What is keratoconus?
Keratoconus is an eye disease whereby a gradual thinning of the central or paracentral area of the cornea occurs. Due to this thinning, the usually spherical cornea becomes conical in shape causing an irregular astigmatism that distorts images and causes a gradual loss of vision.
Keratoconus is generally bilateral although one eye may be more affected than the other.
It generally appears in adolescents and young adults.
What causes keratoconus?
The cause is unknown. In some cases it may be hereditary although many patients with keratoconus have no family members with the disease. Keratoconus is passed from parents to children in 25% of cases. The remaining cases appear sporadically. Persistent light damage to the structure of the cornea, such as excessive eye rubbing, is also known to be a possible cause of keratoconus.
On occasions keratoconus is associated with other conditions such as atopic keratoconjunctivitis, Down’s syndrome and Marfan syndrome.
What are the symptoms of keratoconus?
Some light cases of the condition do not distort vision at all and are only diagnosed through corneal topography studies.
The main symptoms are a reduction in sight and the appearance or sudden increase in astigmatism. Therefore, it’s important that any patient experiencing a sudden increase in their astigmatism (particularly children and young adults) visit their ophthalmologist to check for keratoconus.
Can keratoconus be prevented?
Nothing can be done to prevent keratoconus but there are treatments to slow it down. An early diagnosis is fundamental to stop the condition developing and becoming a serious condition that requires more aggressive treatment such as a cornea transplant.
It’s recommended that immediate family members of the patient undergo an ophthalmological examination, even though they may not show any signs of being affected, as they could be carriers of the condition.
How is keratoconus treated?
Depending on the stage of the condition there are several possible treatments available.
In the mildest forms of keratoconus, glasses to correct astigmatism can improve sharpness of sight. In the majority of cases, rigid contact lenses are required to correct irregular astigmatism. In more serious cases, it may be necessary to resort to surgery such as intrastromal corneal rings to regulate the cornea and correct the astigmatism. At our centre we have the later generation of laser technology to insert the intrastromal corneal rings with the maximum precision and effectiveness.
Recently a special technique called cross-linking has been developed to strengthen the weakened cornea. Cross-linking consists of applying Riboflavin eye drops and then administering UVA radiation. Cross-linking is recommended for those patients whose keratoconus has advanced since the treatment slows down its progress. At Clínica Castilla we are able to offer this innovative treatment which is administered on an outpatient basis.
In the most serious of cases when vision has decreased significantly, the only solution is keroplasty or a cornea transplant. In many cases a transplant can currently be performed by selectively replacing the affected layers of the cornea and preserving the healthy tissue.