Corneal Edema

What is corneal edema?

Corneal edema is swelling in your cornea that can happen after an injury or an infection. It can also happen because of inflammation after eye surgery, including cataract surgery, or due to inherited conditions. Whatever the cause, the swelling happens after fluid builds up in your cornea.

If you have corneal swelling, you may have problems with your vision. Your cornea — the clear, dome-shaped outer layer of your eye — helps you see clearly.

How does corneal edema affect my body?

Your cornea has an inner layer of cells called the endothelium. The endothelium is responsible for pumping fluid out of your cornea, which helps maintain a certain level of hydration at all times.

Damage to the endothelium affects the pumping process. Fluid that should leave your cornea stays there because the endothelium stops working properly, causing swelling.

If you have corneal edema, you could develop folds or even breaks in a tissue called Descemet’s membrane. This membrane is part of a layer of the cornea and works to keep the cornea clear. It’s an important part of the structure of the cornea and helps to maintain stability.

What are the signs and symptoms of corneal edema?

If you have corneal swelling, your symptoms may be worse when you wake up because your eyes are closed while you sleep, keeping fluid in. Signs and symptoms of corneal edema may include:

• Eye pain or discomfort, feeling like something is in your eye.
• Blurred vision.
• Sensitivity to light (photophobia).
• Seeing halos around lights.
• Blisters (rarely).
• Corneal microcystic edema, which happens when you have very tiny blisters along with the swelling.

What causes corneal edema?

Generally, causes of corneal edema include issues with your endothelium, injuries and inflammation. In some cases, a provider can’t find a cause, which means you have idiopathic corneal edema.

Corneal diseases and other conditions can cause your cornea to retain fluid.

Eye damage, including surgery, may cause corneal edema

• Eye injuries: Eye injuries can happen because of trauma, which includes car or industrial accidents, physical fights and exposure to dangerous chemicals. Injuries can take the form of scratches, penetration or burns.
• Surgery on your eyes: Swelling is expected after most eye surgeries. Though it’s normal to have some swelling after eye surgery, it usually goes away after a couple of weeks. But in some people with preexisting conditions, the swelling may become permanent.

Eye disease may cause corneal edema

• Iritis: Inflammation of your iris.
• Keratitis: Inflammation of your cornea.
• Fuchs’ dystrophy: In this inherited condition, the cells of your cornea’s endothelium layer are no longer able to pump fluid out of your cornea. This causes swelling and may also cause blisters.
• Glaucoma: This condition causes damage to your optic nerve. It can lead to high eye pressure, which can cause swelling.

Other factors that can cause corneal edema

• Taking some medications.
• Wearing contact lenses that are too tight.
• Infections.

How is corneal edema diagnosed?

To diagnose swelling of your cornea, an eye care specialist will first ask you questions about your symptoms and medical history. They’ll give you a complete eye exam and use magnifying equipment to be able to see your cornea.

A provider may also measure the thickness of your cornea using a test called pachymetry. They may also use ultrasound to assess your eyes.

Another test you may have is optical coherence tomography of the anterior segment of your eye, which is the part of the eye that contains your cornea. This type of test uses reflected light to assess your eye health. It’s not invasive.

How is corneal edema treated?

A healthcare provider will treat corneal edema and any condition that’s causing or contributing to the swelling. In some mild cases, corneal edema can resolve on its own.

Nonsurgical treatments for corneal edema

Your provider may recommend topical items (applied directly to your eye) or other forms of medications, like pills or shots, including:

• Antibiotics for infections.
• Corticosteroids for inflammation.
• Hypertonic solutions to encourage dehydration of your cornea.
• Topical treatments for glaucoma to reduce eye pressure.
• Bandage contact lenses to provide relief for blisters.

Surgical treatments for corneal edema

• Surgery to transplant a new cornea, either partial or full thickness if there’s severe scarring.
• Surgery to reduce eye pressure from glaucoma.

How can I reduce my risk of developing corneal edema?

You may be able to reduce your risk of corneal edema by taking care to protect your eyes while working or participating in sports. Wear protective gear while riding a motorcycle or bike and while working.

Getting regular eye exams as recommended by a provider can help you find issues early.

Managing health conditions can help, especially if they’re conditions that can cause corneal edema.

Follow your provider’s instructions on how to clean your contact lenses and how long you should wear them.

What can I expect if I have corneal edema?

The prognosis (outlook) for most cases of corneal edema is generally good if you get treatment for the edema and the underlying conditions.

When should I see a healthcare provider?

Contact a healthcare provider if you have symptoms that affect your vision or that cause discomfort or pain.

If you have an eye condition, follow the suggestions of your eye care provider on how often to make appointments and how to take your medications.

A note from Cleveland Clinic

Corneal edema, or corneal swelling, can be quite uncomfortable. If your eyes hurt or if you’ve had eye surgery, contact your eye care provider. You may have another condition that needs treatment. Getting medical help early is likely to bring the best results. Your vision is important to you and to your healthcare team members.