Short-term and long-term results after intravitreal bevacizumab therapy for macular oedema in branch retinal vein occlusion

Objectives: The aim of this study was to determine the possible correlation between the short- and long-term effects of intravitreal bevacizumab on macular oedema after branch retinal vein occlusion (BRVO). Material and methods: This prospective clinical study included fifteen eyes of patients with macular oedema after BRVO. Corrected distance visual acuity (CDVA), recorded in LogMAR units, central foveal thickness (CFT) and maximum foveal thickness (MFT) were evaluated at one month after first application and at least every 2 months for one year. PRN treatment protocol was used for all patients. Statistical calculation was performed with SPSS for Windows and Microsoft Excel. Results: Mean CFT decreased significantly (p<0,0001) from baseline 471,2 ± 151,7 μm to 285,9 ± 79,82 μm at 12 months. CDVA improved significantly (p<0,0001) from baseline 0,58 ± 0,34 to 0,1 ± 0,25 at the end of follow up period. Change from baseline in the CDVA after one month was significantly positively correlated with the change in CDVA after 12 months (r=0,76, p=0,001). Change in CFT after one month had a strong positive correlation (r=0,78, p=0,001) with change after 12 months. There was no statistically significant correlation between the number of injections and the changes in CDVA, CFT, MFT after a single injection. Conclusions: Single injection effects of bevacizumab may indicate long-term results on macular oedema after BRVO, but further and larger studies are necessary. Abbreviations: BRVO = Branch retinal vein occlusion, RVO = Retinal vein occlusion, CFT = Central foveal thickness, MFT = Maximum foveal thickness, VEGF = Vascular endothelial growth factor, MO = Macular oedema, CDVA = Corrected distance visual acuity, PRN = Pro-re-Nata, SD-OCT = Special-domain optical coherence tomography, FT = Foveal thickness, LogMAR = Logarithm of the Minimum Angle of Resolution, WHO = World Health Organization, RPE = Retinal pigment epithelium