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Should we add visual acuity ratios to referral criteria for potential cerebral visual impairment?
Ymie J van der Zee1, Peter Stiers2, Heleen M Evenhuis3
1Intellectual Disability Medicine, Department of General Practice, Erasmus University Medical Center, Rotterdam, The Netherlands; Royal Dutch Visio, Dutch Centre of Excellence for Visually Impaired and Blind People, The Netherlands.
Insights
Assessing visual acuity ratios can help identify children at risk of cerebral visual impairment. Youth health care professionals should use subnormal visual acuity screening, while ophthalmologists and low vision experts should add the crowding ratio for better diagnosis.
Area of Science:
- Ophthalmology
- Pediatric Neurology
- Developmental Pediatrics
Background:
- Cerebral visual impairment (CVI) in children presents diagnostic challenges, often co-occurring with other visual issues.
- Differentiating CVI from ocular abnormalities requires specific diagnostic tools beyond standard visual acuity tests.
Purpose of the Study:
- To evaluate if visual acuity ratios improve the identification of children with subnormal visual acuity who are at risk for CVI.
- To compare the effectiveness of different visual assessment methods for various diagnostic groups.
Main Methods:
- An exploratory study involving 107 children (60 typically developing, 21 with ocular abnormalities, 26 with suspected brain damage) aged 5-7 years.
- Assessment included visual acuity, crowding ratio, and ratios between grating acuity (Teller Acuity Cards-II) and optotype acuity (Cambridge Crowding Cards).
- Sensitivities and specificities were calculated for youth health care professionals and for ophthalmologists/low vision experts.
Main Results:
- For youth health care professionals, subnormal visual acuity demonstrated the highest sensitivity (76%) and specificity (70%).
- For ophthalmologists and low vision experts, the crowding ratio yielded the best sensitivity (67%) and specificity (79-86%).
Conclusions:
- Youth health care professionals should continue using subnormal visual acuity for initial screening.
- Ophthalmologists and low vision experts should incorporate the crowding ratio into routine diagnostics to better distinguish CVI risk from ocular pathology.
Purpose:
To determine whether the assessment of visual acuity ratios might improve the referral of children with (sub)normal visual acuity but at risk of cerebral visual impairment.
Methods:
In an exploratory study, we assessed visual acuity, crowding ratio and the ratios between grating acuity (Teller Acuity Cards-II) and optotype acuity (Cambridge Crowding Cards) in 60 typically developing school children (mean age 5y8m±1y1m), 21 children with ocular abnormalities only (5y7m±1y9m) and 26 children with (suspected) brain damage (5y7m±1y11m). Sensitivities and specificities were calculated for targets and controls from the perspective of different groups of diagnosticians: youth health care professionals (target: children with any visual abnormalities), ophthalmologists and low vision experts (target: children at risk of cerebral visual impairment).
Results:
For youth health care professionals subnormal visual acuity had the best sensitivity (76%) and specificity (70%). For ophthalmologists and low vision experts the crowding ratio had the best sensitivity (67%) and specificity (79 and 86%).
Conclusion:
Youth health care professionals best continue applying subnormal visual acuity for screening, whereas ophthalmologists and low vision experts best add the crowding ratio to their routine diagnostics, to distinguish children at risk of visual impairment in the context of brain damage from children with ocular pathology only.
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