While retina specialists can consider using intravitreal dexamethasone implants as corticosteroid therapy in retinal vein occlusion (RVO) for up to six months, a recent meta-analysis has shown that anti-vascular endothelial growth factor (VEGF) provides better best-corrected visual acuity (BCVA) results and decreased central subfield thickness (CST). Though significant functional and anatomical improvement was found in both dexamethasone implants and anti-VEGF treatment, the implants showed adverse effects such as significantly higher intraocular pressure (IOP) and elevated rates of cataract formation than the anti-VEGF treatment.

The meta-analysis compiled data from four randomized controlled trials that assessed 969 eyes in total. The treatments in all four studies were the same: 0.5mg ranibizumab or 0.7mg Ozurdex (Allergan). After the dexamethasone implant injection, all of the studies showed improvement in BCVA in the first two months that gradually decreased over time. The branch and central subtypes each presented with similar effects, which illustrates the identical pathological processes of the two RVO subtypes and the identical effects of these treatments.

Researchers concluded that anti-VEGF treatment should remain the first choice when treating RVO patients. To draw more precise conclusions, they believe future studies should compare functional improvements, adverse effects and economic costs between dexamethasone implants and anti-VEGF treatment, with the two modalities studied under the as-needed treatment model and the RVO subtype taken into consideration. They also consider contributions toward new treatment methods such as combined therapy and investigations to optimize clinical efficacy, economic cost and side effects are worthwhile.

Gao L, Zhou L, Tian C, et al. Intravitreal dexamethasone implants versus intravitreal anti-VEGF treatment in treating patients with retinal vein occlusion: a meta-analysis. BMC Ophthalmol. January 8, 2019. [Epub ahead of print].