A virtual-reality-based asynchronous dichoptic treatment for anisometropic amblyopia: A retrospective pilot clinical trial

PURPOSE: To assess the safety and effectiveness of virtual reality (VR) head-mounted display-based asynchronous binocular visual stimulation for the treatment of children with anisometropic amblyopia. METHODS: This was a randomized clinical trial. A total of 40 children 4-9 years of age whose best-corrected visual acuity (VA) in the amblyopic eye (AE) before treatment was between 0.2 and 1.0 logMAR (logarithm of the minimum angle of resolution in minutes of arc) were randomly assigned to receive occlusion only or occlusion + VR. Children in the VR-only group were not randomly assigned to this group. INTERVENTIONS: Children in the control group were from the same cohort as those in the preceding study and received daily occlusion-only treatment. Children in the occlusion + VR group received daily occlusion and asynchronous visual stimulation. Children in the VR-only group received only asynchronous visual stimulation. Intention-to-treat, per-protocol, and as-treated analyses were performed to determine the outcomes of this clinical trial. RESULTS: Compared with the occlusion and occlusion + VR groups, the VR-only treatment group met the VA criterion for successful treatment (VA improvement ≥ 0.3 logMAR). These results suggest that the performance of the VR-only treatment was superior to that of the occlusion and occlusion + VR treatments. The benefits of asynchronous conditioning were maintained for at least one year. CONCLUSIONS: This study suggests that VR-only treatment is safe and effective. It can produce substantial and persistent improvements in VA. A larger-sample, double-blind, randomized controlled clinical trial is warranted to confirm the effects of binocular asynchronous visual treatment for amblyopia. TRIAL REGISTRATION: ChiCTR2200055848.