What Is CVI?
CVI: Brain-Based Visual Impairment
CVI, also known as cerebral/cortical visual impairment, is a brain-based visual impairment. It’s a disability of access. The eyes can see, but the brain can’t interpret the visual world.
CVI is the leading cause of visual impairment in children in developed countries.1,2,3 Unlike conditions resulting within the eyes themselves, CVI results from a problem in the visual pathways or processing centers of the brain. This brain-based visual impairment is a condition affecting the brain's ability to process visual information. Children with CVI may have healthy eyes, but their brains struggle to make sense of the visual signals. The condition is distinct from ocular visual impairment because the cause lies within the brain rather than the eyes. This causes a spectrum of challenges.
The number of children with CVI is increasing, elevating it to a public health concern of high significance.4 This has occurred because of medical advances that have led to better visual outcomes in retinopathy of prematurity, congenital glaucoma, and congenital cataracts, and at the same time, improved survival of children with central nervous system diseases. The National Institutes of Health website cites a CVI prevalence of 10.5% of all children with developmental disabilities.5
Leading cause of visual impairment in children in developed nations
%
Studies indicate many children with visual impairments in the US, UK, New Zealand and other developed economies have CVI
%
CVI is increasing in developing nations, accounting for nearly half of visually impaired children in India
Causes of CVI
Ocular disease and ocular motor disorders can co-exist in a child with CVI, but these issues will not fully explain the child’s visual loss. Pediatric CVI is a brain-based visual impairment that occurs before puberty but may go unrecognized until later in life. Some common causes of CVI include:
- Premature birth and related complications
- Traumatic brain injury
- Neonatal infections such as meningitis or encephalitis
- Genetic and metabolic disorders
- Stroke or other vascular abnormalities
“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.”
Signs and symptoms of CVI
Children with this brain-based visual impairment (CVI) exhibit a range of characteristics identified in medical and educational research.6 Some characteristics of CVI include:
- Poor and/or delayed visual attention
- Preference for certain colors
- Difficulty recognizing faces or objects
- Preference for looking at moving objects rather than still ones
- Sensitivity to visual clutter or difficulty in crowded environments
- Difficulty with fast-moving objects
For example, parents and vision teachers may report that the child interacts visually in a more focused way with an uncluttered workspace and lower sensory complexity, prefers to gaze at light, or does not respond to people or large objects from across the room. These anecdotes suggest pediatric CVI.
Diagnosing brain-based visual impairment
A CVI diagnosis is usually made by an ophthalmologist, neuro-ophthalmologist, neurologist, or, in some cases, an optometrist. Children with CVI have a history of a neurological issue due to a medical cause such as, but not limited to, perinatal hypoxia, prematurity, hydrocephalus, or genetic disorders. Children should have a full eye examination and may need to be followed over time or undergo a workup to exclude other causes of vision loss, such as inherited retinal disorders or delayed visual maturation. While some children will have a co-existing ocular condition, this will not fully explain their visual loss. Brain-imaging studies may or may not indicate the neurological issue.
Children with CVI will exhibit some or all of the unique visual and behavioral characteristics as described in the CVI Range©.7 Early identification of CVI is crucial to minimizing its impact on a child’s learning and overall development. Accurate diagnosis and effective intervention require a collaborative, multidisciplinary team, bringing together ophthalmologists, neurologists, educators, and a range of specialists and therapists.
Impact of CVI on daily life and education
CVI can hinder a child’s ability to access learning materials, which may impact both educational progress and overall development. It can also interfere with daily activities, making everyday tasks more challenging.
Parents and caregivers often encounter difficulties navigating complex healthcare systems, locating appropriate resources, and advocating effectively for their child. While awareness of CVI is growing, it is still limited—leading to delays in both diagnosis and critical early intervention.
Brain-based VI & neuroplasticity
The brain has the ability to change, known as neuroplasticity, and develop new neuronal connections in spite of damage to the visual processing centers and pathways. Over time, a child with CVI may improve their functional vision and access to their visual world, unlocking their learning and social potential. By systematically building connections in the brain with appropriate intentional interventions, a child with CVI can see more.
Professionals and parents who care for children with CVI frequently share feelings of frustration in confronting the questions of:
“What does this child see?”
“How does this child see?”
“How can I improve this child’s ability to see?”
Join us. The Pediatric Cortical Visual Impairment Society is a community of doctors, educators, therapists, parents, and advocates who are working together to answer these questions. Through interdisciplinary education and research, and ongoing advocacy for awareness and resources, we hope to improve the quality of life for all children with CVI.
CVI Fact Sheet
CVI Working Definition
References
1 Nielsen, L.S. et al. (2007). Visual dysfunctions and ocular disorders in children with developmental delay. I. prevalence, diagnoses and aetiology of visual impairment. Acta Ophthalmol Scand, 85: 149-56. https://onlinelibrary.wiley.com/doi/10.1111/j.1600-0420.2006.00867.x
2 Hatton, D.D. et al. (2007). Babies Count: the national registry for children with visual impairments, birth to 3 years. JAAPOS, 11: 351-5. https://www.jaapos.org/article/S1091-8531(07)00135-8/abstract
3 Matsuba, C.A., Jan, J.E.. (2006). Long-term outcome of children with cortical visual impairment. Dev Med Child Neurol, 48: 508-12. https://pubmed.ncbi.nlm.nih.gov/16700945/
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 Swaminathan, M. (2011). Cortical visual impairment in children — A new challenge for the future? Oman Journal of Ophthalmology, 4(1), 1–2. http://doi.org/10.4103/0974-620X.77654
6 Roman, C., Baker-Nobles, L., Dutton, G.N., et al. (2010). Statement on Cortical Visual Impairment. JVIB, 104:69-72. https://www.researchgate.net/publication/298853604_Statement_on_Cortical_Visual_Impairment
7 Roman-Lantzy, C. (2018). Cortical Visual Impairment: An Approach to Assessment and Intervention. 2nd ed., New York, NY: AFB Press.