Intravitreal bevacizumab injections versus dexamethasone implant for treatment-naïve retinal vein occlusion related macular edema.

Purpose: To compare the short-term effects of three monthly intravitreal bevacizumab (IVB) injections to single dexamethasone (DEX) implantation in treatment-naïve patients with cystoid macular edema (CME) secondary to branch (BRVO) and central retinal vein occlusion (CRVO).

Design: A retrospective single-center study.

Subjects: A total of 135 eyes of 135 patients with BRVO (n=83) and CRVO (n=52).

Methods: Changes in clinical parameters were recorded before treatment and at the first and third month after commencement of IVB (n=121) and DEX (n=14).

Main outcome measures: Central retinal thickness (CRT), intraocular pressure (IOP), and best-corrected visual acuity (BCVA).

Results: The baseline parameters were comparable between IVB and DEX groups. After the first month, CRT decreased by 131.3±42.9 μm in IVB and by 266.9±48.3 μm in DEX (mean ± SEM; p =0.047). IOP change was -0.29±0.39 mmHg in IVB and +3.70±2.34 mmHg in DEX ( p =0.005). IOP elevation to ≥25 mmHg and ≥5 mmHg from the baseline was observed in two of the DEX- and in none of the IVB-treated eyes ( p =0.010). After the third month, no differences regarding CRT and IOP were observed between the treatment modalities. Moreover, BCVA gain was comparable between IVB (0.37±0.05 logarithm of minimum angle of resolution [logMAR] units) and DEX (0.33±0.30 logMAR units) groups.

Conclusion: DEX was associated with faster resolution of CME, but had greater probability for short-term IOP elevation when compared to IVB. After the third month, treatments were comparably effective. Anatomical outcomes and adverse drug reactions of IVB versus DEX should be considered case specifically in patients having CME secondary to BRVO/CRVO.