Abstract: Objective To investigate the long-term effectiveness of virtual reality-based vision therapy for convergence insufficiency,by evaluating the binocular visual function and subjective symptoms before and after vision therapy. Methods 36 participants with convergence insufficiency were enrolled. The participants were randomly allocated to virtual reality-based vision therapy and office-based vergence/accommodative therapy(OBVAT)groups. The duration of the training was 1 hour per week for 12 weeks. Binocular visual functions and subjective questionnaires.(Convergence insufficiency symptom survey, CISS)were completed before the training, after the 6th and 12th weeks of training, and 6 months after the vision therapy. A two-tailed t-test was used to assess differences between the two groups at baseline, and a two-factor repeated measures ANOVA was used to assess differences between the two groups before and after training. Results After 12 weeks of treatment for CI, significant improvements were found for near exophoria, near point of convergence, positive fusional vergence, and CISS score in both the VR and OBVAT(P<0.001)groups. No statistically significant difference was found between the results at the 6 months after training and the 12th week of training(P>0.05). No statistically significant difference was found in the improvements between the two groups(P>0.05). Conclusion Virtual reality-based vision therapy significantly improved binocular vision function and symptoms in young adults with CI, and the effect can be maintained for 6 months after the end of training. The efficacy of VR was not significantly different from that of OBVAT.

Key words: Virtual reality-based, Vision therapy, Convergence insufficiency, Long-term effectiveness