Dexamethasone Intravitreal Implant Compared with Anti-vascular Endothelial Growth Factor Injection for Macular Edema Secondary to Retinal Vein Occlusion: a Meta-analysis

  Objective  To compare the efficacy and safety of intravitreal injections of dexamethasone implants (DEX) with anti-vascular endothelial growth factor (VEGF) in the treatment of macular edema (ME)secondary to retinal vein occlusion (RVO).

  Methods  The databases of Cochrane Library, PubMed, EMBASE, Ovid Medline, and ClinicalTrial.gov between January 1948 and June 2015 were searched for studies comparing DEX with anti-VEGF for the treatment of ME caused by RVO with key words "retinal vein occlusion", "macular edema", "anti-VEGF", "pegaptanib", "Macugen", "bevacizumab", "Avastin", "ranibizumab", "Lucentis", "aflibercept", "Trap-eye", "Ozurdex", "dexamethasone invitreal implant", and "clinical trial". We evaluated the quality of selected studies using Cochrane or Newcastle-Ottawa scale. Data were extracted and analyzed by RevMan 5.3 for Meta-analysis.

  Results  The mean difference in the mean changes of best corrected visual acuity (BCVA) in Early Treatment Diabetic Retinopathy Study (ETDRS) letters comparing DEX with anti-VEGF was 0.0495% confidence interval (CI):-2.07~2.15; P=0.97 at 1 month, -6.98(95% CI:-10.39~-3.58; P < 0.0001) at 3 months, -12.18(95% CI:-20.34~-4.03; P=0.003) at 4 months, and -11.84(95% CI:-19.66~-4.02; P=0.003) at 6 months. A greater reduction of central retinal thickness at 6 months was observed in the anti-VEGF group than in the DEX group (mean difference 135.86 μm; 95% CI:57.07~214.64 μm; P=0.0007). The incidence of intraocular pressure increase in the DEX group was significantly higher than that in the anti-VEGF group (OR=3.54, 95% CI:1.64~7.66, P=0.001).

  Conclusions  Anti-VEGF showed better effect than DEX in improving BCVA, reducing ME, and less influence on intraocular pressure for ME secondary to RVO. Therefore, anti-VEGF may have higher efficacy and safety than DEX for this condition.