cvi - sfasu

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Cortical visual impairment (CVI) occurs
when there is damage to the visual cortex,
and/or the posterior visual pathways within
the brain. The eye generally does not have
any internal damage although CVI can
also be evident in children who do have
ocular damage. The reduction of vision is
due to neurological damage which hinders
visual stimulation from being organized and
interpreted by the brain.
As the name
suggests, Cortical
Visual Impairments
affect the brain’s
visual cortex
and/or visual
pathways that
relay information
from the eyes.
Children who are cortically visually impaired have a
medical history that involves neurological impairment due to
conditions such as asphyxia, cerebral hemorrhage, infection
of the central nervous system, and/or trauma.
It is noted the following behaviors have been associated
with cortical impairment:
 Visual performance can be quite variable, simply put,
some days are better than others. Visual functioning
can even change from hour to hour with some
children.
 Visual field defects may also be associated with CVI
due to specific neurological damage.
 Movement cues, especially in the peripheral fields can
often stimulate a visual response. Visual interpretation
may be improved for some children when they are
actually moving as opposed to standing still.
 Color vision does not seem to be affected.
Assessment of vision of children with
CVI is an ongoing process that should be
discussed several times during the first
year and at least twice a year in
preschool age children. The most typical
feature of functioning of children with
CVI is variation caused by changes in
brain functions because of the basic
condition and changes caused by
varying effects of medications and
fatigue.
It is important to understand the base of
information known about CVI must be
analyzed to each child as an individual. Each
characteristic of CVI may or may not fit an
individual child. The information that does “fit”
will help parents and teachers to design a
home and/or school program that is tailored to
each child’s needs.
The vision of a child with CVI could impact
the image quality changes, oculomotor
deficiencies, changes in the function on the
primary and the associative visual cortices,
changes in compensatory functions.
Objects of varying colors, textures, and shapes may be
used with students who have CVI. Parents and teachers
should decide what objects are typically used with the child
during everyday activities or routines. To establish familiarity,
the same object(s) should be used each time. Objects
should be visually, tactually, and verbally presented at the
onset of the activity and then talked about as the child
experiences their function. The exact style of presentation
will vary according to each child’s general learning style
and needs.
Light can be helpful in focusing students’ attention to
objects or used in mobility adaptations. Light boxes are often
used when working on skills such as tracking or targeting
objects.
Light Box
Easter eggs with LEDs
inside are easy to make
and visually stimulating.
A sound book modified to avoid visual
distractions.
The main focus is for the child
with CVI to control visual input in
order to avoid overstimulation.
 Reduce extraneous sensory
information from the child’s
“working/playing
environment”.
 The use of touch should be a
primary means of introducing
information.
 Language is very important
for information about the
object or visual situation. Use
labels that include description
words. Tell the child what
she/he is “seeing”.
Currently, there is no precise
treatment for CVI, and many
rehabilitative measures are unproven.
Clearly, there is a great need for
additional research on treatment and
management of this common and
complex disorder.
Richard Buckholt was born on July 22, 2007 the first son in a sea
of women. The day after he was born, concerns about the size of his
head were expressed. His head was extremely small; it did not make
it on the growth chart. Tests were done for exploration. He appeared
to being doing well, we thought all of the tests were precautionary
and everything was fine. Richard had a head ultrasound and it
revealed that he was missing part of his brain and had additional
abnormalities. The ultrasound could not provide a clear picture and
we were instructed to schedule a MRI to review his brain in further
detail after he was three months of age. Thankfully, Richard was
nursing well and he was able to come home to his family. The next
few months were filled with tests and specialists. All of his major
organs needed to be checked to rule out additional complications.
The family saw just about all of his insides, all of which were
functioning and doing well. The big test was the brain MRI. The MRI
revealed that Richard’s brain was missing parts and the rest was
abnormal. Today the family is still learning what all of this will mean
for his life.
Richard struggles with seizures which the
family tries to regulate with medication. He is
severely visually impaired. Richard has a G-J
tube and is feed by j-tube (into his intestines)
for about 20 hours a day. He struggles with
chronic vomiting and Richard has been in and
out of the hospital for them frequently. At
home the family continues to pump his
stomach, by a big suction machine, several
times a day for about 30 minutes.
Developmentally he is close to a newborn. He
cannot hold his head for more than a few
seconds. He needs constant full support.
Richard sees a list of doctors and specialists on a regular basis:
neurologist, ophthalmologist, occupational therapist, physical
therapist, feeding therapist, vision therapist.
One of the big questions for the family is his condition, handicap,
label, etc. The mother states that it all depends on which doctor we
are seeing and what part of his body that particular doctor is looking
at. His family does know that the doctors, therapists, and insurance
use these fancy labels to get Richard services, treatment or therapy
but not one single term describes Richard.
 To the neurologist: ACC, seizure disorder, cerebral dysgensis,
microcephaly, pontocerebellar hypoplasia
 To the occupational and physical therapists: cerebral palsy,
developmental delays, mixed muscle tone
 To the ophthalmologist and vision therapist: cortical visual
impairment, optic nerve hypoplasia
 To the GI doctor and feeding therapist: feeding difficulties, G-J
tube, chronic vomiting
His mother’s greatest concern is that
Richard is currently not gaining weight at
this time. He is currently losing hair and his
skin is peeling. While tests have been
done to try to find out why Richard was
not sleeping this year it might all be
adding up to malnutrition.
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Anthony, T. Texas School for the Blind and Visually Impaired (TSBVI).
Cortical Visual Impairment An Overview of Current Knowledge. Retrieved
July 15, 2013, from http://www.tsbvi.edu/programand-administrativeresources/3276-cortical-visual-impairment-anoverview-of-currentknowledge
Hyvärinen, MD, L. (2004, ). American Printing House for the Blind.
Understanding the Behaviours of Children With CVI.Retrieved July 17,
2013, from http://www.aph.org/cvi/articles/hyvarinen_1.html
Demehak, M. University of Nevada, Reno. Tips for Home or School
Cortical Visual Impairment. Retrieved July 18, 2013, from
http://www.unr.edu/ndsip/tipsheets/cvi.pdf
Good MD, W., Jan MD, J., Burden BS, S., Skoczenski PhD, A., & Candy PhD,
R. American Printing House for the Blind. Recent advances in cortical
visual impairment. Retrieved July 18, 2013, from
http://www.aph.org/cvi/articles/good_1.html
Welcome to APH CVI. (n.d.). American Printing House for the Blind.
Retrieved July 19, 2013, from http://www.aph.org/cvi/index.html
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