Lecture 2.2 Flashcards
How was hearing loss identified in the early days of audiology?
100 dB signal played directly into the babies ear at the newborn phase
determines if the baby responded at all to see if they can hear
- only really ruling out profound deafness - signal is so loud
What recommendations emerged from 1967 National Conference on Education of the Deaf?
children with higher likelihood of developing hearing loss are tested
- high risk register to facilitate identification
testing of infants and children 5-12 months should be investigated
What did White 2010 studies show about screening based on high risk register?
if you only screen children with a risk factor, only going to catch 50% of children
other 50% don’t have a risk factor
need to screen early and universally
How has the view on deafness changed over the years?
16th century - recognized deafness was a barrier to communication not an intellectual deficit
late 19th century - deafness viewed as a problem belonging to the field of education
1960s - acknowledge significant delays if hearing loss not identified early
- screened high risk infants first
What is JCIH?
joint committee on infant hearing
formed in early 1970s
addresses populations to be screened, methods and protocols to be used for screening, and later guidelines for early ID and intervention
What are soundfield systems? How were they used?
speaker systems set up in classroom, connected to microphone for speaker
early versions used in educational settings
later determined children with hearing loss benefit from sound access throughout the day
- children later able to wear binaural hearing aids on the body using a harness
What developments in prescriptive formulae occurred in the 1980s?
appropriate hearing aid gain, output, and frequency response was studied extensively
prove mic systems became available
CIs approved for use with children
What is gain?
prescribed amount of volume provided by hearing aid based on hearing thresholds and ear canal volume
we adjust to meet targets
in dB SPL
What is the goal of rehabilitative and educational management of children with hearing loss?
overcome or minimize the barriers to communication imposed by hearing loss in order to enable learning and participation to society
What 2 categories did children with hearing loss historically fall into?
those who had considerable access to acoustic speech signals
those who had limited or no access to speech despite the best technology
What 2 parallel rehabilitaiton and educational management philosophies evolved?
manual approach - visual-based system, natural for those who are deaf (those who can’t or chose not to access speech through technology)
oral approach - spoken communication
What was the average age of hearing loss identification before the infant hearing program? What are the impacts of this?
2.5 years
late identification = window to access/learn speech, language, and literacy closes, impairs social and cognitive development
What factors result in good language outcomes?
good hearing aid fittings
consistent hearing aid uses
language input (quality and quantity)
What is UNHS?
population screening of all babies, regardless of the presence/absence of risk, for the possibility of hearing loss
component of EHDI programs
What are EHDI programs?
Early hearing detection and intervention
comprehensive public health program including UNHS, audiology assessment, hearing loss management, family support, language development support, and monitoring of infants and outcomes
go beyond population screening and offer services to confirm presence of hearing loss and provide intervention services
What is the importance of early detection and intervention?
saves society money on more intense remediation
supports language development, child development, psychosocial well-being, behaviour, and academic success
What is the prevalence of children born with hearing loss?
1-3 / 1000 births
progressive and late onset losses underestimated
What is screening?
a strategy used to identify the possible presence of a yet undiagnosed condition in a population without signs or symptoms
not diagnostic or therapeutic - no resources for follow up
What is assessment?
evaluation of health status to detect disease or condition
What is intervention?
the act of intervening with the intent of modifying outcome
technology and/or language services
What is the definition of deaf?
condition where a person has little or no hearing in both ears
also used to describe a person with this condition whose preferred mode of communication is spoken language
the audiological term - but usually profound bilateral hearing loss used
What is the definition of Deaf?
members of a sociolinguistic and cultural group whose preferred method of communication is sign language
involvement in Deaf community is distinctive feature
- don’t need to have hearing loss (ex. spouse who uses signs to partner)
What is the definition of hard of hearing?
permanent partial or total inability to hear in one or both ears
this term is used to describe a person who has the condition and whose usual method of communication is spoken language
What is the definition of permanent hearing loss?
hearing loss of a particular degree (target level) in any ear caused by disorders of the cochlea, brainstem auditory pathways, or structural abnormalities affecting sound conduction through the external or middle ear structures
hearing loss is permanent if it will not resolve spontaneously and will present a loss of hearing sensitivity in the absence of intervention
What is the importance of EHDI programs?
critical in lives of Deaf/deaf or hard of hearing children to ensure optimized language, literacy, and social skill development
What are the 5 components of EHDI programs?
universal screening
identification of babies with permanent hearing loss
- using evidence based diagnostic techniques
provision of evidence-based intervention services
- including support for technology and communication development
provision of family support
monitoring and measuring
- impact of interventions and program
What are the updated EDHI recommendations?
1-3-6 rule
all infants should undergo hearing screening by 1 month
all infants who fail screening will have a complete audiological assessment by 3 months
early intervention services should begin as soon as possible after diagnosis, no later than 6 months
regions that meet 1-3-6 should strive for 1-2-3
What did the CIHTF report card on EDHI programs find?
BC = excellent (only province)
Ontario = good
Canada overall grade = insufficient
- some of EHDI components missing or not implemented in certain provinces
What is the Ontario IHP?
infant hearing program
identifies children born Dd/HH through UNHS or audiological assessment
provides support and services for children birth-grade 1 who are identified with permanent hearing loss and their families
What is the target population of the IHP?
infants with permanent hearing loss
- sensorineural greater than 25 dB HL
- auditory neuropathy spectrum disorder
- conductive losses lasting 6+ months
children under 6 with PHL
- have to pay to see audiologist in the community after age 6
What populations are NOT targeted by IHP?
children of any age transient hearing disorders due to middle ear fluid and/or infection
- such disorders (when cochlea functioning normally) are the domain of OHIP or fee for service audiology clinics
NOT an alternate system for audiometric services in active medical/surgical management of conductive hearing disorders
What are the outcomes of the IHP?
in each year since implementation, IHP has screened 95-97% of Ontario babies
- exceeds 90% target
each year screens over 132,000 infants and identifies ~450 infants with PHL
- over 2 million newborns screened since its creation
What are the components of the Ontario IHP?
UNHS
- for Ontario-resident infants 2 months of age of younger
audiological surveillance
- for all infants with risk indicator known to cause late onset/progressive PHL
hearing assessment
- to confirm presence of PHL and provide referrals
intervention/support
- for infant/family if PHL confirmed
evaluation of need for assistive technology
Who are the service providers within the IHP?
all are trained in IHP protocols/have experience with patients with PHL
UNHS often provided by nurses or CDAs
audiologists provide assessment and amplification services
social workers provide family support
SLPs or ASL consultants provide language development services
How is the IHP delivered?
regional lead agencies across the province deliver the program in accordance to guidelines
- deliver some or all IHP services in local areas
lead agencies include hospitals, public health units, Children’s treatment centres
complex, comprehensive service delivery pathway
What components are in place to ensure consistency of EHDI components in Ontario?
evidence-based, mandatory protocols
uniform equipment
mandatory standardized training for service providers
outcome measurement
What is the UNHS protocol?
complex, comprehensive series of steps based on results of screening
all benchmarks to be completed by 1 year
What is the IHP hearing screener’s role?
explain screening
obtain consent/documentation
assess for risk factors
conduct hearing screening
explain results
provide next steps
What is a risk indicator?
identifiable characteristic of a child or medical procedure that is associated with increased likelihood of PHL in the child
identified by IHP screener through document review, consulting medical staff, and talking to family
What is the purpose of the risk fator assessment?
determine whether screening should be bypassed
decide what type of screening test to use
record information that will determine whether infant should receive later testing (surveillance) and if so what type of surveillance
How are risk factors grouped?
into 3 categories that determine next steps
no surveillance, surveillance, intensive surveillance/further referral
What test is used for the UNHS?
ADPOAE (automated distortion product otoacoustic emission) and/or AABR (automated auditory brainstem response)
identifies need for further hearing assessment by IHP audiologist
What infants are identified as being at risk?
those with one of the pre-defined risk factors for PHL
these babies will instead be screened using AABR (PHL risk is already 10x higher and ADPOAE will not detect specific risk factors)
How are at risk babies grouped?
at risk babies (group 1 and 2 risk factors) will be screened using AABR
babies with group 3 risk factors will bypass screening and go directly to audiological assessment
group 1 - AABR screen, discharge if pass
group 2 - AABR screen, surveillance if pass
group 3 - do not screen, directly to audiology
What are group 3 risk factors that would cause babies to bypass screening and go directly to audiology assessment?
atresia/microtia
meningitis
cCMV
positive genetic screen
Why is the way the hearing screener communicates with families important?
accurate and consistent info helps establish families’ trust in IHP services
sets stage for family’s first impression of IHP program, effectiveness of program, confidence in abilities of screener, willingness to follow recommendations
What are standardized scripts?
used by hearing screeners in Ontario
standardize the way information is provided throughout the program
reduce family anxiety, facilitate families proceeding with follow-up, supports delivery of high quality information
What are possible next steps after screening?
discharge
community screen
audiology high risk surveillance
audiology assessment
What is the dried blood spot screening?
IHP in collaboration with newborn screening Ontario (NSO) determined it was possible to detect certain causes of PHL that might not otherwise be identified through dried blood spot screening
infant heel prick
targeted conditions chosen due to prevalence and ability to be detected by existing blood spot screening
only one in the world!
improves effectiveness of risk assessment process, allow for earlier and more accurate identification of risk factors
What is cCMV?
herpes family virus causing mild or asymptomatic infection in healthy individuals
potential for serious infection in fetuses or immunocompromised hosts
leading cause of non-genetic sensorineural hearing loss
second leading cause of intellectual disability after Down syndrome
What is the positive predictive value of cCMV bloodspot screen?
very high - >98% - reported as “detected’
with high viral load of cCMV, babies’ risk of developing hearing loss is 1/3 if symptomatic and 1/10 if asymptomatic
What is the positive predictive value of genetic mutation?
very high - >98%
nearly assured to have it if screened possible
What is positive predictive value?
how likely is it the baby really has that condition when test comes back positive
What is negative predictive value?
if the test is negative, how likely it is that the baby really does not have that condition
What is the negative predictive value of genetic mutation?
very high
if screen negative, very unlikely to have these mutations
What is the care pathway if screened cCMV positive?
retrieval managed by NP
refer to community paediatrician for initial evaluation
infectious disease referral for symptomatic infants
referral for ABR assessment ASAP
What is the care pathway if genetic screen is positive?
retrieval managed by genetic counsellor/audiology team
ABR assessment by audiology
refer to ENT and genetics
What is audiological surveillance?
proactive recall for audiological appointment of children at risk of developing late onset or progressive hearing loss
symptomatic process for early detection of PHL not detected by UNHS
basic = single point
intensive = multi-point
What is the purpose of audiological assessment?
determine presence of PHL
estimate hearing levels in each ear at several frequencies
determine type and configuration of PHL for prompt and accurate hearing aid fitting
How is audiological evaluation completed between 0-6 months?
estimates of hearing sensitivity derived from ABR measurements
hearing aid selection and fitting done using ABR threshold estimates
done in sleeping babies
What is the role of the family support worker?
share information with audiologist
help with financial applications
support chosen language development pathway
facilitate parent-to-parent connections
How does language development begin in infants with PHL?
families supported in choosing a language development path
- sign (ASL consultant) or spoken (SLP)
aim for services to start no later than 6 months, as close to home as possible
What are the 3 main factors influencing outcomes in children with hearing loss?
consistent hearing aid use
- at least 10 hours/day
audibility
- how well sound is heard
- controlled by audiologist
linguistic input
- quality and quantity
