Evaluating the effect of vitreomacular interface abnormalities on anti-vascular endothelial growth factor treatment outcomes in diabetic macular edema by optical coherence tomography: A systematic review and meta-analysis

To evaluate the effect of vitreomacular interface (VMI) configuration on treatment outcomes after intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy for diabetic macular edema (DME) using optical coherence tomography (OCT). A systematic literature search was performed on PubMed, Embase, web of science and clinicaltrials.gov. The primary outcome parameters were central macular thickness (CMT), best-corrected visual acuity (BCVA) and mean injection numbers. We performed this meta-analysis by Review Manager (RevMan) 5.4.1. The impact of epiretinal membrane (ERM), vitreomacular traction (VMT) and vitreomacular adhesion (VMA) on the treatment outcomes were analyzed separately. 9 clinical studies involving 699 eyes were eligible for the meta-analysis for evaluating the effect of ERM/VMT on efficacy. And 7 studies with 610 eyes were included to access whether VMA affected the response to anti-VEGF therapy in patients with DME. The ERM/VMT group had poorer CMT reductions than the control group at 1 month ([MD] 52.91 mm, P<0.00001), while no significant difference at 3 months ([MD] 43.95 mm, P = 0.22) and over 12 months ([MD] 30.51 mm, P = 0.45). No statistically significant difference in the mean BCVA change at 1 month ([MD] -0.03 Log MAR, P = 0.79), whereas ERM/VMT group had poor visual acuity gains at 3 months ([MD] 0.08 Log MAR, P = 0.003), and a tendency of poor vision improvement over 12 months follow-up ([MD] 0.07 Log MAR, P = 0.11). There was no significant difference in the visual and anatomical results over 3 months in DME patients with or without VMA ([MD] -21.92 mm, P = 0.09; [MD] 1.79 letters, P = 0.22). Besides, VMI configuration was not found to affect mean injection numbers. The limited evidence suggested that ERM/VMT was associated with worse CMT reduction at 1 month, poor BCVA gain at 3 months and a tendency of limited vision improvement over 12 months follow-up in DME patients treated with anti-VEGF agents. And VMA may not adversely affect the anatomic and functional outcomes. However, the results of this meta-analysis should be interpreted with caution because of the heterogeneity among study designs.