Children who are profoundly deaf fail to develop speech without intervention. Early identification and management of hearing loss before 6 months of age leads to better language development. Causes of deafness can be prenatal, perinatal, or postnatal. Evaluation involves ruling out causes and assessing hearing through objective tests like ABR. Management includes hearing aids, cochlear implants, speech therapy, and special education. Early intervention is important for optimal outcomes.

1. Deaf Child
Dr (Prof) J S Yadav (MS)
Prof & Head
Dept. Of ENT
MLBMC Jhansi

2. • Children with profound (>90 dB loss) or total
deafness fail to develop speech and have often
been termed deaf-mute or deaf and dumb.
• They have never heard speech and therefore do
not develop it
• Whose hearing loss was observed and managed
before 6 months of age had higher scores of
vocabulary, expressive and language skills than
managed after 6 months

4. Causes
• causes before birth (prenatal), during birth
(perinatal) or thereafter (postnatal).
A. PRENATAL CAUSES
1. INFANT FACTORS
• (a) Scheibe dysplasia-most common, Dysplasia is seen
in the cochlea and saccule; hence also called
cochleosaccular dysplasia
• (b)Alexander dysplasia. It affects only the basal turn
of membranous cochlea. Thus only high frequencies are
affected.
• (c) Bing-Siebenmann dysplasia. There is complete
absence of membranous labyrinth.

5. • (d) Michel aplasia. There is complete absence of
bony and membranous labyrinth. No hearing aids
or cochlear implantation can be used.
• (e) Mondini dysplasia. Only basal coil is present
or cochlea is 1.5 turns. deformity may be seen in
Pendred, Waardenburg, branchio-oto-renal,
Treacher-Collins and Wildervanck syndromes
• (f) Enlarged vestibular aqueduct. Vestibular
aqueduct is enlarged (>2 mm), endolymphatic sac
is also enlarged and can be seen on T 2 MRI.

6. 2.MATERNALFACTORS
(a) Infections during pregnancy-toxoplasmosis,
rubella, cytomegaloviruses, herpes type 1 and
2 and syphilis.(TORCHES).
(b) Drugs during pregnancy-Streptomycin,
gentamicin, tobramycin, amikacin, quinine or
chloroquine
(c) Radiation to mother in the first trimester.
(d) Other factors- Nutritional deficiency,
diabetes, toxaemia and thyroid deficiency.

7. B. PERINATAL CAUSES
1. ANOXIA
2. PREMATURITY AND Low BIRTH WEIGHT
3. BIRTH INJURIES
4. Neonatal Jaundice.
5. Neonatal Meningitis
6. Sepsis
7. Time Spent in Neonatal ICU
8. Ototoxic Drugs.

8. C. POSTNATAL CAUSES
1. Genetic- manifests later in childhood or adult
life e.g. Alport, Klippel-Feil, Hurler, etc.
2. Nongenetic- (a) Viral infections (measles,
mumps, varicella, influenza), meningitis and
encephalitis.
(b) Secretory otitis media.
(c) Ototoxic drugs.
(d) Trauma, e.g. fractures of temporal bone,
middle ear surgery or perilymph leak.
(e) Noise-induced deafness.

9. EVALUATION OF A DEAF CHILD
FINDING THE CAUSE
• 1. Suspicion of hearing loss- (i) the child sleeps
through loud noises unperturbed or fails to
startle to loud sounds
(ii) fails to develop speech at 1–2 years

10. METHODS OF HEARING ASSESSMENT
IN INFANTS AND CHILDREN
Neonatal screening procedures
• ABR/OAEs
•Arousal test
• Auditory response cradle
Behaviour observation audiometry
• Moro’s reflex
• Cochleopalpebral reflex
• Cessation reflex
Distraction techniques (6–18 months)
Conditioning techniques (7 months – 2 years)
• Visual reinforcement audiometry
• Play audiometry (2–5 years)
Objective tests
• ABR
• Otoacoustic emissions
• Impedance audiometry

11. ASSESSMENT OF HEARING IN INFANTS AND CHILDREN
• Screening Procedures-
(a) OAEs are generated at outer hair cells and can be picked up
from the external ear as the energy produced by them
travels in reverse direction from outer hair cells → ossicles
→ tympanic membrane → ear canal where it is picked up.
-normal even when VIIIth nerve is
nonfunctional.

12. • (b) ABRs are generated in response to sound
stimulus presented to the ear and picked up
from the scalp. With a response of 30–35 dB
nHL, the infant who passes the test and the
hearing is considered normal

13. (c)Arousal test. A high-frequency narrow band noise is
presented for 2s to the infant when he is in light
sleep. A normal hearing infant can be aroused twice
when three such stimuli are presented to him.
(d)Auditory response cradle is a screening device for
newborns, where baby is placed in a cradle and his
behaviour (trunk and limb movement, head jerk and
respiration) in response to auditory stimulation are
monitored by transducers.

14. 2. Behaviour Observation Audiometry. Auditory
signal presented to an infant produces a
change in behaviour, e.g. alerting, cessation
of an activity, widening of eyes or facial
grimacing.
Moro’s reflex is one of them and consists of
sudden movement of limbs and extension of
head in response to sound of 80–90 dB.

15. Cochleopalpebral reflex the child responds by a
blink to a loud sound.
Cessation reflex an infant stops activity or starts
crying in response to a sound of 90 dB.
3. Distraction Techniques
• Used in children 6–7 months old. The child at
this age turns his head to locate the source of
sound.

16. 4. Conditioning techniques
• (a) Visual reinforcement audiometry (VRA). It is a
conditioning technique in which child is trained to look for an
auditory stimulus by turning his head. This behaviour is
reinforced by a flashing light or an animated toy.
This test helps to determine the hearing threshold &
well-suited between the developmental age of 6 months to 2
years

17. • (b) Play audiometry. The child is conditioned to
perform an act such as placing a marble in a box,
putting a ring on a post or putting a plastic block in a
bucket each time he hears a sound signal
Used in children with developmental age of 2–4
or 5 years.
• (c) Speech audiometry. The child is asked to repeat
the names of certain objects or to point them out on
the pictures

18. 5. Objective tests
(a) Evoked response audiometry.
• (i) Electrocochleography -measure auditory sensitivity
to within 20 dB. But it is an invasive procedure
requiring placement of electrodes through the
tympanic membrane
• ii) Auditory brainstem response. It is not a direct test of
hearing but correlates highly with the puretone
thresholds, It is an objective test and can be done
under sedation as it has no effect on ABR
Screening test, a response to a click stimulus of less than
40 dB nHL or less is the criterion of passing the test.
Hearing threshold- ABR tracing is obtained first at higher
sound stimulus and then gradually lowered till wave V
is just identifiable but repeatable.

19. • (b) Otoacoustic emissions- Transient evoked
emissions (TEOAEs) are absent in ears where
hearing loss exceeds 30 dB. Distortion product
emissions (DPOAEs) are absent when hearing
loss exceeds 50 dB.
• OAEs and ABR have been used both in
screening programmes and in hearing
evaluation in infants and children.

20. • (c) Impedance audiometry. Normally,
stapedius muscle contracts reflexly in
response to a sound of 70–100 dB HL and this
reflex can be recorded, Absence of acoustic
reflex indicates middle ear disorder,
retrocochlear hearing loss or severe to
profound SNHL.

21. MANAGEMENT
• It is essential to know the degree and type of
hearing loss, and other associated handicaps
such as blindness or mental retardation and
whether hearing loss is prelingual (before
development of speech) or postlingual.

22. 1. Parental Guidance – should be dealt with
sympathetically, so as to accept the child.
• care and periodic replacement of hearing aid, change
of ear-moulds as child grows, follow-up visits for re-
evaluation, education at home.
2. 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 as early as possible. If necessary,
binaural aids, one for each ear, can be used. Hearing
aids help to develop lip-reading also.

23. • 3. Cochlear implants - A cochlear implant is an
electronic device that can provide useful
hearing and improved communication abilities
for persons who have severe to profound
sensorineural hearing loss and who cannot
benefit from hearing aids.

24. • 4. Development of Speech and Language.

25. 5. Education of the Deaf
• Radio hearing aids have revolutionized
education of the deaf. In this device, the
microphone and transmitter are worn by the
teacher and the receiver and amplifier by the
child
• With this system, the child can hear the
teacher’s voice better, without being
disturbed by environmental noises.

26. Rehabilitation of the Hearing Impaired
• All hearing-impaired individuals need some sort of aural
rehabilitation for communication. The various means
1. Instrumental devices
(a) Hearing aids
(i) Conventional hearing aids
(ii) Bone-anchored hearing aids
(iii) Implantable hearing aids (vibrant soundbridge)
(b) Implants
(i) Cochlear implants
(ii) Auditory brainstem implants
(c) Assistive devices for the deaf
2. Training
(a) Speech (lip) reading
(b) Auditory training
(c) Speech conservation

27. I. INSTRUMENTAL DEVICES
A. HEARING AIDS
Conventional Hearing Aids-
• It consists of three parts:
• (i) a microphone-which picks up sounds and
converts them into electrical impulses
• (ii) an amplifier, which magnifies electrical
impulses
• (iii) a receiver, which converts electrical impulses
back to sound. This amplified sound is then
carried through the earmould to the tympanic
membrane

28. • Types of Hearing Aids
Air Conduction Hearing Aid - In this, the
amplified sound is transmitted via the ear
canal to the tympanic membrane.
Bone Conduction Hearing Aid - Instead of a
receiver, it has a bone vibrator which snugly
fits on the mastoid and directly stimulates the
cochlea

29. Most of the aids are air conduction type. They
can be:
1. Body-worn types.
2. Behind-the-ear (BTE) types.
3. Spectacle types.
4. In-the-ear (ITE) types.
5. Canal types (ITC and CIC).

30. Various types of hearing aids. (A) Body-worn. (B) Behind-the-ear type. (C) Spectacle type.
(D) In-the-ear type.

31. • CROS (Contralateral Routing of Signals)-
Microphone is fitted on the side of the deaf
ear and the receiver placed in the better ear.
• Now bone-anchored hearing aids are being
preferred for single-sided deafness and have
replaced the use of CROS aids.

32. DISADVANTAGES OF CONVENTIONAL HEARING
AIDS
• Cosmetically unacceptable due to visibility.
• Acoustic feedback.
• Spectral distortion.
• Occlusion of external auditory canal.
• Collection of wax in the canal and blockage of
insert.
• Sensitivity of canal skin to earmoulds.
• Problem to use in discharging ears.

33. • Bone-anchored Hearing Aid (BAHA)-type of
hearing aid which is based on the principle of
bone conduction.
• BAHA has three components:
(i) titanium fixture
(ii) titanium abutment
(iii) sound processor

34. Bone-anchored hearing aid (BAHA).

35. • The titanium fixture is surgically embedded in
the skull bone with abutment exposed outside
the skin. The titanium fixture bonds with the
surrounding tissue in a process called
osseointegration (3months for adults,
6months for children) The sound processor is
attached to the abutment once
osseointegration is complete which usually
takes 2–6 months after implantation.

36. Appearances when sound processor is attached to abutment.

37. • INDICATIONS FOR BAHA
1. When air-conduction (AC) hearing aid cannot be used:
• Canal atresia, congenital or acquired, not amenable
to treatment.
• Chronic ear discharge, not amenable to treatment.
• Excessive feedback and discomfort from air-
conduction hearing aid.
2. Conductive or mixed hearing loss, e.g. otosclerosis and
tympanosclerosis where surgery is contraindicated.
3. Single-sided hearing loss.

38. Implantable Hearing Aids
1. Piezoelectric devices-Examples of such devices
are Envoy, middle-ear transducer (MET or also
called otologic device), Rion and totally
integrated cochlear amplifier (TICA).
• 2. Electromagnetic hearing devices- An example
of such a device is the vibrant soundbridge device
(previously known as the Symphonix device; now
being manufactured by MED-EL).

39. Vibrant Soundbridge Device-

40. Vibrant Soundbridge Device- It is a semi-
implantable device made of two components:
The internal component is called vibrating ossicular
prosthesis (VORP) and is made up of three parts:
the receiver, floating mass transducer (FMT) and
a conductor link between the two. FMT is
connected to the incus
The external component is called the audio
processor which is worn behind the ear

41. • Components of the vibrating ossicular prosthesis
(VORP)

42. B. IMPLANTS
Cochlear Implants
• It works by producing meaningful electrical
stimulation of the auditory nerve where
degeneration of the hair cells in the cochlea
has progressed to a point such that
amplification provided by hearing aids is no
longer effective

43. MED-EL cochlear implants. (A) MED-EL C-401.
(B) Sonata model with ear level speech processor

44. Nucleus cochlear implant (Cochlear Corporation) with ear level
speech processor.

45. Advanced bionics cochlear implant system.

46. A cochlear implant has an external and internal
component.
• 1. External component. It consists of an external
speech processor and a transmitter. The speech
processor may be body worn or behind the ear
type; the latter being preferred.
• 2. Internal component. It is surgically implanted
and comprises the receiver/stimulator package
with an electrode array.

47. • The processor uses a variety of coding
strategies to deliver meaningful speech
parameters from the acoustic stimulus to the
nerve.
• Examples of such strategies are simultaneous
analogue strategy (SAS), continuous
interleaved sampling(CIS), spectral
peak(SPEAK) and advanced combination
encoder (ACE).

49. Principle of cochlear implant.

50. • Imaging of the temporal bone, cochlea, auditory nerve
and brain is carried out using CT and MRI
• Audiological evaluation may include some or all of the
following depending on the age of the patient:
• Pure tone audiogram
• Speech discrimination tests
• Tympanometry
• Otoacoustic emissions (OAE)
• Auditory brainstem responses (ABR)
• Auditory steady state responses (ASSR)

51. • The principle of cochlear implant surgery is to place the
electrode array within the scala tympani of the cochlea
(i) The facial recess approach where a simple cortical
mastoidectomy is done
• Cochleostomy is then performed anteroinferior to the
round window membrane to a diameter of 1.0–1.6 mm
depending on the electrode to be used.
(ii) The pericanal techniques where a tympanomeatal flap
is elevated to perform a cochleostomy either by
endaural or postaural approach. In the pericanal
techniques a bony tunnel is drilled along the external
canal towards the middle ear. The examples of
pericanal techniques include the Veria and
suprameatal recess approach.

52. • Activation of the implant is done 3–4 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 and get the best performance as
the patient gets used to hearing with the
implant

53. COMPLICATIONS OF COCHLEAR
IMPLANT SURGERY
Early complications
• Facial paralysis
• Wound infection
• Wound dehiscence
• Flap necrosis
• Electrode migration
• Device failure
• CSF leak
• Meningitis
• Postoperative dizziness/
vertigo
Late complications
• Exposure of device and
extrusion
• Pain at the site of implant
• Migration/displacement of
device
• Late device failure
• Otitis media

54. Auditory Brainstem Implant (ABI)
• This implant is designed to stimulate the cochlear
nuclear complex in the brainstem directly by
placing the implant in the lateral recess of the
fourth ventricle.
• Such an implant is needed when CN VIII has been
severed in surgery of vestibular schwannoma.
• In these cases, cochlear implants are obviously of
no use.

55. C. ASSISTIVE DEVICES
1. Assistive Listening Devices and Systems(hard-
wired system, induction loops, AM (amplitude
modulation),FM (frequency modulation) or
infrared signals)
2. Alerting Devices
3. Telecommunication Devices

56. II. TRAINING
A. SPEECH READING- Earlier called lip-reading, it is an
integrated process to understand speech by studying
movements of lips, facial expression, gestures and the
probable context of conversation
B. AUDITORY TRAINING - The patient is exposed to
various listening situations with different degrees of
difficulty and taught selectively to concentrate on
speech sounds
C. SPEECH CONSERVATION - aims to educate such a
person to use his tactile and proprioceptive feedback
systems to monitor his speech production.

57. THANK YOU