Treatment of recent onset central retinal vein occlusion with intravitreal tissue plasminogen activator: a pilot study

Abstract
AIMS To study the effects of intravitreal tissue plasminogen activator (tPA) in recent onset central retinal vein occlusion (CRVO). METHODS 15 patients with recent onset CRVO (from 1–21 days' duration, mean 8 days) were given 75–100 μg of tPA intravitreally associate with low dose low molecular weight heparin. CRVO was perfused in nine patients and with mild ischaemia not exceeding 100 disc diameters in six patients. Follow up ranged from 5 to 21 months for 14 patients (mean 8 months). Visual acuity measurement, macular threshold (Humphrey perimeter), fluorescein angiography with the scanning laser ophthalmoscope with special emphasis on retinal circulation times, and retinal perfusion were performed at days 0, 1, and 8 and months 1, 3, and 6. RESULTS Visual acuity was significantly improved on the first day after treatment in only one eye, and decreased transiently in six eyes (40%). Retinal blood velocity was not significantly modified by tPA injection. Retinal ischaemia developed in six eyes (43%), leading to panretinal photocoagulation in five eyes including one with rubeosis iridis. At the end of follow up, visual acuity had improved to 20/30 or better in five eyes (36%), including two with complete recovery; visual acuity was worse than 20/200 in three eyes (28%). No complication of tPA injection was observed. CONCLUSION Intravitreal tPA treatment for CRVO appears to be simple and safe, but did not significantly modify the course of the occlusion in our patients immediately after treatment. Final visual outcome did not differ significantly from that observed in the natural course of the disease, but final visual acuity seemed to be slightly better. A randomised study is required to determine if intravitreal tPA actually improves visual outcome in CRVO.