Cortical Visual Impairment

What is it?How do we Adapt?

According to the American Printing House, aph.org, the definition for medical purposes: Cortical visual impairment (CVI) may be defined as bilaterally diminished visual acuity caused by damage to the occipital lobes and or to the geniculostriate visual pathway. CVI is almost invariably associated with an inefficient, disturbed visual sense because of the widespread brain disturbance

According to the American Printing House, aph.org, the definition for educational purposes: Cortical visual Impairment (CVI) is a neurological disorder, which results in unique visual responses to people, educational materials, and to the environment. When students with these visual/behavioral characteristics are shown to have loss of acuity or judged by their performance to be visually impaired, they are considered to have CVI.

There are 30 areas of the brain that processes vision and 10 areas of the brain stem - In children with CVI, information must be channeled to these areas of the brain rather than the affected primary area

Defined

Cortical visual impairment is the leading cause of visual impairment in children in the US

Optic Nerve Hypoplasia is the second leading cause of visual impairment in children in the US

Retinopathy of Prematurity the third leading cause of visual impairment in children in the US

Prevalence

Can be congenital

Can be acquired

May also exist with other visual conditions such as: optic nerve atrophy, hypoplasia, dysplasia, or retinopathy of prematurity

CVI

Asphyxia Hydrocephalus Cytomegalovirus Premature Birth Metabolic disorder Periventricular Leukomalacia Seizure Disorder Brain Bleeds Trauma Shaken Baby Syndromes Exposure to toxins & drugs ETC.

Causes

Common Characteristics

Normal optical structure

Normal coordinated eye movements with the possible exception of the presence of eye movement that is similar to nystagmus

Normal color perception

Normal Eye Exam

Novelty: Objects that the child are not familiar with

More able to notice objects that are familiar to them

Example: Toys they have played with or educational tools they have used over a period of time

Difficulties with Visual Novelty

Too much visual, auditory, and/or tactile information at one time

Low Complexity High Complexity

Difficulties with visual Complexity and Environmental Complexity

Environmental complexity include classroom noise, people talking, visual clutter, etc.

• Headphones, ear plugs or sock caps, project boards can be used to eliminate or lessen background noise

• Drapes/sheets, project boards, carousels, may be used to limit or lessen visual clutter

Complexity

Educational materials include, worksheets, whiteboard presentations, board work, etc• Different sizes of typoscopes (reading windows) can be

used to decrease the amount of visual clutter on a page

Complexity

Most typical color preferences are Red or Yellow (because there are more red cones in the retina than any other color)

Distinct Color Prefence

Distinct Color Preference

Speech Pathologist can wear Red Lipstick so the child’s vision will be directed toward their lips

Loss of vision in area(s) of sight

90% have visual field deficits

Lesions in temporal fibers; upper field loss

Lesions in parietal fibers; lower field loss

Lesions in one hemisphere; field loss in opposite half of each eye

Visual Field Deficits

Child’s eyes are focused on something/someone but it appears he is looking through it

Non-Purposeful Gaze

Child likes to look at lights The child continuously looks at ceiling fans when there is a

source of light The child will move into a sunny area or area with direct

light Note: Some children with CVI demonstrate light sensitivity

particularly in the early stages of CVI

Light Gazing Behaviors

Light Gazing

Light Gazing

Light Gazing

Light Gazing

Light Gazing

Child sees many service providersin a day. Take pictures of them, put them on transparency, and put them on a light box as a wayof letting the child know they willbe seeing them next. Starts to recognize the picture and the person are the same.

Child takes time to react to something to which he is visually attending

It make take several seconds or minutes for him to “notice” and respond

Visual Latency

Visual Latency

Child sees items that have a movement characteristic. The item may not actually be moving

Attracted to Movement

Movement

Child does not respond to visual threats, such as when an open hand is brought quickly toward the face

Atypical or Absent Visual Threat Response

Brings object close to block out irrelevant background / visual clutter (the effects of figure ground)

Use of Near Space and Close Looking

Distance Viewing

As child resolves difficulties with distant viewing, he is able to see objects further and further away

Atypical Motor Behavior

Child focuses on a person or object

The computer or iPad are an excellent tool to use with children who have CVI. It provides high contrast, two dimensions and fills the child's visual fields to eliminate the effects of figure-ground

There are excellent children’s computer programs that are simple and educational that use bright colors and eliminates visual clutter. Examples: Creature Capers, Creature Cartoons, Creature Antics, Creature features, Creature Magic (from Laureate Learning Systems), Senswitcher.com

Make your own interactive books/games using Microsoft Power Point

Use of Computers and iPads

Scroll n Roll – scrolls print across the screen thus child may be able to read

Tap and See Little Bear Sees Fluidity See Wonderbaby.com for a list of recommended apps for visual

impairment and CVI Shapes Baby Finger Findit Rattle Touch Free Tail Toes Match It Up Speak up: When children speak loud enough, colors and shapes appear iMeba: Cause and effect

iPad Applications

To promote reading use different fonts, colors, and sizes

DogCatBird

To Promote Reading

Lighting

Electronic Magnification

Reading

Dollar Tree or Dollar store: tap and light up, spinner lights, beads, bows, mini strands of lights, solar toys, etc

APH.org Bubble lights purchased at Cracker Barrel Stores

when in stock or Google LED bubble gun for a variety of sources

Garage sells Purchase materials cheaper the day after a

holiday

Materials

Renee Miller, CTVI at OSB Tonya Givens, Secretary, OSB Pam Cox, Special Education Teacher, Union

Schools Abi McClain Student, Union Schools Miss Madge and her students, Union Schools Students at OSB Dr. David Lewerenze, Northeastern State

University College of Optometry Dr. Christine Roman-Lantzy

References and Thank you