What is the Cornea?
The cornea is the clear dome-shaped layer at the very front of the eye. The most important function of the cornea is help us see clearly by focusing the light that comes into the eye. The lens refocuses that light onto the retina, which begins the process of changing light into vision. The cornea’s multiple layers also help protect the eye from germs, bacteria, and damaging UV light from the sun.
Common Diseases and Conditions of the Cornea
Allergies
Allergies, especially from pollen, can cause uncomfortable symptoms in the eye including redness, itching, burning, tearing, and discharge. Antihistamine eyedrops usually relieve these symptoms.
Blepharitis
Blepharitis is a common condition that causes inflammation of either the inner or outer eyelids. Either type of blepharitis can cause red or swollen eyelids, burning or itching sensation in the eye, crusting of the eyelids, and other eye discomfort. Complications can include the development of a stye or a chalazion.
Treatment for blepharitis involves keeping the lids clean and free of debris. Apply a warm compress to the lid and scrub the eyelid lightly with a cotton swab, water and baby shampoo. For severe cases of blepharitis, your eye care professional may prescribe antibiotics or steroid eyedrops.
Conjunctivitis
Conjunctivitis is a common disorder that affects millions of adults and children each year. It can be caused by bacterial or viral infections, as well as allergies and exposure to irritants. It is commonly known as “pink eye” because the inflammation makes blood vessels more visible and gives the eye a reddish appearance.
Conjunctivitis can be highly contagious and can recur or infect others if proper steps are not taken to control the spread of infection. Most conjunctivitis resolves on its own, however, bacterial conjunctivitis must be treated with antibiotic eyedrops or ointment.
Dry Eye
A normal eye is kept moist by blinking, which spreads a tear film over the eye. Dry eye is an uncomfortable condition that occurs when the eyes do not create enough tears, or do not create the right type of tears or tear film. This can cause symptoms such as burning, redness or a scratchy feeling.
Since there are a wide variety of causes for dry eye, it’s important for your eye doctor to diagnose the underlying problem. Treatment can include lifestyle changes, over the counter and prescription eyedrops, punctal plugs, and surgery.
Fuch’s Dystrophy
Fuch’s dystrophy is a slowly progressing disease that usually affects both eyes and causes vision deterioration over time. Symptoms include glare, blurred or distorted vision, halos, and painful or tiny blisters on the surface of the cornea.
The first step to treat Fuch’s dystrophy is to reduce swelling with drops, ointments, or soft contact lenses. For severe cases, a corneal transplant may be recommended.
Keratoconus
This is a corneal dystrophy condition in which the cornea gradually thins and develops an abnormal curvature. It usually affects both eyes. It can cause blurry or double vision, difficulty with distance vision, and sensitivity to light.
Initially, keratoconus is corrected with glasses or soft contact lenses. Specially fitted contact lenses may be required to correct the distortion of the cornea. In most cases, the problem resolves after a few years. A small number of patients who develop corneal scarring may require a corneal transplant.
Pterygium
A pterygium is a pinkish wedge-shaped growth on the cornea, which usually begins near the nose. Although It is a benign growth, it can sometimes enlarge enough to interfere with vision. Doctors believe that excessive exposure to the sun’s UV rays may be a cause. Wearing a wide-brimmed hat and sunglasses helps protect against pterygium.
Your doctor may recommend lubricating eye drops to reduce redness and irritation associated with pterygium. Surgery is not usually recommended because the pterygium may grow back, especially in younger adults.
Uveitis
Uveitis is a general term that refers to a variety of diseases that cause inflammation. Most of these diseases affect the uvea, which is the middle part of the eye, but they can also affect other parts of the eye and body. These inflammatory diseases cause swelling, which can damage eye tissue. Uveitis can be a short-term or a chronic condition, and its impact on vision can range from mild to severe. Uveitis in the front or middle of the eye is usually treated with eye drops to reduce inflammation.
Corneal Treatments
There are a wide variety of treatments for corneal disease, including medicated eye drops, procedures, and surgery.
Corneal transplantation surgery may be recommended if the cornea cannot be healed or repaired with medications or other procedures. Depending on the severity of the problem, part or all the diseased tissue is removed and replaced with healthy corneal tissue.