The Effects of Diffusive Blur on Snellen and Grating Acuity in Amblyopia

ABSTRACT

Amblyopia is a disturbance of spatial or form vision that develops early in life, usually in association with strabismus, anisometropia, high refractive errors and so on. It was reported that the visual functions obtained from the foveal region of an amblyopic eye resembled those obtained from the peripheral retina rather than central retina of a normal eye. We designed this experiment which examines the effects of diffusion blur on grating and Snellen acuity in normal and amblyopic eyes, using a liquid crystal window. We obtained the value of diffusion blur in 26 amblyopic eyes and then compared the result with that of normal eyes. The diffusion blur had a strong negative effect on both the Snellen and grating acuity but it had a more potent effect on grating acuity. Because there is a significant difference in the diffusion blur produced by an amblyopic eye and a normal eye at the same vision, there is a difference between visual function of amblyopic eyes and that of normal central retina.