Neovascular Glaucoma

Abstract

Neovascular glaucoma (NVG) is a secondary ocular pathological condition resulting from a myriad of ocular and systemic conditions with retinal ischemia as a mediator in over 95% of cases. NVG is caused by the growth of a fibrovascular membrane secondary to a local angiogenic stimulus over the trabecular meshwork obstructing aqueous outflow. This results in an initial secondary open-angle glaucoma stage that may be amenable to intraocular pressure (IOP)-lowering medications and modulation of the underlying ischemic process, often in combination with panretinal photocoagulation and adjunctive use of vascular endothelial growth factor inhibitors. In the more advanced stages of neovascularization, connective tissue myofibroblasts associated with new vessel growth contract causing progressive synechial closure of the anterior-chamber angle. Elevation of IOP, once significant secondary angle closure is established, tends to be refractory to topical and oral IOP-lowering medications and often requires glaucoma surgical interventions.

Fig. 1

a–c : Right (a ) and left eye (b ) of a patient with severe PDR and bilateral NVG refractory to topical and oral IOP-lowering therapy requiring bilateral glaucoma drainage device implantation. Two tube shunts are present in the left eye with persistent NVI with inferior dyscoria and ectropion uvea after dense PRP and repeated VEGF inhibitor injection. c High magnification of the left eye shows NVI and the tip of tube shunt.