Long-term visual outcome in proliferative diabetic retinopathy patients after panretinal photocoagulation

There is the need for a long-term study on the visual outcome of panretinal photocoagulation (PRP) for proliferative diabetic retinopathy (PDR) patients.

We retrospectively reviewed the clinical course and visual results in 66 eyes of 59 patients with PDR who were followed-up for at least 10 years after argon or krypton laser PRP.

Thirty-nine eyes had stage B-II, whereas 8 eyes had stage B-III retinopathy. Stage B-IV and B-V retinopathy were seen in 15 and 4 eyes, respectively. Although active stages of diabetic retinopathy were encountered after 5 years, complete regression could be successfully attained after 10 years. Long-term visual prospects were promising for eyes with stage B-II DR; 28.2% still enjoyed 20/40 or better visual acuity by 5 years. Most cases had maintained the same visual acuity at 10 years. Eyes with stage B-III DR did not attain 20/40 vision by 10 years. Panretinal photocoagulation in cases with neovascularization of the optic nerve head was seen to be beneficial but limited, suggesting that such cases might benefit from maximal initial and supplemental PRP followed by vitrectomy and intraoperative endophotocoagulation when necessary. Although 20% of the eyes with stage B-IV and 25% of the eyes with stage B-V DR had 20/40 or better visual acuity, analyses of the visual change revealed that about half the eyes with stage B-IV and all eyes with stage B-V DR experienced a visual loss of two lines or more.

Progression of lens opacities, chronic macular edema, vitreous hemorrhage, macular traction, and neovascular glaucoma were the main causes of visual loss in this series. Panretinal photocoagulation for PDR provides good anatomical and visual outcome for 10 years or longer.