Intravitreal injection of tissue plasminogen activator for central retinal vein occlusion.

Abstract

This pilot study evaluated the feasibility of intravitreal injections of tissue plasminogen activator (tPA) in eyes with central retinal vein occlusion (CRVO). Between August 1997 and October 2000, 9 eyes with CRVO were treated with intravitreal injection of tPA, 100 micrograms (50 micrograms/0.1 mL), and paracentesis. After the injection, each patient was placed at strict bed rest in the supine position for 6 hours. Each patient was administered one baby aspirin daily. Best corrected visual acuity with Light House charts was obtained at each visit. A change of 3 or more lines of vision from pretreatment levels at 6 months' follow-up or a change in one level (i.e., counting fingers to hand motions) was deemed significant. All patients were followed up for at least 6 months. Four of 9 eyes (44%) showed 3 or more lines improvement at 6 months. In this group, the average improvement was 7 lines. Two eyes showed 6 or more lines loss of vision at 6 months. Four eyes showed dramatic improvement in visual acuity within 1 month of injection. There were no adverse effects related to treatment. Three eyes subsequently developed retinal or anterior-segment neovascularization requiring panretinal photocoagulation; all were graded as ischemic CRVO on fluorescein angiography at baseline. Intravitreal tPA can be injected safely and easily. Local injection of tPA should spare the patient the serious systemic risks of intravenous tPA administration, such as stroke. Given the morbidity of CRVO, further investigation with this therapy to establish both efficacy and safety seems warranted.