Transcript Visual Impairment - LSU Human Development Center

USHER SYNDROME:
What we need to know
Annette Hurley, PhD
LSU Health Sciences Center
Audience?
What is Usher Syndrome?
• A syndrome which affects both hearing and vision. It is
an inherited condition; both parents must be carriers
• About 3-6 percent of all deaf children and perhaps
an equal number of hard-of-hearing children have
Usher syndrome (Boughman, Vernon, Shaver, 1983).
• Other researchers believe the prevalence of Usher is
closer to 17% (ASHA, 2009).
• At present there is no treatment for this condition.
Types of Usher
Syndrome
Type 1 (USH1)
• Marked by profound deafness at birth and severe
balance problems.
• Many will not benefit from hearing aids
• May use sign language to communicate.
• May be implanted at an early age.
• These children begin to develop vision problems by
the time they are 10 and usually start with difficulty
seeing at night; this progresses rapidly until
blindness eventually occurs.
Type 2 (USH2)
• Marked by moderate to severe hearing loss at birth
but no balance problems.
• Most of these children benefit from hearing aids and
will use speech to communicate.
• The visual problems tend to progress more slowly
than in USH1 and are characterised by blind spots
that begin to appear during the teenage years.
Gradually, the vision deteriorates to blindness.
Type 3 (USH3)
• These children have normal hearing and near
normal balance.
• They usually develop hearing problems during
their teenage years and become deaf by mid to
late adulthood.
• Night blindness usually starts during puberty,
blind spots appear in early adulthood and the
individual is usually blind by mid adulthood.
• (Least represented in the US- more common in
Finland.)
Hearing Loss
• 95% of infants in the US are evaluated prior to discharge by
early hearing detection and intervention programs. (NCHAM)
lowering the age of identification of hearing loss.
• Dx of Usher syndrome, typically lags 5-10 years behind the
identification of the hearing loss (Kimberling & Lindenmuth,
2007). Early diagnosis might affect management.
• Genetics:
• Connexin 26 responsible for 50% of non-syndromic hearing
losses.
• Cost?
• Affect Management
Genetics
• If a child has Usher, both parents must carry the recessive
gene.
• The child will not be affected with the disease unless both
parents are carriers.
Dual Sensory Impairment
• Dual sensory loss, or a combined vision and hearing deficit are
increasing as the number of seniors grows over the next
several decades.
• It is estimated that 9-21% of people 70 years and older have
dual sensory loss. (Atorowitz, Brennan & Su, 2001).
• Increase in TBI in Vets.
• The brain has 2 major pathways for processing information,
the visual and the auditory cortex.
Auditory and Visual Pathway
• The connections between the brain’s auditory and visual regions
are carried by neurons that integrate the two senses together.
• Listening to sound activates visual cortex. Seeing a person’s lips
move helps with actually hearing speech.
• We also need to orient our visual and auditory attention to the
same events and to the same place in space.
• Both of these key senses are critical to daily life, and while the
loss of either can be debilitating the loss of both affects every
moment of every day.
• Speed of moving objects
• Mismatch Scenes.
Auditory System
• Develops in first 20 weeks of gestation
• Early onset auditory deprivation can have a profound effect on
development.
• Brain changes without stimulation
• Pre/Post lingual
• Hearing Age? Vs Chronological Age
Types of Hearing Loss
• Conductive (Disorder in Outer or Middle ear-otitis media,
otosclerosis)
• Sensorineural (Disorder in the
Inner ear, Syndromes,
presbycusis,etc)
• Mixed- (Combination of Conductive & Sensorineural
Components)
Audiogram-a graph of a person’s hearing
thresholds
Audiograms…
What does a hearing loss sound
like
• Profound
• Moderate
• Normal
When did the hearing loss occur?
• Pre-lingual (95%)
• Post-lingual (i.e. Progressive Hearing Loss)
Prevalence of Hearing Loss
• 28 million Americans in the U.S. have a hearing loss.
• 27,000 individuals in the US have Usher (PPNET).
• Children under 18 years of age have the
lowest prevalence, but greatest
educational impact!
How Many Children Are
Affected?
• Over 1 million children in the United States have a hearing
loss.
• For every 1000 children in this country, 83 have an
educationally significant hearing impairment.
• Approximately 3-6% of deaf children have
Usher Syndrome. Other researchers
believe 17% of Deaf individuals.
Treatment for Usher Syndrome
• Currently no medical treatment to prevent, slow
the progression, or inhibit the transmission of
Usher syndrome.
Cochlear Implants
• A surgically implanted device that brings sound to the inner
ear. This is used only for persons with profound hearing
impairment.
Hearing Aids
• Small instruments that amplify sounds to bring sound into the
normal range.
Assistive Devices
FM systems
• System which brings a signal such as the teacher’s voice
directly to the student by means of frequency modulated
radio waves.
• Improves the signal to noise ratio
Deaf Culture
American Sign Language
• “Deaf” is a term used to describe a person who belongs
to the “Deaf” community. They usually attend Deaf
schools and use American Sign Language (ASL) for
communication purposes.
• 90% of children who are deaf have hearing parents.
• Adaptive “Hands-On” Signing and Finger Spelling.
After Amplification
-Early amplification is critical for success.
• Most kids have some residual hearing
• Children with severe and profound hearing loss present a
range of listening skills
• Early and appropriate amplification is critical for normal
speech and language development.
Deafness and Intelligence
• Same distribution of intelligence
• There is potential for abstract thought among deaf & hard of
hearing
• Educational achievement level of deaf is low
• Deaf children of deaf parents score higher on performance IQ
tests than deaf children of hearing parents.
Other Disabilities
• 30% of hearing impaired children have a disability in addition
to hearing loss.
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Intellectual deficits
Learning Disabilities
Attention Deficit
Visual Impairment
Cerebral Palsy
Orthopedic Problems
Individual
• “No two blind people are alike….no two d(D)eaf people are
alike.
• Refer for counselling, other support
• We cannot assume all professionals are familiar with impact of
dual sensory loss.