The cornea is the transparent front surface of your eye mainly responsible for focusing light. Keratoconus causes the cornea to gradually thin and become more conical in shape, causing loss of focus and deterioration of vision.
The cause of keratoconus is currently unknown. The disease appears to be genetically predisposed, with approximately one in ten people with keratoconus having a parent with keratoconus.
Keratoconus is also connected to:
- eye allergies;
- excessive rubbing of eyes;
- connective tissue disorders, such as Marfan syndrome.
Keratoconus often starts to develop in people in their late adolescence or early twenties. The condition is progressive and vision usually deteriorates over 10 to 20 years.
Symptoms of keratoconus
As a rule, keratoconus affects both eyes at the same time and vision problems can occur when looking both near and far. Different eyes may experience different symptoms, which may also change over time.
The symptoms of early-stage keratoconus may include:
- slight blurriness of vision;
- distortions in vision (straight lines seem curved and wavy);
- increased sensitivity to light;
- redness, swelling of eyes.
The symptoms of more advanced stages of keratoconus may include:
- blurry and severely distorted vision;
- rapidly changing myopia or astigmatism that requires frequent renewal of an eyeglass prescription.
Keratoconus usually progresses slowly and it can take years for any changes to occur. However, for some people, changes in vision may also be rapid. Rapid progression of the disease may cause sudden corneal swelling and scarring. As a result of scarring, the cornea loses its smoothness and becomes more opaque. This causes vision to become even more distorted and blurred.
Diagnosis and treatment
Keratoconus can be diagnosed during a routine eye examination where the anterior surface of your eye is examined and the curvature of the cornea measured. Corneal topography, which allows the mapping of different parts of the corneal curvature, is also used to diagnose the disease.
Specific treatment depends on the severity of the symptoms. In the case of mild symptoms, vision can be corrected with glasses. In later stages, when glasses no longer help, special hard contact lenses can be used to help maintain focus.
In addition to the above, the following methods are used for keratoconus treatment:
- Collagen cross-linking. The aim of the procedure is to strengthen the cornea of the eye by the use of UV radiation and special eye drops, thus preventing the condition from progressing further.
- Cornea transplant. If the cornea has been stretched very thin, it will be partially or completely replaced with a donor cornea.
It is very important to avoid rubbing your eyes. This could cause further damage to your cornea and make the symptoms worse.