A Novel Test of Dynamic Visual Function: Comparison Between Presbyopic and Non-Presbyopic Individuals
Bingqing Sun, Yuhao Ye, Xingtao Zhou, Ye XuBackground/Objectives: Given the limited evidence on multi-distance visual function assessment in presbyopia, this study aimed to compare dynamic binocular visual function between presbyopic and non-presbyopic (NP) participants at different distances, and to further evaluate the effects of additional power (ADD) on dynamic sharpness discrimination, binocular integration, and dynamic stereopsis in presbyopic participants. Methods: A total of 54 presbyopic and 77 NP participants were tested at 0.4 m, 0.7 m, 1 m, and 3 m using a dichoptic rotating ring system with red-blue anaglyph glasses. Presbyopia was classified as low (LP, ADD < 1.5D) or high (HP, ADD ≥ 1.5D). Tests included dynamic sharpness discrimination, binocular integration, and stereopsis. To account for potential confounders, generalized linear models (GLM) were applied with sex, eye laterality, age, ADD, spherical equivalent (SE), and group as covariates, allowing comparison of visual function outcomes across different viewing distances between NP and ADD-stratified presbyopic groups. Results: There was no statistically significant difference in the passing rates of dynamic sharpness discrimination test between the presbyopic and NP groups (all p > 0.05). At 0.4 m, 0.7 m, and 1 m, the presbyopic group showed significantly lower passing rates in the binocular integration test compared with the NP group (all p < 0.05), while no significant difference was observed at 3 m (p = 0.051). Furthermore, the passing rates for binocular integration test at all distances were significantly lower in the HP group than those in both the NP and LP groups (all p < 0.05). GLM analysis indicated that both SE and age were potential confounders in the comparison of binocular integration between presbyopic and NP groups (both p < 0.05). There were no significant differences in the passing rates of binocular dynamic stereopsis test at any distance between the NP and presbyopic groups, or between the LP and HP groups (all p > 0.05). Conclusions: This novel dynamic testing method revealed ADD-dependent impairment of binocular integration at near-to-intermediate distances in patients with presbyopia.