Abstract:AIM: To compare the efficacy and safety of intravitreal aflibercept with dexamethasone implant in the treatment of macular edema (ME) associated with diabetic retinopathy (DR) or retinal vein occlusion (RVO). METHODS: A comprehensive search of studies comparing dexamethasone and aflibercept in patients with ME was conducted at PubMed, Embase, and Cochrane Central Register of Controlled Trials from the beginning of library to April 16, 2021. Extracting the data including best-corrected visual acuity (BCVA), central retinal thickness (CRT), number of injections and serious adverse events (SAEs) from the final qualified articles. RevMan 5.3 software was used for Meta-analysis of the included studies. RESULTS: Totally 7 studies with 369 eyes were included. The causes of ME in the final screening study included RVO and DR. Compared with the aflibercept treatment group, the BCVA of the dexamethasone implant treatment group showed no significant difference in the follow-up for 3mo [mean difference (MD): -0.05, 95% confidence interval (CI): -0.11, 0.02; P=0.17] and 12mo (MD: -0.01, 95%CI: -0.38, 0.37; P=0.98), but it was slightly worse than the aflibercept group at 6mo (MD: 0.12, 95%CI: 0.03, 0.21; P=0.008). In terms of CRT reduction, there was no significant difference between the two groups at 3mo (MD: -28.14, 95%CI: -79.95, 23.67; P=0.29), 6mo (MD: 27.67, 95%CI: -84.89, 140.24; P=0.63), and 12mo (MD: -59.00, 95%CI: -127.37,9.37; P=0.09). However, dexamethasone implant had fewer injections, but more adverse events such as elevated intraocular pressure (IOP) and cataract. CONCLUSION: Intravitreal injection of aflibercept and dexamethasone implant can both effectively increase BCVA and reduce CRT. Compared with aflibercept, dexamethasone implant is not inferior in improving vision and reducing CRT in the initial treatment period (3mo) and long-term treatment period (12mo). Besides, it has fewer injections and more likely to cause elevated IOP and cataract.