Normally, your cornea— the clear outer lens or "windshield" of your eye — has a dome shape, like a ball. Sometimes, the structure isn’t strong enough to hold its round shape and bulges outward, like a ...

Doctors classify keratoconus into stages based on how much the cornea has thinned and changed shape. While there are a few staging systems, one common method classifies it from mild to severe.

The eye is a complex organ made up of several layers. The first is the conjunctiva which covers the sclera, also known as the white of the eye. The next is the cornea, a clear dome-shaped layer of ...