Neovascularization of the cornea, also called corneal pannus, is the growth of blood vessels from the limbus into the cornea. The blood vessels can be very superficial or deep in the corneal stroma. Corneal pannus is often divided into 2 classes: micropannus, which denotes vascular ingrowth of 2 mm or less and macropannus, which is ingrowth of greater than 2 mm. Neovascularization of the cornea is a nonspecific sign of ocular inflammation. Often, the inflammation is sub-clinical and patients will not be aware of the vascularization, nor will they have any visual complaints. Contact lens wear and eyelid inflammation (blepharitis) are classically associated with asymptomatic pannus formation. More obvious causes of inflammation and corneal neovascularization include corneal ulcers, traumatic corneal scars, and atopic keratoconjunctivitis. Though the blood vessels are nonspecific, they do indicate a chronicity of inflammation as blood vessels do not migrate into the cornea acutely.