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Your eye is a complex organ made of many intricate and sensitive tissues, muscles, and fibers. It uses some of these to turn light entering your eye into usable information for your brain to process.

The retina, for example, contains millions of different types of photosensitive cells. And some of them are photosensitive in entirely different ways.

The retina is incredibly delicate and a crucial part of being able to see. On the other hand, the cornea is one of the simpler parts of the eye but is no less essential to your vision.

Keep reading to learn more about the cornea and the role it plays in your vision.

What Does The Cornea Do?

The cornea is the transparent tissue at the front of your eye, covering the pupil and iris. It acts as a physical barrier between the outside world and the more delicate parts of your eye.

Acting as a barrier, it keeps out dirt, bacteria, and other harmful things. Another equally important function of the cornea is to focus the light that passes through it onto your retina.

The cornea is not the only part of the eye that does this, but it focuses most of the light entering your eye. The lens behind your cornea performs more fine-tuned focusing, but the cornea does a bulk of the work.

It is a vital component to clear eyesight. When you undergo a vision correction procedure like LASIK, your cornea gets reshaped, which allows it to function more optimally.

How Durable Is Your Cornea?

The cornea is not only more straightforward than other parts of your eye, but it is also more durable. A normal cornea is only about half a millimeter thick, but it’s capable of regenerating itself.

And despite how thin the cornea is, it contains five layers. The top layer is the epithelium.

It is only about five cells thick and is continually recycling itself. The cells in the epithelium turn over within a single week.

The middle layer of the cornea is the stroma. It’s connected to the epithelium by Bowman’s layer.

Bowman’s layer is a thin but dense sheet of fibrous tissue. The stroma is the thickest of all five layers, making up about ninety percent of the cornea’s thickness.

The endothelium is the bottom layer of the cornea and separates the cornea from the iris and pupil. Connecting the endothelium and the stroma is a fragile tissue called Descemet’s membrane. Descemet’s membrane triples in size by the time you are an older adult. 

Potential Corneal Problems

The cornea may act as a protective barrier, but it also is susceptible to problems that can impact your sight. If your cornea is not curved correctly, for example, it doesn’t refract light onto your retina.

This error results in a refractive error like nearsightedness, farsightedness, or astigmatism. Physical trauma to the eye can lead to abrasions and scarring of the corneal tissue as well.

There are even infections that create corneal ulcers, and the cornea can suffer from diseases like keratoconus. While it is a durable protective layer, there are also plenty of issues that affect your cornea.

Schedule an appointment at Colorado Eye Consultants in Littleton, CO, to keep your corneas and vision healthy!