Emerging therapies for improving stereoacuity in amblyopia. A systematic review and meta-analysis

Emerging treatments, including virtual reality (VR)-based therapies, video games, and movies, have been proposed to enhance stereoacuity in individuals with binocular vision disorders such as amblyopia and strabismus. However, their comparative effectiveness remains uncertain. This systematic review and meta-analysis aimed to evaluate the effectiveness of these emerging treatments in improving stereoacuity through within-group analyses, and to compare their outcomes with occlusion, in studies with direct group comparisons. We conducted comprehensive literature searches in PubMed, MEDLINE, Cochrane Library, Scopus, and Web of Science. Eligible studies included randomized controlled trials, cohort studies, and case-control studies reporting stereoacuity outcomes. The primary outcome was the change in stereoacuity (log arcsec). A random-effects meta-analysis, subgroup comparisons, and meta-regressions were performed. Twenty-six studies were included. The pooled mean improvement in stereoacuity was 0.26 log arcsec, i.e. a factor of 1.82 (95% CI: 0.19-0.33). Emerging treatments yielded significant within-group improvements, with no significant difference compared to occlusion therapy. VR-based interventions did not show statistically significant advantages over non-VR binocular treatments. Movies showed slightly greater gains than video games, but differences were not significant after correction. In regression analyses, no predictors remained significant after Bonferroni correction. Heterogeneity was moderate, reflecting variability across studies. In conclusion, emerging therapies demonstrate measurable benefits in enhancing stereoacuity. However, they have not consistently outperformed occlusion.