Download Hearing - PKS Kids

James Zeigler Au.D.
Thank You
 Protocol for screening and evaluating hearing loss in
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infants and young children
Conductive and sensorineural hearing losses
Amount of hearing loss
Audiogram overview
Hearing Tests - abr and sound booth tests
Hearing Aids
JCIH 2007
www.jcih.org
Early Hearing Detection and
Intervention (EHDI): What is it?
 Hearing loss is the most common disorder
screened in the newborn period and one of the
most cost effective to treat
 EHDI is an integrated system that brings
multiple disciplines together for the single
purpose of detecting and treating hearing loss as
early in life as possible
 There must be a seamless integration of
universal newborn screening, prompt diagnosis,
effective intervention and tracking.
EHDI Program Goals
• Screen all newborns by 1 month of age
• Diagnose hearing loss by 3 months of age
• Link the child to intervention by 6 months
of age to maximize developmental,
educational and communication outcomes
• Provide support and education for families
about the importance of detection and
treatment of newborn hearing loss
Remember!! 1 - 3 - 6
Why the rush??
Anu Sharma Ph.D.
Cortical Auditory Potentials
Boys Town National Research Hospital Study of
Earlier vs. Later
 129 deaf and hard-of-hearing children
assessed 2x each year
6
Identified <6 mos (n = 25)
Identified >6 mos (n = 104)
Language Age (yrs)
5
4
3
2
1
0
0.8
1.2
1.8
2.2
2.8
Age (yrs)
3.2
3.8
Moeller, M.P. (1997). Personal communication , [email protected]
4.2
4.8
Anatomy and Physiology
Anatomy and Physiology
of Hearing
Divided into 4 parts
 Outer Ear
 Middle Ear
 Inner Ear
 Central Auditory Nervous System
Structures of the Outer Ear
Pinna
 Gathers sound
waves
 Aids in
localization
Structures of the Outer Ear
External Auditory
Canal or Ear Canal
 Approx. 1 inch long
 “S” shaped
 Amplifies sound by 3 to 6
dB
 Isolates the eardrum from
physical damage
 Cerumen glands
moisten/soften skin
 Presence of some
cerumen is normal
Structures of the Outer Ear
Tympanic Membrane
or Ear Drum
 Thin membrane
 Forms boundary
between outer and
middle ear
 Vibrates in
response to sound
waves
 Changes acoustical
energy into
mechanical energy
Structures of the Middle Ear
Ossicles
 Ossicular chain = malleus,
incus & stapes
 Focus/amplify vibration of
TM to smaller area
 Enables vibration of
cochlear fluids
 Malleus = Hammer
 Attaches to TM
 Incus = Anvil
 Connector
 Stapes = Stirrup
 Smallest bone in the
body
 Footplate inserts in
oval window of the
cochlea
Structures of the Middle Ear
Eustachian Tube
 Connects middle ear
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cavity to nasopharynx
“Equalizes” air pressure
in middle ear
Normally closed, opens
under certain conditions
May allow a pathway for
infection
Children “grow out of”
most middle ear
problems as this tube
lengthens and becomes
more vertical
PKS and high arch
palate?
Structures of the Inner Ear
Cochlea
 Snail shaped cavity
within mastoid bone
 2 ½ turns
 3 fluid-filled
chambers
 Contains Organ of
Corti
 Converts mechanical
energy to neuroelectrical energy
Structures of the Inner Ear
Organ Of Corti
 End organ of
hearing
 3 rows of Outer
Hair Cells
 1 row of Inner Hair
Cells
 Tectorial and
Basilar Membranes
 Cochlear fluids
(From Augustana College, “Virtual Tour of the Ear”)
Structures of the Inner Ear
Hair Cells
 Frequency specific
 Low pitches = apex of
cochlea
 High pitches = base
of cochlea
 Fluid movement causes
deflection of nerve
endings
 Nerve impulses
(electrical energy) are
generated and sent to
the brain
Structures of the Central Auditory System
VIIIth Cranial Nerve or
Auditory Nerve
 Bundle of nerve fibers (2530K)
 Travels from cochlea through
internal auditory meatus to
skull cavity and brain stem
 Carry signals from cochlea to
primary auditory cortex,
with continuous processing
along the way
Structures of the Central Auditory System
Auditory Cortex
 Wernicke’s Area within
Temporal Lobe of the
brain
 Sounds interpreted
based on
experience/association
Anatomy of Hearing Loss
Site of
Conductive
Loss
Site of Sensorineural Loss
Types of Hearing Loss
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Conductive = Outer and/or Middle Ear
Sensorineural = Inner Ear
Mixed = Outer and/or Middle Ear and Inner Ear
Auditory Neuropathy Spectrum Disorder (AKA
Auditory Neuropathy / Dys-synchrony) =
Central Auditory System
 Unilateral
 Bilateral
Deciphering the Audiogram
Horizontal axis: Frequency information (pitch)
Deciphering the Audiogram
Vertical axis: Sound energy (loudness)
Frequency Low Pitch to High Pitch
Loudness
Soft to Loud
Normal Hearing
Mild Loss
Moderate Loss
Moderate Severe Loss
Severe Loss
Profound Loss
Audiogram of Familiar Sounds
Plotting Results on an Audiogram
White area is inaudible
Tan area is audible
From: Glen R. Meier, M.S., CCC-A, FAAA
http://www.audiologyawareness.com/hea
rinfo_audiogramread.asp
Conductive Hearing Loss (CHL)
 Caused by damage, disease, or malformation of the
outer or middle ear
 Sound is prevented from reaching the inner ear
 Sound perceived as muffled or weak
Conductive Hearing Loss
Sensorineural Hearing Loss (SNHL)
 Caused by damage, disease, or malformation of the
inner ear
 Sensory loss associated with inner ear damage
 Neural loss if hearing nerve cannot send the impulse to
the brain
 Sound perceived as distorted AND weak
Sensorineural Hearing Loss
Hearing loss and Prosthesis
Simulator
HeLPS
Demo #1 Severity of sensorineural hearing loss
http://www.sens.com/helps/helps_d01.htm
Demo # 3 Mild Conductive and Mild Sensorineural
hearing loss comparison
http://www.sens.com/helps/helps_d03.htm -
Hearing Test Categories
 Objective tests or physiologic tests
 Do not require child's participation
 Subjective tests
 Require the child to participate in evaluation
Types of Subjective Auditory Tests
Sound Booth Tests
 Visual Reinforcement Audiometry (VRA)
 Play Audiometry
 Conventional Audiometry
 Hearing for Speech
 All subjective tests evaluate HEARING: requires
consistent responses from the child
Types of Objective Auditory Tests
 Tympanometry - middle ear
 Otoacoustic Emissions (OAEs) -
inner ear
 Auditory Brainstem Response (ABR)
-auditory pathways in brainstem
DO NOT evaluate Hearing
Tympanometry
 Special earplug placed in the ear canal produces a puff
of air
 The technique measures the response of the eardrum
to the change in air pressure
 Tympanometry evaluates only the middle ear and does
not provide information about hearing
 Used to determine if (temporary) middle ear
abnormality contributes to hearing loss
Otoacoustic Emissions (OAEs)
 Special earphones placed into the ear that deliver
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clicking sound within the ear canal
Cochlea responds by producing a sound
Probe detects this cochlear emission, which is
recorded on computer
OAEs detect presence or absence of hearing loss, but
cannot assess degree of hearing impairment
Method for newborn hearing screening
Auditory Brainstem Response (ABR)
 Special earphones deliver sound to ear
 Electrodes on the scalp measure brain activity in
response to sound
 Resulting waves provide information on the integrity
of the neural pathway
 ABRs can estimate degree of hearing loss at different
frequencies
 Used for infants and children who cannot consistently
respond to subjective testing
JCIH - Changes in 2007
Audiologic Evaluation
 Should be performed by audiologists
experienced in pediatric hearing assessment
 Initial audiologic test battery to confirm hearing
loss must include:
 physiologic measures – objective tests
 when developmentally appropriate, behavioral
methods
 Completed in both ears regardless of the results of
screening tests
JCIH 2007
Audiologic Evaluation – Birth to 6 months (Developmental Age)
 Child and family history
 Frequency-specific AC (air conduction) ABR;
 Bone conduction, frequency specific ABR, when indicated
 Click-evoked ABR
 if infant has risk indicators for neural HL,
 any infant demonstrating no response on FS-ABR requires clickevoked ABR
 OAE (DPOAE or TEOAE)
 Tympanometry using 1000-Hz probe tone
 Observation of auditory behavior
 As cross-check; not for assessment or amplification fitting
JCIH 2007
Audiologic Evaluation – 6 months to 36 months
 Child and family history
 Parent report of auditory and visual behaviors and
communication milestones
 Behavioral audiometry (VRA, CPA), including:
 Pure-tone audiometry across the frequency range for each ear
 Speech detection and speech recognition measures
 OAE testing
 Tympanometry & Acoustic Reflex Thresholds
 ABR testing if responses to behavioral audiometry are not
reliable, OR if ABR testing has not been performed previously
JCIH 2007
Amplification
Infants diagnosed with permanent
hearing loss should be fit with
amplification within one month of
confirmation of hearing loss
Treatment and intervention for
hearing loss
Medical intervention
surgical treatment
treatment for chronic middle ear
disorder
Hearing aids
Cochlear implants
FM systems
Treatment and intervention for
hearing loss
 Early intervention for overall development
 Communication modalities
 Emotional
 Social
 Cognitive
 Who
 Early interventionists
 Speech-language therapists – specialized in hearing
impairment
 Educators for the hearing impaired
Monitoring and managing hearing
loss
 Hearing can change – can get worse
 Plan for future needs - amplification flexibility
 Monitor hearing aid/cochlear implant function –
trouble shoot
 Provide educational input and
consultation (classroom modifications,
FMs, educational strategies)
How to work collaboratively with
audiologists
Out reach efforts can be individual or group
Mutual information sharing
Keep asking questions
Take Home Message
 Infants can and should be assessed as soon as possible
to maximize development of maturing auditory skills;
sets the stage for language development
 Family choices for intervention often includes hearing
aids/cochlear implants AND early intervention
(communication strategies)
 Questions about hearing? Ask your Audiologist
Resources
You tube video on hearing:
Brandon Pletsch
http://www.youtube.com/watch?v=PeTriGTENoc&NR=1
Hearing screening information for parents:
www.babyhearing.org
American Speech,Language and Hearing Association
www.asha.org
American Academy of Audiology
www.audiology.org
Pennsylvania Early Hearing Detection and Intervention
www.paearlyhearing.org
• Contact information: [email protected]
Thank You!