Vision training: comparing a novel virtual reality game of snakes with a conventional clinical therapy

Background: Vergence eye movements are the disconjugate movements of the two eyes, needed to accurately 'point' the eyes at an object of interest. Convergence insufficiency is the reduced ability to elicit and maintain the eyes in the accurate convergence position, and it affects about 5% of the population, often leading to visual symptoms such as diplopia (double vision), eye strain and headaches, especially during near tasks. The ability to converge and diverge accurately can be trained with vision training, but vision training activities are not standardized and they are often not complied with. Methods: We developed a novel virtual reality (VR) snake game and compared it with conventional anaglyph treatments in a randomized controlled trial on typical adults. Compliance was assessed by the time spent doing the prescribed vision training over a period of three weeks. Results: There was a statistically significant improvement of convergence ability in both the VR snake and anaglyph treatment groups, and no difference in compliance between the two groups. Conclusion: Virtual reality headsets may be used to train vergences in adults. Further work is required to determine its utility in people with convergence insufficiency who require training for longer than 3 weeks.