Abstract

AIM To investigate the effect of prophylactic laser treatment on drusen area and incidence of exudative lesions in patients with soft drusen maculopathy.

METHODS In a prospective study, patients with early age related maculopathy (ARM) and good visual acuity were randomised to laser treatment or to a control group. Each group consisted of two subgroups: a fellow eye group and a bilateral drusen group. At 3 years, 36 of 38 enrolled patients remained in the study. Photocoagulation was performed with an argon green laser, approximately 100 mild laser burns being placed on and between the drusen in a perifoveal temporal horseshoe-shaped area. Both cases and controls were subjected to fundus colour photographs and fluorescein angiograms at regular intervals, and the drusen area was calculated in both photographs and angiograms. At baseline, there were no significant differences (p>0.3–0.8) in drusen area between the groups.

RESULTS In the treatment group, mean drusen area decreased significantly in the fundus photographs as well as in the angiograms (p<0.001). Visual acuity and colour contrast sensitivity (CCS) did not change significantly. All these results are valid also for the subgroups. In the control group, however, mean drusen area increased significantly (p<0.001). Mean visual acuity decreased significantly (p<0.01) as did the colour contrast sensitivity along the tritan axis (p=0.02). For the fellow eye control group (n=7), the increase in drusen area in fundus photographs and the decrease in CCS along the tritan axis were not statistically significant (p=0.57 and p=0.37, respectively). Furthermore, at 3 years, five patients in the control group showed exudative lesions (1/7 in the fellow eye group and 4/12 in the bilateral drusen group), whereas no such complications occurred in the treatment group. One patient developed a small atrophy, however. Thus, there is now a significant difference (p=0.047), however with a large 95% confidence interval, 0.06–0.46, regarding exudative complications between the treated group and the control group in our small patient material.

CONCLUSION Perifoveal mild laser treatment causes a reduction in drusen area in patients with soft drusen maculopathy and may lower the incidence of exudative lesions.