This document discusses evaluation and management of deaf children. It begins by defining different types and degrees of childhood hearing loss. Early diagnosis is important as it allows for early intervention, which research shows improves outcomes for language development and education. Universal newborn hearing screening within the first 3 months of life is now standard practice. Diagnostic tests include otoacoustic emissions testing and auditory brainstem response testing. Causes of childhood hearing loss can be genetic syndromic or non-syndromic causes. Proper evaluation involves history, physical exam, and potential genetic or imaging studies to determine the etiology.
3. IDEA (Individuals with Disabilities Education Act) 2007 defines
hearing loss:
- Deaf child is one who cannot understand spoken communication
even with a hearing aid.
- A hard of hearing child is one who can hear spoken
communication, but this does not necessarily mean that he
understands it.
Definition
4. ďPermanent childhood hearing impairment (PCHI): confirmed
permanent B/L hearing impairment exceeding 40 dBHL (average
of pure tone thresholds at 0.5,1,2 & 4 kHz in better hearing ear).
ďCongenital or acquired
ďPrelingual deafness Vs postlingual deafness
-for the childâs education and management
5. Degree of hearing loss
ďŽ0-15 dB Normal
ďŽ15-25 Minimal Hearing Loss
ďŽ26-40 Mild Hearing Loss
ďŽ41-55 Moderate Hearing Loss
ďŽ56-70 Moderately Severe Loss
ďŽ71-90 Severe Hearing Loss
ďŽ>90 dB Profound Hearing Loss
(Categories from the National Institutes of Health)
http://www.nih.gov/
6.
7. Epidemiology
ďOne child in 1000 born - bilateral permanent
childhood hearing impairment(PCHI)
-About 60% of these children= mod. Hearing loss
(41-60 dBHL)
-Remainder have severe (61-80 dBHL) or profound
(>81dBHL)
(www.who.int/pbd/deafness/hearing_impairmencgrades/ en/index)
ďThe prevalence of PCHI increases with ageď further
1 in 1000 develop acquired or progressive hearing
impairment. (Fortnum et al., 2001)
8. ďPCHI â one of the most common abnormality present at birth
ďThe prevalence of hearing loss- greater than that of most other
diseases and syndromes (eg, phenylketonuria, sickle cell disease)
screened at birth.
9. ďTwo thirds of people with moderate to severe hearing impairment
live in developing countries.
ďIn developing countries-infection
congenital- rubella and CMV
acquired â mumps, measles, meningitis & COM
ďIn developed countries- about half of PCHIâgenetic cause
(www.who.int)
10. Terminology:
ďBilateral Permanent childhood hearing loss (PCHL)
- Hearing loss >40 dB at (0.5k,1k,2k,4k ) â better ear
- 60 % childrenâmod CHL
ďAcquired/Late onset permanent hearing loss
- Postnatal/after birth
ďUnilateral permanent hearing loss
- Inability to hear from deaf side
- Difficulty â hearing â speech in noise
- Poor localization of sound
11. ďŽAuditory neuropathy/ Dyssynchrony (AN/AD)
- Damage to inner hair cells, synaptic junction, auditory
neurons in spiral ganglion
- Clinical test: normal OAE/ absent or abnormal ABR
- 10 % children - confirmed PCHL - Auditory neuropathy
- Found predominantly in NICU population
ďŽ Temporary childhood hearing loss
- OME â extremely common
- Major risk factors â season, passive smoking, bottle feed
URTI, NICU admission
- Speech and language delay
12. The High-Risk Register (HRR)
ďPrior to implementation of universal newborn hearing screening
ďInfants identified at high risk for hearing loss â high risk register
(HRR)ď screened
The risk factors for newborn:
(Joint Committee on Infant Hearing (JCIH) 2000 Position Statement)
ďFamily h/o permanent childhood sensorineural hearing loss
ďIn utero infection - cytomegalovirus, rubella, toxoplasmosis or herpes
ďCraniofacial anomalies- morphological abnormalities of the pinna & EAC
ďNeonatal indicators - hyperbilirubinemia, persistent pulmonary
hypertension of the newborn (PPHN), mechanical ventilation
ďPostnatal infections - bacterial meningitis
13. ďStigmata/ findingsď syndrome - SNHL or CHL or Eustachian tube
dysfunction
ďParental or caregiver concern regarding hearing, speech, language,
and/or developmental delay
ďHead trauma
ďRecurrent or persistent otitis media with effusion lasting for at least 3
months
ďScreening by high risk register alone can only identify 15-20% of
new born babies requiring help (NIH, 1993)
14. ďPrior to implementation of universal newborn screening - testing
conducted only on infants meeting the criteria of the high-risk register
(HRR).
ďHRR - as many as 50% of infants born with hearing loss have no
known risk factors.
ď Reliable screening tests available- minimizes referral rates and
maximize sensitivity and specificity.
15. Universal newborn hearing screening (UNHS)
ďŽNational Institute for deafness and other communicative disorders (NIDCD)
- consensus conference â on early identification of hearing loss â 1993
ďŽRecommended â UNHS
- Screening 1st three months of life
- Taken up by various agencies â
American academy of otolaryngology- HNS
American academy of speech and language
American academy of audiology
â˘âPassâ or âRefer,â
â˘âReferâ â
follow up testing
confirmed ď referral to otolaryngologist
16. Initially â
- In 1988 -hearing loss identified in children in the USA- 2.5 yrs
- Severe to profound hearing loss or with multiple disabilities identified at or
before age 2.5 yrs
- Mild-to-moderate: not identified until school
Universal newborn hearing screening program 1997-2001
Mean age of diagnosis - 3.9 months
Mean age of intervention - 6.1 months (Connolly et al., 2005)
Efficacy of Early Identification and Intervention
17. ďDefinition of early identification and intervention - evolved over the
years
ďEarly identification -defined as intervention before the age of 18
months
ďThe implementation of universal screening programs ď definition of
early identification and intervention re-examined
ď Early identification - diagnosis as early as age 3 months
ďEarly intervention - by age 6 months
18. ďBetter language scores in severe- profound deaf children- hearing loss
identified at an average age of 11.9 months, compared to 19.5 months
(White SJ and White RE, 1987)
ďChildren identified and wore hearing aids by the age of 6 monthsď
acquired vocal communicative and linguistic skills better than children
identified at a later age (Robinshaw HM, 1995)
ďCritical period of early identification & intervention- younger than 6 months
(Yoshinago et al., 1998)
19. ďThe ability to hear during the early years of life is critical
for the development of speech, language & cognition
ďInfants who are not identified before 6 monthsď delay in
speech and language development
ďIntervention at or before 6 monthsď child with impaired
hearing to develop normal speech and language, alongside
his or her hearing peers
ďEarly identification-development of expressive, receptive
language, cognition, behaviour, personality development
(Davis et al., 1992)
20. Delayed Diagnosis
ďPermanently impaired speech and language skills
ďReduced intellectual ability
ďLowered adult earnings
ďMore limited social skill development
21. (Joint Committee on Infant Hearing (JCIH) 2007 Position Statement)
1. Definition of targeted hearing loss expanded to include neural hearing loss
(eg. auditory neuropathy/dyssynchrony)
2. Separate protocols for neonatal intensive care units (NICUs) and well-baby
nurseries. ABR screenings for all NICU babies, as well as babies admitted for
>5 daysď neural hearing loss will not be missed.
3. Referrals for all infants who do not pass ABR screening in the NICU.
4. Rescreening of all infants should include re-evaluation of both ears, even if the
infant only failed one ear in the initial screening.
5. Audiologists with expertise in evaluating newborns should conduct diagnostic
evaluations.
22. (Joint Committee on Infant Hearing (JCIH) 2007 Position Statement)
6. Children identified with hearing loss ď fit amplification within 1 month of
diagnosis.
7. A genetics consultation to families of infants with hearing loss.
8. Children with hearing loss should ď evaluation by an otolaryngologist &
ophthalmologist.
9. Children with any degree of bilateral or unilateral hearing loss ď consider early
intervention services
10. Families ď all communication options and available hearing technologies
11. Early intervention services ď by professionals with expertise in hearing loss
23. Methods of Screening
Otoacoustic emission (OAE)
Principle:-Response of outer hair cells to acoustic stimuli
- Assess cochlear integrity
- Fast test for normal preneural cochlear function
Set up:
- Probe assembly in EAC
- Tonal / click stimuli â delivered
- OAE - generated by cochlea
- Measured â microphone
24. If middle ear normalď assesses cochlear function in
frequency range 0.5-6kHz
-Fast, efficient, frequency specific
Limitations:
- Efficacy reduced by contamination of low frequency
noise in busy nursery, wax/debris in EAC
- Middle ear pathology
- Auditory neuropathy-OAE may be normalď ABR
- Stay in NICU >5 daysď ABR
25. ďŽAutomated ABR (AABR):
- Auditory function from 8th nerve ď auditory brainstem
Set upâ
-Electrodes - forehead, mastoid, nape of neck
-Click stimuli â in the canal earphone - 35 dB
-Compare infantâs waveform - normative ABR infant data
-Response â pass / fail
-Screening tool - < 6 months
26. Advantages:
â˘Can be done â with background noise
â˘No interpretation required
â˘Solely-screening technique ď identify infants,
who require follow up testing
Disadvantages:
â˘Lacks frequency specific information
â˘Canât differentiate type/degree of hearing loss
â˘Requires increased preparation time prior to test
27. Diagnostic auditory brainstem reflex:
-Not used in UNHS because of length of
procedure, cost, audiologist
-Unlike AABR-35 dB, Intensity of stimuli â
varied â manual ABR
-Allows to know â severity of hearing loss
-Type of hearing loss
-Not used for screening but for follow up
28. Follow â up testing
ďInfants who do not âpassâ ď F/U at 1 month
interval
ďF/U allowsď multiple testing sessions, medical
intervention, parental counseling, appropriate
amplification before age of 6 months
ďIf f/u delayed â need for sedation increases
ďIf infant fail 2nd screening session â diagnostic
ABR/ OAE
ďAuditory neuropathy/dyssynchrony- Normal OAE
but abnormal ABR
31. Syndromic hearing loss
Dominant
Waardenburg
BOR
Sticklerâs
NF2
Treacher Collins
Recessive
Usher
Pendred
Jervell/Lange-Nielsen
X-linked
Alport
Mitochondrial
Chromosomal
Down Syndrome
Non syndromic hearing loss
75% Recessive
23% Dominant
2% X-linked
1% Mitochondrial
1/3 syndromic 2/3 nonsyndromic
32. Disabilities that occur with deafness (%)
Deafness with
No Other Disabilities
60.1
Learning Disability 10.7
Intellectual Disability 9.8
Attention Deficit Disorder (ADD/ADHD) 6.6
Blindness and Low Vision 3.9
Cerebral Palsy 3.4
Emotional Disturbance 1.7
Other conditions 12.1
(Gallaudet Research Institute, Jan 2003)
33. Syndromic hearing loss
⢠Pendred
⢠Usher
⢠Branchio-oto-renal
⢠Waardenburg
⢠Jervell and Lange-Nielsen
⢠Alport
⢠CHARGE association
34. Non syndromic hearing loss
⢠Isolated genetic HL without
any other recognized
abnormalities
⢠Two thirds of all congenital
SNHL
⢠Over 50 genes; new ones
discovered every year
⢠Testing available for only a
small few
35. Connexin 26 (GJB2)
ďMost common hereditary SNHL
ďCauses 50% of non-syndromic SNHL in the
US and Europe.
ďRecessive inheritance
ď35delG â extremely common (2.5% carrier
rate)
ďSNHL variable (severity, symmetry,
progression).
ďGenetic testing widely available
36. Inner ear malformations
ď 30- 35% of patients with SNHL - have malformations
ď Even higher % in unilateral SNHL
ď Malformations can occur in isolation, or as part of a
syndrome
ď Why is diagnosis important?
Risk of meningitis
Risk of progression of HL
Complicates cochlear implantation
37. ď Michel aplasia: most severe, complete absence of
bony & membranous labyrinth
ď Mondiniâs aplasia: only basal coil present
ď Sheibeâs (cochleosaccular)dysplasia: most
common, dysplasia in cochlea & saccule
ď Bing-Siebenman dysplasia: complete absence of
membranous labyrinth but bony labyrinth
present
ď Alexanderâs dysplasia: Limited cochlear duct
differentiation at the level of the basal coil
ď Enlarged vestibular aqueduct: early onset SNHL,
progressive
ď Semicircular canal malformations
38. Evaluation
History:
Presentation depends on:
- Degree of hearing loss
- Patientâs age
- When hearing loss began ?
- Threshold of suspicion by parents
- Presence of identifiable risk factors
2/3 rd cases - parentâs 1st suspicion
10 % cases - Paediatrician
15 % cases - health caregivers
Meantime b/w 1st suspicion and diagnosis â 9 months
39. Evaluation of hearing loss:
ďConcern over childâs hearing
ďBehavioural problems/personality defects
ďCongenital/postnatal - profound deafness - loss
of cooing by age of 6â9 months
ďMinor speech impediments, school failure
ďMental retardation, autism, attention deficits,
adjustment disorders
40. History & Physical Examination
ď History:
Characterize onset
Identify risk factors and exposures
Identify family history of SNHL
â˘Infections, other systemic diseases
â˘Trauma, infections, diabetes, blood dyscrasias,
autoimmune, malignancy, meningitis, middle ear
disease, noise exposure
â˘Balance problems, learning problems, speech
delay
â˘Any prior testing
-Changes, progression, fluctuation
â˘Other symptoms- Visual, balance, tinnitus
41. Important Elements
ďPerinatal history
ďFamily history
ďNeonatal history
â˘Prematurity
â˘NICU
â˘Mechanical ventilation
â˘Infections
â˘Hyperbilirubinemia (transfused ?)
â˘TORCHS/maternal infections
42. Physical Examination
ď Usually normal
ď Detect syndromic features
â Pigment anomalies (Waardenburg)
â Ear pits, branchial anomalies (BOR)
â Abnormal external ear (CHARGE, BOR)
â Craniofacial abnormalities
â ď Pinna
- Microtia
- Canal atresia
45. Aim of aetiological investigations
Aim:
- Try answer parents â âwhy is my child deaf ? â
- Identify and treat medical conditions
- Assist early decision making
Appropriate communication modes
Educational placement & counselling
- To inform genetic counselling
- Epidemiological research
46. Laboratory Studies
â˘Depending - patient's history & physical findingsď biochemical
evidence
â˘Diagnosis of SNHL -
â˘Testing thyroid function, measuring BUN and creatinine levels and urinalysis.
â˘ECG - diagnosing â arrhythmia- Jervell Lange-Nielsen syndrome
⢠B/L hearing loss - (eg, ESR)
â˘Autoimmune inner ear disease
â˘Genetic screen
47. â˘Serology (suspected viral, autoimmune, syphilitic)
â˘CBC
Risk of thalassemia or sickle cell disease
Macro thrombocytopenia & leukocyte inclusions (a/w Alport syndrome)
â˘Biochemistry
BUN & electrolyte abnormalities with renal dysfunction (e.g., Alport syndrome)
Lipid profile
Glucose
â˘Thyroid function tests
Congenital or acquired hypothyroidism
Pendred syndrome
â˘Autoimmune work-up
ESR
Immunoglobulin
Complement
48. ⢠Non-contrast CT of temporal bone
Gold standard
Quick but may require sedation
Involves ionizing radiation
Excellent for almost all causes
⢠MRI
Detect abnormality of CNS
Certainly indicated in some unusual cases
(Russo et al., 2006)
50. Arousal test:
Sound stimuli ď light sleepď arousal
Auditory response cradle(ARC):
Baby in cradle-behaviour in response to sound
stimulusď trunk & limb movement, head jerk and
respiration
Assessment of hearing
51. Audiometric Evaluation: when & what to do ?
Electrophysiological testing:
- Key developmental age: 0 â 6 months
- Mainly employed â Newborn screening
- Preschool screening /surveillance
- Diagnostic testing â 1st 6 months
(Sininger et al., 2003)
Also used -BOA fails to give reliable results
- Confirm hearing threshold â prior fitting hearing
aid /cochlear implant
52. Behavioural observation audiometry (BOA):
Key developmental age: 0 â 6 months
⢠Sound stimuliď response ď change in behaviour e.g., alerting,
widening of eyes or facial grimacing, arousal from sleep
â˘Auropalpebral reflex
â˘Moro reflex:
â˘Cessation reflex: cessation of an activity
â˘Use < 6 months â superseded by â OAE,ABR
53. Infant distraction test (IDT):
Key developmental age: 6â18 months
Normal response: Sound ď head turn to
locate the source of sound
Visual Reinforcement audiometry (VRA):
-Key development age â 6 to 36 months
-Conditioning technique
-Child trained to look for an auditory
stimulus by turning head-reinforced by
flashing light or toy
54. Performance testing:
-Key developmental age: 2-5 yrs
-Used till cooperation with PTA achieved
-Child conditioned to wait for a sound ď respond ď
play activity
-Determine â minimal threshold response
Pure tone audiometry(PTA):
-Key developmental age: > 3yrs
-Instructed to raise the corresponding hand - sound is
heard
-CHL and SNHL can be differentiated
-Quick and easy screening test - effective tool in
schools
-Disadvantages: formal evaluation takes time/
equipment
fully performed only -older, cooperative patients
58. Algorithm
1. Known or suspected aetiology (e.g. meningitis, trauma):
a. At diagnosis:
â˘Ophthalmology
â˘Additional tests and/ or treatments only as
clinically indicated by aetiology or clinical course
b. Serial Audiograms
59. 2. Unilateral SNHL:
a. At diagnosis:
â˘Imaging study
â˘Ophthalmology
b. If imaging normalď consider Genetics referral
c. Serial Audiograms
60. 3. Bilateral SNHL (unknown aetiology)
a. At diagnosis:
â˘Imaging of temporal bone
â˘Ophthalmology
â˘Genetics referral (ideally, specialist in HL)
â˘EKG
â˘UA
â˘Labs if clinically indicated (rarely)
b. Serial Audiograms, other referrals
62. Management of associated disorders
⢠Cardiac (prolonged QT) â awareness, medication
⢠Meningitis vaccinations:
â SNHL population, particularly those with
malformations, at higher risk than general population
⢠Thyroid disease
⢠Meningitis â steroids reduce the incidence of SNHL and
improve survival
⢠Sudden SNHL â high dose steroids +/- antivirals may
improve recovery of hearing if begun promptly
(controversy)
63. Management
Deafnessď heavy social & economic burden on individual, family,
community & country
Multidisciplinary approach:
Parentsâ reaction to the diagnosis:
-Shock, denial, anger, acceptance
-Dealt sympathetically
Subsequent management of the hearing impaired child:
1.Appropriate hearing aid selection
2.Promotion of the development of language & communication skills
and if possible, speech development
64. Management
Medical:
CHL: - Otitis media or its sequelae
- Otitis media with persistent effusion >3 months
- Obstruction of EAC
- If hearing loss continues ď amplification
- hearing aid
- speech therapy
SNHL:
- Canât be medically treated
- Amplification with hearing aids
- Speech therapy may be beneficial
65. Surgical management:
-Some causes of CHL
-Persistent chronic or recurrent otitis media
-Cholesteatoma
-Bone-anchored hearing aid (BAHA):
- Microtia
- Anotia - auricular reconstruction
- Persistent otorrhea
ď SNHL can not be treated with surgical means other than cochlear
implantation
66. Hearing aids
⢠SNHLď canât be corrected to normal by any form of medical or
surgical Rx
⢠Some CHL- congenital abnormalities of the EAC & middle ear ď not
suitable for surgical Rx
⢠Birth of totally deaf child-rareď high powered hearing aids for
residual hearing
⢠Types of hearing aids:
(I) Personal hearing aids: body worn aids, behind the ear aids, BAHA
(II) Aids not entirely worn by the listener: speech trainer, group hearing
aids, Radio (FM) hearing aids, infrared hearing aid system, loop
system
67.
68. Cochlear Implantation
â˘Candidacy coordinated by audiologist
â˘Requires specific expertise
â˘Rapidly evolving field
â˘Much success in very young (< 18 months)
children
â˘Ongoing technological advances and
opportunities
69. Communication methods in the education of deaf children
1.Auralism: use only speech and lipreading as a means of
communication
â˘Signing- strongly discouraged or prevented
â˘Oralsits-ability to develop speech inhibited by allowing signing
2.Finger spelling:
3.Cued speech:
â˘M,P,B or K,D,L â not distinguished by lipreading alone
â˘Different hand shapes in different positions close to the speakerâs
mouth to enable the child to discriminate the lip movement
70.
71. 4.Signing system (manualism):
British sign language, American sign language
5.Total communication:
Uses any and all modes of communication (combination of speech,
gestures, signing, finger spelling, speech reading/lip reading, reading
and writing)
Controversy:
â˘Sensory inputs (auditory & visual)ď enhances language development
â˘Total communicationď impair speech developement
72. The Deaf Community
ďSupportive, strong community
Does not view hearing loss as a
disability
ďRich history and language
(e.g., American Sign Language)
ďChildren with cochlear implants may
have limited access to the deaf community
74. Assistive Devices
ďObtain devices - doorbells, timers, alarm clocks and fire alarms
ďAlerting devices
hearing dog
alarm clock with flashing light
devices producing strong vibration
ďTelecommunication devices
Telephone amplifier
Telephone coupler attached to hearing aid
Telecommunication devices for deaf (TDD)
ďTeletypewriters (TTYs) machines - enable deaf people
to use the phone
75. Follow-up
ď Deaf childď Follow up
ďAudiologist:
- Monitor progression
- Hearing loss
- Refit hearing aids - match changing losses/ growth of ears
ďPediatricians:
Monitor linguistic/ social development
ďChildren who are deaf or hard of hearing are at particular risk
for abuse