Extension Study to Gather Data on Effect of Macugen on the Corneal Endothelium

Inclusion Criteria: 1. Subjects of either gender aged \> or = to 50 years diagnosed with subfoveal neovascular Age-Related Macular Degeneration, Diabetic Macular Edema, or Retinal Vein Occlusion. 2. Best corrected visual acuity in the study eye between 85 and 20 ETDRS letters or between 20/20 and 20/400 using a Snellen chart. 3. Women must be using two forms of effective contraception, be post-menopausal for at least 12 months prior to study entry, or surgically sterile; if of child-bearing potential, a urine pregnancy test must be performed within 7 days prior to the first injection with a negative result. If the test is positive, a serum test must be done to confirm. The two forms of effective contraception must be implemented during the study and for at least 60 days following the last dose of test medication. 4. Provide written informed consent. 5. Ability to return for all study visits. Exclusion Criteria: Subjects will not be eligible for the study if subjects cannot attend all study-required visits, or if any of the following criteria are present 1. Unilateral ocular blunt trauma within one year of enrollment and no greater than 5% difference in central endothelial cell density between the 2 eyes. 2. intraocular surgery (cataract surgery and surgery for glaucoma without tube shunt or mini-shunt) within one year of enrollment. 3. Anterior segment laser surgery (laser trabeculoplasty) performed within one year of enrollment. 4. Glaucoma tube-shunt surgery 5. Previous history of corneal transplant in the study or non-study eye 6. Presence of vitreous macular traction 7. Previous therapeutic radiation in the region of the study eye 8. Any treatment with an investigational agent in the past 30 days for any condition 9. Known serious allergies to the components of pegaptanib sodium formulation Any of the following underlying diseases including:1. History or evidence of severe cardiac disease(e.g. NYHA Functional Class III or IV - see Appendix 2), clinical or medical history of unstable angina, acute coronary syndrome, myocardial infarction or revascularization within 6 months, ventricular tachyarrhythmias requiring ongoing treatment 7. History or evidence of clinically significant peripheral vascular disease, such as intermittent claudication or prior amputation 8. History or evidence of clinically significant impaired renal or hepatic function 8. Stroke (within 12 months of study entry) 9. Any major surgical procedure within one month of study entry 10. Significant media opacities, including cataract, which might interfere with visual acuity, assessment of toxicity. Subjects should not be entered if there is likelihood that they will require cataract or glaucoma surgery in either eye during the study treatment and follow-up period.