Natural History of Cerebral Visual Impairment in Children with Cerebral Palsy
Jessica Galli, Erika Loi, Stefano Calza, Serena Micheletti, Anna Molinaro, Alessandra Franzoni, Andrea Rossi, Francesco Semeraro, Lotfi B. Merabet, Elisa Fazzi
A Longitudinal Study of Visual Development
Cerebral, or cortical, visual impairment (CVI) is now the most common cause of childhood visual impairment. Unlike eye conditions such as cataracts or retinal disease, CVI comes from how the brain processes visual information. The eyes may be healthy, but the brain struggles to make sense of what they see. This is especially common in children with cerebral palsy (CP), where early brain injury affects movement, sensation, and often vision.
Historically, CVI has been described as a “permanent” condition, which may imply limited potential for change. However, clinical observations suggest that some visual skills can improve over time, especially during early childhood when the brain is still developing. Prior studies have hinted at improvement in specific functions such as visual acuity or eye movements, but most were cross-sectional—comparing different children of different ages rather than following the same children over time.
This study addresses a critical gap by longitudinally tracking children with CP and CVI from infancy into school age. By doing so, it aims to clarify which visual functions remain stable, which improve, which worsen, and which early signs predict later cognitive visual difficulties.
Main Research Question
The researchers aimed to answer two key questions:
1 How do different aspects of vision change over time in children with CP and CVI?
2 Which early visual difficulties are linked to later problems with cognitive visual disorders (e.g. problems with visuo-motor skills and visual perception)?
In everyday terms, the study asked: What improves, what doesn’t, and what early signs help us predict future challenges?
Methodology
The study followed 51 children with cerebral palsy and confirmed CVI over several years. Each child received detailed visual assessments at three stages:
- Infancy (6–35 months)
- Preschool age (3–5 years)
- School age (6 years and older)
At each stage, clinicians evaluated:
- Ocular structure and alignment, including refractive errors (glasses prescriptions), optic nerve appearance, and eye misalignment (strabismus)
- Eye movement control, such as fixation (holding gaze), smooth pursuit or tracking, and quick eye shifts (saccades)
- Basic visual function, including visual acuity, contrast sensitivity, and visual fields
Once children reached school age, some were able to complete tests of cognitive visual skills, such as recognizing objects, understanding visual information, and coordinating vision with movement.
An easy way to picture this design is to imagine a long-term growth chart for vision, rather than a single snapshot in time.
Image Description: A smiling boy wearing glasses lounges inside a playground tunnel.
Key Findings
CVI Remained Present, but Its Impact Changed
Every child met criteria for CVI at every age. However, the way CVI showed up changed over time. This confirms that CVI is lifelong, but not fixed or unchanging.
Ocular Structure and Alignment: Mostly Stable or Slowly Worsening
Refractive errors—especially astigmatism—were very common and stayed fairly stable. However, changes in the optic nerve (such as pallor or cupping) became more noticeable as children grew older. These changes may reflect delayed effects or recognition of early brain injury rather than new damage.
Eye alignment problems (strabismus) also became more frequent over time, particularly outward drifting of the eyes. Importantly, these changes often occurred gradually, reinforcing the need for ongoing eye care rather than one-time evaluations.
Eye Movement Skills: Improvement in Multiple Measures
Many eye movement skills improved significantly:
- Children became better at holding their gaze (fixation) steady
- Tracking or pursuit of moving objects became smoother
- Saccades had decreased latency (i.e. became faster to start), although the proportion of children with inaccurate saccades remained fairly stable
These improvements suggest that as the brain matures, it can learn to control eye movements better—even when early injury is present.
Basic Visual Functions: Often Better with Age
Visual acuity, contrast sensitivity, visual field defects improved for many children.
Cognitive Visual Difficulties Were Common
At school age, most children who could be tested showed cognitive visual disorders. These difficulties affect how children understand and use visual information, even if their basic visual functions improved.
There was a modest association between earlier eye movement problems and later cognitive visual difficulties.
Prognosis Worse in Preterm Children
Children born preterm were more likely to experience worsening of ocular structural changes and eye misalignment over time. They were also less likely to enjoy improvement in basic visual functions.
Significance: What This Means for CVI
CVI Is Lifelong, but Not Static
The study strongly supports a modern understanding of CVI: it does not disappear, but it can change significantly. Children may experience improvement in visual function and eye movements, especially in early childhood.
Early Eye Movement Issues May Have Prognostic Significance
Early, detailed eye movement assessment is important, and may in future be facilitated by objective techniques such as eye tracking.
Conclusions
This longitudinal study demonstrates that while cerebral, or cortical, visual impairment (CVI) in children with cerebral palsy is a lasting diagnosis, its manifestations evolve throughout development. Oculomotor and basic visual functions may improve substantially, whereas certain aspects of eye anatomy or alignment may worsen. Early oculomotor dysfunction may be predictive of later problems with cognitive visual skills, such as using vision to guide movement.
The findings support proactive, longitudinal monitoring and future research to determine whether early, targeted intervention can optimize visual and developmental outcomes.
Key Takeaways for Parents and Educators
- CVI is lifelong, but children’s visual abilities can and often do improve
- Eye movement skills are especially important for later learning
- Ongoing monitoring is essential—vision can change over time
- Educational support should focus on how a child uses vision, not just how well they see
Galli, J., Loi, E., Calza, S., Micheletti, S., Molinaro, A., Franzoni, A., Rossi, A., Semeraro, F., Merabet, L. B., & Fazzi, E. (2025). Natural history of cerebral visual impairment in children with cerebral palsy. Developmental medicine and child neurology, 67(4), 486–495. https://doi.org/10.1111/dmcn.16096