Laser-induced drusen reduction improves visual function at 1 year

Objective: To describe the relationship of laser-induced drusen reduction t o change in visual function at 1 year among patients enrolled in the Choroi dal Neovascularization Prevention Trial (CNVPT). Design: Comparison of groups with and without drusen reduction; follow-up o f a randomized controlled trial. Participants: Evaluations of drusen and visual acuity at baseline and at 1 year were performed for 351 eyes of the 432 eyes enrolled in the CNVPT Bila teral Drusen Study and Fellow Eye Study (81%). One hundred eighty-four eyes were assigned to observation, and 167 eyes were assigned to laser treatmen t. Eyes with conditions that precluded an analysis of drusen reduction, suc h as those that developed choroidal neovascularization (CNV) within the fir st year, are excluded from this analysis. Methods: Change in macular drusen between initial visit and after 1 year wa s assessed by side-by-side grading by evaluators masked to information on v isual function. Visual acuity, contrast threshold, and critical print size were measured by certified visual function examiners. Main Outcome Measures: Change in visual acuity is the primary outcome. Chan ge in contrast threshold and change in critical print size are secondary ou tcome measures. Results: Laser-treated eyes with 50% or more drusen reduction at 1 year had more 1- and 2-line increases in Visual acuity and less losses in visual ac uity compared with laser-treated eyes with less drusen reduction or with ob served eyes (P = 0.001), Similar improvements were noted for contrast thres hold but not critical print size at 1 year. Conclusions Laser-induced drusen reduction is associated with improved visu al acuity and contrast sensitivity in eyes at 1 year. Longer term effects o f laser-induced drusen reduction on visual function require additional obse rvation. The overall potential value of laser treatment in eyes with high-r isk drusen requires consideration of not only short-term effects on vision but also the effects of CNV and atrophy on vision.