Comparison of immediate versus deferred intravitreal Bevacizumab in macular oedema due to branch retinal vein occlusion: a pilot study

To compare visual and anatomical recovery of immediate versus deferred intravitreal Bevacizumab for the treatment of macular oedema secondary to branch retinal vein occlusion (BRVO). In a pilot study, 40 treatment na < ve patients of branch retinal vein occlusion with macular oedema and vision 6/12 or less presenting within one month of onset were randomised into 2 groups (20 each) to receive either immediate intravitreal Bevacizumab or deferred (after 3 months of observation). Outcome in terms of visual recovery and decrease in central macular thickness on the Optical Coherence Tomography (OCT) from pre-treatment level was analysed at 6 and 12 months from starting of treatment and compared between the two groups. The mean visual gain in the two groups early and delayed intervention was 0.38 log MARs and 0.15 log MAR units, respectively, and the superior vision gain in the early intervention group was statistically significant (p < 0.001). The difference in visual improvement between the two groups persisted till 1 year of follow-up. The early intervention group required fewer injections (2.6 +/- 71 vs. 3.5 +/- 0.51), and rescue laser treatment (15 vs. 25%) as compared to deferred group. Both groups showed significant decrease in central macular thickness (328 and 289 A mu, respectively) from baseline thickness, but the difference between the two groups was not statistically significant (p = 0.45). Both early as well as deferred injection of Bevacizumab in macular oedema due to BRVO resulted in reduction of macular oedema and visual gain but immediate injection were associated with significantly greater visual gain with lesser number of injections fewer rescue laser treatment.