INDIRECT SCATTER LASER PHOTOCOAGULATION TO SUBFOVEAL CHOROIDAL NEOVASCULARIZATION IN AGE-RELATED MACULAR DEGENERATION

Background: Occult choroidal neovascularization (CNV)I poorly defined on fluorescein angiography, is present in the majority of patients wit h exudative complications of age-related macular degeneration. For pat ients who present with this type of subfoveal CNV but who have useful visual acuity, no form of treatment is of proven benefit. Accordingly, a pilot randomized trial of indirect laser treatment was performed. T he rationale of this treatment was to inhibit the CNV through laser-in duced effects on the retinal pigment epithelium. Methods: Patients wit h occult subfoveal CNV without retinal pigment epithelial detachment a nd with visual acuity of 20/200 or better were randomized to treatment or control groups. A grid of laser burns was applied to the macula be yond the area of serous retinal detachment and of angiographically def ined occult CNV. Results: After an average follow-up of 38 months, the re was no difference in mean final visual acuity (0.12 treated, 0.14 c ontrol) or clinical outcome between treated and untreated groups. Fluo rescein angiography showed gradual enlargement in the occult CNV in 58 % of eyes in both groups. A decrease in visual acuity to worse than 20 /200 (54% of treated, 50% of control eyes) was associated with ingrowt h of well-delineated CNV (6 treated, 7 control eyes) or progression to a fibroglial or atrophic scar (11 treated, 8 control eyes). Conclusio ns: No benefit was demonstrated for scatter photocoagulation of the ma cula in patients with age-related macular degeneration and occult subf oveal CNV with initially good visual acuity. There were, however, no c omplications related to treatment.