UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• Dr. Juan Mora
• Consultant Audiological Physician
• and Paediatric Audiology Team
• Yorkhill Hospital, Glasgow
• October 2007

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• British Government commissioned a review on the
  role of neonatal hearing screening to detect
  congenital hearing loss.
• Doubts about the effectiveness of current
  screening program to detect congenital hearing
  loss.
• Availability of new technology in hearing
  screening.

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• Report published in 1997
• Review of the literature
• Evaluation of screening methods in use in UK
  (pre-school age)
• Study of costs of different screening options
• Visit to leading Audiology Dpts UK and US

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• Findings
• Epidemiology UK 840 children/year born with
  permanent hearing loss
• (40 dB HL or more in better ear 0.5-1-2-4 kHz)
• 400 not identified by 1 ½ years
• 200 not identified by 3 ½ years

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• Findings
• 2. Current practice in the UK
• A) Distraction test low sensitivity, relatively
  low specificity and yield
• Mean age of identification from 12 to 20
  months.
• In contrast data from the universal newborn
  screening programs Mean age of identification
• less than 2 months. (Yields 1 1.3 per
  1000)

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• Findings
• 2. Current practice in the UK
• B) Other local programs universal, high risk
  and early surveillance. Documentation and
  distribution of test results very deficient.

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• Findings
• Consequences of late identification
• Delayed speech and language development and
  poor communication strategies, with detrimental
  effect on education, mental health and quality of
  life.

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• Findings
• Cost UNHS associated with lesser cost per child
  screened and per child identified with hearing
  loss than the current Distraction Test program.
• --------------------------------------------------
  ---------
• IN 1999 THE UK NATIONAL SCREENING COMMITTEE
  AGREED TO A PROPOSAL FOR THE INTRODUCTION OF A
  NHSP.

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• SCREENING TOOLS
• OAEs OTOACOUSTIC EMISSIONS
• versus
• AABR AUTOMATED AUDITORY BRAINSTEM RESPONSES

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• OTOACOUSTIC EMISSIONS (OAEs)
• Prof. David Kemp (1978)
• A clinically feasible measure of cochlear (outer
  hair cell) function
• Normal OAEs recordable if normal (sensory)
  cochlear function
• OAEs abnormal even if mild degree of sensory
  hearing loss
• May be absent if external and middle ear
  abnormalities (impacted wax, glue ear)
• Relatively brief test time

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UNIVERSAL NEWBORN HEARING SCREENING
PROGRAMMENormal OAEs
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UNIVERSAL NEWBORN HEARING SCREENING
PROGRAMMEAbnormal OAEs
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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• AABR (Automated Auditory Brainstem Responses)
• Auditory Evoked Potentials asses the neural
  integrity of the auditory pathways from the eight
  cranial nerve to the cortex
• Auditory Brainstem Potentials From the distal
  part of the eight cranial nerve to lateral
  lemniscus and inferior colliculus
• AABR is an automated version used for newborn
  hearing screening, with responses influenced by
  glue ear not as much as OAEs, and slightly more
  complex and time consuming to perform test

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• OAEs versus AABR
• OAEs Sensitivity of nearly 100 but specificity
  82-87.
• For every 1000 babies tested 130 to 180
• will require further testing.
• AABR Sensitivity of 99.9 and specificity of
  gt95. Considerably less babies will require
  further testing.
• NEITHER OAEs nor AABR are hearing tests

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME
AABR - Natus Algo 3i
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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME
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UNIVERSAL NEWBORN HEARING SCREENING
PROGRAMMEREFER results from screening referred
for further assessment

• History and Clinical examination
• Auditory Brainstem Responses test
• (Click, Tone pips and Bone conducted clicks)
• High frequency tympanometry
• Otoacoustic Emissions test

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME
High frequency tympanometry (1 kHz)
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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME
Right Ear Click ABR
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UNIVERSAL NEWBORN HEARING SCREENING
PROGRAMMEOAEs
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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME
Outcome of Diagnostic Assessment Session

• Results consistent with bilateral normal hearing
  Baby discharged unless surveillance indicated.
• Results consistent with uni or bilateral hearing
  loss Baby referred to the doctor in the
  Audiology Team.

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• History
• Clinical examination
• Clinical findings and tests results explained
• Aetiological investigations outlined/requested
• Management plans outlined
• Referral to the Early Intervention/Support Team

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• Early Intervention/Support Team
• Audiologist
• Teacher for the hearing impaired
• Educational Audiologist
• Speech and Language Therapist
• Doctor
• Charity organisation (?)
• Social worker (?)

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UNIVERSAL NEWBORN HEARING SCREENING
PROGRAMMECase Study 1

• AABR REFER results bilaterally
• Diagnostic assessment session just the day before
  baby was 1 month old
• Tympanometry normal
• OAEs absent
• ABR gt90 dBnHL on AC clicks R L and gt90 dBnHL
  with 1 and 4 kHz

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UNIVERSAL NEWBORN HEARING SCREENING
PROGRAMMECase Study 1

• Uneventful pregnancy and normal delivery at term.
  Healthy neonate.
• Clinical examination normal.
• Second child of this family. Maternal parental
  grandparents both profoundly deaf, ascribed to
  meningitis and head injury very early in life.

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UNIVERSAL NEWBORN HEARING SCREENING
PROGRAMMECase Study 1

• Parents had counselling in the Dpt.
• Supported by Early Intervention Team
• ECG normal
• MRI ears/brain normal
• Genetics investigations
• Binaurally aided just before 4 months of age

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UNIVERSAL NEWBORN HEARING SCREENING
PROGRAMMECase Study 1

• GENETICS
• Mutation identified in both copies of Connexin 26
  gene AUTOSOMAL RECESSIVE NON SYNDROMIC HEARING
  LOSS
• IMPLICATIONS
• Genetic counselling to the parents
• Implications for aetiology of hearing loss in one
  of grandparents
• Possibility of carrier status of siblings of the
  babys parents and their children

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UNHS Case Study 2

• Born at 30 weeks of gestational age (one of
  quadruplets)
• AABR (UNHS) REFER in both ears
• No significant neonatal complications
• No FH of hearing loss in close relatives (her 3
  siblings had PASS results on AABR)

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Right cochlear microphonics
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Left cochlear microphonics
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UNHS Case Study 2

• Diagnosis is Auditory Neuropathy
• (Auditory Dys-synchrony)
• Poor correlation between ABR thresholds and Pure
  Tone Audiometry
• Poor correlation between Pure Tone Audiometry
  results and Speech and Language development

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UNIVERSAL NEWBORN HEARING SCREENING PROGRAMME

• SURVEILLANCE
• Be aware of the existence of late onset,
  progressive and acquired hearing losses.
• If there is a parental or professional concern
  regarding the hearing of a child, please refer to
  Audiology irrespective of the UNHS results.
• The babies with PASS screening results but risk
  factors for late onset or progressive loss need
  to be followed up.