Abstract
Purpose :
Virtual Reality (VR) is a technology that is used to compute and create a virtual world that is close to the real world. Recently, VR has been applied in metaverse, surgical support, and e-sports. The users experience the VR image through the head-mounted display (VRHMD) and correct their pupillary distance and refractive errors by adjusting the lens positions and adding optical lenses, respectively. However, Aniseikonia has not been compensated for using the VRHMD. Aniseikonia is the difference in image size perceived between both eyes from unequal magnification, and most of that is induced by anisometropia. We hypothesized that aniseikonia induces visual fatigue because excessive binocular fusion is required to maintain binocular vision. The aniseikonia can be created artificially using size lenses. Visual fatigue can be evaluated objectively and has high repeatability using the binocular fusion maintenance (BFM) test (Hirota et al., Transl Vis Sci Technol, 2018). This study evaluated the relationship between visual fatigue and the amount of aniseikonia using VRHMD.
Methods :
A total of 16 young adult volunteers (age [mean ± standard deviation], 21.5 ± 2.2 years) with aniseikonia < 1% using spatial aniseikonia test participated in this study. The VRHMD was used Meta Quest2 (Meta Platforms Inc.). Each subject performed under three conditions: Soft contact lens wear (control group), soft contact lens with size lens of 5% (5% group), and size lens of 10% (10% group). BFM was assessed by measuring the transmittance of liquid crystals placed in front of the subject’s non-dominant eye when binocular fusion was broken and the non-dominant eye shifted to a heterophoric. Each subject underwent the BFM test and subjective symptom questionnaire before and after a 30-minute visual task. The order of measurement for the control group, 5% group, and 10% group was randomized, and the measurements were performed at intervals of at least 24 hours.
Results :
The amount of aniseikonia was significantly and negatively correlated with BFM (R = 0.305, P = 0.035) and significantly and positively correlated with subjective eye symptom scores (R = 0.291, P = 0.045).
Conclusions :
These results suggest that aniseikonia induces objective and subjective visual fatigue in VRHMD use.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.