Transcript ABR - National Center for Hearing Assessment and Management

NEWBORN INFANT SCREENING AND ASSESSMENT:
Emerging Technologies and Protocols
James W. Hall III, Ph.D.
Clinical Professor and Chair
Department of Communicative Disorders
College of Health Professions
University of Florida
Gainesville, Florida 32610-0174
[email protected]
Marion Downs
“Grandmother of Newborn Hearing Screening”
Year 2000 JCIH Position Statement:
Principles and Guidelines for Early Hearing
Detection and Intervention Programs
 JCIH = Joint Committee on Infant Hearing
 Published in:
 Audiology Today (Special Issue): August 2000, pp. 6-27
 American Journal of Audiology 9: 9-29, 2000.
 www.audiology.org
 Member organizations:
 American Academy of Audiology & ASHA
 American Academy of Otolaryngology-Head & Neck Surgery
 American Academy of Pediatrics
 Council on Education of the Deaf
 Directors of Speech and Hearing Programs in State and
Welfare Agencies
JCIH Risk Indicators for Hearing Impairment:
Birth to 29 Days
 Illness or condition requiring admission of > 48 hours to
an NICU.
 Stigmata or other findings associated with a syndrome
known to include a sensorineural or conductive hearing
loss.
 Family history of permanent childhood sensorineural
hearing loss
 Craniofacial anomalies, including those with
morphological abnormalities of pinna and ear canal
 In-utero infection such as cytomegalovirus, herpes,
toxoplasmosis, or rubella
JCIH Risk Indicators for Hearing Impairment:
29 Days to 2 Years (1)
 Parental or caregiver concern regarding hearing, speech,
language, and or developmental delay
 Family history of permanent childhood hearing loss
 Stigmata or other findings associated with a syndrome
known to include a sensorineural or conductive hearing
loss.
 Postnatal infections associated with sensorineural hearing
loss including bacterial meningitis
 In-utero infection such as cytomegalovirus, herpes,
toxoplasmosis, rubella, syphilis
JCIH Risk Indicators for Hearing Impairment:
29 Days to 2 Years (2)
 Neonatal indicators, specifically hyperbilirubinemia at a
serum level requiring exchange transfusion, persistent
pulmonary hypertension of the newborn associated with
mechanical ventilation, and conditions requiring
extracorporeal membrane oxygenation
 Syndromes associated with progressive hearing loss, such as
neurofibromatosis, osteopetrosis, and Usher’s syndrome
 Neurodegenerative disorders, such as Hunter syndrome, or
sensory motor neuropathies, such as Friedreich’s ataxia
 Head trauma
 Recurrent or persistent otitis media with effusion for at least 3
months
UNIVERSAL NEWBORN HEARING SCREENING:
Prevalence of Infant Hearing Loss in the U.S.A.
Category
Births Annually
Prevalence
Total Hearing Loss
Healthy
3,600,000
3/1000
10,800
At-risk
400,000
30/1000
12,000
Total
4,000,000
5.7/1000
22,800
Northern & Hayes, 1994
Universal Newborn Hearing Screening:
Turning Point in the United States of America
UNIVERSAL NEWBORN HEARING SCREENING:
Recent Events in the U.S.A.
 1975-1985: Hearing screening of at risk infants with ABR
 1993: National Institutes of Health Consensus Conference on Early
Identification of Hearing Impairment in Children
 1994: Joint Committee on Infant Hearing (JCIH) Position Statement
(recommending ABR and OAE techniques)
 1998: Yoshinaga-Itano et al. Language of early and later identified
children with hearing loss. Pediatrics 102.
 1999: American Academy of Pediatrics Task Force on Newborn and
Infant Hearing Screening: Diagnosis and intervention. Pediatrics
103.
 2000: JCIH Position Statement. Principles and Guidelines for Early
Hearing Detection & Intervention Programs.
UNIVERSAL NEWBORN HEARING SCREENING:
Converging Trends in 1990s
 Automated OAE and ABR devices manufactured for
newborn hearing screening
 Evidence of low “refer” rates (< 4%)
 Evidence of low false-positive rates (< 2%)
 Documentation of benefits of early intervention
(before 6 months)
 Successful implementation of UNHS in selected states
EARLY IDENTIFICATION OF AND INTERVENTION
FOR HEARING IMPAIRMENT IN CHILDREN
 "Hearing loss of 30dB HL and greater in the frequency region
important for speech recognition will interfere with the normal
development of speech and language.
 "Techniques used to assess hearing of infants must be capable
of detecting hearing loss of this degree in infants by age three
months and younger.
 Of the various approaches to newborn hearing assessment
currently available, two physiologic measures...auditory
brainstem response (ABR) and otoacoustic emissions
(OAE)...show good promise for achieving this goal"
Joint Committee on Infant Hearing 1994 Position Statement
Otoacoustic Emissions (OAEs)
NEWBORN HEARING SCREENING:
OTOACOUSTIC EMISSIONS
 Vohr et al. The Rhode Island Hearing Assessment Program:
Experience with statewide hearing screening (1993-1996). Journal
of Pediatrics 133: 353-357, 1998
 53,121 babies underwent screening (NICU =5130)
 average initial failure rate = 10%
 failure rate for rescreens at 2 to 6 weeks = 14.7%
 over failure (refer) rate = 1.2%
 111 infants identified with permanent hearing loss
 average age of intervention (amplification) = 5.7 months
Auditory Brainstem Response
(ABR)
PEDIATRIC AUDIOLOGY:
Auditory brainstem response (ABR)
0.5 uV
I
stimulus
click @
35 dB
electrodes
Auditory Evoked
Response System
(computer)
1974 - present
III
V
8 ms
UNIVERSAL NEWBORN HEARING SCREENING WITH AUTOMATED AUDITORY
BRAINSTEM RESPONSE (AABR): A MULTI-SITE INVESTIGATION
J Perinatology 20 ((8): S128, December 2000.
James W. Hall III, Ph.D.
University of Florida
Gainesville, Florida, U.S.A.
Dan Stewart, M.D.
Kosair Children’s Hospital
Louisville, Kentucky
Albert Mehl, M.D.
Boulder Community Hospital
Boulder, Colorado
Mark Carroll, M.S.
E.N.T. Associates
Huntsville, Alabama
Vicki Thomson, M.A.
Boulder Community Hospital
Boulder, Colorado
James Hamlett, M.D.
Baptist Memorial Hospital East
Memphis, Tennessee
NEWBORN HEARING SCREENING WITH AABR
Test Performance and Outcome
Refer % D/C
SITE
WBN
ICN
Boulder
98%
2%
2%
16%
2%
Louisville
>99%
<1%
1%
45%
.35%
Memphis
>99%
N=1
3%
13%
2.5%
Huntsville
93%
7%
1%
21%
.05%
Nashville
0%
100%
6%
32%
2%
2%
< 4%
28%
< 5%
0.9%
< 2%
N = 11,711
AAP
Refer Lost F/U
False Pos
Combination Device for Newborn Hearing
Screening and Diagnosis with OAEs and ABR:
AudioScreener by Grason Stadler
Rationale for Combined OAE/ABR Screening
 In ear calibration of signal intensity (OAE and ABR)
 Lower refer (< 2%) and false-positive rates (< 0. 2%)
 Minimal parental anxiety
 Fewer diagnostic follow-ups with lower costs
 Less hearing impaired infants lost to follow-up
 Differentiation of conductive vs. sensory vs. neural
auditory dysfunction
 Quicker and more appropriate management
 Identification of auditory neuropathy
 Earlier identification of hearing impairment
Early Identification and Intervention for Hearing
Impairment in Children: Important Steps
Pass?
Parent
Info
Progressive
factor?
Screening with AABR or OAE
before hospital discharge
Fail?
Secondary screening
within 3 months (optional)
Diagnostic audiometry
to define hearing loss
Hearing aid fitting and
habilitation (by 6 mos.)
Hearing
loss?
Year 2000 JCIH Position Statement:
Protocol for Confirmation of Hearing Loss
In Infants and Toddlers (0 to 6 months)
 Child and family history
 Otoacoustic emissions
 ABR during initial evaluation to confirm type, degree &
configuration of hearing loss (ASSR?)
 Acoustic immittance measures (including acoustic reflexes)
 Behavioral response audiometry (if feasible)
Visual reinforcement audiometry or
Conditioned play audiometry
Speech detection and recognition
 Parental report of auditory & visual behaviors
 Screening of infant’s communication milestones
Estimation of Frequency-Specific Auditory Thresholds
with Tone Burst ABRs: Initial Data Points for DSL
Auditory brainstem response (ABR):
0.5 uV
I
Tone-burst
signals
electrodes
Auditory Evoked
Response System
(computer)
ABR mature by 18 months
III
V
8 ms
FREQUENCY-SPECIFIC ABRs:
Tone Burst Test Protocols
Click versus Tone Burst ABRs
I
III
V
click
I
50
III
V
1000 Hz
V
500 Hz
0
15 msec
Stimulus
Analysis Time
FREQUENCY-SPECIFIC AUDITORY BRAINSTEM
RESPONSE (ABR): Relation to Audiogram
(Oates & Stapells, 1998)
ELECTROPHYSIOLOGIC ASSESSMENT OF AUDITORY FUNCTION
IN INFANTS CASE REPORT:
ABR Estimated Audiogram
Auditory Steady-State Response (ASSR):
General Principles
 An electrophysiologic response, similar to ABR.
 Instrumentation includes:
 Insert earphones
 Surface electrodes
 Averaging computer
 Stimuli are pure tones (frequency specific, steady state signals)
activating cochlea and CNS
 ASSR is generated by rapid modulation of “carrier” pure tone
amplitude (AM) or frequency (FM).
 Signal intensity can be as high as 120 dB HL
 ASSR phase or frequency is detected automatically (vs. visual
detection)
Auditory Steady State Response (ASSR):
Clinical Devices
 GSI VIASYS
 Audera
 Descendant of Melbourne Australia system Field
(Rickards, Gary Rance, Barbara Cone-Wesson, et al)
 Bio-Logic Systems Inc.
 MASTER
 Descendent of Canadian system
(Terry Picton et al)
ASSR:
2000 Hz tone modulated at rate of 100 Hz
Modulated carrier
amplitude
2
1
0
-10.00
5.00
10.00
15.00
-2
msec
20.00
25.00
ASSR:
Response imbedded within EEG
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
0
10
20
30
40
50
ms
60
70
80
90
100
ASSR: Graphic display in vector plot of EEG
samples at modulation frequency
B
c’
a’
A
Vector length (c’) =
magnitude of activity
b’
C
Vector angle (a’) = phase
lag between stimulus
MF and EEG at MF
ASSR (Audera):
Significant phase coherence
ASSR (Audera):
Estimated Audiogram
Pure Tones vs. ASSR: Case 1 (child)
.50 1K 2K 3K 4K
6K
8K
dBHL
.50 1K 2K 3K 4K
20
40
60
80
100
Frequency in Hz
PT
ABR
ASSR
Frequency in Hz
6K
8K
ABR vs. ASSR: Case 4 (infant)
.50 1K 2K 3K 4K
6K
8K
dBHL
.50 1K 2K 3K 4K
20
40
60
80
100
Frequency in Hz
PT
ABR
ASSR
Frequency in Hz
6K 8K
Limitation of Tone Burst ABR in
Severe-to-Profound Hearing Loss
.50 1K 2K 3K 4K
6K
8K dB HL
.50 1K 2K 3K 4K
6K 8K
20
40
60
80
No ABR > 80 dB HL
Frequency in Hz
100
AC
BC
No ASSR > 120 dB HL
Frequency in Hz
Estimation of Frequency-Specific Auditory Thresholds
with Auditory Electrophysiology: DSL Hearing Aid Fitting
Early Intervention for Infant Hearing Impairment:
Amplification
Management of Infant Hearing Loss:
Cochlear Implants
Newborn Hearing Screening and Assessment:
Conclusions
 Universal newborn hearing screening is feasible with
automated OAE and ABR technology
 Estimation of hearing thresholds (audiogram) is possible
in infants with electrophysiologic techniques
 ABRs evoked by tone burst stimuli
 Auditory steady-state response (ASSR)
 Intervention with hearing aids can be implemented early
(before 6 months)
 Cochlear implant candidacy can be determined during
infancy
 Early intervention leads to normal language development