Development and Evaluation of a Dynamic Computerized Visual Acuity Test for Children and Adults

Abstract

Purpose : Previous studies have shown Tumbling E, Landolt C, or Snellen Exam charts to be effective in finding visual acuity thresholds for children, but they can be unappealing and sometimes challenging for children. Our aim was to develop and to evaluate a more innovative visual acuity test, which could be easily understood and engaging to ultimately use with children.

Methods : The Multi-Visual Acuity (MVA) test is a computer-generated test presenting simultaneously up to 8 Landolt “C” and “O” targets at 100% contrast using a modified constant stimulus method. The visual acuity measurements were conducted monocularly with the MVA and used the Tumbling E chart as a Gold Standard. To evaluate the MVA as a function of blurring, visual acuity was assessed for seven subjects (aged 26.43 ± 8.50 years) under 7 levels of blur ranging between 0 and +3 diopters (D). A second procedure was conducted with 28 subjects (aged 25.48 ± 5.5 years) who were tested in both tests, with a repetition of the measurement to evaluate reproducibility.

Results : All subjects performed both tests correctly. Linear regressions estimated for visual acuities in both tests as a function of blurring showed no significant difference for angle (p = 0.5153) but there was significant difference between the intersection with the axis (p=0.008). Visual acuities obtained in the larger sample of subjects with the MVA did not differ statistically between the two tests. Likewise, there was no significant difference between the results for each and its repetition (p = 0.2118).

Conclusions : The VAs measured with the MVA were confirmed by those obtained with the Tumbling E, the Gold Standard used, showing that the new test is able to offer a correct estimate of visual acuity. The new test might therefore be an effective alternative to those currently used in clinical examinations. Furthermore it provides an easily understood task with more simultaneous choices and no direction information required, a contemporary alternative means for visual acuity testing.

This is a 2020 ARVO Annual Meeting abstract.