Ellen Mazel Discusses Cortical Visual Impairment (CVI)

Ellen MazelEllen Mazel, M.Ed. CTVI works in the Educational Partnerships Program at Perkins School for the Blind. In 2008, Ellen was named National Teacher of the Year for Children with Multiple Disabilities by the Council of Schools for the Blind (COSB). Ellen has expertise in the area of Deaf-Blindness, early intervention, cortical vision impairment, and transition.

I keep hearing the term CVI used but I don’t have a clue as to what it means. Can you tell me what it is? Is it a new term?

CVI is a term that has come into use within the last 10-15 years. The initials stand for “Cortical Visual Impairment” or “Cerebral Visual Impairment”. It is also sometimes referred to as “Neurological Visual Impairment”. CVI is a brain based visual impairment where there has been damage to the visual centers of the brain. Vision is processed in more than 30 areas of the brain. These areas may process movement, relative motion, color, edges, all the aspects that give typically sighted persons functional vision. In CVI, the eyes of the child may be healthy and normal but the child does not use vision in a typical way. Some children also struggle with both CVI and ocular visual impairments. These must be assessed separately and programmed for separately. After looking at several common characteristics, the doctor may determine the child has CVI. These characteristics include attention to specific colors usually yellow and red, attention to movement of items in the environment, light gazing or non purposeful gaze, preference for one visual field, atypical visual reflexive responses, lack of attention to distance, attention to familiar items rather than novel items, poorer visual skills in complex visual or auditory environments, poorer visual skills if positioned poorly and an increased time to visually find items.

Are the strategies used in teaching children with CVI different from the strategies used when working with other children with visual impairments? If so, why is that?

Strategies for CVI are completely different than strategies for ocular loss. With CVI there is a an important focus on improvement. The child must be carefully assessed and the strategies designed to support skills and move to resolve the vision difficulties. Strategies after assessing the child focus on choosing materials and creating environmental adaptations to allow the child to process the visual information to the child’s best abilities. Strategies include use of color, movement, wait time, presentation in the optimal visual field, using familiar items, controlling and using light systematically, reducing visual, auditory and positional complexity, and presenting items in near space.

Sometimes my child appears to see objects around the home and sometimes they do not seem to be able to see them. Why is that?

The apparent fluctuation in visual skills is often a result of change in environments and variations in light levels, visual, auditory and positional complexity. The child may also see familiar items quicker and look at them longer than looking at novel items.

Can you give me any other resources for further information?

Christine Roman Lantzy’s book Cortical Visual Impairment: An Approach to Assessment and Intervention is an excellent tool for learning about CVI, CVI assessment and building strategies. America Printing House for the Blind (APH) has great information on their website. Perkins released a webcast about CVI basics: Cortical Vision Impairment: Assessment and Intervention. Articles by Dr. Dutton, Dr. William Good, Dr. Mary Morse, and Lea Hyvärinen are full of excellent information.