Ushers syndrome

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Usher syndrome
Working with families in the Early Years
Wendy Pallant
Teacher of the MultiSensory Impaired and Teacher of the Deaf
wendy@pallant.info
www.schooltrain.info
About Me
Qualified as a Teacher of the Deaf in 1987
•Class Teacher in School for the Deaf in
Hertfordshire
•Advisory teacher in Northamptonshire
(Signing provision)
•Deputy Head in School for the Deaf in
Lancashire
•Advisory teacher in Lancashire (Early
Years)
Working with MSI since 2004. Qualified as a
Teacher of MultiSensory Impaired in 2008
MultiSensory Impaired/Deafblind
Department of Education (DES) Policy Statement
"Educational Provision for Deafblind Children“ (1989)
A continuum of loss
•varying degrees of visual and hearing impairment
•perhaps combined with learning difficulties and physical
disabilities
Department of Health
Persons are regarded as deafblind/MSI if their combined sight and
hearing impairment cause difficulties with
• communication
• access to information
• mobility
Who is MSI
…..any degree of dual-sensory
impairment that has a significantly
adverse effect on the child’s ability
to access education.
The children in this group will have
very different needs arising from a
congenital loss, acquired loss or
degenerative condition. (p5)
Download from:
http://www.sense.org.uk/OneStopCMS/Core/Cra
wlerResourceServer.aspx?resource=2C50A00D845A4CECA5D128C72ECA2DC4&mode=link&g
uid=f63692af3f734c478df94b1d850903df
QTMSI Input
may include children from the following groups:
• Children who present as having hearing and vision loss both of a level that
would, if as a single sensory need (HI/VI), lead to at least a moderate level
of input from a sensory specialist teacher (QTVI/ToD). …..
• Children whose diagnosis is not yet confirmed or completed but for whom
the diagnostic process will be enhanced & expedited by input from a
QTMSI…. This may include children with a progressive syndrome where
dual sensory loss is likely in the future
• Children who have profound and complex learning needs where functional
use of distance senses of vision and hearing require specialist input to
support development.
Role of QTMSI
Specialist support may be provided at home and in childcare and early
education settings
• diagnostic and educational assessment
• facilitate individual access to information for learning
• support suitable methods of communication
Diagnosis
“Most of us find out that our child is not destined to be Mozart
when he or she begins to slaughter the clarinet in fifth grade band.
But by then he or she has demonstrated other strengths.” Mark Dunning
“But for a parent of a newborn
child identified through the
newborn hearing screen, that
reality slams home at an
unwelcomed time and at an
unwelcomed pace.” Mark Dunning
Involvement of Teacher of the Deaf
Supporting parents
Identification of hearing
loss
•
What can my child hear?
•
How will I be able to communicate
with my child?
•
Will my child speak?
•
Will my child sign?
•
Where will my child go to school?
Why is my
child deaf?
Levels of Hearing Loss
Speech banana
Moderate (41-70dB)
Normal Hearing
Severe (71-95dB)
Mild (20-40dB)
Profound (95+dB)
Vision and Deafness
Quality standard 10
Following the diagnosis of permanent
conductive or sensorineural deafness, or if a
child needs hearing aids, the child should be
referred for a full ophthalmic assessment, and
this should be repeated where appropriate at
key stages of their development.
Quality standard 13
Ideally a follow-up appointment within two weeks
should be offered for children who are priorities
... The family may want to involve their key
worker in appointments. The family should be
provided with contact details for the vision team
or the local authority visual impairment teaching
service.
Childhood deafness
NDCS Genetic Counselling p11
Claes Moller
80-100 different syndromes
Often presents as non-syndromic
Syndromic and Genetic Deafness
Waardenburg
syndrome
Usher syndrome
Too small
Treacher syndrome
Dow n syndrome
CHARGE sydnrome
Chromosome
abnormality
Connexin-26
Other
Gallaudet University: 2004-5 (Number of children 3143)
Incidence of Usher Syndrome
Claes Moller (2009)
10% of children referred for Cochlear Implant
Usher Type I
Usher Type II
Usher Type III
 Profound deafness
in both ears from
birth
 Moderate to severe
hearing loss from birth
 Stable loss
 the rate at which they decline can
vary from person to person, even
within the same family.
 progressive hearing loss
may start as mild loss
Similar to Type 1 by 40-49
usually require hearing aids by midto late adulthood.
 tend to progress more
slowly than those in type
1
 onset of RP often not
apparent until the teens.
Vision
 usually begin to
develop vision
problems in early
childhood
 almost always by
the time they reach
age 10.
 vision problems
most often begin
with difficulty seeing
at night
 the rate at which they decline can
vary from person to person, even
within the same family.
 night blindness usually begins
sometime during puberty.
 blind spots appear by the late teens
to early adulthood
 usually legally blind by mid
adulthood.
 normal
Vestibular
function
(balance)
 slow to sit without
support
 typically don’t walk
independently before
they are 18 months
old.
normal to near-normal, chance of
later problems
Looking at hearing loss
alone can’t tell if type 2
or 3
Like type 2 in childhood and type 1 in
later adulthood
Hearing
http://www.nidcd.nih.gov/health/hearing/usher.asp and Claes Moller
Acquired Deafblindness
Acquired Deafblindness (Claes Moller)
• 80-90% of all causes are genetic
• About 30 known Syndromes
• Most have congenital deafness and progressive vision
loss
• Usher Syndrome – accounts for nearly 50% of cases
with Deafblindness
• 8-10/100,000 newborns although recent research
indicates that it could be as high as 15-21%.
Identification and Diagnosis
Claes Moller
This is the population in a Swedish Study. This graphs shows the high
incidence of late diagnosis.
Early Diagnosis?
The median age of identification of congenital
deafness will be lowered by Newborn Hearing
Screening from 20 months to 3 months.
“At what stage should a deaf child be tested for a
condition such as Usher syndrome for which there is
no cure and which is likely to lead to a progressive
loss of vision? What use is there in parents knowing
that their two year old child is likely to begin to lose
their vision in maybe five or even ten years’ time?
Does it really help parents to make a decision
whether or not to go ahead with a cochlear implant?”
Fiona Pearl
Who should know when?
“I think I would have preferred to have
avoided the huge stress, depression and
helplessness brought about by the
diagnosis of my two year old son as
having "retinal dystrophy most likely to be
associated with Usher syndrome". This
was as a result of the routine tests
performed as part of his assessment for a
cochlear implant.” Fiona Pearl
Usher Syndrome
Identification of hearing
loss
•
Will I be able to communicate with
my child?
•
Will my child speak?
•
Will my child sign?
•
Where will my child go to school?
• Other children are sitting/walking.
• Why isn’t my child?
• What is wrong?
• Will he or she ever walk?
Why is my
child deaf?
Early Diagnosis?
• Can remove the concern about walking.
• Your child may walk late, but they will walk…..
• … because they eventually develop the muscle strength to offset the
lack of vestibular function.
Physical activities can help children with vestibular abnormalities
develop the strength and flexibility to participate in just about any activity.
Children are most successful when they develop muscle strength at a
young age.
Parents should be aware of the safety risks associated with vestibular
difficulties so they can compensate appropriately.
Mark Dunning
Understanding Balance
• Stand, feet together, arms folded into body
• Now close your eyes.
• What did you notice?
• Moving slightly to make postural
adjustments
• Repeat but with legs apart.
• What did you notice?
• Adopting a wider base makes it easier to
balance
Vestibular Organs
The inner ear contains two separate organ systems encased within a bony
capsule
• the cochlea for hearing
• the vestibular organs for balance - semicircular canals , the utricle, and
the saccule.
The Semicircular Canals
There are 3 semicircular canals
in each ear.
Each canal works with a partner
on the other side of the head.
The canals contain sensory hair
cells that are activated by
movement of inner ear fluid
(endolymph).
One pair of canals is horizontal. The other two pairs are almost vertical at right
angles to each other.
This means each of the 6 canals is best activated by a different direction of head
rotation.
The Utricle and Saccule
The ends of the semicircular canals
connect with the utricle.
The utricle connects with the saccule.
The sensory hair cells of the utricle and
saccule provide information to the brain
•
about the direction of movement (linear
acceleration)
•
the head’s position in relation to gravity
(which way is up).
The Balance System
The hair cells for both
movement and static position
create nerve impulses.
These impulses travel via the
vestibular nerve to the
brainstem, cerebellum and
spinal cord.
This information triggers many reflexes including motor impulses to make
postural adjustments.
Balance and Usher
Young children take longer to
reach developmental
milestones such as sitting
unsupported and walking.
Children with Usher Type 1 don’t walk before 18 months.
Vestibular Ocular Reflex (VOR)
• Another key reflex is the vestibular ocular
reflex (VOR).
• This reflex stabilizes the retinal image
during rotations of the head.
Activity
Vision and balance
• Stand, feet together, arms folded into body.
• Challenge your balance - lift one leg. How many
seconds can you maintain balance for?
• Now close your eyes. How many seconds can
you maintain balance for?
• Try counting in 13s while standing on one leg.
We need postural security to think and learn.
Equilibrial triad
The vestibular system
provides your brain with
information about how you are
moving your head
Vision
gives the brain information
on how we are upright in
the environment
Triad of Equilibrium
Proprioception
muscle stretch, joint
position, tendon
tension
tells the brain
(cerebellum)
information on where
our body is in
relationship to the
environment.
The balance system
A properly functioning balance system allows people
• identify orientation with respect to gravity
• determine direction and speed of movement
• make automatic postural adjustments to maintain posture and stability
• to see clearly while moving
Young children with balance difficulties
Vision and vestibular function
help you interpret the right
position to hold your body for
the best balance.
If you lean forward or to the side
you will eventually fall over.
Gymnasts can hold themselves
in gravity defying positions
because of their strength and
flexibility.
Mark Dunning
If a child is born with or acquires a
balance problem early in life it is
likely that they will develop ways
of compensating.
Usher Syndrome
Identification of hearing
loss
•
Will I be able to communicate with
my child?
•
Will my child speak?
•
Will my child sign?
•
Where will my child go to school?
Why is my
child deaf?
Diagnosis of Usher
Syndrome
• Other children are walking.
•
Will my child lose his or her vision?
• Why isn’t my child?
•
What will happen to my child?
• What is wrong?
• Will he or she ever walk?
Understanding Vision
Visual acuity
Colour vision
Visual field
Binocular vision
Adaptation and night vision
Page 5
Understanding Vision
Page 5
The Eye
The retina at the back of the eye is a light-sensitive layer which
consists of rod and cone cells. These cells collect the light
signals directed onto them and send them as electrical signals
to the optic nerve at the back of our eye.
Rod Cells
• responsible for peripheral vision and the absorption of light during
darkened conditions
• concentrated around the edge of the retina.
• help us to see things that aren't directly in front of us, giving us a
rough idea of what is around us.
• help us with our mobility and getting around by stopping us from
bumping into a things.
• also enable us to see things in dim light and to see movement.
Rods are good at seeing:
– things that move (not directly in front of us)
– in the dark
– but only in black and white
– and in less detail.
Cone Cells
• control central vision and differentiation between colours
• are concentrated in the centre of our retina where the light is
focused by the cornea and lens. This area is called the macula.
• give us our detailed vision which we use when reading, watching TV,
sewing and looking at people's faces.
Cones are good at seeing:
- things that are still
- in daylight
- in colour
- fine detail
Electrophysiological Tests
• The challenge of testing a young infant's vision is that
they cannot verbally communicate what they can and
cannot see.
• Electrophysiological testing is most helpful for testing
youngsters for whom other vision tests give ambiguous
or incomplete information about visual acuity.
• The VEP and ERG provide information about what is
happening at the physiological level and are thus
especially important in the diagnosis of visual
impairments in very young children.
Visual Evoked Potential (VEP)
Visual acuity = the ability to see fine detail and patterns
A ‘visual evoked response’ (VER) or ‘visual potential test’ is a record of
the electrical activity in the brain as a response to stimulation of the
retina.
These signals are recorded with electrodes lightly attached to the scalp
at the back of the head while the child watches patterns on a computer
screen.
measures the response of the brain to
alternating black and white stripes or checks.
designed to find the finest black and white
stripes that reliably produce a response
Multifocal ERG (mfERG)
A new type of electroretinogram,
called the multifocal ERG
(mfERG), allows responses to
be simultaneously recorded
from multiple retinal areas
using a stimulus array made
up of black and white,
flickering hexagons (a).
The results can be analyzed to
provide a contour map (b) of
the function of the center of the
retina, called the macula. This
is the specialized part of the
eye that is used to read letters.
It is also the last part of the
retina to develop.
The child is positioned on the
doctor's lap in front of a video
monitor. The contact lens picks up
electrical signals produced by the
retina, following which a map of the
functional integrity of the retina is
plotted.
Electroretinogram (ERG)
evaluates the function of the retina
During the ERG test, the cells of the retina (rods and cones) release
tiny amounts of electricity in response to flashes of light.
If we know exactly how much light enters the eye and how much
electricity comes out, we can figure out how the rods and cones are
working.
To pick up the electricity from the retina, a special contact lens is
placed on the surface of the eye after eye drops have dilated pupils.
An ERG is one of the tests used to test for ‘Usher syndrome’.
Testing Visual Acuity
Depending on the individual development of the child, these tests
use cards with stripes, pictures, letters or numbers on them.
Distance Vision (without correction)
Glasses prescriptions for myopia (short sighted) have a minus number.
Refractive Errors
Usually correctable with glasses
or contact lenses.
Page 12
Visual Acuity (Distance Vision)
Partially sighted / Sight impaired
Visual acuity of 3/60 to 6/60 with
full field of vision
Visual acuity of up to 6/24 with a
moderate reduction of field of
vision or with a central part of
vision that is cloudy or blurry
Visual acuity of up to 6/18 if a
large part of your field of vision (eg
half) is missing or a lot of your
peripheral vision is missing
Blind / Severely sight
impaired
Visual acuity of less than
3/60 + full visual field
Visual acuity
between3/60 and 6/60 +
severe reduction of field
of vision (tunnel vision)
Visual acuity of 6/60 or
above + with very reduced
field of vision, especially if a
lot of sight is missing in the
lower part of the field.
Visual field
The normal human
visual field extends
• 60 degrees nasally
(toward the nose, or
inward)
• 100 degrees
temporally (away
from the nose, or
outwards)
• 60 degrees above
• 75 below the
horizontal meridian.
How is the visual field tested?
Young children: With the child’s attention drawn to the front, have another
person stand behind the child and slowly bring a toy on a stick (or something
similar) into the right, left, top and bottom areas of the visual field. Observe
and note the points at which the child becomes aware of the stimulus.
Older children: Both eyes look
directly at a small spot in the
centre of the perimeter while an
object is presented to the
periphery. The person indicates
when the object is detected. The
person's field is plotted on a sheet
of paper. Testing with objects (or
lights) of different size (or
brightness) results in visual fields
of different sizes.
The visual field is measured
using a "perimeter".
Retinosa Pigmentosa
There a many varieties of RP, each with its own
time of onset, degree of severity and set of
symptoms.
The overall uniting characteristic is the decay of
photoreceptor cells, which are found in the retina
and include two types – rods and cones.
Whereas these cells die off naturally in all
people, those with RP do not generate new rods
and cones as would a healthy retina. The result
is a slow decay of vision.
Symptoms of Retinosa Pigmentosa
The optic nerve (arrow)
looks very pale, the vessels
(stars) are very thin and
there is characteristic
pigment.
Pigmentation starts in
periphery and gets
closer towards the central
vision.
•
•
•
•
www.nidcd.nih.gov/health/hearing/usher.asp
Decreased night vision
Light sensitivity
Bad adaptation when moving from bright to dark
Visual field loss (tunnel vision/blind spots)
Usher Diagnosis
blind
Blind doesn’t usually mean
no vision.
Most people with Usher
Syndrome will have some
residual vision will into
adulthood
Simulation of vision at 30-40 years
Genetic Testing
Recessive Genes
Recessive means:
• a person must inherit a change in the same gene from each parent in order
to have the disorder
• a person with one changed gene does not have the disorder, but can pass
either the changed or the unchanged gene on to his or her child
With each birth there is
• 1-in-4 chance of having a child with Usher
syndrome
• 2-in-4 chance of having a child who is a
carrier
• 1-in-4 chance of having a child who neither
has Usher syndrome nor is a carrier
Genes in Usher
Usher
Type 1
Usher
Type 2
These can be tested.
Functional Sensory Assessment
1. Hearing
Distance senses
External senses
2. Vision
3. Smell
4. Touch
Near senses
5. Taste
6. Vestibular (the sense of movement)
Internal senses
7. Proprioceptive (the sense of body position)
Compensatory Strategies
Functional Sensory Assessment
• What sensory
information do I
respond to?
Distance
Close
Vision
Hearing
Smell
Touch
Movement
- vestibular
- proprioception
Taste
• What are my stronger sensory channels?
• Do I respond more easily if sensory channels
are combined?
• What affects my ability to use my senses?
Nightblindness/Adaptation difficulties
Observe how the child reacts in varied and unfamiliar environments
1.
When moving from a bright to a darker area
2.
When moving from a dark to a bright environment
3.
In different lighting conditions
What to look for
•
The child is clumsy, especially in low light
•
Unhappy in low light
•
Loses balance easily in the dark
•
Wants to hold your hand at dusk but not at other times
•
Changes from visual to tactual behaviour
•
Hesitates or becomes distressed
•
Anxious at night time
•
Can't see when coming in from bright sunlight
•
Trips over things when light changes or light is dim
•
Seems to have more difficulty locating and recognising things
Nightblindness/Adaptation difficulties
• Stays near a light in a dark room or at night
• Moves a speaker so light falls on face
• May express a desire to enter a room before it is darkened (movie
theater, etc.)
• Avoids conversations in a darkened area
• When walking along a road at night, may appear to stagger or lose
balance after an oncoming car has passed
• Has problems reading under some lights or in dimly lit areas
• Squints and shades eyes in bright lights or fluorescent lighting complains that the light hurts his/her eyes
• Likes to wear sunglasses even in buildings, but especially in bright
sunlight
• Avoids going outside when the sun is very bright
• May appear awkward when exiting from the inside to the outside of
a building (when faced with bright light)
http://www.tsbvi.edu/Outreach/deafblind/usher.htm
Catherine Southwell
Visual field
Observe how the child reacts in varied and unfamiliar environments
1.
Unexpected changes of surface level or shade – for example, a
step, or a change from hard floor to carpet?
2.
Response to objects and people
•
•
Does the child ever fail to notice objects (on left, right, waist, above
eye level)?
Does the child often bump into, or trip over things?
What to look for
•
•
•
•
•
•
•
•
•
•
•
•
•
Anxious in narrow places
Tends to bump into door frames, people, tables, and chairs
Stumbles on stairs and curbs
Hesitates at the top or bottom of stairs
Trips over frequently
Startles easily
May appear to ignore others standing by his/ her side
Seems to hold eyes in a different direction when looking at some things
(because of islands of vision)
Turns head a lot when looking
Uses finger to mark place while reading
Can't find small objects that have been dropped
Fails to glance at another person's hand waving from the side
Exhibits symptoms of anxiousness in new areas
Balance: What can we do?
Good balance is
supported by having
strong back and tummy
muscles. Infants and
children need constant
activity to develop these
areas.
Control lighting: fit blinds
and dimmer switches,
use night lights or lamps
in hallways at night eg
toilet training.
Stop to look.
Carry an LED torch.
Talk to parents about the
risks of over-protection.
Supervise closely when
swimming in case they
become disorientated
underwater
Night blindness/adaption: What can we do?
• Good lighting without glare
• Use night lights plugged into sockets to act as landmarks in dark
areas or at night time in the bedroom
• Use table lamps (with shades) in dark corners and to emphasis
pieces of furniture that stick out into a room
• Carry an LED torch
• Prescription glasses with tinted photosensitive lenses
• Wear a hat with a large brim
Night blindness/adaption: What can we do?
• Give a running commentary on routes including landmarks –
encourage child to remember the sequence. Use language to
describe positions, directions, textures and distance
• Talk explicitly about safety – she may not pick things up incidentally
like other deaf children eg turning saucepans away, holding and
passing scissors safely.
• Teach the child to be orderly
• Promote manual dexterity
• Teach touch typing
• Teach the child the language to explain needs to adults and friends.
Encourage to accept and ask for help.
Certificate of Visual Impairment
www.rcophth.ac.uk/standards/cvi
• After assessment of your eye condition, the hospital consultant
completes the CVI – certificate of visual impairment, which certifies
that you are eligible to be registered by your local Social Care
Services department as either blind or partially sighted.
• Normally the consultant keeps one copy, you receive another and
copies are sent, with your consent, to the Social Care Services
department, your GP and the Census. This information is
confidential and is not passed on to anyone without your permission.
• Social Care Services departments have a statutory responsibility to
maintain a register of blind and partially sighted people. Being
registered as blind does not necessarily mean that the person is or
ever will be totally without sight.
• On receiving their copy of the CVI – certificate of visual impairment),
a Rehabilitation Worker from Social Care Services will contact you
to discuss your registration and advise you of services and benefits
available to you. Registration is purely voluntary and you should be
asked by the Local Authority if you wish to be registered.
Social care for deafblind children and adults
In June 2009 the Department of Health reissued a guidance for local authorities
called 'Social care for deafblind children and adults' LAC(DH)(2009)6 under
Section 7 of the Local Authority Social Services Act 1970. The guidance expects
local authorities to provide support for deafblind people
The Deafblind Guidance expects local authorities to:
• identify, make contact with and keep a record of the deafblind people locally
• ensure that assessments are carried out by properly trained personnel
• ensure that appropriate services are provided for deafblind people –
remembering that individual services for people who are deaf or who are
blind may not be appropriate for someone who is both deaf and blind
• ensure that they have access to fully trained, one-to-one support workers if
necessary
• provide information in a suitable format which is accessible to deafblind
people
• ensure that a senior manager is given responsibility for deafblind services.
References
•
•
•
•
•
•
•
•
•
•
•
BATOD www.batod.org.uk/index.php?id=/articles/teaching/archive/peripatetic.htm
Dunnings, Mark http://ushersyndromeblog.blogspot.com/
Gallaudet University
– Regional and National Summary Report of Data from the Annual Surveys of Deaf and Hard
of Hearing Children and Youth 2004-5 (Number of children 3143)
Moller, Claes
– Transcript: www.earfoundation.org.uk/downloads/deafblindness_issues_moller.pdf
– Lecture: www.hearingseminars.com/p73458875/
NDCS Genetic Councelling www.ndcs.org.uk/document.rm?id=3168
NDCS Fact Sheet
http://www.ndcs.org.uk/family_support/our_publications_m/balance_disorders.rma
NDCS/SENSE Vision Care for Your Deaf Child
– www.ndcs.org.uk/search_clicks.rm?id=3412&destinationtype=2&instanceid=157905
NIDCD National Institute on Deafness and other Communication Disorders
– www.nidcd.nih.gov/health/hearing/usher.asp
Pearl, Fiona But did I need to know? Talking Sense Vol 47 No1 Spring 2001
www.sense.org.uk/publicationslibrary/allpubs/talking_sense/tsarticles/2001/cochlear
Southwell, C (2003) Assessing Functional Vision – children with complex needs London: RNIB
University of Western Ontario
– Online powerpoint:
www.physpharm.fmd.uwo.ca/undergrad/sensesweb/L10Balance/L10Balance.swf
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