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Updated: Sep 25, 2026

An Automated Method for Assessing Visual Acuity in Infants and Toddlers Using an Eye-Tracking System
Published on: March 17, 2023
Practical Comparison of a Newly Developed Software-Based Visual Acuity Test and Photoscreening in Japanese Preschool
Yumiko Yamamoto1,2, Timur Bakhriddinov3, Hideyuki Sakaki4
1Yamamoto Heart and Eye Clinic, 3-1-41, Eriaecho, Nankoku 7830024, Kochi, Japan.
Background:
Early detection of vision problems in young children is crucial, as they may lead to lifelong disabilities such as amblyopia and strabismus. However, conducting visual acuity (VA) evaluations in this age group is challenging. We developed novel VA testing software tailored for young children with engaging animal images and sound effects to encourage participation.
Methods:
A total of 414 children aged three to five years were included in the study. Each child underwent evaluation using both the newly developed VA testing software and the Spot Vision Screener (SVS, Welch Allyn, USA; software Ver. B), a portable autorefractor. Statistical analysis was performed to explore the complementary roles of VA and refractive error measurements in identifying vision problems.
Results:
Among the 414 children, 407 (98.3%) successfully completed the VA test using the new software. Bilateral decimal VA of 0.8 (LogMAR 0.1) or higher was observed in 383 of the 407 children (94.1%). Of the 24 children with VA < 0.8, 7 (29.2%) were already under ophthalmological follow-up, while 17 (70.8%) were newly identified as having possible visual developmental issues. SVS detected refractive errors in 21 out of 407 children (5.2%). However, 14 of the 24 children (58.3%) with VA < 0.8 showed no refractive error on SVS evaluation.
Conclusions:
Assessment of both VA and refractive error provides complementary information for identifying potential vision impairment in young children. Practical VA testing is particularly important, as the SVS may not detect a substantial proportion of children with possible VA deficiency. These findings support the usefulness of child-friendly VA assessment tools in preschool vision screening.

