Abstract
INTRODUCTION: Visual acuity (VA) is typically measured using stationary optotypes, though real-world visual experiences involve dynamic targets. The Dyop (dynamic optotype) VA test is a computerized motion perception assessment designed to simulate daily visual experiences. With the rise of telemedicine, this study examined the feasibility and agreement between virtual online VA testing using Dyop compared to standard LogMAR optotypes in non-presbyopic and presbyopic participants. METHODS: After an initial online Zoom(®) meeting verifying inclusion criteria and technical feasibility, participants accessed the examiner's computer using the "Anydesk" application enabling them to view the "Chart 2020" program. Monocular right eye VA was measured three consecutive times using Dyop and LogMAR optotypes in a counter-balanced design. Participants aged 18-39 yrs were considered non-presbyopic, and those 40-60 yrs were considered presbyopic. VA measurements were analyzed using the Mann-Whitney U-test, Spearman correlation coefficients, intraclass correlation coefficients (ICC), and non-parametric Bland-Altman analysis, which examined median differences and limits of agreement (LoA). RESULTS: Of the 110 participants, (70% females, mean age: 32.5 ± 13.0, range: 18-60), 73 (66%) were considered non-presbyopic (mean age: 24.1 ± 4.9, range: 18-39), and 37 (34%) were presbyopic (mean age: 49.0 ± 6.4, range: 40-60). The mean VA measured with the Dyop and LogMAR charts for the entire cohort (0.09 and 0.08), for the non-presbyopic (0.09 and 0.07) and the presbyopic (0.10 and 0.09) sub-groups was significantly positively correlated (r = 0.80, p < 0.001, r = 0.82, p < 0.001 and r = 0.72, p < 0.001, respectively), with a small mean difference (-0.01 ± 0.08, -0.02 ± 0.08, -0.01 ± 0.09 log units), for the entire cohort, the non-presbyopic, and the presbyopic, respectively. There were no significant differences between the two tests for the whole cohort (p = 0.80), for group 1 (p = 0.98) and for group 2 (p = 0.62). CONCLUSION: This study demonstrated the feasibility of online VA measurements and that online VA measurements using Dyop and LogMAR optotypes are interchangeable in healthy non-presbyopic and presbyopic participants.