EFFECTS OF ARGON (GREEN) LASER TREATMENT OF SOFT DRUSEN IN EARLY AGE-RELATED MACULOPATHY - A 6 MONTH PROSPECTIVE-STUDY

Aim-To evaluate whether perifoveal laser photocoagulation of soft drus en reduces the total area occupied by drusen. Method-In a prospective, randomised study, 20 patients (mean age 71.3 (SD 7.7) years) with ear ly age-related maculopathy (ARM) in the form of soft drusen and pigmen tary changes and with good visual acuity (0.94 (0.09)) were treated wi th argon green laser photocoagulation. Mild laser bums (200 mu m) were placed within a temporal horseshoe-shaped area, extending from a dist ance of no less than 500 mu m from the centre of the fovea to the vasc ular arcades. They were placed on the drusen and scattered over areas where no drusen were present. Fundus colour photography and fluorescei n angiography were performed at study entry as well as after 3 and 6 m onths. Nineteen age-matched patients (68.5 (6.2) years) with soft drus en maculopathy (visual acuity 0.95 (0.10)) were followed as a control group. Using a computer system, the area occupied by drusen was determ ined as a portion of the total area of a circle with a radius correspo nding to 1250 mu m in the fundus for the angiograms and 2500 mu m for the colour photographs, respectively. At study entry, the mean area oc cupied by drusen in the treatment group was not significantly (p>0.5-0 .7) different from that of the control group. Results-The mean drusen area of the angiograms and fundus colour photographs in the treated gr oup decreased significantly from 19.3% to (p=0.002) and from 7.84% to (p=0.005), respectively. In the untreated group, the mean area occupie d by drusen increased significantly from 17.4% to 20.4% (p=0 030) and from 8.33% to 9.23% (p=0.002), respectively. No significant changes in visual acuity (p>0.05-0.5) or in visual fields (p>0.05-0.3) occurred in either of the two groups during 6 months. Conclusion-The study sugg ests that the area occupied by soft drusen in patients with early ARM decreases after perifoveal laser photocoagulation but increases in an untreated control group.