A Randomized Study Comparing Ranibizumab to Sham in Patients With Macular Edema Secondary to CRVO

Inclusion Criteria: 1. Male and female ≥ 50 years 2. Patients who have findings consistent with CRVO 3. Patients who have a history of decreased visual acuity ≤ 6 months 4. Patients who have a best corrected visual acuity (BCVA) letter score in the study eye of ≤ 73 (4 m distance) or ≥ 6 (1 m distance) using an ETDRS chart 5. Patients who have a macular edema verified by OCT 6. Patients who have macular edema in the study eye with the following characteristics as determined by fluorescein angiography: * secondary to non-iscemic CRVO defined as non-perfusion \< 10 DA OR * secondary to ischemic CRVO defined as non-perfusion \> 10 DA 7. Willing and able to give written informed consent and who are willing and able to comply with study procedures 8. Ability to cooperate with photo and OCT examinations Exclusion Criteria: 1. Neovascularisations in the study eye at baseline 2. Previous treatment with or participation in a clinical trial (for either eye) involving anti-angiogenics drugs 3. Use of other investigational drugs 4. Prior treatment in the study eye with verteporfin, external-beam radiation therapy, subfoveal laser photocoagulation, vitrectomy, or transpupillary thermotherapy. 5. History of submacular surgery in the study eye, glaucoma filtration, corneal transplantation surgery 6. Previous or current intravitreal or sub-Tenon drug delivery in the study eye 7. Laserphotocoagulation (juxtafoveal or extrafoveal) in the study eye within one month preceding Baseline 8. Extracapsular extraction of cataract with phacoemulcification within three months preceding Baseline, or a history of post-complications within the last 12 months preceding Baseline in the study eye (uveitis, cyclitis etc) 9. History of uncontrolled glaucoma in the study eye (defined as intraocular pressure ≥ 25 mmHg despite treatment with anti-glaucoma medication) 10. Previous violation of the posterior capsule in the study eye unless it occurred as a result of YAG laser posterior capsulotomy in assosiation with prior, posterior chamber lens implantation 11. Afakia with absence of the posterior capsule in the study eye 12. Active intraocular inflammation in the study eye 13. Any active infection involving the ocular adnexa including infectious conjunctivitis, keratitis, scleritis, endophthalmitis, as well as ideopathic or autoimmune-associated uveitis in either eye 14. Vitreous hemorrhage or history og rhegmatogenous retinal detachment or macular hole in the study eye 15. Any current intraocular condition in the study eye (cataract or diabetic retinopathia) that in the opinion of the investigator, could either require medical or surgical intervention during the study period for the next 6 months 16. Ocular condition that requires chronic concomitant therapy with systemic or topical ocular corticosteroids. 17. Current treatment for active systemic infection. 18. Current use or likely need for systemic medications known to be toxic to the lens, retina or optic nerve. 19. History of other diseases, metabolic dysfunction, physical examination finding, or clinical laboratory finding giving reasonable suspicion of a disease or condition that contraindicates the use of an investigational drug or might affect interpretation of the results of the study or render the subject at high risk for treatment complications 20. History of hypersensitivity or allergy to fluorescein 21. Inability to obtain fundus photographs or fluorescein angiograms of sufficient quality to be analyzed 22. Pregnant or nursing (lactating) women 23. Pre-menopausal women of child-bearing potential not using adequate contraception. 24. History of malignancy of any organ system, treated or untreated, within the past 5 years whether or not there is evidence of local recurrance or metastases.