To compare the clinical outcomes of intravitreal bevacizumab with and without posterior subtenon triamcinolone acetonide injections for macular edema with branch retinal vein occlusion.

Intravitreal bevacizumab injection (single group) or intravitreal bevacizumab injection with posterior subtenon triamcinolone acetonide injection (combined group) were performed in 30 eyes each, and intravitreal bevacizumab injection was given once a month in both groups until macular edema was in the normal range. A best corrected visual acuity and central macular thickness were measured pre- and post-injection.

The required number of injections to achieve improved macular edema in the normal range was 2.8 ± 0.5 times in the single group and 2.0 ± 0.6 times in the combined group. Six months after injection, average central macular thickness decreased to 185.3 ± 63.5 µm in the single group and to 260.0 ± 74.6 µm in the combined group. The best corrected visual acuity (log MAR) improved from 0.71 ± 0.63 to 0.35 ± 0.44 in the single group and from 0.67 ± 0.42 to 0.08 ± 0.11 in the combined group. The number of cases in which the central macular thickness increased again within 6 months after the injections was 19 eyes in the single group and 6 eyes in the combined group.

In macular edema with branch retinal vein occlusion, early rapid recovery of visual acuity and decrease of central macular thickness were observed due to the synergistic effect of bevacizumab and triamcinolone acetonide in combined therapy, and the recurrence frequency of macular edema was reduced by the long-term effect instilled by the long half-life of triamcinolone acetonide.