Clinical efficacy of navigated panretinal photocoagulation in proliferative diabetic retinopathy

Purpose To compare the clinical efficacy of navigated pattern and conventional slit-lamp pattern panretinal photocoagulation (PRP). Design Randomized clinical trial. Methods Seventy-four eyes with proliferative diabetic retinopathy (PDR) in need of PRP were randomly assigned to 1 of 4 groups: PRP conventional pattern 30 ms, 100 ms, navigated pattern 30 ms, 100 ms pulse. Navigated laser is a fundus camera-based photocoagulator with retinal eye tracking. Outcome variables included stability of visual acuity, regression or development of neovascularization and need for retreatment sessions and surgical intervention, pain perception, and procedure time. Results There was no change in visual acuity between pre- and post-treatment measurements among the study groups. Short pulse groups in total required 22 procedures compared to 12 procedures in long pulse groups (P <.05). A trend toward worse outcome using 30 ms pulse duration treatments is expressed by slightly increased relative risk of 1.3 compared to 100 ms groups. Only 2 eyes required vitreoretinal surgery for nonclearing vitreous hemorrhage, 1 in each 30 ms group; insignificantly different between study groups (P =.98). The pain score was lower with navigated laser as compared to conventional laser in both 30 ms groups (P =.1) and 100 ms groups, where it reached statistical significance (P =.02). Pain experience was significant (P <.001) between navigated 100 ms pattern and conventional single-spot 100 ms treatments. Conclusions This study demonstrates better clinical efficacy of 100 ms compared to 30 ms treatments using both conventional and navigated pattern lasers. The ability to use long-pulse-duration navigated pattern treatments broadens therapeutic options for PRP in proliferative diabetic retinopathy.