title: Study of the efficacy of intravenous tissue plasminogen activator in central retinal artery occlusion.
abstract: BACKGROUND
  Central retinal artery occlusion is a stroke of the eye caused by a blockage of its main blood supply by platelet-fibrin clot. Systemic thrombolysis has been successful in restoring perfusion to ischaemic tissue by fibrin-platelet clot lysis in ischaemic stroke and myocardial infarction. Several open-label studies have demonstrated efficacy of thrombolysis in the treatment of central retinal artery occlusion, with up to 60-70% of treated subjects experiencing an improvement in visual acuity. Most of these are given intraarterially, which is an invasive procedure and not widely applicable to all treatment centres. An alternative is the intravenous infusion of tissue plasminogen activator using existing stroke thrombolysis protocols. A systematic review of all observational studies of intravenous tissue plasminogen activator in acute central retinal artery occlusion showed that 48·5% of subjects had a four line or more visual acuity improvement with an acceptable rate of haemorrhagic complications, creating the equipoise necessary to conduct a randomised controlled trial.
  
  
  OBJECTIVE
  To determine the efficacy of intravenous thrombolysis in acute treatment of central retinal artery occlusion.
  
  
  METHODS
  A phase II, placebo-controlled, double-blind, randomised controlled trial comparing intravenous tissue plasminogen activator at 0·9 mg/kg to placebo (normal saline) 100 ml in a 1:1 block randomisation.
  
  
  RESULTS
  The primary outcome measure is an improvement of three lines or more on the Snellen visual acuity chart, which signifies a doubling of the visual angle.
authors.affiliation: Department of Ophthalmology, Flinders Medical Centre and Flinders University, Bedford Park, SA, Australia. celia.chen@health.sa.gov.au
authors.forename: Celia S
authors.initials: CS
authors.lastname: Chen
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Lee
authors.forename: Bruce
authors.initials: B
authors.lastname: Campbell
authors.forename: Mark
authors.initials: M
authors.lastname: Paine
authors.forename: Tien
authors.initials: T
authors.lastname: Lee
authors.forename: Clare
authors.initials: C
authors.lastname: Fraser
authors.forename: John
authors.initials: J
authors.lastname: Grigg
authors.forename: Romesh
authors.initials: R
authors.lastname: Markus
authors.forename: Keryn
authors.initials: K
authors.lastname: Williams
authors.forename: Doug J
authors.initials: DJ
authors.lastname: Coster
mesh_terms: D000328:Adult; D016494:Computer Security; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D010960:Plasminogen Activators / Q000008:administration & dosage* / Q000627:therapeutic use*; D020127:Recovery of Function; D015356:Retinal Artery Occlusion / Q000188:drug therapy*; D018401:Sample Size; D013923:Thromboembolism / Q000150:complications; D010959:Tissue Plasminogen Activator / Q000008:administration & dosage* / Q000627:therapeutic use*; D016896:Treatment Outcome; D014786:Vision Disorders / Q000209:etiology*; D014785:Vision, Ocular; D014792:Visual Acuity; D014794:Visual Fields
chemical_list: D010960:Plasminogen Activators; D010959:Tissue Plasminogen Activator