Vascular endothelial cells migrate and proliferate to form new blood vessels. Any NV of the cornea's visual axis can threaten visual function directly or through secondary hemorrhage, scarring, or lipid deposition. Incidence of subsequent corneal graft rejection is estimated by one study to be 1.7 times higher in a setting of vascularized rather than nonvascularized host corneas. No ethnic predilection exists. No gender predilection exists.
Patients are almost always asymptomatic unless the central visual axis is involved.
Often, a history of poor compliance with proper CL wear and care is present. The CLs may be tight. It can be seen in direct illumination or in retroillumination as a continuum of the limbal peripheral vessel arcades. Measuring both the extent and the depth of the corneal NV is important. Deeper stromal vessels emerge through the cornea as straight vessels that arborize, occasionally accompanied by nerve fibers.