What Is CVI?
How is CVI different from other visual impairments?
There are fundamental differences between CVI and ocular visual impairment.
CVI, also known as cerebral/cortical visual impairment, is different from other forms of visual impairment because it is brain-based. This results in unique visual deficits related to the higher-order visual processing pathways of the brain, not the eye.1 Children with CVI have difficulties not only with seeing, but with interpreting what is perceived by the eyes.2 Characteristic behaviors should be assessed with a CVI-specific functional vision assessment.3
Because the brain has the ability to change, known as neuroplasticity, it can develop new neuronal connections in spite of damage to the visual processing centers and pathways.4 The functional vision of a child with CVI can improve. Over time, a child with CVI may improve their functional vision and access to their visual world, unlocking their learning and social potential.5
NIH defines CVI and helps us understand its differences from other visual impairments
In November 2023, the National Institutes of Health (NIH) convened a CVI Workshop to bring greater clarity and consistency to how CVI is understood. Experts from ophthalmology, optometry, and neurology came together to develop this working definition grounded in research, clinical insight, and expert consensus. The process also addressed key gaps in current definitions and diagnostic approaches.
“The NIH CVI Working Group proposes that CVI is a neurodevelopmental disorder characterized by deficits of visual function and functional vision that are caused by neurologic damage to visual pathways and processing areas in the brain.”
In addition to a doctor’s diagnosis, children with CVI should receive an appropriate functional vision assessment with a specific protocol for CVI that accounts for the differences between CVI and ocular visual impairment. The CVI Range© is currently the only educational tool that assesses the degree of impact on the functional vision of a child with CVI.3 Traditional assessments (ocular, educational, and psychological) fail to accurately gauge the ability and understanding possessed by a child with CVI. However, through the use of an intentional, systematic approach and methodology, guided by assessment, children with CVI can learn to understand the world around them and achieve academically, thrive socially, and acquire independent life skills.
CVI Working Definition
CVI Diagnosis and Care
References
1 Jan, J.E., Groenveld, M. (January 1993). Visual Behaviors and Adaptations Associated With Cortical and Ocular Impairment in Children. Journal of Visual Impairment and Blindness, 87(4).
2 Martín, M. B., Santos-Lozano, A., Martín-Hernández, J., López-Miguel, A., Maldonado, M., Baladrón, C., Bauer, C. M., & Merabet, L. B. (2016). Cerebral versus Ocular Visual Impairment: The Impact on Developmental Neuroplasticity. Frontiers in psychology, 7, 1958. https://doi.org/10.3389/fpsyg.2016.01958
3 Roman-Lantzy, C. (2018). Cortical Visual Impairment: An Approach to Assessment and Intervention. 2nd ed., New York, NY: AFB Press.
4 Ozturk, T., Er, D., Yaman, A., & Berk, A. T. (2016). Changing trends over the last decade in the aetiology of childhood blindness: a study from a tertiary referral centre. The British journal of ophthalmology, 100(2), 166–171. https://doi.org/10.1136/bjophthalmol-2015-306737
5 Kong, L., Fry, M., Al-Samarraie, M., Gilbert, C., & Steinkuller, P. G. (2012). An update on progress and the changing epidemiology of causes of childhood blindness worldwide. Journal of AAPOS : the official publication of the American Association for Pediatric Ophthalmology and Strabismus, 16(6), 501–507. https://doi.org/10.1016/j.jaapos.2012.09.004