Author : Dr Sinchana Adyanthaya , MBBS, MS, Fellowship in Cornea and Refractive surgery, Assistant Professor , Department of Ophthalmology, BGS Medical College & Hospital.
Keratoconus is a condition that affects the cornea, the transparent front part of the eye. It is a progressive disorder in which the cornea thins and begins to bulge outward into a cone-like shape. This irregular shape can lead to distorted vision, making it difficult for individuals to see clearly. While keratoconus can be alarming, early diagnosis and appropriate treatment can help manage the condition and significantly improve the quality of life for those affected.
In this blog, we will explore the causes, symptoms, diagnosis, and treatment options for keratoconus, as well as how individuals can cope with living with the condition.
What is Keratoconus?
The cornea plays a vital role in focusing light onto the retina at the back of the eye. When the cornea is healthy, it has a smooth, round shape, allowing light to enter the eye evenly. In individuals with keratoconus, the cornea thins and weakens, which causes it to bulge into a cone shape. As a result, the shape of the cornea becomes irregular, disrupting the way light is focused on the retina.
This irregular shape leads to various visual disturbances, including blurred vision, distortion, and increased sensitivity to light. As the condition progresses, the symptoms can worsen, affecting a person’s ability to perform everyday tasks.
Causes of Keratoconus
The exact cause of keratoconus remains unclear, but several factors may contribute to its development:
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Genetics: There is a genetic predisposition to keratoconus. If a close family member, such as a parent or sibling, has the condition, the chances of developing keratoconus are higher. However, not everyone with a family history of the condition will necessarily develop it.
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Environmental Factors: Some environmental factors, such as frequent eye rubbing, may exacerbate the condition. Rubbing the eyes can put undue pressure on the cornea, leading to further thinning and progression of keratoconus.
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Medical Conditions: Certain medical conditions may increase the risk of developing keratoconus. These include Down syndrome, Ehlers-Danlos syndrome, and other connective tissue disorders. People with these conditions may be more susceptible to corneal instability and thinning.
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Hormonal Changes: Hormonal changes, particularly during puberty and adolescence, may play a role in the onset or worsening of keratoconus. The condition often begins in the late teens or early twenties and may stabilize later in life.
While the exact cause is still under study, it is widely believed that a combination of genetic, environmental, and medical factors contributes to the development of keratoconus.
Symptoms of Keratoconus
The symptoms of keratoconus can vary from person to person, and they typically develop slowly over time. Some of the common symptoms include:
● Blurred or distorted vision: As the cornea becomes more irregular, vision becomes blurry, and straight lines may appear wavy or distorted.
● Increased sensitivity to light: People with keratoconus may experience heightened sensitivity to bright lights (photophobia), especially at night.
● Frequent changes in eyeglass prescription: Those with keratoconus may find that their vision deteriorates rapidly, leading to frequent changes in their prescription glasses or contact lenses.
● Ghosting or double vision: As the cornea becomes more irregular, some individuals may experience ghosting or seeing multiple images of a single object.
● Eye irritation: Keratoconus may cause discomfort or a feeling of something being in the eye, particularly if the cornea has become very thin.
In the early stages, the symptoms may be subtle and difficult to detect. However, as the condition progresses, the visual disturbances can become more noticeable, and individuals may require more frequent eye exams to monitor the progression of the disease.
How Is Keratoconus Diagnosed?
Diagnosing keratoconus typically involves a thorough eye examination conducted by an ophthalmologist or optometrist. Several tests are used to assess the shape and thickness of the cornea, as well as the degree of visual impairment. These tests may include:
● Corneal topography: This imaging test maps the surface of the cornea, highlighting any irregularities in its shape. It is one of the most effective tools for diagnosing keratoconus and monitoring its progression.
● Pachymetry: This test measures the thickness of the cornea. Thinning of the cornea is a hallmark of keratoconus, and pachymetry helps to determine the extent of thinning.
● Slit-lamp examination: A slit-lamp is a microscope that allows the doctor to examine the cornea and other parts of the eye in detail. This test can help detect signs of keratoconus, such as corneal scarring and irregularities.
● Retinoscopy: This test helps the doctor evaluate how light is reflected from the retina, providing additional information about the degree of vision distortion caused by keratoconus.
If you experience any of the symptoms associated with keratoconus, it is important to see an eye doctor as soon as possible. Early detection can help prevent further deterioration of vision and ensure timely treatment.
Treatment Options for Keratoconus
While there is no cure for keratoconus, various treatment options can help manage the condition and improve vision. The appropriate treatment will depend on the severity of the disease and the individual’s specific needs. Some common treatment options include:
1. Eyeglasses and Contact Lenses
In the early stages of keratoconus, eyeglasses or soft contact lenses may be sufficient to correct vision. However, as the condition progresses and the cornea becomes more irregular, these options may become less effective. For many people with keratoconus, rigid gas permeable (RGP) contact lenses or scleral lenses are necessary to improve vision.
● Rigid gas permeable (RGP) lenses: These lenses are custom-made to fit the shape of the cornea. RGP lenses help smooth out the irregularities of the cornea, improving vision.
● Scleral lenses: These larger lenses rest on the sclera (the white part of the eye) and create a smooth surface for light to pass through. They are often used for more advanced cases of keratoconus.
2. Corneal Cross-Linking (CXL)
Corneal cross-linking is a relatively new treatment option that aims to halt the progression of keratoconus. This procedure involves using ultraviolet (UV) light and a special riboflavin solution to strengthen the collagen fibers in the cornea. This can help stabilize the cornea and prevent further thinning and bulging. Cross-linking is typically performed in the early to moderate stages of keratoconus and is effective in slowing or stopping disease progression.
3. Intacs
Intacs are small, curved inserts that are surgically placed into the cornea to help reshape it. These inserts can improve vision by reducing the cone-like bulging of the cornea. This treatment is typically used in the early stages of keratoconus or in cases where cross-linking has not been effective.
4. Corneal Transplant Surgery
In severe cases of keratoconus, where the cornea becomes excessively thin and scarred, a corneal transplant may be necessary. In this procedure, a damaged cornea is replaced with a healthy donor cornea. Corneal transplants are typically reserved for cases where other treatments have not been successful in restoring vision.
Coping with Keratoconus
Living with keratoconus can be challenging, particularly as the condition progresses and vision becomes more impaired. However, many people with keratoconus can lead fulfilling lives with the right support and treatment. Here are some strategies for coping with the condition:
● Regular eye exams: It is essential to have regular check-ups with your eye doctor to monitor the progression of keratoconus and adjust treatment as necessary.
● Use the right corrective lenses: Wearing the appropriate eyeglasses or contact lenses can significantly improve vision and help with everyday activities.
● Stay informed: Educate yourself about the condition, treatment options, and new developments in keratoconus care. Understanding the disease and being proactive about treatment can empower you to take control of your eye health.
● Join a support group: Connecting with others who have keratoconus can provide emotional support and helpful insights. Many online communities and local support groups exist for people with eye conditions.
Conclusion
Keratoconus is a condition that can significantly affect a person's vision and quality of life, but with the right treatment and management strategies, individuals with the condition can lead active and fulfilling lives. Early detection, regular eye exams, and prompt intervention can help slow the progression of the disease and improve vision.
If you suspect that you have keratoconus or have been diagnosed with the condition, it’s important to work closely with an eye care professional to explore your treatment options. With advances in treatment, people with keratoconus now have more tools than ever before to manage the condition and maintain their vision for years to come.
