Changes In Binocular Visual Function Following Binocular Visual Training Using Digital Devices

Recently, digital therapeutic devices utilizing digital media technology have been rapidly growing in the healthcare sector. In the fields of ophthalmology and optometry, multimedia-based digital visual function training content has emerged, aimed at improving ocular muscle-related visual functions. However, much of this content is predominantly focused on entertainment and gaming, lacking a systematic structure, scientific validation, and sufficient clinical research. Recently, a program utilizing digital devices to improve ocular muscle-related visual functions has been patented and released. Therefore, this study aimed to scientifically observe changes in binocular visual function following visual training using this digital program. 

In this study, refractive errors were fully corrected using an autorefractor-keratometer (HRK-8000A, Huvitz, Korea) and a phoropter (CDR-3100, Huvitz, Korea). To assess static visual acuity, measurements were taken at a distance of 20 feet using a Snellen chart. After the complete correction of refractive errors, participants underwent a digital visual function training program developed by the authors (Korean Patent Application No. 10-2024-0166311) twice a week for 30 minutes each session. 

The study involved 55 healthy adult participants (26 males, 29 females), selected based on the absence of systemic or ocular diseases, no surgical history, and no strabismus (exophoria ≤ 6 prism diopters). A digital visual training program, developed as a game based on Unreal Engine (Korean Patent Application No. 10-2024-0166311), was used to enhance visual functions. Each participant completed 30 minutes of training by viewing a monitor with the program, after which binocular visual function was assessed. Post-training, visual acuity and refractive error were measured using traditional optometric methods, and horizontal vergence (Vongrafe method), PRC and NRC tests, and accommodation and accommodative facility tests were conducted.

The corrected visual acuity (CDVA) before and after digital visual function training was 0.0086 and 0.0043 logMAR, respectively, and no statistically significant difference was observed. However, the near point of accommodation improved from 10.08±1.40 cm to 8.12±0.93 cm, indicating enhanced accommodative power. The accommodative facility test showed a slight increase in the number of successful fusional convergence events from 10.75±0.40 to 11.22±0.89 per minute, suggesting improved ease in achieving clear focus. Additionally, the horizontal vergence test revealed a significant reduction in exophoria prism values, from 3.42±3.67∆ (exo.) to 1.13±0.95 (exo.) (p<0.05). 

Training with the digital visual function gaming program provided participants with the advantage of increasing engagement and immersion, allowing them to focus on the training more effectively. While no changes were observed in static visual acuity, participants exhibited a reduction in exophoria and improvements in both accommodative power and accommodative facility. These results suggest that the visual function training gaming software may be effective in reducing exophoria diopter and enhancing the overall accommodative abilities of the ocular muscles. However, to scientifically validate these findings, further studies involving larger sample sizes, diverse age groups, and long-term experimental verification are needed.