September 9, 2019

What is Cortical/Cerebral Visual Impairment (CVI)?

- Becky Berk

exterior shot of a hospital building

Did you know that the fastest growing cause of visual impairment in children has nothing to do with the eyes?

That’s right.  Vision depends on the brain as much as it does the eyes. CVI, shorthand for Cortical or Cerebral Visual Impairment, essentially means that the brain’s ability to interpret, recognize or process visual information from the eyes is compromised.  CVI can limit a child’s ability to learn visually, even when their acuity (clarity of vision) is high and the structure and function of the eyes are normal.

Since September is CVI awareness month, in this article we talk about the mechanics of this condition, some of the common causes, ways to recognize it and how to get support.

How trauma or injury can lead to CVI

Roughly 40% of the brain is involved with the transmission and interpretation of visual information in some way, so CVI should be a considered whenever damage to the brain is suspected or confirmed.

Neurological damage may occur when a baby is born prematurely, but such damage may also occur in infants born at term or in children who suffer a traumatic brain injury.  The most common cause of CVI-related brain damage is hypoxia (when the brain does not get enough oxygen). The incidents of CVI are increasing in part due to the increased ability to diagnose and treat complications in newborns when there is neurological damage.

Some of the symptoms of CVI

Like most conditions, CVI can range from mild to severe.  The clues that could indicate CVI include visual behaviors such as delayed attention to a visual stimulus, prolonged gazing at a light source, greater attention to objects that are color saturated, particularly bright red or bright yellow, for instance.  Some visual behaviors, such as the lack of a blink reflex to protect the eyes from potential injury, may pose a safety concern.  Other behaviors, such as lack of eye contact when listening to someone speak can be misinterpreted as rudeness or disinterest.  Still other signs indicate a disconnect between vision and body movements, such as a child who looks away before reaching for something. Research continues to map the connection between the areas of the brain that are affected and the impact on a child’s ability to perceive, understand and interpret visual information.

Professional support for students with CVI

A skilled Teacher of Students with Visual Impairments (TVI) can assess the extent and educational implications of CVI, ideally within the context of a collaborative educational team, including parents or guardians.  Instruction can then focus on increasing the child’s ability to complete discrete functional tasks, make intentional choices, learn through visual, auditory and/or tactile channels, and experience joy and success.

Similarly, an Orientation and Mobility specialist (O&M) can assist children and their teams in maximizing safe movement and interacting with their environment, even in cases where children are confined to a wheelchair or have other co-occurring disabilities.

If you or someone you know is exhibiting symptoms of CVI or just need help diagnosing any vision loss problem, please contact us. For assistance specific to CVI or school age children, contact Becky Berk at [email protected], or call 603-565-2405.