AQUEOUS HUMOR CYTOKINE LEVELS AND REBOUND MACULAR EDEMA AFTER CONBERCEPT TREATMENT IN PATIENTS WITH CENTRAL RETINAL VEIN OCCLUSION.

PURPOSE: This study aimed to investigate the effect of intravitreal conbercept (IVC) injections on the aqueous humor concentrations of angiogenic and inflammatory cytokines in patients with macular edema (ME) due to central retinal vein occlusion and to determine whether changes in cytokine levels after IVC are associated with the development of rebound ME. METHODS: Forty-nine patients with ME caused by central retinal vein occlusion were included in this retrospective study. Monthly doses of IVC were administered for three months, followed by a Pro Re Nata dosing regimen. Rebound ME was defined as ≥110% increase in the foveal thickness compared with the baseline. Whenever injections were administered, aqueous humor samples were obtained. Multiplex bead assay was used to measure seven angiogenic and inflammatory cytokines in aqueous humor samples. RESULTS: At baseline, patients with central retinal vein occlusion showed significantly higher aqueous humor concentrations of vascular endothelial growth factor, placental growth factor, monocyte chemoattractant protein-1, platelet-derived growth factor-AA, IL-6, IL-8, and IL-12. At 1-month and 2-month follow-up after IVC, significantly decreased concentrations of all cytokines were observed. During the 12-month follow-up period, 6 of the 49 eyes (12.2%) showed rebound ME after IVC. Patients with rebound ME showed significantly elevated levels of inflammatory but not angiogenic cytokines. CONCLUSION: Angiogenic and inflammatory cytokines were overexpressed in patients with ME caused by central retinal vein occlusion. Conbercept treatment influenced the concentrations of various inflammatory cytokines and reduced aqueous vascular endothelial growth factor and placental growth factor concentrations. Rebound ME may occur due to disruption of the balance between angiogenic and inflammatory cytokines and an accompanying excess of inflammatory cytokines but not angiogenic cytokines, after antivascular endothelial growth factor therapy.

Comparison of the Effect of Intravitreal Conbercept and Ranibizumab on Aqueous Humor Cytokines in Central Retinal Vein Occlusion-Related Macular Edema.

Purpose: To analyze changes in the levels of angiogenic and inflammatory cytokines following the administration of intravitreal conbercept (IVC) or intravitreal ranibizumab (IVR) in patients with macular edema (ME) due to central retinal vein occlusion (CRVO). Methods: This retrospective study was conducted between June 2015 and January 2016 in The First Hospital of China Medical University. We administered 3 consecutive monthly doses of IVC (23 eyes) or IVR (19 eyes) in 42 eyes with CRVO-ME. At each injection, we collected aqueous humor samples and used multiplex bead assays to measure 7 angiogenic and inflammatory cytokines [vascular endothelial growth factor (VEGF), placental growth factor (PlGF), platelet-derived growth factor (PDGF)-AA, monocyte chemoattractant protein (MCP)-1, and interleukins (ILs)-6, 8, and 12]. Results: Visual acuity and ME improved significantly in both groups during the treatment period. Compared with the baseline, all the cytokine concentrations in the aqueous humor samples decreased significantly at 1 and 2 months after the initial dose of IVC or IVR. The improvement of visual acuity and ME and the changes of aqueous humor cytokine levels were similar in both groups. Concentrations of VEGF, PlGF, MCP-1, PDGF-AA, IL-6, IL-8, and IL-12 levels did not show significant intergroup differences after 1 month (P = 0.369, 0.312, 0.185, 0.353, 0.135, 0.487, and 0.337, respectively) and 2 months (P = 0.305, 0.376, 0.230, 0.519, 0.114, 0.960, and 0.830, respectively) of follow-up. Conclusion: IVC and IVR induced comparable improvements in clinical parameters, along with equivalent reductions in the concentrations of angiogenic and inflammatory cytokines in the aqueous humor.