Terrien Marginal Degeneration - Causes and Its Management

What Is Terrien Marginal Degeneration?

Terrien marginal degeneration (TMD) is a less common eye condition that affects the cornea. The characteristic feature of this condition is corneal thinning. The cornea receives the light which passes through the iris and hits the lens, and the light rays are focused on the retina. This condition affects a person's vision to a great extent. Early recognition is essential to safeguard or reestablish the image. Treatment commonly includes prescribing eyeglasses, medication, or surgery. One may also require surgery to replace the cornea.

Who Is at a Greater Risk of Terrien Marginal Degeneration?

Terrien minimal degeneration most frequently influences men and individuals allowed male upon entering the world (AMAB) than women at a ratio of three ratio one and affects people of age 40 or more established; however, it can happen at any stage in life. Individuals with incendiary illnesses, for example, rheumatoid joint pain or adolescent idiopathic joint inflammation, might be bound to foster the sickness.

What Are the Types of Terrien Marginal Degeneration?

There are two types of Terrien’s marginal degeneration,

• The first type occurs in people over the age of 55 years and worsens with age without any signs and symptoms of inflammation.

• The second type occurs in males aged 20 to 30 and involves inflammation. This variant is seen in people affected with,

  • A genetic corneal disorder called anterior basement membrane dystrophy.

  • A long-term skin disorder called erythema elevatum diutinum.

  • A rare eye condition that is caused due to accumulation of fluid or other substances is called posterior polymorphous dystrophy.

What Are the Causes of Terrien Marginal Degeneration?

The cause of this condition is unknown. TMD is believed to be caused due to an autoimmune disease or degenerative condition.

What Are the Symptoms of Terrien Marginal Degeneration?

People with TMD do not have any apparent symptoms. In some conditions, a person may experience symptoms such as

1. Changes in Vision: There may be changes in vision due to astigmatism that may be caused due to thinning of the cornea.

2. Irritation of the Eyes: The eyes may be irritated due to uneven surfaces. Since the cornea may not thin regularly, it may cause uneven eye surfaces.

What Conditions Are Similar to Terrien Marginal Degeneration?

The eye conditions that may be similar to that of TMD are

1. Ameboeic keratitis is a rare eye infection that can result in permanent vision loss.

2. Ulcers of the cornea are infections caused due to bacteria, viruses, parasites, or fungi.

3. Keratoconus, weakening of the cornea.

4. Sclerokeratitis is primarily seen in men and is characterized by foreign body sensation, redness, and infection.

How Does Terrien Marginal Degeneration Affect the Eye?

The Terrien marginal degeneration can affect the eye in the following ways:

• Astigmatism: Due to the thinning of the cornea, the outer edge of the cornea tends to flatten. This can cause astigmatism, which may also be a blurring of vision.

• Inflammation: TMD can cause inflammation and its associated eye symptoms. It may cause redness, blurring, and redness of the eyes. This condition, however, does not cause pain in the eye.

• Injury: Any sudden damage can cause tearing of the cornea. This can happen all of a sudden.

How Is Terrain Marginal Degeneration Diagnosed?

The condition of Terrien marginal degeneration is diagnosed by performing various eye tests. It can be analyzed even using routine eye examinations. An ophthalmologist performs these tests. Various other tests are also performed that produce a detailed eye image. The different diagnostic tests that can be performed include

• Anterior Segment Optical Coherence Tomographic Method: It is a test used to view the anterior structures of the eye. This can be used to diagnose various corneal disorders.

• Confocal Microscopy: This is a laser microscope for visualizing the eye structure. This type of image helps in contrasting photos.

• Corneal Topography: This test is used to map the structures of the cornea. This gives a three-dimensional view of the cornea.

• Scanning Slit Topography: This test helps in measuring corneal thickness.

• Ultrasound Biomicroscopy: This particular test visualizes the eyes' internal structures.

There is no specific laboratory test. Terrien's marginal degenerative condition is clinically diagnosed by

• Lack of inflammation in the eye.

• Occurrence of superficial vascularization.

• It increased liner lipid deposition.

• Lack of defect in the epithelium.

• Slow progression.

• No related systemic condition.

How Is Terrien Marginal Degeneration Treated?

Terrien's marginal degeneration has no treatment. It can only be managed. Terrien's borderline degeneration treatment aims at preserving the vision. Terrian borderline degeneration treatment works well if an early diagnosis is made. The treatment is done through regular testing and close monitoring of the situation. The various treatment options for TMD include:

• Prescribing Eyeglasses: A doctor may prescribe eyeglasses for correcting vision. The doctor may prescribe polycarbonate eyeglasses for this purpose. This protects the eye from UV (ultraviolet radiation) and reduces damage.

• Prescribing Contact Lenses: The doctor may prescribe contact lenses for the condition. Rigid and oxygen-permeable lenses are defined for this condition. This can help with vision at the same time, protects the cornea from ulcerations and damage.

• Scleral Lens: The scleral lens is similar to contact lenses but more significant than that. They help in covering the entire surface of the cornea. They protect the cornea at the same time and help with restoring the vision also.

• Eye Drops: The doctor may prescribe eye drops in case of acute symptoms of the condition, such as redness and infection.

• Steroids: The doctor may also prescribe steroids for managing the condition. But the usage of steroids is limited as they can sometimes cause cornea thinning.

• Surgery: Advanced cases of TMD may need surgery. In advanced cases, there may be severe damage to the cornea. This can be managed with a cornea transplant. A corneal transplant can be from a donor's eye or an artificial source. The types of transplants may include:

1. Full-Thickness Transplant: In this procedure the entire thickness of the cornea is replaced.

2. A Partial Thickness Transplant: It is also known as lamellar keratoplasty, in which only a part of the cornea is replaced.

What Is the Differential Diagnosis of Terrien's Marginal Degenerative Condition?

• Collagen vascular disease, which causes long-term inflammation of the connective tissue.

• Dellen, thinning of cornea or sclera.

• Marginal furrow degeneration condition, which is a circumferential thinning of the cornea.

• Sclerokeratitis the presence of foreign body sensation and irritation.

• Mooren's ulcer is a painful corneal ulcer.

• Infectious corneal ulcer.

• Keratoconjunctivitis sicca, dryness of the conjunctiva and cornea.

• Staphylococcal marginal keratitis is a condition caused due to immune reaction.

Conclusion

TMD is a rare condition of the eye. It can occur to anyone. It may have symptoms like blurring of vision and visual disturbances. Mostly they do not have any symptoms. Hence, the condition takes a while before showing signs. Periodic regular eye check-ups can diagnose such Conditions before it progresses. Thus, a routine eye examination can help diagnose these conditions immediately.