KERATOCONUS TREATMENTS

• Contents

1 What is Keratoconus?
1.1 What Causes Keratoconus? What are the Risk Factors?
1.2 What Are the Symptoms of Keratoconus?
1.3 How is The Disease Diagnosed?
1.4 How is Keratoconus Treated?
1.5 Corneal Crosslinking Treatment
1.6 Hybrid Treatment Method

Although the exact cause of keratoconus is not known, some scientific studies reveal that genetic factors play a major role in the development of the disease. Therefore, people with a family history of keratoconus should have regular doctor check-ups.

In addition, during the development of the disease, imbalances in the enzymes in the cornea are observed. As a result, the cornea becomes more vulnerable to oxidative damage and tapers forward with the thinning of its surface.

The risk factors for the formation of the disease are as follows:

• Some inherited diseases such as Down Syndrome, Osteogenesis Imperfecta, Marfan Syndrome.
• Pollinosis in childhood and constant rubbing of the eyes are risk factors for the triggering of keratoconus disease in people with sensitive corneal structure.
• The use of contact lenses that are not compatible with the eye can trigger the disease by creating a degenerative effect on the cornea.
• Congenital eye anomaly,
• Being exposed to UV rays without protection in daily life,
• Low level of collagen in the cornea,
• Night blindness (chicken black) disease,
• Chronic eye irritation.

Keratoconus symptoms are usually noticed late. The progression of the disease occurs slowly over a wide period of time. Vision decreases in patients over time. Vision quality cannot be permanently improved with glasses and contact lenses, but the quality of vision can be improved. Despite the low level of symptoms in the early stages of the disease, the possibility of early diagnosis and treatment arises due to its slowly progressive nature.

Among the symptoms of keratoconus, observed in the first stage is the development of irregular myopia and astigmatism in patients at the same time as the change in the shape of the cornea. Astigmatism occurs when the cornea protrudes from a smooth and rounded shape to a cone shape.

The progression of the disease usually takes years. In some cases, the course may suddenly accelerate and worsen. The cornea may swell suddenly and a permanent hardening condition called scarring may occur. With the appearance of this scar tissue called scar, the cornea loses its clarity and smoothness. As a result, the process of blurring and disorder in vision occurs rapidly.

If the disease is not followed up and the necessary precautions are not taken on time, excessive thinning and edema of the cornea may occur. In the last stage, where the patient’s vision gradually disappears, the need for corneal transplantation (keratoplasty) may arise.

Keratoconus symptoms include:

• Mild blurring of vision in the initial stage, severe blurring of vision in advanced stages,
• Ripples and curvatures in the appearance of straight lines,
  Frequent advances in eye numbers,
• Glare and seeing halos in luminous objects,
• Double vision and image proliferation when looking with one eye,
• Impaired night vision and difficulty driving at night,
• Eye allergy or itching,
• The contact lens used in the past is not fully inserted into the eye,
• Blurred vision after a while, despite frequent glasses change and glasses use.

Keratoconus can be difficult to diagnose in the early stages. It can be detected by routine eye doctor examination in people with symptoms of the disease in their family’s health history.

If problems such as a continuous increase in the degree of eye disorders and allergic conjunctivitis are accompanying the disease in the 10-20 age group, the diagnosis can be made by considering the risk of the disease. The diagnosis of the disease can be made by detailed eye examination and corneal topography.

The corneal topography (surface map) reveals the map of the corneal surface in detail, revealing in detail whether there is a thinning of the surface and the changes that can occur in the shape of the cornea. Other tests may also be used for diagnosis. These tests may consist of the following:

• Eye Refraction Test,
• Slit Lamp Inspection,
• Keratometry,
• Corneal Topography.

Keratoconus treatment is a multi-stage treatment. Although early diagnosis is important in treatment, there may be different treatment options for the initial and advanced stages of the disease.

In the first stage of the treatment process, the patient is told how the treatment process will be and what the patient should do during this process. Thus, risk factors are minimized. Glasses or soft contact lenses may be prescribed to the patient, depending on the eye grade.

For the early stage, scleral or rigid gas-permeable lenses can be used for treatment. These lenses improve vision, but they cannot definitively stop the progression of the disease. These lenses need to be used continuously and they can slow the progression of the disease as long as they are used continuously. The disease usually progresses more rapidly after the use of lenses is discontinued.

If the keratoconus has progressed despite taking the necessary precautions, that is, if the cornea becomes thinner and steeper and the patient’s eyeglasses degree increase, Corneal Cross Linking Treatment is applied. It is the most powerful treatment method that can stop the progression of the disease. It is generally preferred by young people and women before pregnancy.

In Corneal Cross-linking Treatment, it is aimed to strengthen the collagen and fibrils in the cornea by cross-linking by using riboflavin, that is, vitamin B2 and UV A rays. It is applied in operating room conditions. With this treatment, thinning and anterior bowing of the cornea can be stopped.

Vision loss is stopped in almost all of its patients, and it also improves the quality of vision in the vast majority of them. The last stage of this treatment is to eliminate the refractive error caused by the change in the corneal structure, such as myopia and astigmatism.

Another method used for the treatment of keratoconus is hybrid therapy. The hybrid therapy was developed by New York University. In this treatment, the irregularity on the corneal surface is removed with a no touch laser, and the cornea is strengthened with vitamin B2 + ultraviolet light therapy applied in the same session. Thus, the progression of the disease is stopped. The person can receive both Cross Linking, which helps to stop the disease, and laser treatment, which improves vision, in the same session.

Corneal transplantation is performed in very advanced keratoconus patients in whom the disease is recognized late or does not respond to any treatment. In corneal transplantation, the damaged corneal tissue of the eye is replaced with a healthy corneal tissue. The success rate of corneal transplantation is very high and it is applied as a full or half layer.