What is the impact of intravitreal injection of conbercept on neovascular glaucoma patients: a prospective, interventional case series study

Abstract

Background The aim of the present study was to evaluate the efficacy and safety of intravitreal conbercept combined with trabeculectomy and panretinal photocoagulation for neovascular glaucoma (NVG). Methods Fifty patients (54 eyes) with NVG were included in this prospective study. Fifty-two eyes initially underwent intravitreal conbercept (0.5mg/0.05ml), and then trabeculectomy and panretinal photocoagulation were performed. Preoperative and postoperative best-corrected visual acuity (BCVA), intraocular pressure (IOP), number of antiglaucoma medications, and surgical complications were recorded. The levels of VEGF-A, TGF-β1 and PLGF in aqueous humour that were collected during surgery were measured by enzyme-linked immunoabsorbent assay (ELISA). Light microscopy and transmission electron microscopy were used to observe the surgically excised trabecular tissue; enucleation was performed for 2 eyes, and light microscopy was used as the histopathological control. Results The follow-up period after trabeculectomy was 1 year. Of the 52 eyes, 39 eyes completed the 1-year follow-up and 13 eyes were lost to follow up. Recurrence of iris neovascularization was observed in 5 eyes, 9 eyes had hyphema, 16 eyes had filter bled scarring, no eye had complication attributable to the drug. The mean IOP was reduced from 48.1±14.2 mmHg to 23.2±8.7 mmHg, and the mean number of antiglaucoma medications used decreased from 3.0 (3.0, 4.0) to 1.0 (0.0, 1.0) at 1 year (both P < 0.05). The complete success rate was 76.9%, 76.9%, 71.0%, 51.6%, 32.3% at 1week, 1 month, 3 months, 6 months and 12months when the cut off of IOP was 18mmHg. After patients underwent intravitreal injection, the concentrations of VEGF-A and TGF-β1 in aqueous humour in NVG patients decreased from 168.8±13.4 pg/ml and 159.6±15.4 pg/ml to 160.2±7.6 pg/ml and 151.9±2.3 pg/ml, respectively (both P < 0.05). Light microscopy revealed neovascularization regression in the iris in specimens with intravitreal conbercept. Electron microscopy revealed trabecular endothelial cells degeneration in the conbercept-treated specimens. Conclusions Our initial findings suggest that intravitreal conbercept is an effective treatment for managing neovascular glaucoma, with fewer postoperative complications in the short-term. Trial registration Current Controlled Trials ChiCTR1800019918, 8 December 2018, Retrospectively registered.