They say the eyes are a window to the soul. At Antietam Eye we like to say, the cornea is like the window to your eye. It forms a dome over the colored part of your eye, the iris. In between the iris and the cornea is the aqueous fluid and on top of the cornea rests the tear film. Since the cornea has no blood vessels, because it needs to be transparent, it gets all its nutrients from the aqueous and the tear film. Its shape ultimately helps determine the strength of your prescription glasses and the fit of your contact lenses. For something so thin, only 540 micrometers thick (the human hair is 50 micrometers thick) it is amazingly strong.
This little tissue is your eyes’ first defense against environmental insults. It is no wonder it is highly innervated. When the cornea is hurt, you know it! Thankfully, it is the fastest healing tissue in the body. (Whereas the tongue is the fastest healing muscle in the body.) There are five main components to the cornea. The outermost layer – the epithelium; Bowman’s membrane; the middle layer – the stroma; Descemet’s membrane and the innermost layer- the endothelium. So what can go wrong with the cornea? Many things and circumstances can cause harm and inhibit clear vision.
Injury – One of the more frequent emergencies Dr. Kornilow and Dr. Ridenour of Antietam Eye see are corneal injuries. Most common are corneal abrasions (usually the epithelium is primarily affected), or a foreign object in embedded in the cornea (Epithelium and Stroma are often involved). Always make sure to wear protective eyewear when doing things that may cause injury, such as using machinery that could cause objects to ricochet or fly or if you are in an area surrounded by dust and chemicals. Seek care immediately; remember it heals fast so if there is something embedded in there, the cornea will try to heal – this makes it harder to remove things from it.
Infection – This can be external, like a “pink eye,” or internal, like shingles. The biggest concern is to treat the infection right way. Using the wrong type of eye drop can make infections worse. For example, using an antibiotic for a viral infection, though it will not make the viral infection worse, it will not help it either. Delayed treatment will possibly allow the infection to get worse, while the wrong treatment may accelerate the infectious process.
Dry Eye – Although this is understandably an uncomfortable issue for the patient, it is equally concerning as to how it is damaging your cornea. Remember, the cornea gets nutrients from the tear film, so if none are present, essentially the cornea is receiving a poor diet.
Dystrophies – Most of the layers of the corneal consistently grow throughout our lifetime, with the exception of the endothelium. As the layers regrow, they sometimes can become hazy causing blurred vision. Occasionally the irregular regrowth can cause scratchiness and irritation. Or, in the case of the endothelium loss, it can cause the cornea to become thicker, a prominent symptom of the progressive Fuchs Corneal Dystrophy. There have been many advances that can help to alleviate the issues of corneal dystrophies, but since the cornea can continually change, a dystrophy will most likely return.
Contact Lenses – When properly used, contact lenses are an excellent way to correct your vision. Nonetheless, they can cause a lot of problems as well. Poor care can put the cornea at risk of infection. Extended wear (sleeping in them) is one of top ways to increase your chances of severe corneal damage – and one of the easiest to avoid. Contact lenses also decrease the amount of oxygen to the cornea and increase dry eye, allergic and corneal infection risk factors. It cannot be expressed enough how critical proper care of contact lenses – before during and after – is.
Keeping this amazing thin tissue healthy can give you healthy eyes that last a lifetime. We are here to help you achieve that.