1. Study hypothesis: Injection of t-PA, a thrombolytic drug (clot busting medicine)into the ophthalmic artery (the blood vessel feeding the eye), in patients with recent severe central retinal vein occlusion, may reopen the central retinal vein and improve retinal blood flow, which may in turn improve visual acuity and prevent the long-term complications of the disease.
2. Experimental intervention: An outpatient procedure during which the ophthalmic artery is selective catheterized (with a small plastic tube called a microcatheter introduced from the artery of the leg) and infused with t-PA during two hours.
