Prophylactic Laser Treatment Hastens Choroidal Neovascularization in Unilateral Age-Related Maculopathy: Final Results of the Drusen Laser Study

The Drusen Laser Study evaluated macular laser to prevent choroidal neovascularization (CNV) and vision loss in high-risk age-related maculopathy (ARM). Prospective, interventional, randomized, controlled clinical trial in five hospital centers. Patients in the unilateral group had neovascular ARM and drusen in the study eye. Study eyes were randomized to laser-treated or no-laser groups. For patients in the bilateral drusen group, eyes were randomized to right eye, laser or no laser; and left eye, alternative. Laser treatment comprised 12 argon spots. Outcome was best-corrected visual acuity and CNV signs, which were monitored for 3 years. In the unilateral group, vision loss occurred in 21 (28.8%) of 73 patients in laser vs 13 (19.7%) of 66 no-laser patients ( P = .214). Incidence of CNV was 27 (29.7%) of 91 in laser vs 15 (17.65%) of 85 no-laser patients ( P = .061). CNV onset was approximately 6 months earlier in laser-treated compared with no-laser patients ( P = .05). In the bilateral group, vision loss occurred in six (8.3%) of 72 laser-treated vs 10 (13.9%) of 72 fellow eyes ( P = .3877). CNV incidence was 12 (11.6%) of 103 in laser-treated vs seven (6.8%) of 103 fellow eyes ( P = .225). There was no difference in onset of CNV. Results do not support prophylactic laser of the fellow eye of patients with neovascular ARM. Its role in patients with bilateral drusen remains unclear.