Efficacy of Intravenous Tissue-Type Plasminogen Activator in Central Retinal Artery Occlusion

Abstract

Background and Purpose-Central retinal artery occlusion is caused by a platelet-fibrin thrombus or embolic occlusion and is a stroke of the eye. Observational studies suggest that thrombolytics may restore ocular perfusion and visual function. We hypothesized that intravenous tissue-type plasminogen activator (tPA) administered within 24 hours of symptom onset might restore ocular perfusion and visual function. Methods-A placebo-controlled, randomized trial of intravenous tPA versus intravenous saline was performed in patients with clinically defined central retinal artery occlusion within 24 hours of symptom onset. tPA was administered at a total dose of 0.9 mg/kg, with 10% given as a 1-minute bolus and the remainder over 1 hour. An improvement of visual acuity of 3 lines or more was considered significant. Results-Twenty-five percent (2 of 8) of the tPA group experienced the primary outcome at 1 week after tPA versus none of the placebo group. One patient had an intracranial hemorrhage. The visual acuity improvement of these 2 patients was not sustained at 6 months. In both patients, tPA was administered within 6 hours of symptom onset. Conclusions-Although essentially a negative study, it does add to the evidence base of reperfusion in central retinal artery occlusion by showing that the time window for intervention is likely to be Ͻ6 hours. Reocclusion is a potential problem and may require adjuvant anticoagulation. Future studies should concentrate on determining the efficacy of thrombolytics in the Ͻ6-hour time window. Clinical Trial Registration-URL: http://www.anzctr.org.au. Unique identifier: 83102.

Systemic Prostaglandin E1 to Treat Acute Central Retinal Artery Occlusion

“…Most studies included a small number of subjects, were conducted using a retrospective study design, and reported limited effectiveness of the tested treatments. As we also found, some studies found correlations between shorter time to treatment and favorable visual outcomes, 6,[8][9][10]16 whereas others found no significant effects of time to treatment on visual outcomes. 13,14 Restoration of possible blood flow or vasodilation after treatments was examined in several studies.…”

Retrobulbar Spot Sign Predicts Thrombolytic Treatment Effects and Etiology in Central Retinal Artery Occlusion

“…4 A small randomized trial (n=16) on intravenous tissue-type plasminogen activator found improved visual acuity in 25% of patients, versus none after placebo. 3 For the first time, we correlated treatment effects with the occurrence of a spot sign. We found relevant treatment effects only in spot sign-negative CRAO.…”

“…Studies investigating intra-arterial or intravenous thrombolysis have yielded inconsistent results. [2][3][4] Ocular color-coded duplex sonography (OCCS) allows direct examination of the central retinal artery. Only few studies report on its value.…”

Evidence for an enduring ischaemic penumbra following central retinal artery occlusion, with implications for fibrinolytic therapy

“…This is the only gold standard trial to be undertaken to date but, in the event, safety concerns among patients undergoing LIF led to its abandonment at a stage when there was no significant difference in functional outcomes between the 2 study arms (Schumacher et al, 2010). Nevertheless, further trials are planned or recommended, not least to determine the role of fibrinolytic intervention within a narrower time-window from CRAO onset (Aldrich et al, 2008;Biousse, 2008;Atkins et al, 2009;Schumacher et al, 2010;Chen et al, 2011).…”