
-Speech audiometry
• Radiological evaluation:
-CT Scan
-PET scan
-MRI

22. • Pathological evaluation: it can be
-Cochlear SNHL
-Retrocochlear SNHL
 It cab differentiated by:
-Tone decay test
-Speech Audiometry (pure tone)
-Short increment sensitivity index(SISI)
-Electrocochleography
-Acoustic reflex/Stapedial reflex
-Auditory steady state response(ASSR)
-Brainstem evoked response audiometry

23. • Genetic evaluation:
- Comprehensive prenatal ,neonatal , postnatal history
-Audiometric assessment
-Three generation family history with patient history for family member with
hearing loss , sudden cardiac death, developmental delay, birth defects, common
ancestors b/w parents.
-Physical examination with particular attention to ear structure and other craniofacial
anomalies , dysmorphic features , delayed developmental milestones.
-Genetic testing: It is best carried out in setting both patient/parents are provided
pre-test & post-test genetic counselling . It can not identified 100% genetic hearing
loss.

24.  Other methods assessment of hearing loss:
 Neonatal screening procedures
-ABR/OFAs
-Arousal test
-Auditory response cradle
 Behavior observational audiomatry
-Moro,s reflex
-Cessation reflex
 Destraction techniques (6-18 months)
 Conditioning techniques (7months -2 years)
-Visual reinforcement audiometry
-Play audiometry(2-5 years)

25.  Objective tests
-Evoked response audiometry
. Electrocochleography
. Auditory brainstem response
-Otoacoustic emissions
-Impedance audiometry

26. Management of Hearing loss
 Early detection and intervention are crucial to minimizing the impact of hearing loss
on child’s development and educational achievement.
 In infants and young children with hearing loss, early identification and
management through infants hearing screening programs can improve the
linguistic and educational outcomes of child.
 Children with hearing loss can benefit from:
-Rehabilitation of the Hearing impaired
-Hearing Aids
-Cochlear Implants
-Other assistive devices
-Training of child

27. Management model of audiological rehabilitation
 There are four components:
- Evaluation
- Integration
- Decision making
- Short term remedial process
- On-going rehabilitation
Disability and handicap
Communication status
Associated variables

28. Integration Categorization Goal
setting
Related conditions
Instrumentation
-Personal
-General
Strategy

29. Ancillary help
Communication training

30. Hearing aids
 Most deaf children have a small but useful portion of residual hearing which can be
exploited by amplification of sound.
 Hearing aids should be prescribed by as early as possible. It help to develop lip
reading also.
 It can be
- Directional microphone
- Body-warm device
- Spectacle aids
- In-the-ear hearing aids
- Bone conduction hearing aids

31. Cochlear implant
 Surgically implanted electronic device that can help provide a sense of sound to a
person who is profoundly deaf, or severely hard of hearing.
 The cochlear implant is often referred to as bionic ear.
 Unlike other kinds of hearing aids the cochlear implants dose not amplify sound,
but works by directly stimulating any functioning auditory nerves inside the cochlea
with electrical impulses.
 What is a Cochlear Implant?
 The cochlear implant (CI) is a prosthetic replacement for the inner ear (cochlea) and is
only appropriate for people who receive minimal or no benefit from a conventional
hearing aid.
 The cochlear implant bypasses damaged parts of the inner ear and electronically
stimulates the nerve of hearing.
 Part of the device is surgically implanted in the skull behind the ear and tiny wires
are inserted into the cochlea.

32. Cochlear Implant History
 Pre-1960’s
- beginning studies of electrical stimulation on humans.
 1960’s
- active research of electrical stimulation in human ears.
 1970’s
- first wearable implants designed for long-term stimulation.
 1980’s
- commercial development of the cochlear implant device began.
 1985
- United States Food & Drug Administration (FDA) granted the first approval for
implantation in adults.
 1990
- FDA granted approval for cochlear implants in children.
 Today
- cochlear implantation is a safe and effective medical procedure for
individuals who are severely to profoundly deaf with minimal benefits from
conventional hearing aids.

33. Who is a Candidate?
 Candidates for implants are adults or children (12months or above ) with all of the
following:
 Profound or severe hearing loss in both ears (this includes people with so-called
"nerve" deafness).
 Hearing aids but receive little or no benefit from them in understanding speech by
listening alone.
 Best results are obtained from those patients who good hearing at least until the
age of 6 years.
 A hearing aids trial and evaluation is mandatory in determining the candidacy for
cochlear implant.
 Speech and language evaluation is required to assess the child’s communicative
status and to determine any developmental language or articulation disorders.
 Psychological evaluation is performed where there may be concerns regarding the
cognitive status or mental function of patient.

34. Indications for Cochlear Implantation
 Criteria for Children :
-12 months or older.
-Bilateral severe-to-profound sensorineural hearing loss.
-No appreciable benefit with hearing aids after 3-6 months trial.
-Enrolled in aural/oral education program.
-No medical or anatomic contraindications.
-Motivated parents.

35.  Criteria for Adult:
 In adult , post-lingual sensarinural hearing loss are best candidate for cochlear
implant.
-18 years old and older (no limitation by age).
-Bilateral severe-to-profound sensorineural hearing loss (60 dB hearing loss or
greater with little or no benefit from hearing aids after 6 months trial)
-Psychologically suitable.
-No anatomic contraindications.
-Medically not contraindicated.

36. Components of cochlear implant

37. Components

38.  There are four basic component of cochlear implant:
-A microphone, which picks up sound from the environment.
-A speech processor, which selects and arranges sounds picked up by the
microphone.
-A transmitter and receiver/ stimulator, which receive signals from the speech
processor and convert them into electric impulses.
-And electrodes, which collect the impulses from the stimulator and send them to
the brain.

39. How Does a Cochlear Implant Work?
 Sound is received by an microphone that rests over the ear like a behind-the-ear
hearing aid.
 Sound is sent from the microphone to the signal processor by a thin cable.
 Signal processor translates the sound into electrical codes.
 Codes are sent by a thin cable to the transmitter held to the scalp by its attraction
to a magnet implanted beneath the skin.
 Transmitter sends codes across the skin to a receiver/stimulator implanted in the
mastoid bone.
 Receiver/stimulator converts the codes to electrical signals.
 Electrical signals are sent to the specified electrodes in the array within the
cochlea to stimulate neurons.
 Neurons send messages along the auditory nerve to the central auditory system in
the brain where they are interpreted as sound.

40. Surgical Procedure
 Most common surgical procedure for Cochlear Implant is called Mastoidectomy
with Facial Recess Approach (MFRA). Other methods include VARIA techniques,
Trans canal approach, etc.
 Overview of surgical steps:
-Skin Incision(end-aural)
-Drill Implant Bed, Electrode Channel, Suture Holes, And Mastoidectomy
-Posterior tympanotomy.
-Cochleostomy: A 1mm opening is made in front of round window into the bottom
term of cochlea .
-Inserting The Electrode Array.
-Fixation Of The Implant.
-Intraoperative mapping(NRT) is done to check electrode and its response.
-Post-op X-ray View.

41. Activation of the Device:
 It is done at4 to 6 weeks after surgery.
 The programming of the external speech processor is a procedure that must be
repeated one week later and then periodically thereafter.
 Risks of CI Surgery:
-Injury to the facial nerve
-Post operative dizziness
-Meningitis
-Leakage of CSF
-Delayed device failure (less than 2%)
-Device migration or extrusion (rare)

42.  Subject factors that might affect the performance of the Cochlear Implant:
-Etiology
-Age and Onset of Deafness
-Age at Implantation
-Residual Hearing
-Functioning auditory nerve
-For adults: Good speech, language, and communication skills
-Good motivation
-Support from family and friends

43. Postoperative Mapping (programming)of Implant & Habilitation:
 Activation of implant is done 4-6 weeks after implantation. Following this the
implant is programmed or mapped.
 Mapping is done on a regular basis during postoperative rehabilitation to fine-tune
the processor get the best performance as the patient gets used to hearing with
implant.
 Mapping is be done by-
1 -NRT (Neural Response threshold)
-At the time of surgery
-At the time of switch on
-Postoperative as per standardized schedule
2-BOA(Behavioral Observation Audiometry)
-At the time of switch on
-Postoperative as per standardized schedule

44. 3-eESRT (electrically Evoked Auditory Stapedius Response Threshold)
- At the time of surgery
4-eEABR(electrically Evoked Auditory Brainstem Response)
5-eEACP(electrically Evoked Compound Action Potential)

45. Other Assistive Devices
 Assistive Listening Devices and Systems
 Alerting Devices
 Telecommunicating Devices

46. Training of child
 Speech Reading
 Auditory Training
 Speech Conservation