Straylight effects with aging and lens extraction

PURPOSE: To assess possible gains and losses in stray-light values among the population to consider straylight as added benefit of lens extraction. DESIGN: In this cross,sectional design, data from a multicenter study on visual function in automobile drivers were analyzed. METHODS: On both eyes of 2,422 subjects, visual acuity (logarithm of the minimum angle of resolution [logMAR] in steps of 0.02 log units), straylight on the retina (psychophysical compensation comparison method), and lens opacity (slit-lamp scoring using the Lens Opacities Classification System III [LOCS 111] system) were determined. Three groups were defined: 220 pseudophakic eyes, 3,182 non, cataractous eyes (average LOCS III score, < 1.5), and 134 cataractous eyes (average LOCS III score, > 3.0). RESULTS: Noncataractous straylight values increases strongly with age as: log(s) = constant + log(l + (age/65)(4)), doubling by the age of 65 years, and tripling by the age of 77 years. Population standard deviation around this age norm was approximately 0.10 log units. The cataract eyes (in this active driver group) had relatively mild straylight increase. In pseudophakia, straylight values may be very good, better even than in the noncataract group. Visual acuity and straylight were found to vary quite independently. CONCLUSIONS: Lens extraction holds promise not only to improve on the condition of the cataract eye, but also to improve on the age-normal eye. Lens extraction potentially reverses the strong age increase in straylight value, quite independently from visual acuity.