What is the Cornea?
The cornea is the clear front dome that covers the front part of the eye, and through which all the light must pass in order to make it to the inside of the eye. The cornea is an extraordinary structure, which remains clear, in the absence of illness and injury, for the whole of your life.
The cornea is the most important refracting surface in the eye, in other words it is the one that produces most of the important focusing of light so that you can get clear vision.
The cornea can become injured, either perforated or lacerated with sharp injuries, damaged with blunt injuries, or with chemical injuries or burns. Although the cornea has capacity to heal, mostly the healing process reduces the clarity of the cornea and makes it less useful for getting clear vision.
The cornea is remarkable in that its clarity is created by relative dehydration. This is in spite of the fact that it contains the watery inside of the eye behind it and tears in front of it, but many of the structures keep water from entering the cornea and making the cornea disorganised and opaque. Loss of the barrier functions in the front or behind make the cornea swell and make it lose clarity, and the eye lose sight.