[Laser treatment for pre-proliferative and proliferative diabetic retinopathy]

105 cases of pre-proliferative and proliferative diabetic retinopathy were treated with argon laser panretinal photocoagulation mainly on the mid-periphery and posteriorly 1.5-2 DD from the optic disc. The posterior fundus, i.e. the area temporal to the optic disc between the superior and inferior temporal vascular arches and 1-2 DD temporal to the macula, was spared. The treatment was completed in 3-4 sessions of 300-800 shots each. Among 80 cases (138 eyes) followed up for over 1 year, 50.7% obtained good results, with visual acuity improved by 2 lines on Snellen's chart, resorption of retinal exudates and hemorrhages, and regression of microaneurysms and neovascularization; 39.7% showed middling effects, with visual acuity up or down by 1 line and the lesions of diabetic retinopathy still visible; and 10.1% deteriorated, with visual acuity drops of over 2 lines and fundus lesions worsened or obscured by vitreous bleeding. The causes of failure were discussed.