Panretinal photocoagulation in diabetic retinopathy: argon versus dye laser coagulation

The range of wavelengths used in ophthalmic photocoagulation treatment has been greatly enlarged by the development of the dye laser. To investigate the efficacy and possible side effects of orange dye laser light in the treatment of diabetic retinopathy, we performed a prospective, controlled clinical study comparing argon blue-green and orange dye laser light. In 14 patients with diabetic retinopathy of equal severity in both eyes one eye was randomly assigned to either blue-green argon (488 and 514.5 nm) or orange dye (600 nm) panretinal laser treatment. The total coagulated area was the same in both eyes. Subjective parameters (visual acuity, perimetry, color vision) as well as objective functions (electroretinography, electro-oculography) and the clinical course were studied preoperatively and then postoperatively over a period of 6 months. Dye laser coagulation proved as effective and safe as blue-green argon laser coagulation in the panretinal treatment of diabetic retinopathy. No significant differences in postoperative retinal function were detected. However, orange laser coagulation proved significantly more painful than blue-green argon laser treatment (P = 0.002).