CVI Awareness. Diagnosing and Knowing Your CVI Learner

Cortical Visual Impairment (CVI) is the leading cause of visual impairments in the United States. Uniquely, the number of people with this vision impairment will continue to increase as medical advancements are better able to assess and treat individuals with neurological diagnosis.  

Historically, individuals with CVI have had a hard time getting this diagnosis.  Since this is a brain-based visual impairment, an individual may have perfectly healthy eyes.  Imagine for a moment that you have concerns regarding your child’s vision, but every time you get their eyes checked, you get a clean bill of health.  In your gut, you feel something isn’t right.

Diagnosing CVI

According to Christine Roman-Lantzy, Ph.D, a diagnosis of CVI includes three parts.  

First, a child with CVI has an eye exam that does not explain their present level of vision.  This means that even if the ophthalmologist indicates the child has nystagmus (involuntary shaking of the eye), this would not explain why the child is not able to recognize faces of those most familiar to the child.

Second, a child would have a history of a brain condition, trauma, or damage associated with CVI.  Some of the common conditions we may see are asphyxia, encephalopathy, periventricular leukomalacia (PVL), seizure disorders, intraventricular hemorrhage (IVH), or a traumatic brain injury (TBI).  

This does not mean every one with one of these conditions or other structural brain abnormalities also has CVI.  Simply, these individuals could be considered at risk and should be monitored if there are vision concerns.  Remember, this is one of the three elements necessary for identifying CVI.

Lastly, we look for the ten visual and behavioral characteristics as outlined by Dr. Christine Roman-Lantzy.

• Color preference
• Need for movement
• Visual latency
• Visual field preference
• Difficulty with visual complexity
• Need for light
• Difficulty with distance viewing
• Atypical visual reflexes
• Difficulty with visual novelty
• Absence of visually guided reach

So, if it is so hard to diagnose, how do we know it is the leading cause of visual impairments?  Sadly, although the diagnosis is hard to obtain officially, it is still the most prevalent diagnosis.  Can you imagine if we had a better system to ensure no children fell through the cracks?  How many children are potentially impacted by this and have yet to receive proper medical and educational support to accomodate for their vision loss?

The good news is that the functional vision of children with CVI can and should be expected to improve.  Unlike with an ocular loss, which typically maintains or declines,  when individuals with CVI are provided with regular meaningful interventions, they can develop their functional use of vision.

CVI meltdowns are not tantrums  

Have you ever heard or witnessed a CVI meltdown?  While they might look like a child throwing a tantrum, they are not.  You might observe an individual screaming and lying on the floor, refusing to stand or walk, physical aggression toward themselves or others, or even them trying to escape.  Much like everything that surrounds Cortical Visual Impairment (CVI), no two learners with CVI look alike. This includes their meltdowns.

Unlike a tantrum, CVI meltdowns usually occur due to an overwhelming amount of sensory input.  Picture this: we all have an ‘overwhelm bucket.’  Throughout our day, things will fall into our bucket.  These may not be the same each day either.  These stimuli that add to our buckets could be lights, background noise, smells, physical touch, unpredictability, novelty, speed of stimuli, movements, and the list goes on.  Sometimes, things we enjoy can also add to our ‘overwhelm bucket’.   

There is good news! While not always, usually a CVI meltdown can be avoided.  Matt Tiejen has taught us that when we do not have a balance between the complexity of the visual target and the complexity of the environment, what Matt refers to as the visual battery is being depleted.  In this example, when we do not have a balance, we are putting too many drops into the ‘overwhelm’ bucket.

By finding a balance, we are trying to control how often a drop is put into the bucket at a manageable rate.  Still, we need to give the bucket a way to drain throughout the day.  For a learner with CVI, this means a time when we are giving them a break from needing to use their vision.  A calming activity, some time alone, or maybe a preferred activity could be what your learner needs to help empty their bucket before it overflows.  Providing a well balanced day with plenty of opportunities to slowly drain the bucket, before it becomes too full, is essential for avoiding the CVI meltdown. 

Know Your CVI Learner

Knowing your learner and their signs will always be the best tool you can have.  Even if you think you have done your best to balance the day, when you see the child beginning to exhibit those warning signs, the team should know the child is trying to communicate to you.  The learner is telling you they are hitting their threshold and they need a chance to re-charge.  

This is not a power struggle.  This is not a behavior that needs redirection or consequences.  It is at this time the team should give the child a chance to re-charge.  Additionally, the team should look at what is next in the routine to determine if any other additional accessibility changes need to be made.  That means if math is next and typically the child participates visually, the complexity of the visual task and environment need to be modified in order for the child to use their vision again. OR, and this is big, maybe they need to participate using a different modality all together.  Vision may not always be the best learning modality.