Purpose: To investigate long-term enlargement of laser photocoagulation scars after treatment of choroidal new vessels (CNV) in age-related macular degeneration or myopic neovascular maculopathy. OBJECTS AND METHOD: Twenty-four eyes of 24 patients aged between 45 and 77 years were treated with laser photocoagulation for juxtafoveal or extrafoveal choroidal neovascularization in Yodogawa Christian Hospital. There was no recurrence in any of the eyes and the mean follow-up period was 31.0 +/- 13.7 (mean +/- standard deviation) months (13-60 months). The laser photocoagulation scar was measured with an image analyzer immediately and once a year after the treatment. We investigated the relationship between scar expansion rate and visual axis measured by A-mode ultrasonography.
Results: Expansion of the coagulation scars (atrophic creep) was observed in 19 eyes (79.2%). The coagulation scar expanded with the length of the period after treatment in most of the patients. The expansion rate was significantly correlated with the length of the eye at two years after treatment in all 24 eyes and even in 21 of the eyes without high myopia (p < 0.05). A decrease in visual acuity was observed in only one eye (4.2%). Remarkable pigmentation around the scar was found in three eyes of five that did not have atrophic creep.
Conclusion: Although atrophic creep occurs in approximately 80% of eyes after successful laser treatment, visual acuity deterioration is rarely encountered. The rate of expansion is significantly correlated with the axial length among the eyes both with and without high myopia. Heavy pigmentation around scars may be one sign which indicates a low expansion rate of atrophic creep.