Patients presenting with a recent CRVO (<2weeks) will be offered inclusion to undergo a vitrectomy with subsequent prolonged retinal vein cannulation and infusion of Ocirplasmin. The surgery is done by placing a microneedle in one of the branch retinal veins at the border of the optic disc. To increase the safety of this procedure a surgical stabilizer was developed. This procedure was abundantly tested and refined in multiple in vivo porcine experiments and the medication (Ocriplasmin) has already been tested for fibrinolytic activity used in 100-fold higher dosis intravenously and intra-arterially.