Terrien Marginal Degeneration

What is Terrien marginal degeneration?

Terrien marginal degeneration (TMD) is a rare eye disease that causes thinning of part of your cornea. Over time, the condition affects your ability to see clearly.

Early detection is important to preserve or restore your vision. Treatment typically involves corrective eyewear or medication. You may need surgery to repair or replace your cornea.

How does Terrien marginal degeneration affect me?

The thinning (degeneration) of the cornea gradually worsens and leads to a flattening of the outer edge of your cornea (peripheral cornea). This causes astigmatism and blurred or distorted vision.

Terrien marginal degeneration can affect one or both eyes. Unlike some other types of corneal disease, TMD doesn’t usually involve eye pain. It may cause redness or swelling (inflammation).

Rarely, severe thinning leads to a tear (perforation) in the cornea. This may happen suddenly or when you experience eye injury or trauma.

Who does Terrien marginal degeneration affect?

Terrien marginal degeneration most often affects men and people assigned male at birth (AMAB) ages 40 or older, but it can occur at any age. People with inflammatory diseases such as rheumatoid arthritis or juvenile idiopathic arthritis may be more likely to develop the disease.

How common is Terrien marginal degeneration?

Terrien marginal degeneration is rare. Researchers don’t know how many people have the condition. French ophthalmologist Felix Terrien first described TMD in 1990.

What are the types of Terrien marginal degeneration?

Scientists believe there may be two types of Terrien marginal degeneration. The first type occurs in people over the age of 55. It slowly worsens without signs of inflammation.

The second type involves inflammation. It most often occurs in people assigned male at birth in their 20s and 30s. Healthcare providers have detected this type in people with:

• Anterior basement membrane dystrophy, an inherited (passed down in families) corneal disorder.
• Erythema elevatum diutinum, a chronic skin disease.
• Posterior polymorphous dystrophy, a rare eye disease that causes a buildup of fluid or other material in the cornea.

What are similar conditions to Terrien marginal degeneration?

• Acanthamoeba keratitis.
• Corneal ectasia, a group of conditions that change the shape of your cornea, causing astigmatism that gets worse over time.
• Corneal ulcer.
• Keratoconus.
• Marginal furrow degeneration, which causes thinning of the cornea.
• Mooren’s ulcer, a painful eye condition that causes damage to the cornea.
• Ocular rosacea.
• Pellucid marginal degeneration (PMD), a rare disease of the cornea that causes your vision to get less clear over time.
• Sclerokeratitis, which causes inflammation of the sclera and cornea.
• Vernal keratoconjunctivitis (VKC), a chronic (long-term) severe allergy that affects the eye surface.

Because the symptoms of Terrien marginal degeneration resemble other conditions, it’s important to get an accurate diagnosis. This ensures the best treatment plan for your needs.

What causes Terrien marginal degeneration?

Researchers don’t know what causes Terrien marginal degeneration. They suspect an autoimmune disease (when the immune system attacks healthy tissue) or degenerative disorder (when tissues or organs break down) may trigger TMD.

What are the symptoms of Terrien marginal degeneration?

People with Terrien marginal degeneration often don’t have any symptoms. In some cases, you may experience:

• Gradual vision changes due to astigmatism.
• Mild eye irritation due to an uneven cornea surface.

In severe cases, the cornea may puncture or tear due to injury or trauma. This is a medical emergency that can cause serious vision issues. If you experience damage to your eye, seek medical attention immediately.

How is Terrien marginal degeneration diagnosed?

Healthcare providers detect Terrien marginal degeneration with an eye exam. Accurate diagnosis helps rule out other conditions that involve corneal thinning and guide treatment.

An eye specialist (ophthalmologist) may use additional tests to see detailed images of your eye and check for changes to your cornea. These tests may include:

• Anterior segment optical coherence tomography.
• Confocal microscopy.
• Corneal topography.
• Scanning slit topography.
• Ultrasound biomicroscopy (UBM).

Is there a cure for Terrien marginal degeneration?

Terrien marginal degeneration has no cure, but treatment can help preserve vision and prevent complications. Early diagnosis enables your healthcare provider to give you the care you need.

What are the treatments for Terrien marginal degeneration?

In many cases, Terrien marginal degeneration doesn’t require treatment. Your healthcare provider may recommend “watchful waiting” and regular tests to check your condition.

If TMD affects your vision, treatment may include corrective eyewear, such as:

• Polycarbonate (hard plastic) eyeglasses.
• Rigid, gas-permeable (allows oxygen to pass) contact lenses.
• Scleral lenses, large rigid contact lenses that cover the entire cornea and correct astigmatism, helping protect the eye and improve vision.

In the case of mild inflammation, your provider may recommend eye drops, ointments or gels. They may also use topical steroids but limit their use due to the risk of increased thinning.

Will I need surgery for Terrien marginal degeneration?

In advanced cases of Terrien marginal degeneration, you may need surgery to protect, preserve or restore eye function. Your ophthalmologist may also recommend surgery when corrective lenses don’t help.

If you have severe damage to your cornea, your provider may recommend a cornea transplant with healthy tissue from a donor or an artificial (manufactured) cornea. You may have:

• Partial thickness transplant (lamellar keratoplasty) to replace part of your cornea.
• Full thickness transplant (penetrating keratoplasty) to replace your entire cornea.

How can I reduce my risk of developing Terrien marginal degeneration?

There’s nothing you can do to avoid developing Terrien marginal degeneration. But you can take measures to protect your eyes and prevent the condition from getting worse.

Try to avoid damage to the cornea by wearing protective eyewear when you:

• Clean with bleach or other chemicals.
• Do outdoor work such as lawn mowing.
• Play sports such as baseball or hockey.
• Use tools or paint.

If you wear contact lenses, follow cleaning and disinfecting instructions to prevent an eye or cornea infection. Keep appointments with your eye specialist and follow treatment guidelines to avoid complications and preserve your vision.

What can I expect if I have Terrien marginal degeneration?

Most people can manage Terrien marginal degeneration with glasses or contact lenses and regular checkups. If you have severe thinning, talk to your healthcare provider about the best options to protect your eyes and treat symptoms.

When should I seek care for Terrien marginal degeneration?

Early diagnosis of Terrien marginal degeneration is important so you can receive effective treatment. Alert your healthcare provider if you experience discomfort, pain or vision changes. Your provider can offer treatment options to give you relief and protect your sight.

A note from Cleveland Clinic

Terrien marginal degeneration is a rare condition that thins the edges of your cornea, the part of your eye that helps you focus and see clearly. Most people don’t experience symptoms. Others find that corrective eyewear helps preserve sight and avoid complications. Get regular eye checkups so that you can receive the care you need.