Corneal Disease

What is corneal disease?

The term “corneal disease” refers to a variety of conditions that affect your cornea. Your cornea is the transparent window on the front of your eye that serves as a barrier against dirt and particles. It also plays a key role in your vision. Corneal diseases can interfere with these functions and may cause pain or other symptoms in your daily life. However, some corneal diseases cause few or no symptoms but still need treatment.

If you have symptoms of corneal disease, including pain, blurry vision or sensitivity to light, see an eye care specialist right away. It’s also important to have eye exams on a regular basis, even if your eyes seem fine. An eye care specialist can tell you how often you should have exams based on your age, medical history and other factors. Your ophthalmologist will diagnose and treat corneal diseases and other eye problems to help you see clearly for many years to come.

What are the most common corneal diseases?

Many of the diseases that can affect your cornea fall into three main categories:

• Keratitis: Inflammation of your cornea that can either be infectious (microbial) or noninfectious. Infectious keratitis is called a corneal ulcer. Bacteria cause most instances of infectious keratitis. Other times, viruses, fungi and parasites may cause the issue. Many things cause noninfectious keratitis, including eye injuries and a range of conditions that dry out the surface of your eye.
• Corneal ectasia: A group of conditions that change the shape of your cornea, causing it to thin and bulge outward. Keratoconus is the most common condition within this group. Corneal ectasia sometimes occurs as a complication of certain surgeries, including LASIK eye surgery and corneal transplant. Corneal ectasia may not cause symptoms at first but then gradually affect your vision. It may lead to serious complications like corneal hydrops.
• Corneal dystrophy: A group of genetic disorders that involves abnormal deposits of proteins, fluid or other materials in one or more layers of your cornea. Some corneal dystrophies are progressive, meaning they get worse over time. Some forms also affect your vision. Fuchs dystrophy is the most common type of corneal dystrophy. Other types include epithelial basement membrane dystrophy (formerly called map-dot-fingerprint dystrophy), lattice corneal dystrophy and granular corneal dystrophy.

Other conditions that can affect your cornea

Other conditions that may cause symptoms or damage your cornea include:

• Bullous keratopathy: Swelling and blisters on your cornea’s surface. You may develop this condition after eye surgery or because you have corneal dystrophy. Symptoms are usually worse in the morning and include blurry vision and sensitivity to light.
• Corneal abrasion: An open wound on the surface of the cornea. It tends to cause blurred vision, eye pain and watering. It most commonly occurs after trauma such as a fingernail scratch but can also occur with severe dry eye disease.
• Herpetic eye disease: A painful condition that happens when a herpes virus affects your eye.
• Iridocorneal endothelial syndrome (ICE): A rare condition that causes corneal swelling and increased pressure in your eye.
• Keratoconjunctivitis: Inflammation of both your cornea and conjunctiva (the thin tissue that covers the white part of your eye and lines your inner eyelids).
• Pterygium: A growth on the white part of your eye that can extend to your cornea and, rarely, cause scarring.

What are the symptoms of corneal disease?

Symptoms vary based on the specific condition and may include:

• Eye pain, which can range from mild to severe.
• Sensitivity to light.
• The sensation that something is in your eye.
• Blurry vision.
• Vision that gets worse over time.
• Red or bloodshot eyes.
• Watery eyes.
• Pus or discharge from your eyes.

These symptoms can point to many possible conditions. And some conditions have no symptoms, especially early on. That’s why it’s important to see an eye care specialist if you experience these issues.

What causes corneal disease?

Several things may cause corneal diseases, including:

• Infection.
• Injury or trauma to your eye.
• Genetic mutations.
• Other eye conditions.
• Certain medical conditions.

What are the risk factors for corneal disease?

You may face a higher risk of certain corneal diseases if you:

• Have a connective tissue disease.
• Have a weakened immune system.
• Rub your eyes. The urge to rub may be stronger if you have hay fever or eczema.
• Undergo eye surgery.
• Wear contact lenses, especially if you wear them for longer than intended or don’t clean them properly.

How is it diagnosed?

Eye care specialists diagnose corneal diseases through a comprehensive eye exam. They’ll perform many standard tests, including a slit lamp exam, to check the health of your cornea and other parts of your eye.

Your provider may also perform a fluorescein eye stain test. This involves putting a small amount of harmless dye into your eye and then shining a light on your eye. The dye makes any scratches or damage to your cornea visible to your provider.

Your provider will tell you if they notice any problems and discuss next steps, including referrals for treatment.

How are corneal diseases treated?

Treatment options vary widely based on your condition and can include:

• Eye drops, ointments or other medications.
• Prescription eyeglasses or contact lenses.
• Laser procedures, such as phototherapeutic keratectomy (which removes tissue from your cornea to modify its shape).
• Corneal transplant surgery.
• Surgery to replace your cornea with an artificial one (keratoprosthesis).

Your eye care specialist will explain which treatment options are appropriate for you, and they’ll tailor a treatment plan to fit your needs.

Can I prevent corneal disease?

It’s not always possible to prevent corneal disease, especially since some types are genetic. But you can lower your risk of certain corneal diseases. Here are some steps you can take:

• Wear safety goggles when using equipment or chemicals that can damage your eyes. This includes yard work and using any kind of hammer, drill or saw.
• Use protective eyewear when appropriate for certain sports.
• Follow your provider’s guidance for contact lens wear, including proper cleaning and storage.
• Don’t sleep in contact lenses, even if the contact lens package recommends it.
• Don’t share eye makeup or contact lens solution with others.
• See a healthcare provider if something is stuck in your eye (rather than trying to remove it yourself).

Tell your provider if anyone in your biological family has corneal disease. This information can help your provider screen for and monitor certain conditions.

What can I expect if I have corneal disease?

Early diagnosis and treatment can help you manage your condition. Without treatment, some corneal diseases can lead to severe vision loss. That’s why it’s important to see an eye care specialist for regular checkups and tell them if you have any new or changing symptoms. They’ll tell you what you can expect in your individual situation.

When should I see my healthcare provider?

Regular eye exams are vital for your eye health. An eye care specialist can tell you how often you should have one. Most adults need an eye exam every one to two years. You may need more frequent exams if you have certain conditions or risk factors.

When should I go to the emergency room?

Seek medical care immediately if:

• You have severe eye pain.
• You have sudden changes in your vision or severe blurred vision.
• An object gets stuck in your eye.
• You experience an eye injury or trauma.

What questions should I ask my healthcare provider?

You can learn more about corneal disease (and its potential impact on you) by asking an eye care specialist:

• Am I at risk for corneal disease?
• Do I have any corneal diseases? If so, which types and how severe are they?
• Will I need treatment? If so, what will it involve?
• How can I manage symptoms at home?
• What symptoms should prompt me to call you or seek emergency care?
• What’s my outlook?
• Do you recommend genetic testing for me or anyone in my family?

A note from Cleveland Clinic

Corneal disease is an umbrella term that describes a range of conditions affecting your cornea. While some conditions can sound scary, it’s important to remember that a wide range of treatments are available to help protect your vision and restore your eye health. Talk to an eye care specialist about what you can expect going forward.