Prophylactic laser treatment of soft drusen maculopathy: a prospective, randomized Nordic study

Abstract

This study aimed to investigate whether mild laser treatment of soft drusen maculopathy might reduce the incidence of choroidal neovascularization (CNV) and/or significantly reduce loss of visual acuity compared with outcomes in a control group. A total of 135 patients (mean age 70.4 years) were randomized into a treatment group of 67 subjects and a control group of 68 subjects. The treatment group was subdivided into a group of 54 subjects with bilateral soft drusen and a group of 13 subjects with unilateral soft drusen in the study eye and advanced AMD in the fellow eye. The control group was subdivided into a bilateral group of 54 subjects and a unilateral group of 14 subjects. Sub-threshold or barely visible laser spots were scattered on and between drusen in the posterior pole. Inclusion of patients was stopped prematurely as other studies did not show any benefit from the treatment. Mean follow-up time was 3.7 years. More CNVs developed in the treated group (4/54 eyes in the bilateral group, 3/13 eyes in the unilateral group; 7/67 eyes in total) than in the control group (3/54 eyes in the bilateral group, 2/14 eyes in the unilateral group; 5/68 eyes in total) but these differences were not statistically significant for either the bilateral or unilateral groups (p = 0.20-0.32). No CNV developed in the bilateral treated group before 4 years of follow-up. Visual acuity was significantly reduced from baseline to the last follow-up in all groups (p < 0.0001-0.02) except the unilateral control group (p = 0.08), but there were no significant differences between the treated and control groups for either the bilateral or unilateral groups (p = 0.17-0.97). Mild prophylactic laser treatment of soft drusen maculopathy was neither beneficial nor harmful and cannot be recommended.