otolaryngology , audiology , hearing assessment, ear

1. 1
Hearing Assesment in Children
Presented by : Dr. Khalil Elkahlout
MBBS , R1 resident ENT department
Alshifa medical complex
Supervisor : Dr.Jabr Abu Amro

2. 7
Hearing impairment
WHO definition of hearing impairment :
“Hearing impairment means complete or partial loss of the ability
to hear from one or both ears; this is mild or worse hearing
impairment, 26 dB or greater hearing threshold, averaged at
frequencies 0.5, 1, 2, 4 kHz.”
Disabling hearing impairment means moderate or worse hearing
impairment in the better ear; that is the permanent unaided hearing
threshold level for the better ear of 41 or 31 dB or greater in age
over 14 or under 15 years respectively, averaged at frequencies 0.5, 1,
2, 4 kHz.

3. 8
Prevalence Of Hearing Loss
• 1 to 3 per 1000 infants will have permanent
sensorineural hearing loss
• 10/1000 from the NICU
• Rate increases to 6/1000 by school age
Hearing Assessment in Infants and Children: Recommendations Beyond Neonatal Screening- Pediatrics 2003

4. 6
Why hearing tests are important
• Soon after birth can help identify most babies with significant hearing
loss, and testing later in childhood can pick up any problems that have been
missed or have been slowly getting worse.
• It's important to identify hearing problems as early as possible because they
can affect your child's speech and language development, social skills and
education.
• An early diagnosis will also help ensure you and your child have access to
any special support services you may need.

5. 5

6. 9
Types of Hearing Loss
• Conductive hearing loss is caused by
blockage in the transmission of sound
to the inner ear.
• Ear infections are the most common
cause of this type of hearing loss in
infants and young children.
• This loss is usually mild, temporary, and
treatable with medicine or surgery.

7. 10
Types of Hearing Loss ( Cochlear hearing loss)
• Sensorineural hearing loss can happen
when the sensitive cochlea has
damage or a structural problem
• The most common type, may involve a
specific part of the cochlea such as the
inner hair cells, outer hair cells, or both.

8. 11
Types of Hearing Loss
Mixed hearing loss happens when a
person has both conductive and
sensorineural hearing loss.

9. Permanent childhood hearing impairment
- congenital :denote hearing impairment that is present at, or very soon
after, birth.
- Acquired hearing impairments are considered to be
(i) postnatally acquired PCHI (e.g. as a sequela of meningitis or head
injury);
(ii) progressive hearing impairments usually diagnosed following ongoing
progression of the impairment post diagnosis;
(iii) late-onset

10. 12
Why Is Early Identification Of Hearing Loss Important?
• A critical period exists for optimal language skills to
develop, and earlier intervention produces better
outcomes.
• Treatment of hearing defects has been shown to improve
communication.
• Children with hearing loss typically experience significant
delays in language development and academic
achievement.

11. 1
3
Signs of a hearing loss
• limited, poor, or no
speech
• frequently inattentive
• difficulty learning
• seems to need higher TV
volume
• fails to respond to
conversation level
speech
• Answers inappropriately
• fails to respond to his or
her name or
• easily frustrated when
there's a lot of
background noise

12. 14
High-risk Indicators For Hearing Loss In Children
From Birth To 24 mo of Age
• family history of early childhood deafness
• history of treatment in (NICU) for more than 48 hours
• Ear and craniofacial anomaly (e.g. cleft palate) associated with hearing impairment.
• In utero infection associated with SNHL (eg, toxoplasmosis, rubella, cytomegalovirus,
herpes, syphilis)
• Hyperbilirubinemia at levels requiring exchange transfusion
• Birth weight less than 1500 g
• Bacterial meningitis
• Low Apgar scores: 0–3 at 5 min; 0–6 at 10 min
• Respiratory distress (eg, meconium aspiration)
• Prolonged mechanical ventilation for more than 10 d
• Ototoxic medication (eg, gentamicin) administered for more than 5d or used in combination with
loop diuretics
• Physical features or other stigmata associated with a syndrome known to include SNHL
(eg, Down syndrome, Waardenburg syndrome)

13. 15
Speech-Language-Auditory Milestones
• Birth to 3 mo. :
• Startles to loud noise
• Awakens to sounds
• Blinks or widens eyes in response to noises
• 3 to 6 mo:
• Quiets to mother’s voice
• Stops playing, listens to new sounds
• Looks for source of new sounds not in sight
• 6 to 9 mo:
• Enjoys musical toys
• Coos and gurgles with inflection
• Says ‘mama’
• 12 mo to 15 mo:
• Responds to his or her name and ‘no’
• Follows simple requests
• Uses expressive vocabulary of 3 to 5 words
• Imitates some words

14. 16

15. 17
When to test Hearing ?
• Within a few weeks of birth – newborn hearing
screening and it's often carried out before discharge
from hospital after birth.
• From 9 months to 2.5 years of age – If any
concerns about child's hearing
• At around 4 or 5 years old – Most children will have
a hearing test when they start school

16. 18
Newborn Hearing Screening
• 1999 - The American Academy of Pediatrics
endorses: Universal newborn hearing screening.
• Detection of hearing loss before three months
of age.
• Intervention services initiated by six months of
age.
Language of early- and later-identified children with hearing loss. Yoshinaga Itano C, Pediatrics. 1998

17. Newborn Hearing screening Guidelines
- It is recommended that all infants get screened for hearing loss prior to the age of 1
month according to this protocol.
- Initial screening is performed using Otoacoustic Emission (OAE machine)
- The initial screening should consist of 2 attempts maximum per ear
- If infant does not pass the initial screening, or if results could not be obtained in one or
both ears, infant is scheduled for a rescreening at the same PHC center.
Re-screening
- Rescreening is performed utilizing the same test/tests as in the initial screening (above)
- Rescreening is recommended to be performed before/by 1 month of age.
- If an infant does not pass the rescreening, or if results cannot be obtained in one or both
ears, he/she should be referred for diagnostic audiological evaluation.

18. Screen with OAE
Fail
Pass
Rescreen with
OAE 1x
ABR
Fail
Pass
Fail
Pass
Refer to audiologist for diagnostic
evaluation
Refer to audiologist
for ABR rescreen
Fail
Pass
Risk indicators
No risk indicators
Finished
Monitor
ABR at 6 Months

19. 1
9
Newborn Hearing
Techniques
• Evoked otoacoustic emissions (EOAE).
• Auditory brainstem response (ABR).
• Auditory steady state response (ASSR) test

20. 20
Evoked Oto-Acoustic Emissions (EOAE)
• Oto-acoustic emissions (OAEs) are sounds
originated in the cochlea that can be recorded
by a sensitive microphone fitted in the ear
canal.
• These sounds are created by the movements
of the outer hair in the cochlea as they
respond to auditory stimulation.
• The OAEs can be as loud as 30dB SPL, and are
generated only when the organ of Corti and
the middle ear are in near normal condition.
• OAEs are affected by conductive and sensori-
neural hearing losses.

26. 2
1
Auditory Brainstem Response (ABR) or
Brain stem evoked response audiometry (BERA)
• A test that uses electrodes (wires)
attached with adhesive to the baby's
scalp. While the baby sleeps, clicking
sounds are made through tiny
earphones in the baby's ears.
• The test measures the brain's activity
in response to the sounds.
• As in EOAE, this test is painless and
test time around 30
-
45 min/baby

27. 22
Auditory Brainstem Response (ABR) or
Brain stem evoked response audiometry (BERA)
• ABR measures the electrical
response in the auditory nerve
and brainstem.
Clinical applications
- Acoustic neuroma diagnosis (pre-MRI
time). Latency I–V > 4.2 ± 0.2ms,
and the interaural I–V latency 0.2–0.4ms.
- Threshold determination. Especially in
children (used with Oto-acoustic
emissions in neonatal screening). Can
detect threshold, but not frequency
specific.
- Intra-operative testing. During acoustic
neuroma surgery.
The waveform created in ABR testing has five
waves :
I. Auditory nerve.
II. Cochlear nucleus.
III. Superior olivary complex.
IV. Lateral lemniscus.
V. Inferior colliculus.

28. 23
Auditory steady state response (ASSR) test
• This test is similar to the ABR, though an infant usually needs to be sleeping or
sedated for the ASSR test.
• Sound passes into the ear canals, and a computer picks up the brain's response to t
he sound and automatically decides whether hearing loss is mild, moderate, severe,
or profound.
• This ASSR test has to be done with (and not instead of) ABR to check for hearing.

29. 24
Middle ear muscle reflex (MEMR)
• The MEMR (also called acoustic reflex test) tests how well
the ear responds to loud sounds by evoking a reflex.
• In a healthy ear, this reflex helps protect the ear against loud
sounds.
• For the MEMR, a soft rubber tip is placed in the ear canal.
• A series of loud sounds are sent through the tips into the ears
and a machine records whether the sound has
triggered a reflex.
• Sometimes the test is done while the child is sleeping.

30. 25
Hearing tests for the infant
The use of the above EOAE and ABR tests, PLUS
Behavioral audiometry
• Auditory signal presented to an infant
produces a change in behaviour e.g alerting,
cessation of an activity or widening of eyes.
• Moro`s reflex: sudden movement of limbs and
extension of head in response to sound of 80-
90 dB.
• Cochleo-palpebral reflex: Child responds by a
blink to aloud sound.
• Cessation reflex: Infant stops activity or starts
crying in response to a sound of 90 dB.

31. 26
• To test hearing in children from
approximately 6 months to 2.5 years
old.
• Child is trained to look toward a sound
source. When the child gives a correct
response, the child is "rewarded"
through a visual reinforcement, such as
a toy that moves or a flashing light.
• Once this conditioned response is
reliably observed, the stimuli can be
presented at ever decreasing levels until
auditory threshold or minimum audible
levels have been reached.
Visual reinforcement audiometry

32. 2
7
Hearing tests for the toddler
Play audiometry
(Conditioned Play Audiometry)
For children between 1.5 and 5 years old
Sounds will be played through
headphones or speakers and your child
will be asked to perform a simple task
when they hear the sound. This may
vary from putting a ball in a bucket to
completing a puzzle or touch or move a
toy.
This test relies on the cooperation of the
child, which may not always be given.

33. 2
8
Hearing tests for the toddler
Speech audiometry
• Child is asked to repeat
the names of certain
objects or to point them
out on the pictures.
• Voice can be gradually
lowered.
• In this way hearing level
and speech discrimination
can be tested.

34. 29
Hearing tests for children older than 3 to 4 years
The above mentioned tests, along with the
following:
• Pure tone audiometry ("sweep
test”): used to screen a child's hearing
before they start school
• A machine generates sounds at
different volumes and frequencies.
• The sounds are played through
headphones and your child is asked to
respond when they hear them by
pressing a button.
• By changing the level of the sound, the
tester can work out the quietest
sounds your child can hear.

35. 30
Pure Tone Audiometry
• An audiometer is an electronic device which produces pure tones,
intensity of which can be increased or decreased in 5 dB steps.
• AC thresholds are measured for tones of 125,250,500,1K,2K,4K,8K Hz.
• BC thresholds are measured for tones of 250,500,1K,2K,4K Hz.
• It is charted in the form of a graph called audiogram.
• Handheld audiometers have a sensitivity of 92 percent and a specificity
of 94 percent in detecting sensorineural hearing impairment.

36. 31
Pure Tone Audiometry
Types
1. Screening audiometry - presents tones across the speech spectrum
(500 to 4,000 Hz) at the upper limits of normal hearing (25 to 30 dB for
adults, and 15 to 20 dB for children)
• Results are recorded as pass, indicating that the patient's hearing levels are within
normal limits, or refer, indicating that hearing loss is possible and a repeat screening
test or a threshold search test is recommended
2. Threshold search audiometry - determines the softest sound a patient
can hear at each frequency 50 percent of the time. (Modified Hughson-
Westlake method) - “Up 5-down 10" method of threshold estimation

37. 32
Nomenclature on the pure tone audiogram
O Right air conduction
X Left air conduction
[ Masked right bone
conduction
] Masked left bone
conduction

38. 33
Hearing tests for children older than 3 to 4 years
Immittance audiometry: an objective technique which evaluates
middle ear function by three procedures:
1. Static immittance,
2. Tympanometry, and
3. Acoustic reflex threshold sensitivity.
No single test should be considered a diagnostic 'end-all'. However, when
immittance test results are integrated with audiological data, they provide a
powerful adjunct to assist the physician in making a clinical diagnosis.

39. 34
1. Static Compliance
• Reciprocal of stiffness, is a measure of ear canal volume under two
specific physical conditions.
• In the first condition, (+) 200 mm H2O of positive air pressure is
applied to the ear canal and a volume (C1) is read. The second
volume reading (C2) occurs at a pressure value of maximum
eardrum compliance.
• Normally maximum eardrum compliance occurs when atmospheric
pressure is equal on both sides of the eardrum (0 mm H2O).

40. 35
2. Tympanometry (impedance audiometry)
• It is an important objective test of middle-ear function.
• The sound transmission from the external to the middle ear is optimal when the pressure
• in the ear canal is the same as the middle ear.
• The compliance of the tympanic membrane is measured as a function of mechanically
varied air pressure in the external auditory canal and hence the middle-ear pressure is
indirectly measured.
A soft rubber tube will be placed at the
entrance of the child's ear. Air is gently
blown down the tube and a sound is
played through a small speaker inside it.
The tube then measures the sound that's
bounced back from the ear.

41. Types of Tympanograms
Type A: normal. Peak is at 0mmH2O, range from –
100 to +200.
The peak can be shallow,represent restricted TM
movement (as in otosclerosis or other ossicular
fixation, and tympanosclerosis), or high, representing
hyper-compliance (ossicular disarticulation, flaccid
tympanic membrane).
Type B: flat or very low, rounded peak. Has a 96%
positive predictive value for middle-ear effusion. It
can also represent a TM perforation
Type C: shows low pressure in the middle ear and
represent ETD.
Ear-canal volume is approximately 2ml in adults, in
children 1ml. When larger canal volumes represent
either TM perforation or a very
large pars tensa retraction

42. 37
3. Acoustic (Stapedial) reflex Measurements
• A loud sound, 70-100dB above the threshold of hearing of a particular ear causes
bilateral contraction of the stapedial muscle which can be detected by
Tympanometry.
• In a normal ear, void of middle ear pathology, the reflex occurs at approximately
80-90 dB HTL.
Clinical applications of stapedial reflex
• Facial paralysis: present reflex implies that the lesion of the facial nerve is distal to
the branch that innervates the stapedius muscle.
• Otosclerosis
• Retrocochlear lesion: Abnormal reflex decay was used for the diagnosis of acoustic
neuroma.

43. 39
Causes of hearing problems in babies and
children
• glue ear – a build-up of fluid in the middle ear, which is common
in young children
• Congenital infections such as rubella or cytomegalovirus
• inherited conditions, such as otosclerosis, which stop the ears or
nerves from working properly
• damage to the cochlear or auditory nerves (which transmit hearing
signals to the brain); this could be caused by a severe head injury,
exposure to loud noise or head surgery, for example
• being starved of oxygen at birth (birth asphyxia)
• illnesses such as meningitis and encephalitis

44. 40
Assessment of Hearing in Older Children and
Adolescents
• Initial Otoscopic Examination
• Speech Test
• Loud
• Whisper
• Tuning Fork Tests
• Weber
• Rinne
• Schwabach
• Audiometry
• Speech audiometry
• Pure tone audiometry
• Tympanometry
• BERA
• EChocG
• OAE (Otoacoustic
Emission)

45. 4
1
Initial Otoscopic
Examination
• Performed with a hand
held otoscope
• Ear canal and tympanic
membrane are observed.
• Tympanic membrane is
seen for:
• Light reflection
• Differentiation of its part
• Mobility

46. 42
Speech Test
• Simplest of all
• Involves testing ability to hear
words without using any
visual information.
• Patient should repeat 5 words
spoken loudly at a distance of
approx. 5 metre.
• The whispered voice test
involves the tester blocking
one of patients ears and
testing hearing by whispering
words at varying volumes.

47. 43
Tuning Fork Tests
• Used to differentiate between conductive and sensorineural
hearing loss.
PRINCIPLE:
• CHL (OE or ME Disorder)
• Sounds delivered to the ear via AC will be
attenuated
• If the sound is delivered to the ear via BC,
bypassing the OE & ME, then the sound
will be heard normally assuming there is no
disorder
• SNHL (OE & ME Are Free From Disorders)
• Sounds delivered to the ear via BC will also
be attenuated
• Larger forks vibrate at slower frequency.
• Tuning forks with frequency 256 or 512 hz
are used

48. 44
Rinne Test & Weber Tests