Double-frequency Nd: YAG laser vs. argon-green laser in the treatment of proliferative diabetic retinopathy: Randomized study with long-term follow- up

Background and Objective: A randomized clinical trial using the argon- green (514 nm) and the double-frequency Nd:YAG (532 nm) lasers was carried out on 42 eyes with proliferative diabetic retinopathy (PDR), with the aim of assessing the long-term effects of double-frequency Nd:YAG panretinal photocoagulation (PRP). Materials and Methods: Twenty-one eyes were randomized to argon laser treatment (ALT) and 21 to double-frequency Nd:YAG laser treatment (NdLT). The mean follow-up was 28.90 months (± 6.13) in the ALT group and 29.57 months (± 5.17) in the NdLT group. Results: In the ALT group, 20 eyes (95.2%) showed regression of PDR and one eye (4.8%) enlargement of pre-existing new vessels. In the NdLT group, neovascularization regressed in 20 eyes (95.2%) and increased in one (4.8%). Conclusions: The long-term efficacy of double-frequency Nd: YAG laser PRP in the treatment of PDR thus appears to be similar to that of argon-green.