THE CORNEA
The eye is enclosed by a tough white
sac, the sclera. The cornea is the transparent window
in this white sac which allows the objects you are
looking at to be carried in the form of light waves
into the interior of your eye.
The surface of the cornea is where
light begins its journey into the eye. The cornea's
mission is to gather and focus visual images. Because
it is out front, like the windshield of an automobile,
it is subject to considerable abuse from the outside
world. Particles of dust and grit inevitably find
their way onto our outer eyes and irritate them,
thereby stimulating the production of tears to wash
foreign material away.
"A minute corneal scar can
impair vision"
The cornea is masterfully engineered
so that only the most expensive manmade lenses can
match its precision. The smoothness and shape of
the cornea is as vitally important to its proper
functioning as is its transparency. If either the
surface smoothness or the clarity of the cornea suffers,
vision will become distorted.
Although appearing to be one clear
membrane, the cornea is actually composed of five
distinct layers of tissue, each with its respective
function. The thin outer layer, or epithelium, is
a reliable barrier against corneal infection and
usually must be damaged before an infectious agent
can get a start in the middle layer (stroma) of the
cornea, which is made of collagen (connective tissue).
"The cornea refracts and
protects"
We can tolerate very large scars
on our bodies with no concern except for our vanity.
Not so the cornea! Even a minor scar can impair one's
vision. No matter how well the rest of the eye is
functioning, if the cornea is scarred, clouded or
distorted, vision will be affected.
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