Impact of Cataract on Color Vision and Contrast Sensitivity: A Clinical Review

This clinical review examines current evidence on the effects of cataracts on color vision and contrast sensitivity (CS), the underlying optical mechanisms, and functional outcomes following cataract surgery. Evidence was synthesized from structured searches of the PubMed and Scopus databases, covering database inception to January 2026. Included studies quantitatively assessed how age-related cataract type or lens opacity density affects color vision, CS, and functional visual outcomes before and after standard phacoemulsification with posterior chamber intraocular lens implantation. Cataracts consistently impair color vision, most notably along the blue-yellow (tritan) axis, particularly in nuclear cataracts, likely because of selective short-wavelength light absorption by the yellowed crystalline lens. With increasing lens opacity density, additional red-green (protan) deficits may also occur. CS is reduced, particularly at intermediate spatial frequencies around 3-6 cycles per degree, likely in association with increased intraocular light scatter. These functional deficits may appear in early stages and worsen with disease progression. Cataract surgery generally results in rapid and clinically meaningful improvements in color discrimination, CS, glare tolerance, and vision-related quality of life. Overall, the reviewed evidence indicates that cataracts have a substantial impact on visual function beyond visual acuity and that assessment of color vision and CS provides important additional insight into cataract-related visual disability.