Keratoconus - Symptoms, Risk factors and Treatment

Keratoconus is a condition in which the cornea becomes thin over time and bulges out like a cone. The cornea is a transparent layer present in front of the eye that functions as the lens and helps in the refraction of light rays coming towards the eye.

What causes keratoconus?

The exact cause of keratoconus is unknown. However, certain factors are believed to be associated with the development of keratoconus such as:

Genetics: There is a greater chance of developing keratoconus in people with a family history of it. It indicates that genes play an important role in this condition.

Rubbing the eyes: Rubbing your eyes over time harshly may result in keratoconus and can also cause the condition to worsen.

Certain illnesses: Certain health conditions are found to be associated with keratoconus, such as:

• Down syndrome
• Retinitis pigmentosa
• Ehlers-Danlos syndrome
• Allergic rhinitis
• Hay fever
• Asthma

Race: Black people are more likely to develop keratoconus than white people.

Symptoms of keratoconus:

The symptoms of keratoconus include:

The symptoms of keratoconus vary depending on the stage and progression of the condition. In earlier stages, the symptoms may just look similar to normal refractive error like myopia or nearsightedness. Over time the symptoms may worsen such as:

• Blurred vision
• Double vision
• Photosensitivity- Increased sensitivity to light
• Sudden clouding of vision
• Need for changes in eyeglasses power often
• Trouble in nighttime driving

Diagnosis of keratoconus:

Keratoconus is diagnosed by a history and different examinations. Your ophthalmologist may ask questions related to any previous problems related to the eye and family history of keratoconus. For further evaluation, your ophthalmologist may perform tests such as:

Eye refraction: In this test, your ophthalmologist will ask you to look through a device called a phoropter or may ask you to see a chart on the wall with different lenses to check for any refractive errors.

Slit-lamp examination: A slit-lamp comprises a microscope along with a beam of light which helps the doctor get a detailed view of different structures in the eye. Your doctor may ask you to sit in front of the slit lamp, and then they will focus the slit lamp on the eye. It will involve focusing on a high-intensity beam of light towards your eye. This light is high in intensity but not harmful to the eyes.

Keratometry: Keratometry involves the use of an instrument called a keratometer. This instrument helps in determining the corneal curvature (radius of curvature of the cornea) and power of the cornea. 

Corneal topography: Also known as photokeratoscopy, this test involves detailed mapping of the corneal curvature with the help of a computer. It can also detect the thickness of the cornea and can help in the early detection of keratoconus.

Treatment of keratoconus:

The treatment of keratoconus depends on how advanced the condition is and how it's progressing. Initially, your doctor may suggest eyeglasses. A new pair of glasses can help correct the condition. If glasses do not work, your doctor may suggest contact lenses.

Cornea collagen crosslinking is a treatment strategy that may be used for slowing or stopping the progression of keratoconus. In severe cases, your doctor may suggest corneal transplant surgery to correct the condition.

Conclusion:

Keratoconus is a condition in which the shape of your cornea becomes changed that can affect the vision and be bothersome. Family history tends to play a role in developing keratoconus. If you have a family history of keratoconus, it is advisable to consult your ophthalmologist to prevent this condition.