Cortical/Cerebral Visual Impairment in Children
What Is Cerebral/Cortical Visual Impairment (CVI)?
Although vision or sight, as a sense, is primarily associated with the eyes, in reality, vision is the product of a complex system of which the eyes are only one part. The processing of visual information—the receipt of visual stimuli through the eyes, its interpretation by various brain centers, and its translation into visual images—has been estimated to involve as much as 40 percent of the brain. When this process is disrupted, the visual systems of the brain do not consistently interpret or understand what the eyes see, and visual impairment is the result.
The resulting visual impairment is considered a cerebral or cortical visual impairment (CVI).
CVI is also known as neurological visual impairment, traumatic brain injury, and brain-damage-related visual impairment. CVI may be temporary or permanent.
Vision loss due to neurological damage to the brain affects both children and adults, and the complexities involved have been the subject of much discussion and debate throughout the community of professionals who provide vision-related services. Consensus has not been reached on the definition, assessment, and services needed to address vision loss of this kind, and much research is needed to determine effective educational, rehabilitative, and medical practices in this area.
How Is CVI Diagnosed?
A diagnosis of CVI is made when an ophthalmologist reports normal eye anatomy, yet the child is exhibiting signs of vision loss. An MRI of the brain will usually confirm neurological or anatomy irregularities.
Are There Treatments for CVI?
There may be treatments for the underlying causes of CVI. Regarding vision only, it is thought that CVI can improve over time.
How Would You Describe the Eyesight of One with CVI and How Will My Child Function with It?
The degree of vision loss may be mild or severe and can vary greatly, even from day to day.
People with cerebral/cortical visual impairment have difficulty using or understanding what their eyes see. For example, they may have trouble recognizing faces, interpreting drawings, perceiving depth, or distinguishing between background and foreground. Children with cerebral or cortical visual impairment are often able to see better when told in advance what to look for. Additionally, many with CVI can see better when the target object is moving.
Children with CVI may have sensitivity to light or may fixate on light, may have poor depth perception, and may have better peripheral vision than central vision.
Your child’s teacher of students with visual impairments should perform a functional vision assessment to determine how your child uses remaining vision and a learning media assessment to determine which senses your child primarily uses to get information from the environment. These assessments, along with an orientation and mobility assessment conducted by a mobility specialist, will give the team information needed to make specific recommendations for your child to best access learning material and his or her environment.
You may learn your child has difficulty recognizing facial expressions, accessing information in a cluttered environment, identifying images or letters when your child is stationary or the visual target is stationary, using vision for extended periods of time, utilizing the central field of vision, or difficulty traveling safely. Your child may benefit from travel training from the mobility specialist, increased contrast of the environment, increased contrast of print by using a CCTV or screen-magnification software, increased or varied room and task lighting, decreased visual clutter, head support and breaks from using vision, presenting objects in your child’s peripheral field of vision, and presenting a moving object for optimal viewing.
Your child may also be taught to complete tasks without use of vision. Your child may be taught braille, use of screen-reading software to use the computer, and other techniques for performing life skills and academic tasks.
Resources for Families of Children with CVI
- Cortical Visual Impairment, Traumatic Brain Injury, and Neurological Vision Loss from the American Foundation for the Blind
- Cortical Visual Impairment: An Approach to Assessment and Intervention by Christine Roman-Lantzy
- Vision and the Brain: Understanding Cerebral Visual Impairment in Children, edited By Amanda Hall Lueck and Gordon N. Dutton
- CVI: The Conversation Continues by the American Printing House for the Blind
- Join the FamilyConnect community and connect with other families who have children with CVI