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Updated: Jul 16, 2025
Author Spotlight: An Automated Method for Assessing Visual Acuity in Infants and Toddlers Using an Eye-Tracking System
Published on: March 17, 2023
What we have learned from the Infant Aphakia Treatment Study: The 49th Annual Frank D. Costenbader Lecture
1Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, California.
Insights
Early cataract surgery and consistent optical correction can improve vision in children with unilateral congenital cataracts. The Infant Aphakia Treatment Study (IATS) compared contact lenses versus intraocular lenses (IOLs), finding both can yield good results but IOLs had more adverse events.
Area of Science:
- Ophthalmology
- Pediatric Ophthalmology
- Vision Science
Background:
- Unilateral congenital cataracts cause severe deprivation amblyopia with historically poor visual outcomes.
- Advances in infant brain plasticity and surgical techniques have improved outcomes for some patients.
Purpose of the Study:
- To provide empirical evidence on the optimal optical correction after cataract surgery in infants.
- To compare outcomes for infants left aphakic with contact lenses versus those receiving intraocular lens (IOL) implantation.
Main Methods:
- Infants were randomly assigned to either be left aphakic (contact lenses) or receive an IOL with spectacle correction.
- Key outcome measures included visual acuity and stereopsis.
Main Results:
- Good visual acuity and stereopsis were achievable in both treatment groups.
- Early surgery, consistent correction, and part-time patching were crucial for good outcomes.
- IOL implantation led to more adverse events, including visual axis opacification.
- Glaucoma-related adverse events occurred in 40% of eyes at 10-year follow-up, independent of IOL status.
Conclusions:
- Both aphakic correction with contact lenses and IOL implantation can lead to good visual outcomes in unilateral congenital cataracts.
- Careful management of optical correction and patching is essential.
- Further research is needed to improve outcomes for all affected children.
Abstract:
Unilateral congenital cataracts lead to deprivation amblyopia, which can be severe. Until the 1970s, they were believed to be always associated with poor visual outcomes. However, advances in our understanding of the plasticity of the infant brain and the development of better surgical techniques allowed good visual outcomes to be obtained in a few of these patients. The Infant Aphakia Treatment Study (IATS) was conducted to provide empirical evidence regarding the best type of optical correction to be used following surgical extraction of the cataract. Specifically, infants were randomly assigned to either be left aphakic and to wear contact lenses or an intraocular lens (IOL) was implanted and the residual refractive error was corrected with spectacles. The study found that good visual acuity and stereopsis could be achieved in some patients in both treatment groups. Early cataract surgery, consistent optical correction and part-time patching of the fellow eye are important elements needed to achieve good visual outcomes. However, excess patching of the fellow eye may interfere with the development of stereopsis. More adverse events occurred after IOL implantation, particularly visual axis opacification, compared with the infants who were left aphakic. Glaucoma-related adverse events occurred in 40% of eyes after a 10-year follow-up and were not associated with IOL implantation. Further research is needed to increase the percentage of children with unilateral congenital cataracts who achieve good visual outcomes.
