Retinal Blood Flow after Intravitreal Bevacizumab Is a Predictive Factor for Outcomes of Macular Edema Associated with Central Retinal Vein Occlusion

PURPOSE To investigate whether retinal blood flow levels after intravitreal bevacizumab (IVB) treatment are correlated with the outcomes of patients with macular edema secondary to central retinal vein occlusion. METHODS This retrospective observational case study enrolled 44 cases nonischemic central retinal vein occlusion. In each patient, visual acuity, central retinal thickness, and mean blur rate, which was measured by laser speckle flowgraphy and represents retinal blood flow velocity, were examined. RESULTS At the end of the follow-up period (19.8 ± 8.8 months), 4 of 44 eyes (9.1%) converted to the ischemic type (converted group), whereas 40 (90.9%) remained unchanged (nonischemic group). Mean central retinal thickness significantly decreased and mean visual acuity significantly improved at 1 month after the first IVB injection in each group. Mean mean blur rate in the nonischemic group significantly increased, whereas it was unchanged in the converted group. The difference between the two groups was already significant after the first IVB injection. Subsequently, visual acuity worsened in the converted group. Multiple linear regression analysis indicated that the strongest correlation was between the last visual acuity and the last mean blur rate. CONCLUSION Blood flow measurements are useful for evaluating IVB treatments. Blood flow after IVB can predict outcomes in patients with central retinal vein occlusion.