Predictor of druen reduction after ubthrehold infrared (810 nm) diode laer macular grid photocoagulation for nonexudative age-related macular degeneration

PURPOE: To determine the predictor of druen reduction in eye with nonexudative age-related macular degeneration (ARMD) treated with ubthrehold infrared (810 nm) diode laer macular grid photocoagulation. Additionally, to determine the relationhip of laer-induced druen reduction and bet-corrected viual acuity (BCVA) 18 month after laer treatment. DEIGN: Randomized controlled clinical trial. METHOD: Fifty patient (100 eye) with bilateral nonexudative ARMD were enrolled at two center. One eye of each patient wa randomized to the obervation; the other eye wa treated with 48 ubthrehold (inviible end point) application of infrared (810 nm) diode laer in a macular grid pattern. The eye that received ubthrehold laer treatment were compared with the eye that received no treatment. The baeline fundu characteritic (number, ize, and ditribution of druen, a well a focal hyperpigmentation) from two macula area (central 1500 μ diameter, pericentral 1500 μ ring area) on tereo color photograph, the number of laer-induced leion, and the area of laer induced retinal pigment epithelial (RPE) leion on fluorecein angiography 3 month after treatment were tudied a predictor of major druen reduction (≥ 50% druen reduction from baeline) 18 month after laer treatment. BCVA at baeline and 18 month later wa compared in obervation eye and in laer-treated eye. REULT: Eighteen month after randomization, 24 (48%) of 50 eye treated with ubthrehold laer had major druen reduction compared with three (6%) of 50 obervation eye (P = .00001). At 3 month pot-treatment in laer-treated eye with major druen reduction, the mean number of laer-induced leion on fluorecein angiography wa 30.7 and the mean area of RPE change wa 0.81 mm2 compared with 14.8 laer-induced leion and 0.35 mm2 area of RPE change in eye without major druen reduction (P = .0001 and P = .0003, repectively). At baeline, fundu characteritic were not ignificantly different between obervation eye and laer-treated eye or between the major druen reduction group and the nonmajor druen reduction group. At 18 month after treatment, BCVA wa not ignificantly different in laer-treated eye and in obervation eye. CONCLUION: ubthrehold infrared (810 nm) diode laer macular grid photocoagulation in eye with nonexudative ARMD ignificantly reduced druen 18 month after laer treatment. Both the number of ubthrehold laer leion and the area of RPE change viible on fluorecein angiography 3 month after treatment appeared to be predictor for major druen reduction 18 month after treatment. However, it remain to be determined whether laer-induced druen reduction i beneficial for viual acuity or reduce the incidence of choroidal neovacularization (CNV) in eye with nonexudative ARMD.