Cytokines associated with the prognosis of proliferative diabetic retinopathy after intravitreal conbercept injection combined with vitrectomy

Abstract Purpose : To investigate aqueous cytokine levels associated with proliferative diabetic retinopathy (PDR) prognosis after intravitreal conbercept injection (IVC). Methods: The Bio-Plex® 200 System and the Bio-PlexTM Human Cytokine Standard 27-Plex, Group I (Bio-Rad, Hercules, California, USA) measured aqueous humour cytokine and chemokine levels. In this retrospective study, control samples were collected from 10 patients undergoing pars plana vitrectomy (PPV), and test samples were collected from 15 patients undergoing PPV and IVC. Intraoperative complications and postoperative outcome parameters were compared. Cytokine concentration association with PDR prognosis after IVC combined with PPV was assessed by correlation analysis. Results: Baseline cytokine levels did not significantly differ between the control and IVC groups. IVC affected IL-8, VEGF and FGF levels, significantly increasing interleukin 8 (IL-8) levels and (P=0.05) decreasing VEGF and FGF levels (P<0.05). Intraoperative bleeding risk was lower in the IVC group versus the control group (P=0.022). Endodiathermy use was reduced in the IVC group versus the control group (P=0.006). The vitrectomy time in the IVC group was significantly shorter than in the control group (P=0.035). IL-8, VEGF, and FGF levels significantly positively correlated with vitrectomy time and intraoperative bleeding risk, intraoperative bleeding risk and endodiathermy use, and endodiathermy use, respectively. Conclusions: Conbercept may shorten the vitrectomy time, reduce intraoperative bleeding and affect IL-8, VEGF and FGF levels in PDR patient aqueous humour.