Interventions for Central Retinal Vein Occlusion: An Evidence-Based Systematic Review
Presented at: Association for Research in Vision and Ophthalmology meeting, April/May 2006, Fort Lauderdale, Florida.
Received 15 May 2006; accepted 6 November 2006.
Topic
To assess the evidence for the effectiveness of interventions to improve visual acuity (VA) and prevent or treat neovascularization secondary to central retinal vein occlusion (CRVO).
Clinical Relevance
Central retinal vein occlusion is a common cause of visual morbidity and blindness. Many different interventions have been advocated, but the evidence justifying their use remains unclear.
Methods/Literature Reviewed
English and non-English language articles were retrieved using a keyword search of Medline (1966 onwards), Embase, the Cochrane Collaboration, the National Institutes of Health Clinical Trials database, and the Association for Research in Vision and Ophthalmology (2003–2005). This was supplemented by manually searching references of review articles. Two investigators independently identified all randomized clinical trials (RCTs) on interventions in CRVO with more than 3 months’ follow-up.
Results
Of 4133 citations retrieved, 17 RCTs comparing intervention with a control group were identified. There were 4 RCTs on laser photocoagulation. Grid macular laser photocoagulation did not improve VA in CRVO with macular edema. Prophylactic panretinal photocoagulation did not prevent angle and iris neovascularization in ischemic CRVO, but resulted in regression of angle and iris neovascularization and reduced progression to neovascular glaucoma. There were 4 RCTs that reported improvement in VA with inpatient hemodilution, 2 RCTs with no significant improvement, and 1 RCT showing deterioration in VA after outpatient hemodilution. Randomized clinical trials evaluating ticlodipine, troxerutin, and streptokinase showed a limited or no benefit.
Conclusions
This review found limited level I evidence for any intervention to improve VA in patients with CRVO. Panretinal photocoagulation resulted in regression of neovascularization. Hemodilution may improve vision in some patients, but the data conflict. More robust randomized controlled trials evaluating current treatments for CRVO are needed. The results of ongoing RCTs on intravitreal triamcinolone, anti–vascular endothelial growth factor agents, and chorioretinal anastomosis are awaited with interest.
1Cheltenham General Hospital, Cheltenham, United Kingdom.
2Centre for Eye Research Australia, University of Melbourne, Melbourne, Australia.
3Department of Community, Occupational, and Family Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
4Singapore Eye Research Institute, National University of Singapore, Singapore.
5Royal Victorian Eye and Ear Hospital, Melbourne, Australia.
Correspondence to Tien Y. Wong, MD, PhD, Centre for Eye Research Australia, University of Melbourne, 32 Gisborne Street, East Melbourne 3002, Australia.
Manuscript no. 2006-533.
Funding provided by the Victorian government, Melbourne, Australia (Science Technology and Innovation Grant), and Sylvia and Charles Viertel Charitable Foundation, Melbourne, Australia (Sylvia and Charles Viertel Clinical Investigator Award [TYW]).