Multicenter study of the European Assessment Group for Lysis in the Eye (EAGLE) for the treatment of central retinal artery occlusion: design issues and implications. EAGLE Study Report No. 1

Abstract

None of the “classic” conservative therapies used for the treatment of acute central retinal artery occlusion (CRAO) has proven effective in retrospective studies. Over the past 10 years, local intra-arterial thrombolysis (administered in situ, directly in the ophthalmic artery via catheter angiogram) has been used increasingly in various centers, particularly in Germany. Small case series and retrospective studies have suggested improvement of the visual function in about 25% of treated patients; however, the use of in situ thrombolysis for the treatment of acute CRAO is debated, and remains limited to pilot centers. In 2002, a German group initiated a randomized prospective multicenter study evaluating the therapeutic efficacy of in situ thrombolysis in acute CRAO [The European Assessment Group for Lysis in the Eye (EAGLE)]. Inclusion criteria were age between 18 and 75 years, CRAO not older than 20 hours, with a visual acuity less than 0.32. Exclusion criteria were branch retinal artery occlusion (BRAO), cilioretinal arteries supplying the macula, and severe systemic disorder. Each included patient was randomized to conservative or local intra-arterial thrombolysis therapy. The conservative regime included bulbus massage, lowering intraocular pressure with topical beta-blocker and acetazolamide, acetylsalicylic acid, heparin, and isovolemic hemodilution. Local intra-arterial thrombolysis was performed using a maximum of 50 mg rtPA injected directly into the ophthalmic artery by an experienced interventional neuroradiologist. During the following five days, all patients received heparin. Primary study end point was visual acuity one month after therapy (in comparison with visual acuity before therapy). The authors calculated that they would need 100 patients per group (a total of 200 patients). Participating centers were located in Germany, Switzerland, and Austria. Between June 2002 and April 2005, only 47 patients were included. The study is therefore being continued. The authors emphasize that, to this date, treatment of CRAO with in situ thrombolysis should only be performed as part of a research study and not routinely. They welcome new study centers to join them in order to increase the inclusion rate.—Valérie Biousse