What is the cornea and how does it work?
The cornea is the clear dome that makes up the front of your eye. Normally, when looking straight on at the eye, you look right through the cornea and see the colored iris and black pupil of the eye. From the side view of the eye, you can best see the clear dome of the cornea. The cornea is only about 1/20th of an inch thick (550 microns) and is made up of three main layers of tissue. They are the following: 1. The surface epithelial layer: This is the layer that is on the surface, like the skin of the eyeball, and is about 6 cell layers thick. It is the layer that easily heals and replaces itself when injured such as after a corneal abrasion. There is a lot of pain with an abrasion because the corneal nerves lie just below the surface and are exposed when there is a break in the corneal epithelial layer. The epithelial layer of the cornea must be perfectly smooth and clear in order to provide for good focusing of light and good vision. 2. The central corneal stroma layer: This layer o
