The rationale of argon green laser photocoagulation for diabetic maculopathy.

Eighty-four patients of bilateral diabetic retinopathy were divided into 2 groups: Group I comprised of 60 patients (mean age 46 yrs) having non-proliferative diabetic retinopathy with maculopathy (total no. of eyes = 120). Group II consisted of 24 patients (mean age 49.1 yrs) with proliferative diabetic retinopathy with maculopathy (total no. of eyes under study = 48). One eye of each patient in group I was treated as a control and the other was subjected to focal laser therapy. While 48/60 control Group I eyes (80%) had 6/24 vision at the outset, at one year follow-up only 39/60 cases (65%) had 6/24 vision. Diabetic maculopathy persisted in all the 60 control eyes at one year. In contrast, 44/60 eyes (73%) subjected to focal laser therapy in Group I, had 6/24 vision at outset but one year later, 49/60 eyes (81%) had 6/24 vision. Maculopathy completely regressed in 48/60 eyes (80%). The 48 eyes of Group II patients were subjected to focal and scatter laser therapy. 20/48 eyes (41.6%) had 6/24 vision prior to treatment but one year after treatment, 25/48 eyes (52%) had 6/24 vision. Neovascularization and macular edema regressed after one year in 42/48 eyes (87.1%) and only 4/48 eyes (8.3%) developed localized vitreous hemorrhage. Laser therapy in Group I improved visual acuity by reducing macular edema. In Group II, it improved the vision and reduced the risk of vitreous hemorrhage, detachment and glaucoma.