Adjuvant treatment of neovascular glaucoma with conbercept: clinical efficacy and histopathological analysis of trabeculectomy specimens

Background Neovascular glaucoma (NVG) often occurs secondary to ocular ischemic diseases.Intravitreal injection of bevacizumab or ranibizumab as an adjunct therapy or NVG is safe and efficient.However, the efficacy of intravitreal injection of conbercept for NVG is still under exploration. Objective This study was to evaluate the efficacy and safety of intravitreal conbercept combined with trabeculectomy and panretinal photocoagulation for NVG. Methods A prospective, interventional case series study was performed.Twenty-six patients (27 eyes) who were diagnosed with NVG in Tianjin Eye Hospital were included.Twenty-five eyes were initially injected with conbercept into vitreous, then trabeculectomy and panretinal photocoagulation were performed, the best corrected visual acuity (LogMAR), intraocular pressure and treatment-related indexes were examined before and after treatment, the intraoperative and postoperative complications were evaluated.Light microscopy and transmission electron microscopy were used to observe the surgically excised trabecular tissue.Enucleation was performed on 2 eyes, and the surgically excised tissue was taken as the histopathological controls. Results At six monthes after surgery, the intraocular pressure of the 25 patients with intravitreal injection of conbercept were decreased from (48.8±10.2) mmHg to (18.0±4.3) mmHg, the number of anti-glaucoma medications were decreased from 3.0 (3.0, 4.0) to 0.0 (0.0, 1.0) (both at P 0.05). Twenty-one eyes displayed controlled intraocular pressure (≤21 mmHg) after treatment.Regression of neovasculariztion in the surface of iris and thin-walled vessels in the iris stroma in specimens with intravitreal injection of conbercept were revealed by light microscopy.New vessels decreased, endothelial cell degeneration and vascular occlusion or cavity in the iris stroma in the conbercept-treatment specimens were revealed by transmission electron microscopy. Conclusions A comprehensive therapy for NVG can regress iris neovascularization, reduce postoperative complication, effectively control intraocular pressure and preserve visual function by intravitreal injection of conbercept, anti-glaucoma surgery and panretinal photocoagulation. Key words: Neovascular glaucoma; Conbercept; Anti-vascular endothelial growth factor; Trabeculectomy; Histopathology