The Effects of Argon Laser Photocoagulation in Diabetic Retinopathy

ABSTRACT

Diabetic retinopathy is said to be the 10% of cause of blindness added each year to the blindness registers in the world. The use of photocoagulaiton to treat proliferative diabetic retinopathy has gained widespread acceptance in ophthalmic practice since its introduction in 1959 by Meyer-Schwickerath, Neovascularization on the optic disk is a serious complication of diabetic retinopathy since it frequently leads to vitreous hemorrhage and blindness. The purpose of photocoagulation is thought to reduce the stimulus for the vessel formation so charicteristic of proliferative retinopathy. The technique of peripheral retinal ablation by photocoagulation involves production of many burns scattered over all but the central retina. Meyer-Schwickerath showed that regression could occur in newly formed vessels at retinal level even though treatment was remote from the lesion. This trial was initiated in May 1978 to attempt elimination of optic disk or retinal neovascularization in the diabetic retinopathy by peripheral retinal ablation or focal retinal ablation and to evaluate the effects of Argon laser photocoagulation on the course of the disease. In Kong's Eye Clinic I have treated the proliferative diabetic retinopathy by argon laser pan retinal photocoagulation(PRP) or focal retinal photocoagulation. I have found significant neovascular regressive changes in angiografic findings in four cases in which proliferative retinopathy was treated by Argon laser photocoagulation compared to the untreated angiografic findings. Follow-up study of treated patients will continue to allow long-term comparison between the pre and post photocoagulation treatment employed.