Angiography of the cornea using optical coherence tomography

Corneal neovascularization (NV) is the pathologic infiltration of blood vessels into an otherwise clear matrix of the cornea, resulting from a disruption in the balance between pro- and anti-angiogenic factors. It develops from a variety of causes including infections, immunologic processes, surgery, and trauma. These vessels may then lead to corneal edema, exudation of lipid, and corneal scarring, thus decreasing vision. They also compromise the immune privilege status of the cornea, and in cases of NV in corneal grafts they increase the risk of graft rejection. Proposed treatment options for pathological vessels of the cornea, in addition to addressing the underlying cause, include topical steroids1 ; photodynamic therapy2,3 ; argon laser therapy4,5 ; fine-needle diathermy6,7 ; topical, subconjunctival, and intrastromal anti-vascular endothelial growth factor agents8-12 ; and inhibition of insulin receptor substrate-1 expression.13 These treatments are also often used in combination, in order to have maximal effect against both active and established corneal NV.