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Updated: Jun 14, 2026
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An Automated Method for Assessing Visual Acuity in Infants and Toddlers Using an Eye-Tracking System
Published on: March 17, 2023
Amblyopia in astigmatic infants and toddlers
Velma Dobson1, Erin M Harvey, Candice E Clifford-Donaldson
1Department of Ophthalmology and Vision Science, The University of Arizona, Tucson, Arizona, USA.
Summary
Children with astigmatism show reduced visual acuity even in early childhood. This study found no evidence of meridional amblyopia (MA) before age three in these young children.
Area of Science:
- Ophthalmology
- Pediatric Optometry
- Visual Development
Background:
- Early detection of visual impairments is crucial for optimal outcomes.
- Astigmatism is a common refractive error affecting visual clarity.
- Understanding the impact of astigmatism on visual development in infants and toddlers is essential.
Purpose of the Study:
- To investigate the presence of reduced astigmatism-corrected acuity and meridional amblyopia (MA) in children under three years old with with-the-rule astigmatism.
Main Methods:
- 448 children aged 6 months to 2 years with with-the-rule astigmatism were studied.
- Astigmatism was measured using non-cycloplegic autorefraction.
- Astigmatism-corrected grating acuity for vertical and horizontal stimuli was assessed using the Teller Acuity Card procedure.
Main Results:
- Children with astigmatism exhibited significantly poorer astigmatism-corrected acuity for both vertical and horizontal gratings compared to non-astigmats.
- This reduction in acuity was observed across all age groups studied (6 months to <3 years).
- No significant difference in V-H grating acuity was found, indicating no evidence of MA.
Conclusions:
- Astigmatism negatively influences visual development from an early age, even before three years.
- The absence of meridional amblyopia suggests it may develop later or be less common in hyperopic astigmatism.
- Early astigmatism correction may be important for preventing long-term visual deficits.
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