Download Cortical Visual Impairment (CVI)

Cortical Visual Impairment (CVI)
Case Study for
Gilson Z.
This case study was conducted with Gilson’s vision teacher. Gilson was born 9/24/1999. The
onset on his condition was congenital. He was born premature and had birth asphyxia which resulted
(among many other things) in him having CVI. He is currently placed in a Life Skills classroom. Based on
the most current report from an eye specialist, and upon the results of his Functional Vision Evaluation,
it determined that Gilson does qualify as a student with visual impairments under Texas law and current
Commissioner’s Rules. Gilson is currently in good general health. His mom reports that Gilson will be
undergoing foot surgery to release the tendons to help with his legs and feet.
The most current report of an eye exam which is available for Gilson is dated 5/6/08, and was
based on an examination performed by Malcolm L. Mazow, M.D. of Houston. The diagnosis given is
bilateral third nerve paralysis, exotropia, hypermetropic astigmatism, bilateral optic atrophy (both eyes),
developmental delay and a seizure disorder. Bilateral third nerve paralysis is pathologic condition in
which there is a weakness of the muscles innervated by the 3rd (oculomotor) cranial nerve. The eye
usually deviates outward and slightly downward and has an extremely droopy (ptotic) upper eyelid
without its lid fold; sometimes the pupil is dilated and accommodation is reduced.
His teacher stated that due to Gilson’s dark eye color and his eye lids covering part of his pupil,
she was unable to test his pupillary response. When she did do some tests, Gilson did demonstrate a
blink to threat reflex when an object was unexpectedly moved close to his eyes. The muscle balance of
Gilson’s eyes was tested by a cover- uncover test. When one eye is covered up the other eye moves
outward (exotropia). This result indicates that Gilson probably does not use both of his eyes together.
Common educational implications of this condition are:
Absence of depth perception, eyes are not working together, possibility of some field loss, blurred
vision, may need more time to adjust to new situations, may tire easily, needs good contrast, lighting
and glare reduction, poor tracking skills.
Dr.Mazow considers Gilson to be legally blind. He has recommended lid scrubs to treat
Blepharitis and the prognosis is permanent. In addition to Gilson’s visual impairment, he also meets
eligibility criteria for the following: multiply disabled, other health impairment, mental retardation and
speech impairment. These additional impairments tend to affect Gilson’s vision in the following ways:
interpreting visual input, verifying visual input through the auditory channel, inability to verbally express
information obtained visually about his environment.
Charlotte Conner, Regan Marburger, Sarah Mays, Kelly Hill, Christy Moody
Page 1
During his testing with his vision teacher, several activities were performed in order to assess the
efficiency with which Gilson can move his eyes. Specifically, an effort was made to assess the
effectiveness of Gilson’s ability to:




Visually fixate – look at an object and keep his eyes locked on the target,
Track – use his eyes to follow a moving target without moving his head,
Scan – sweep his eyes across the environment to locate a visual target, and
Focal shift – rapidly and efficiently move his eyes from one visual target to another.
Results from the tests listed above indicated that Gilson has the following ocular motility capabilities.




Visually fixate – Gilson is able to maintain his eyes on a specific visual target.
Track -- Gilson is able to track an object both vertically and horizontally with head
movement only.
Scan – Gilson is able to scan his environment, as well as search for a preferred item.
Focal shift -- Gilson is able to move his eyes from one visual target to another.
According to Gilson’s vision teachers, he seems to respond to bright, neon colors. He is not able
to match or name colors. His teacher stated that in order to get a better idea of the functional implications
of Gilson’s visual impairment, he was observed focusing on different size objects at various points in
space. These tasks can be categorized as near, intermediate, and distance vision abilities. Results were:
 Near – Gilson was able to locate a ½” piece of cracker from 6” on the clear tray of his
wheel chair.

Intermediate – He is able to visually attend to a program on the computer from 18”and
the small Patty Cake Patti from 18”Distance – He is able to follow individuals from 4’
and visually attend to the Large Patty Cake Patti from 3’
The ability to coordinate visual input with movement is critical for many tasks students are asked
to perform in school. Gilson is able to reach for objects and individuals. He can grasp objects and bring
them to his mouth. He is able to move his mobility device a short distance by using one leg to push
himself forward when the mobility device is locked in the forward position.
Gilson will benefit from using the following types of learning media in the classroom: bright,
bold pictures and toys; lighted toys; lights of varying colors and intensities; visual cues to direct vision;
television; videos; real objects; hand-over/under-hand modeling; physical prompting; varying textures and
temperatures; toys or objects with interesting tactual aspects; verbal descriptions and guidance;
conversation; taped materials; environmental sounds; toys with auditory components.
Due to Gilson’s developmental level, he is not a reader or writer. He benefits from a multisensory approach to his learning. This provides him with the opportunity to gather information at his
functional level through all sensory modalities.
Charlotte Conner, Regan Marburger, Sarah Mays, Kelly Hill, Christy Moody
Page 2