Abstract
PURPOSE: Compare choroidal changes in ranibizumab versus panretinal photocoagulation (PRP)-treated eyes with proliferative diabetic retinopathy (PDR). METHODS: DRCR Retina Network Protocol S post hoc analysis evaluated optical coherence tomography change in choroidal thickness (subfoveal and 3mm superior and inferior to the fovea) through five years; choroidal vascularity index (CVI) was assessed at baseline and one year. Mixed linear models for choroidal change included adjustments for the baseline choroidal value and age. RESULTS: This study included 328 eyes (158 ranibizumab and 170 PRP) from 256 participants (88 ranibizumab and 95 PRP eyes at five years). Mean change in choroidal thickness from baseline to five years at the fovea was -12 µm in ranibizumab versus -8 µm in PRP (difference [95% confidence interval]: -4 [-18 to 10], P = 0.57), superior was -14 µm versus -19 µm (difference: 5 [-8 to 17], P = 0.45) and inferior was -26 µm versus -32 µm [difference: 5 (-9 to 20), P = 0.45]; change at all three points within the ranibizumab group, and the superior and inferior points for PRP, were statistically significant (P < .05). Mean change in CVI at one year was -0.02% in ranibizumab versus -0.95% in PRP (difference: 0.93 [-0.35 to 2.21], P = 0.14). CONCLUSIONS: In patients with PDR, treatment with ranibizumab versus PRP did not result in statistically significant differences in five-year choroidal thickness or one-year CVI change. Both groups had significant decreases in choroidal thickness at five years. TRANSLATIONAL RELEVANCE: Ranibizumab treatment for PDR did not statistically significantly affect choroidal thickness or vascularity differently than PRP.