Archives: Researchers found that an injection of autologous plasmin into the vitreous was very effective in reducing macular edema and improving vision (from 20/80 to 20/30) in branch retinal vein occlusion patients.  These are great results, and remarkably, the results lasted up even up to six months after one injection. I don’t know how much it costs, but maybe this will be more cost effective than Avastin or laser.