Article Title: Vision In SyndrOmic Neurodevelopmental disorders-15q (VISiON-15q) study: eye tracking to supplement clinical examination for detection of cerebral/cortical visual impairment in children with Angelman and Duplication of 15q Syndromes
Authors: Melinda Y. Chang, Sydney Jacobs, Katherine Granger, Anna Achenbach, Charlotte DiStefano, and Shafali S. Jeste
Introduction
Cerebral/cortical visual impairment (CVI) is a leading cause of visual impairment in children, yet it is often underdiagnosed, especially in children with developmental delays and genetic conditions. Identifying CVI in these children can be challenging because many traditional tests of visual perception require a child to understand instructions, name or match objects, point to answers, or maintain attention for an extended period. A child who cannot complete these tasks may have visual challenges that go unrecognized—or their difficulties may mistakenly be attributed entirely to their developmental disability.
The VISiON-15q study focused on children with Angelman syndrome (AS) and Duplication 15q (Dup15q) syndrome, two genetic conditions related to extra or missing copies of a section of chromosome 15q. Although previous research suggested that children with these conditions may be at increased risk for CVI, CVI had not been systematically studied in this population.
Main Research Question
The researchers asked whether eye tracking could help identify CVI that might be missed during a standard eye examination in children with 15q disorders. They also explored whether children with signs of CVI differed from other children with 15q disorders in their development, everyday functioning, and vision-related quality of life.
Methodology
The prospective study included 25 children between 12 months and 12 years of age with genetically confirmed Angelman or Dup15q syndrome. Each child underwent a comprehensive pediatric neuro-ophthalmologic examination. Vision was evaluated using several approaches because no single test works well for every child with developmental disabilities.
The researchers assessed visual acuity using the Visual Behavior Scale and, when children were able to participate, Teller acuity cards. Parents completed a questionnaire about behaviors that may indicate higher-level visual-processing difficulties (Higher Visual Function Question Inventory, HVFQI). Children were also evaluated with developmental assessments (Mullen Scales of Early Learning, MSEL), while parents completed measures of adaptive functioning (Vineland Adaptive Behavior Scales, 3rd edition) and vision-specific quality of life (Children’s Visual Function Questionnaire).
A key part of the study was eye tracking. Instead of asking children to explain what they saw or follow complicated directions, researchers showed them pictures and videos on a computer screen while a specialized camera recorded where they looked.
The researchers then used a technique called Saliency analysis of Eye Tracking for CVI (SET-CVI). This method uses a generative artificial intelligence (AI) model to measure how much attention a child gives to different visual features, including colors, brightness, faces, complexity, two-dimensional representations of depth, and still depictions of motion.
One way to think about SET-CVI is as a map of what naturally catches a child’s eye. Rather than simply asking, “Can this child see the picture?” it provides information about a more complicated question: “What information in this picture does the child’s brain notice and prioritize?”
Key Findings
The most important finding was how common CVI appeared to be. Fifteen of the 25 children (60%) were either diagnosed with CVI or considered to have a high suspicion of CVI. Eight were identified through clinical examination or Teller acuity testing, six through eye tracking, and one through the parent questionnaire.
Eye tracking added information that conventional testing did not. Six of the 15 children with diagnosed or highly suspected CVI—40% of that group—were identified through eye tracking alone. This was particularly important because many participants could not reliably complete traditional vision tests. More than half could not complete Teller acuity testing, whereas 72% of the children were able to complete eye tracking with adequate calibration.
Eye tracking also revealed differences in how children attended to visual information. Children with high suspicion for CVI tended to pay less attention to visual features requiring more complex processing and more attention to certain simpler features, such as colors and brightness. Their eye-tracking patterns were generally more similar to those of previously studied children with CVI than to typically developing children.
The differences extended beyond measures of vision. Children with diagnosed or highly suspected CVI had significantly lower scores in on the MSEL visual reception, fine motor, and verbal scales. They also had poorer vision-specific quality of life.
Image Description: Front page of the journal article. The article is open access.
Significance: What Does This Mean for CVI?
This study highlights an important challenge in diagnosing CVI: the children who may be most likely to have CVI can also be the least able to complete the tests commonly used to detect it.
Eye tracking offers a potential way around this barrier. It does not require a child to name an object, point to an answer, or explain what they see. The child mainly needs to look at images on a screen while the technology records their gaze. This makes eye tracking especially promising for children who are non-speaking, have intellectual disabilities, or have difficulty following testing instructions.
The findings also illustrate why good visual acuity does not necessarily mean that a child uses vision typically. Seeing a picture clearly and understanding a complex visual scene are different skills. This distinction has practical implications for parents and educators. A child who appears to “see” an object during an eye examination may still have difficulty finding that object in a cluttered classroom, interpreting a complex picture, recognizing important information in a busy scene, or deciding where to direct visual attention.
At the same time, the study does not establish eye tracking as a stand-alone diagnostic test for CVI. SET-CVI still requires validation in larger groups, and the researchers appropriately classified some children as having high suspicion rather than a definite diagnosis. The study was also relatively small, and children with Angelman and Dup15q syndromes were combined for much of the analysis.
Conclusions
The VISiON-15q study suggests that CVI may be common and underrecognized in children with Angelman and Dup15q syndromes. Sixty percent of the children studied had either diagnosed CVI or findings that raised high suspicion for it. Importantly, eye tracking identified several children whose visual difficulties were not detected through conventional testing.
These findings support using multiple approaches when evaluating vision in children with developmental disabilities. Clinical examination remains essential, but eye tracking may provide an additional window into how a child actually attends to and processes visual information.
Although this is a small study, the results are significant because the same eye tracking methods can potentially be applied to detect CVI in children with other neurogenetic and neurodevelopmental disorders. Future studies with larger and more diverse groups of children are needed to validate these techniques and determine how best to incorporate eye tracking into CVI assessments.
Key Takeaways
- CVI was common in this study: 60% of children with Angelman or Dup15q syndrome had diagnosed or highly suspected CVI.
- Eye tracking uncovered visual difficulties that standard testing missed. It was responsible for identifying 40% of the children in the CVI diagnosis/high-suspicion group.
- Eye tracking may be especially useful for children with developmental disabilities because it does not require language, motor response (other than eye movements), or ability to follow directions.
- CVI may be associated with greater developmental delays and worse quality of life. Children with diagnosed or highly suspected CVI had poorer vision-specific quality of life and lower scores in several developmental areas.
- Eye tracking is promising, but it is not yet a stand-alone CVI diagnostic test. Larger studies are needed to confirm these findings and establish how these tools should be used clinically. Multidisciplinary evaluation remains critical for CVI assessment.
Chang MY, Jacobs S, Granger K, Achenbach A, DiStefano C and Jeste SS (2026) Vision In SyndrOmic Neurodevelopmental disorders-15q (VISiON-15q) study: eye tracking to supplement clinical examination for detection of cerebral/cortical visual impairment in children with Angelman and Duplication of 15q Syndromes. Front. Hum. Neurosci. 20:1953706. doi: 10.3389/fnhum.2026.1953706