Some birthmarks are from extra color (pigment) in the skin. Other birthmarks are blood vessels that are bunched together or don't grow normally. It's not clear why some children have birthmarks and others don't.
a thickening of the cornea may indicate swelling swelling usually occurs from damage to the back the layer of the cornea associated with aging trauma or disease of the eye the swelling can be observed for progression or medically treated with topical hyper osmotic agents
For other uses, see Cornea (disambiguation) . The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. The cornea, with the anterior chamber and lens, refracts light, with the cornea accounting for approximately two-thirds of the eye's total optical power.In humans, the refractive power of the cornea is approximately 43 dioptres. While the cornea contributes most of the eye's focusing power, its focus is fixed.he cornea, with the anterior chamber and lens, refracts light, with the cornea accounting for approximately two-thirds of the eye's total optical power. In humans, the refractive power of the cornea is approximately 43 dioptres. While the cornea contributes most of the eye's focusing power, its focus is fixed.