CONTINUOUS-WAVE ND-YAG LASER PHOTOCOAGULATION IN PROLIFERATIVE DIABETIC-RETINOPATHY

Aims-The therapeutic efficacy of the continuous wave (CW) Nd:YAG laser (working in the free running mode) was investigated in proliferative diabetic retinopathy (PDR) comparing it with a conventional laser sour ce such as the krypton laser. Methods-Twenty four eyes of 12 patients affected with bilateral PDR were included and divided in two groups. T he right eyes were treated with a red krypton laser and the left eyes with a CW Nd:YAG laser. Results-Three months after krypton photocoagul ation 10 eyes showed a reduction or a complete regression of PDR and t wo eyes were unchanged. In the CW Nd:YAG laser group no eyes showed an y regression of new vessels, in seven eyes the angiographic features w ere unchanged, and in five eyes they worsened. All the eyes of the sec ond group underwent retreatment with the krypton laser after 3 or 6 mo nths. After a mean follow up of 13 months all eyes in the krypton grou p showed a reduction or complete regression of PDR; in the retreated g roup 10 eyes improved and two were unchanged. Conclusions-The statisti cal analysis showed a highly significant difference (p=0.001) between krypton and CW Nd:YAG laser which indicated the lack of efficacy of th e latter in the treatment of PDR. Tn the krypton laser group no signif icant difference (p=0.05) after the retreatment was found confirming t he efficacy of this treatment.