Cortical Visual Impairment
I recently attended a conference to educate myself on Cortical Visual Impairment, one of my son’s diagnoses. It was so enlightening and revolutionary and added in a big heap of mom guilt.
When you have a child with multiple disabilities, it can be tough to decide which one to prioritize or focus on. After this conference and digesting what I learned there, I am definitely moving CVI to the top of the list. CVIConnect is the leading resource on this to date.
Author’s note: Since this post is over 10 years old, I can comment on his progress. I can tell you that it was life-changing (duh!) to make CVI accommodations a priority.
I was initially overwhelmed by all the changes, but it’s much easier once you get into that pattern of thinking. Now, for almost everything we buy for Kevin (feeding utensils, plates, anything really), we think about what it will look like for him.
Please consult your child’s medical team with specific concerns. Much of what is on the internet today regarding CVI information is not evidenced based.
What is CVI Cortical Visual Impairment?
There are two types of visual impairments. Those that eye based (a problem with the actual eye) and those that are brain-based (a problem with the brain). CVI is brain-based. There is damage or atypical structures in the visual pathways. Visual processing is compromised to varying degrees.
The eyes get the image, and the brain perceives it. However, it cannot categorize the information or sort the information. The brain cannot label it or put meaning to it.
This is why glasses do not fix the problem. Children may look at objects frequently. Looking at an item does NOT mean that they can interpret it.
Causes of Cortical Visual Impairment
The causes of CVI include, but are not limited to:
- hypoxia (a lack of sufficient oxygen in the body’s blood cells)
- ischemia (not enough blood supply to the brain), all of which may occur during the birth process
- developmental brain defects
- head injury
- Hydrocephalus (when the cerebrospinal fluid does not circulate properly around the brain and collects in the head, putting pressure on the brain)
- infections of the central nervous system, such as meningitis and encephalitis
- neurological conditions such as chromosome disorders
- Traumatic Brain Injury (TBI)
Is this the same as cortical blindness? It is widely accepted that “cortical blindness” is not an appropriate diagnostic term for children with early, acquired visual impairment due to non-ocular causes.
Symptoms of CVI
• A preference for color, predominantly red and yellow, but can be any color. Children are drawn to rich, highly saturated colors. Color is a visual anchor for them.
• Need for movement, especially rapid movements. May fixate on fans or other similar objects. Older children (in the classroom) may not be able to “not look” when visually distracted by a ceiling decoration or movement in the hallway or outside the classroom window. This includes shiny things, mylar, and similar items that will draw their attention.
• Visual latency, meaning the patient’s visual responses are slow and often delayed. They need wait time to respond. With proper interventions, the latent times can greatly improve.
• Visual field preference—the patient sees better in one area, i.e. right peripheral.
• A difficulty with visual complexity, meaning not seeing an object when other stimuli, such as sounds, are present. If an environment is sensory complex, they must choose which sense they will attend to. This includes the ability to analyze faces, which are very visually complex. This means that the kids will often avoid looking into unfamiliar faces.
• Light-gazing and non-purposeful gaze. Since they cannot sort and categorize what they see, if they cannot find something meaningful (to them) to look at, the child will have a non-purposeful gaze.
• A difficulty with distance viewing (often mistaken for nearsightedness). This is due to what could be a visually complex environment. In these instances, the child will use memory to override their vision skills, making it appear as if they can see–because they will be able to navigate familiar environments based on memory.
• Atypical visual reflexes, such as not blinking when you tap the bridge of the nose or visually threaten the child with fingers (ie, act as if you are going to poke in the eye, judge response.)
• A difficulty with visual novelty, meaning the patient prefers looking at familiar objects. They are often confused with a hyperfixation in something since they will fixate and prefer the familiar. Prefer objects they already know. Therefore, the brain doesn’t have to “sort out” the information. They have to be taught from the perspective of building a visual schema to work from, as they have none. They have no previous visual experiences or knowledge to draw from; it has to be taught.
• An absence of visually guided reach. “Look, look away, reach.”
I don’t like the word ‘treatment’ because that implies a fix or a cure.
Eg: Do some therapy for X number of months, and bingo! No more CVI!
It doesn’t really work that way. Ask your child’s doctor.
Your child may need vision services and/or orientation and mobility services. Try to find providers that are familiar with the latest information on CVI. Note: a CVI range assessment exam IS NOT the same as a Functional Visual Assessment (FVA). I recommend getting both for your child.
Be careful when choosing assessments, ranges, etc. Again, not everything that is out there has been published by a doctor, nor is it evidence-based.
Shared Behaviors DOES NOT mean Shared Diagnosis.
Here are some behaviors that kids with CVI exhibit:
- lack of facial regard/eye contact
- delayed play skills
- delayed speech/language skills
- perseveration on familiar objects
- delayed social skills
Sound like anything else you know? When assessing your child, explore ALL the options, as many physicians are still unfamiliar with CVI.
Make sure your IEP team is aware of this diagnosis and that strategies are implemented to help your child visually access his/her education.
Ask if your school district or county has TVIs (teachers of the visually impaired) and determine if this will help your child. Request a Functional Vision Assessment or FVA.
From Boston Children’s Hospital-Confusing diagnostic entities include:
- delayed visual maturation
- autism spectrum disorders
- severe bilateral central scotomata (with eccentric fixation)
- dyskinetic eye movement disorders
- profound mental retardation
IEP Goals and Accommodations for CVI
It all begins with the evals! So make sure you request a functional vision assessment (FVA) and an Orientation and Mobility (O&M) assessment. From there, the team should decide if the child needs direct teaching or just accommodations.
We did several years of direct teaching of vision and O&M. O&M is another special education acronym. It stands for Orientation and Mobility.
My son had both direct and consult services with a TVI for several years.
Myths and Misconceptions about CVI
“The child’s vision will vary daily, hour to hour.” FALSE. The child’s visual abilities do not change; the environment may change.
And unlike many ocular (eye-based) problems, CVI patients can improve their vision. Improved vision feeds cognition and builds those neuropathways.
This means actual learning and improvement in skills can occur rather than just improving coping skills.
his post was originally written in 2012 but was recently updated to fix links and formatting.