Comparative Effects of Monocular and Stereopsis Training on Visual Acuity and Stereoacuity in Children With Amblyopia

Abstract

Purpose To evaluate changes in visual acuity (VA) and stereoacuity in children with amblyopia following monocular or stereopsis training delivered alongside standard clinical care and to examine factors associated with training-related improvements in visual outcomes. Methods Forty-three children with amblyopia (7.3–14.8 years; 37 anisometropic, five strabismic, and one mixed) completed approximately 29 sessions of either monocular training (grating acuity or motion discrimination targeting the amblyopic eye, n = 23) or binocular stereopsis training (dichoptic disparity discrimination, n = 20). All participants continued standard clinical management, including optical correction and prescribed patching. Pre- and post-training assessments included amblyopic-eye VA, interocular acuity difference (IOD), and Randot stereoacuity. Results Both training protocols produced significant task-specific learning. Amblyopic-eye VA improved significantly in both groups, with no evidence of differential effects between training approaches. Stereoacuity also improved in both groups, with significantly greater gains following stereopsis training than monocular training. Exploratory analyses indicated that poorer baseline amblyopic-eye VA was associated with larger VA gains; however, this association did not survive correction for multiple comparisons. Stereoacuity improvement was not significantly associated with baseline VA, IOD, age, or changes in VA. Conclusions Visual training combined with standard clinical care improved amblyopic-eye VA and stereoacuity in children with amblyopia. Although both training approaches yielded comparable gains in VA, stereopsis training produced larger improvements in stereoacuity, supporting its potential role in addressing residual binocular deficits after conventional treatment.